/* i915_irq.c -- IRQ support for the I915 -*- linux-c -*-
 */
/*
 * Copyright 2003 Tungsten Graphics, Inc., Cedar Park, Texas.
 * All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sub license, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice (including the
 * next paragraph) shall be included in all copies or substantial portions
 * of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
 * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/sysrq.h>
#include <linux/slab.h>
#include <linux/circ_buf.h>
#include <drm/drmP.h>
#include <drm/i915_drm.h>
#include "i915_drv.h"
#include "i915_trace.h"
#include "intel_drv.h"

/**
 * DOC: interrupt handling
 *
 * These functions provide the basic support for enabling and disabling the
 * interrupt handling support. There's a lot more functionality in i915_irq.c
 * and related files, but that will be described in separate chapters.
 */

static const u32 hpd_ilk[HPD_NUM_PINS] = {
        [HPD_PORT_A] = DE_DP_A_HOTPLUG,
};

static const u32 hpd_ivb[HPD_NUM_PINS] = {
        [HPD_PORT_A] = DE_DP_A_HOTPLUG_IVB,
};

static const u32 hpd_bdw[HPD_NUM_PINS] = {
        [HPD_PORT_A] = GEN8_PORT_DP_A_HOTPLUG,
};

static const u32 hpd_ibx[HPD_NUM_PINS] = {
        [HPD_CRT] = SDE_CRT_HOTPLUG,
        [HPD_SDVO_B] = SDE_SDVOB_HOTPLUG,
        [HPD_PORT_B] = SDE_PORTB_HOTPLUG,
        [HPD_PORT_C] = SDE_PORTC_HOTPLUG,
        [HPD_PORT_D] = SDE_PORTD_HOTPLUG
};

static const u32 hpd_cpt[HPD_NUM_PINS] = {
        [HPD_CRT] = SDE_CRT_HOTPLUG_CPT,
        [HPD_SDVO_B] = SDE_SDVOB_HOTPLUG_CPT,
        [HPD_PORT_B] = SDE_PORTB_HOTPLUG_CPT,
        [HPD_PORT_C] = SDE_PORTC_HOTPLUG_CPT,
        [HPD_PORT_D] = SDE_PORTD_HOTPLUG_CPT
};

static const u32 hpd_spt[HPD_NUM_PINS] = {
        [HPD_PORT_A] = SDE_PORTA_HOTPLUG_SPT,
        [HPD_PORT_B] = SDE_PORTB_HOTPLUG_CPT,
        [HPD_PORT_C] = SDE_PORTC_HOTPLUG_CPT,
        [HPD_PORT_D] = SDE_PORTD_HOTPLUG_CPT,
        [HPD_PORT_E] = SDE_PORTE_HOTPLUG_SPT
};

static const u32 hpd_mask_i915[HPD_NUM_PINS] = {
        [HPD_CRT] = CRT_HOTPLUG_INT_EN,
        [HPD_SDVO_B] = SDVOB_HOTPLUG_INT_EN,
        [HPD_SDVO_C] = SDVOC_HOTPLUG_INT_EN,
        [HPD_PORT_B] = PORTB_HOTPLUG_INT_EN,
        [HPD_PORT_C] = PORTC_HOTPLUG_INT_EN,
        [HPD_PORT_D] = PORTD_HOTPLUG_INT_EN
};

static const u32 hpd_status_g4x[HPD_NUM_PINS] = {
        [HPD_CRT] = CRT_HOTPLUG_INT_STATUS,
        [HPD_SDVO_B] = SDVOB_HOTPLUG_INT_STATUS_G4X,
        [HPD_SDVO_C] = SDVOC_HOTPLUG_INT_STATUS_G4X,
        [HPD_PORT_B] = PORTB_HOTPLUG_INT_STATUS,
        [HPD_PORT_C] = PORTC_HOTPLUG_INT_STATUS,
        [HPD_PORT_D] = PORTD_HOTPLUG_INT_STATUS
};

static const u32 hpd_status_i915[HPD_NUM_PINS] = {
        [HPD_CRT] = CRT_HOTPLUG_INT_STATUS,
        [HPD_SDVO_B] = SDVOB_HOTPLUG_INT_STATUS_I915,
        [HPD_SDVO_C] = SDVOC_HOTPLUG_INT_STATUS_I915,
        [HPD_PORT_B] = PORTB_HOTPLUG_INT_STATUS,
        [HPD_PORT_C] = PORTC_HOTPLUG_INT_STATUS,
        [HPD_PORT_D] = PORTD_HOTPLUG_INT_STATUS
};

/* BXT hpd list */
static const u32 hpd_bxt[HPD_NUM_PINS] = {
        [HPD_PORT_A] = BXT_DE_PORT_HP_DDIA,
        [HPD_PORT_B] = BXT_DE_PORT_HP_DDIB,
        [HPD_PORT_C] = BXT_DE_PORT_HP_DDIC
};

/* IIR can theoretically queue up two events. Be paranoid. */
#define GEN8_IRQ_RESET_NDX(type, which) do { \
        I915_WRITE(GEN8_##type##_IMR(which), 0xffffffff); \
        POSTING_READ(GEN8_##type##_IMR(which)); \
        I915_WRITE(GEN8_##type##_IER(which), 0); \
        I915_WRITE(GEN8_##type##_IIR(which), 0xffffffff); \
        POSTING_READ(GEN8_##type##_IIR(which)); \
        I915_WRITE(GEN8_##type##_IIR(which), 0xffffffff); \
        POSTING_READ(GEN8_##type##_IIR(which)); \
} while (0)

#define GEN5_IRQ_RESET(type) do { \
        I915_WRITE(type##IMR, 0xffffffff); \
        POSTING_READ(type##IMR); \
        I915_WRITE(type##IER, 0); \
        I915_WRITE(type##IIR, 0xffffffff); \
        POSTING_READ(type##IIR); \
        I915_WRITE(type##IIR, 0xffffffff); \
        POSTING_READ(type##IIR); \
} while (0)

/*
 * We should clear IMR at preinstall/uninstall, and just check at postinstall.
 */
static void gen5_assert_iir_is_zero(struct drm_i915_private *dev_priv,
                                    i915_reg_t reg)
{
        u32 val = I915_READ(reg);

        if (val == 0)
                return;

        WARN(1, "Interrupt register 0x%x is not zero: 0x%08x\n",
             i915_mmio_reg_offset(reg), val);
        I915_WRITE(reg, 0xffffffff);
        POSTING_READ(reg);
        I915_WRITE(reg, 0xffffffff);
        POSTING_READ(reg);
}

#define GEN8_IRQ_INIT_NDX(type, which, imr_val, ier_val) do { \
        gen5_assert_iir_is_zero(dev_priv, GEN8_##type##_IIR(which)); \
        I915_WRITE(GEN8_##type##_IER(which), (ier_val)); \
        I915_WRITE(GEN8_##type##_IMR(which), (imr_val)); \
        POSTING_READ(GEN8_##type##_IMR(which)); \
} while (0)

#define GEN5_IRQ_INIT(type, imr_val, ier_val) do { \
        gen5_assert_iir_is_zero(dev_priv, type##IIR); \
        I915_WRITE(type##IER, (ier_val)); \
        I915_WRITE(type##IMR, (imr_val)); \
        POSTING_READ(type##IMR); \
} while (0)

static void gen6_rps_irq_handler(struct drm_i915_private *dev_priv, u32 pm_iir);
static void gen9_guc_irq_handler(struct drm_i915_private *dev_priv, u32 pm_iir);

/* For display hotplug interrupt */
static inline void
i915_hotplug_interrupt_update_locked(struct drm_i915_private *dev_priv,
                                     uint32_t mask,
                                     uint32_t bits)
{
        uint32_t val;

        lockdep_assert_held(&dev_priv->irq_lock);
        WARN_ON(bits & ~mask);

        val = I915_READ(PORT_HOTPLUG_EN);
        val &= ~mask;
        val |= bits;
        I915_WRITE(PORT_HOTPLUG_EN, val);
}

/**
 * i915_hotplug_interrupt_update - update hotplug interrupt enable
 * @dev_priv: driver private
 * @mask: bits to update
 * @bits: bits to enable
 * NOTE: the HPD enable bits are modified both inside and outside
 * of an interrupt context. To avoid that read-modify-write cycles
 * interfer, these bits are protected by a spinlock. Since this
 * function is usually not called from a context where the lock is
 * held already, this function acquires the lock itself. A non-locking
 * version is also available.
 */
void i915_hotplug_interrupt_update(struct drm_i915_private *dev_priv,
                                   uint32_t mask,
                                   uint32_t bits)
{
        spin_lock_irq(&dev_priv->irq_lock);
        i915_hotplug_interrupt_update_locked(dev_priv, mask, bits);
        spin_unlock_irq(&dev_priv->irq_lock);
}

/**
 * ilk_update_display_irq - update DEIMR
 * @dev_priv: driver private
 * @interrupt_mask: mask of interrupt bits to update
 * @enabled_irq_mask: mask of interrupt bits to enable
 */
void ilk_update_display_irq(struct drm_i915_private *dev_priv,
                            uint32_t interrupt_mask,
                            uint32_t enabled_irq_mask)
{
        uint32_t new_val;

        lockdep_assert_held(&dev_priv->irq_lock);

        WARN_ON(enabled_irq_mask & ~interrupt_mask);

        if (WARN_ON(!intel_irqs_enabled(dev_priv)))
                return;

        new_val = dev_priv->irq_mask;
        new_val &= ~interrupt_mask;
        new_val |= (~enabled_irq_mask & interrupt_mask);

        if (new_val != dev_priv->irq_mask) {
                dev_priv->irq_mask = new_val;
                I915_WRITE(DEIMR, dev_priv->irq_mask);
                POSTING_READ(DEIMR);
        }
}

/**
 * ilk_update_gt_irq - update GTIMR
 * @dev_priv: driver private
 * @interrupt_mask: mask of interrupt bits to update
 * @enabled_irq_mask: mask of interrupt bits to enable
 */
static void ilk_update_gt_irq(struct drm_i915_private *dev_priv,
                              uint32_t interrupt_mask,
                              uint32_t enabled_irq_mask)
{
        lockdep_assert_held(&dev_priv->irq_lock);

        WARN_ON(enabled_irq_mask & ~interrupt_mask);

        if (WARN_ON(!intel_irqs_enabled(dev_priv)))
                return;

        dev_priv->gt_irq_mask &= ~interrupt_mask;
        dev_priv->gt_irq_mask |= (~enabled_irq_mask & interrupt_mask);
        I915_WRITE(GTIMR, dev_priv->gt_irq_mask);
}

void gen5_enable_gt_irq(struct drm_i915_private *dev_priv, uint32_t mask)
{
        ilk_update_gt_irq(dev_priv, mask, mask);
        POSTING_READ_FW(GTIMR);
}

void gen5_disable_gt_irq(struct drm_i915_private *dev_priv, uint32_t mask)
{
        ilk_update_gt_irq(dev_priv, mask, 0);
}

static i915_reg_t gen6_pm_iir(struct drm_i915_private *dev_priv)
{
        return INTEL_GEN(dev_priv) >= 8 ? GEN8_GT_IIR(2) : GEN6_PMIIR;
}

static i915_reg_t gen6_pm_imr(struct drm_i915_private *dev_priv)
{
        return INTEL_GEN(dev_priv) >= 8 ? GEN8_GT_IMR(2) : GEN6_PMIMR;
}

static i915_reg_t gen6_pm_ier(struct drm_i915_private *dev_priv)
{
        return INTEL_GEN(dev_priv) >= 8 ? GEN8_GT_IER(2) : GEN6_PMIER;
}

/**
 * snb_update_pm_irq - update GEN6_PMIMR
 * @dev_priv: driver private
 * @interrupt_mask: mask of interrupt bits to update
 * @enabled_irq_mask: mask of interrupt bits to enable
 */
static void snb_update_pm_irq(struct drm_i915_private *dev_priv,
                              uint32_t interrupt_mask,
                              uint32_t enabled_irq_mask)
{
        uint32_t new_val;

        WARN_ON(enabled_irq_mask & ~interrupt_mask);

        lockdep_assert_held(&dev_priv->irq_lock);

        new_val = dev_priv->pm_imr;
        new_val &= ~interrupt_mask;
        new_val |= (~enabled_irq_mask & interrupt_mask);

        if (new_val != dev_priv->pm_imr) {
                dev_priv->pm_imr = new_val;
                I915_WRITE(gen6_pm_imr(dev_priv), dev_priv->pm_imr);
                POSTING_READ(gen6_pm_imr(dev_priv));
        }
}

void gen6_unmask_pm_irq(struct drm_i915_private *dev_priv, u32 mask)
{
        if (WARN_ON(!intel_irqs_enabled(dev_priv)))
                return;

        snb_update_pm_irq(dev_priv, mask, mask);
}

static void __gen6_mask_pm_irq(struct drm_i915_private *dev_priv, u32 mask)
{
        snb_update_pm_irq(dev_priv, mask, 0);
}

void gen6_mask_pm_irq(struct drm_i915_private *dev_priv, u32 mask)
{
        if (WARN_ON(!intel_irqs_enabled(dev_priv)))
                return;

        __gen6_mask_pm_irq(dev_priv, mask);
}

void gen6_reset_pm_iir(struct drm_i915_private *dev_priv, u32 reset_mask)
{
        i915_reg_t reg = gen6_pm_iir(dev_priv);

        lockdep_assert_held(&dev_priv->irq_lock);

        I915_WRITE(reg, reset_mask);
        I915_WRITE(reg, reset_mask);
        POSTING_READ(reg);
}

void gen6_enable_pm_irq(struct drm_i915_private *dev_priv, u32 enable_mask)
{
        lockdep_assert_held(&dev_priv->irq_lock);

        dev_priv->pm_ier |= enable_mask;
        I915_WRITE(gen6_pm_ier(dev_priv), dev_priv->pm_ier);
        gen6_unmask_pm_irq(dev_priv, enable_mask);
        /* unmask_pm_irq provides an implicit barrier (POSTING_READ) */
}

void gen6_disable_pm_irq(struct drm_i915_private *dev_priv, u32 disable_mask)
{
        lockdep_assert_held(&dev_priv->irq_lock);

        dev_priv->pm_ier &= ~disable_mask;
        __gen6_mask_pm_irq(dev_priv, disable_mask);
        I915_WRITE(gen6_pm_ier(dev_priv), dev_priv->pm_ier);
        /* though a barrier is missing here, but don't really need a one */
}

void gen6_reset_rps_interrupts(struct drm_i915_private *dev_priv)
{
        spin_lock_irq(&dev_priv->irq_lock);
        gen6_reset_pm_iir(dev_priv, dev_priv->pm_rps_events);
        dev_priv->rps.pm_iir = 0;
        spin_unlock_irq(&dev_priv->irq_lock);
}

void gen6_enable_rps_interrupts(struct drm_i915_private *dev_priv)
{
        if (READ_ONCE(dev_priv->rps.interrupts_enabled))
                return;

        spin_lock_irq(&dev_priv->irq_lock);
        WARN_ON_ONCE(dev_priv->rps.pm_iir);
        WARN_ON_ONCE(I915_READ(gen6_pm_iir(dev_priv)) & dev_priv->pm_rps_events);
        dev_priv->rps.interrupts_enabled = true;
        gen6_enable_pm_irq(dev_priv, dev_priv->pm_rps_events);

        spin_unlock_irq(&dev_priv->irq_lock);
}

void gen6_disable_rps_interrupts(struct drm_i915_private *dev_priv)
{
        if (!READ_ONCE(dev_priv->rps.interrupts_enabled))
                return;

        spin_lock_irq(&dev_priv->irq_lock);
        dev_priv->rps.interrupts_enabled = false;

        I915_WRITE(GEN6_PMINTRMSK, gen6_sanitize_rps_pm_mask(dev_priv, ~0u));

        gen6_disable_pm_irq(dev_priv, dev_priv->pm_rps_events);

        spin_unlock_irq(&dev_priv->irq_lock);
        synchronize_irq(dev_priv->drm.irq);

        /* Now that we will not be generating any more work, flush any
         * outsanding tasks. As we are called on the RPS idle path,
         * we will reset the GPU to minimum frequencies, so the current
         * state of the worker can be discarded.
         */
        cancel_work_sync(&dev_priv->rps.work);
        gen6_reset_rps_interrupts(dev_priv);
}

void gen9_reset_guc_interrupts(struct drm_i915_private *dev_priv)
{
        spin_lock_irq(&dev_priv->irq_lock);
        gen6_reset_pm_iir(dev_priv, dev_priv->pm_guc_events);
        spin_unlock_irq(&dev_priv->irq_lock);
}

void gen9_enable_guc_interrupts(struct drm_i915_private *dev_priv)
{
        spin_lock_irq(&dev_priv->irq_lock);
        if (!dev_priv->guc.interrupts_enabled) {
                WARN_ON_ONCE(I915_READ(gen6_pm_iir(dev_priv)) &
                                       dev_priv->pm_guc_events);
                dev_priv->guc.interrupts_enabled = true;
                gen6_enable_pm_irq(dev_priv, dev_priv->pm_guc_events);
        }
        spin_unlock_irq(&dev_priv->irq_lock);
}

void gen9_disable_guc_interrupts(struct drm_i915_private *dev_priv)
{
        spin_lock_irq(&dev_priv->irq_lock);
        dev_priv->guc.interrupts_enabled = false;

        gen6_disable_pm_irq(dev_priv, dev_priv->pm_guc_events);

        spin_unlock_irq(&dev_priv->irq_lock);
        synchronize_irq(dev_priv->drm.irq);

        gen9_reset_guc_interrupts(dev_priv);
}

/**
 * bdw_update_port_irq - update DE port interrupt
 * @dev_priv: driver private
 * @interrupt_mask: mask of interrupt bits to update
 * @enabled_irq_mask: mask of interrupt bits to enable
 */
static void bdw_update_port_irq(struct drm_i915_private *dev_priv,
                                uint32_t interrupt_mask,
                                uint32_t enabled_irq_mask)
{
        uint32_t new_val;
        uint32_t old_val;

        lockdep_assert_held(&dev_priv->irq_lock);

        WARN_ON(enabled_irq_mask & ~interrupt_mask);

        if (WARN_ON(!intel_irqs_enabled(dev_priv)))
                return;

        old_val = I915_READ(GEN8_DE_PORT_IMR);

        new_val = old_val;
        new_val &= ~interrupt_mask;
        new_val |= (~enabled_irq_mask & interrupt_mask);

        if (new_val != old_val) {
                I915_WRITE(GEN8_DE_PORT_IMR, new_val);
                POSTING_READ(GEN8_DE_PORT_IMR);
        }
}

/**
 * bdw_update_pipe_irq - update DE pipe interrupt
 * @dev_priv: driver private
 * @pipe: pipe whose interrupt to update
 * @interrupt_mask: mask of interrupt bits to update
 * @enabled_irq_mask: mask of interrupt bits to enable
 */
void bdw_update_pipe_irq(struct drm_i915_private *dev_priv,
                         enum pipe pipe,
                         uint32_t interrupt_mask,
                         uint32_t enabled_irq_mask)
{
        uint32_t new_val;

        lockdep_assert_held(&dev_priv->irq_lock);

        WARN_ON(enabled_irq_mask & ~interrupt_mask);

        if (WARN_ON(!intel_irqs_enabled(dev_priv)))
                return;

        new_val = dev_priv->de_irq_mask[pipe];
        new_val &= ~interrupt_mask;
        new_val |= (~enabled_irq_mask & interrupt_mask);

        if (new_val != dev_priv->de_irq_mask[pipe]) {
                dev_priv->de_irq_mask[pipe] = new_val;
                I915_WRITE(GEN8_DE_PIPE_IMR(pipe), dev_priv->de_irq_mask[pipe]);
                POSTING_READ(GEN8_DE_PIPE_IMR(pipe));
        }
}

/**
 * ibx_display_interrupt_update - update SDEIMR
 * @dev_priv: driver private
 * @interrupt_mask: mask of interrupt bits to update
 * @enabled_irq_mask: mask of interrupt bits to enable
 */
void ibx_display_interrupt_update(struct drm_i915_private *dev_priv,
                                  uint32_t interrupt_mask,
                                  uint32_t enabled_irq_mask)
{
        uint32_t sdeimr = I915_READ(SDEIMR);
        sdeimr &= ~interrupt_mask;
        sdeimr |= (~enabled_irq_mask & interrupt_mask);

        WARN_ON(enabled_irq_mask & ~interrupt_mask);

        lockdep_assert_held(&dev_priv->irq_lock);

        if (WARN_ON(!intel_irqs_enabled(dev_priv)))
                return;

        I915_WRITE(SDEIMR, sdeimr);
        POSTING_READ(SDEIMR);
}

static void
__i915_enable_pipestat(struct drm_i915_private *dev_priv, enum pipe pipe,
                       u32 enable_mask, u32 status_mask)
{
        i915_reg_t reg = PIPESTAT(pipe);
        u32 pipestat = I915_READ(reg) & PIPESTAT_INT_ENABLE_MASK;

        lockdep_assert_held(&dev_priv->irq_lock);
        WARN_ON(!intel_irqs_enabled(dev_priv));

        if (WARN_ONCE(enable_mask & ~PIPESTAT_INT_ENABLE_MASK ||
                      status_mask & ~PIPESTAT_INT_STATUS_MASK,
                      "pipe %c: enable_mask=0x%x, status_mask=0x%x\n",
                      pipe_name(pipe), enable_mask, status_mask))
                return;

        if ((pipestat & enable_mask) == enable_mask)
                return;

        dev_priv->pipestat_irq_mask[pipe] |= status_mask;

        /* Enable the interrupt, clear any pending status */
        pipestat |= enable_mask | status_mask;
        I915_WRITE(reg, pipestat);
        POSTING_READ(reg);
}

static void
__i915_disable_pipestat(struct drm_i915_private *dev_priv, enum pipe pipe,
                        u32 enable_mask, u32 status_mask)
{
        i915_reg_t reg = PIPESTAT(pipe);
        u32 pipestat = I915_READ(reg) & PIPESTAT_INT_ENABLE_MASK;

        lockdep_assert_held(&dev_priv->irq_lock);
        WARN_ON(!intel_irqs_enabled(dev_priv));

        if (WARN_ONCE(enable_mask & ~PIPESTAT_INT_ENABLE_MASK ||
                      status_mask & ~PIPESTAT_INT_STATUS_MASK,
                      "pipe %c: enable_mask=0x%x, status_mask=0x%x\n",
                      pipe_name(pipe), enable_mask, status_mask))
                return;

        if ((pipestat & enable_mask) == 0)
                return;

        dev_priv->pipestat_irq_mask[pipe] &= ~status_mask;

        pipestat &= ~enable_mask;
        I915_WRITE(reg, pipestat);
        POSTING_READ(reg);
}

static u32 vlv_get_pipestat_enable_mask(struct drm_device *dev, u32 status_mask)
{
        u32 enable_mask = status_mask << 16;

        /*
         * On pipe A we don't support the PSR interrupt yet,
         * on pipe B and C the same bit MBZ.
         */
        if (WARN_ON_ONCE(status_mask & PIPE_A_PSR_STATUS_VLV))
                return 0;
        /*
         * On pipe B and C we don't support the PSR interrupt yet, on pipe
         * A the same bit is for perf counters which we don't use either.
         */
        if (WARN_ON_ONCE(status_mask & PIPE_B_PSR_STATUS_VLV))
                return 0;

        enable_mask &= ~(PIPE_FIFO_UNDERRUN_STATUS |
                         SPRITE0_FLIP_DONE_INT_EN_VLV |
                         SPRITE1_FLIP_DONE_INT_EN_VLV);
        if (status_mask & SPRITE0_FLIP_DONE_INT_STATUS_VLV)
                enable_mask |= SPRITE0_FLIP_DONE_INT_EN_VLV;
        if (status_mask & SPRITE1_FLIP_DONE_INT_STATUS_VLV)
                enable_mask |= SPRITE1_FLIP_DONE_INT_EN_VLV;

        return enable_mask;
}

void
i915_enable_pipestat(struct drm_i915_private *dev_priv, enum pipe pipe,
                     u32 status_mask)
{
        u32 enable_mask;

        if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv))
                enable_mask = vlv_get_pipestat_enable_mask(&dev_priv->drm,
                                                           status_mask);
        else
                enable_mask = status_mask << 16;
        __i915_enable_pipestat(dev_priv, pipe, enable_mask, status_mask);
}

void
i915_disable_pipestat(struct drm_i915_private *dev_priv, enum pipe pipe,
                      u32 status_mask)
{
        u32 enable_mask;

        if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv))
                enable_mask = vlv_get_pipestat_enable_mask(&dev_priv->drm,
                                                           status_mask);
        else
                enable_mask = status_mask << 16;
        __i915_disable_pipestat(dev_priv, pipe, enable_mask, status_mask);
}

/**
 * i915_enable_asle_pipestat - enable ASLE pipestat for OpRegion
 * @dev_priv: i915 device private
 */
static void i915_enable_asle_pipestat(struct drm_i915_private *dev_priv)
{
        if (!dev_priv->opregion.asle || !IS_MOBILE(dev_priv))
                return;

        spin_lock_irq(&dev_priv->irq_lock);

        i915_enable_pipestat(dev_priv, PIPE_B, PIPE_LEGACY_BLC_EVENT_STATUS);
        if (INTEL_GEN(dev_priv) >= 4)
                i915_enable_pipestat(dev_priv, PIPE_A,
                                     PIPE_LEGACY_BLC_EVENT_STATUS);

        spin_unlock_irq(&dev_priv->irq_lock);
}

/*
 * This timing diagram depicts the video signal in and
 * around the vertical blanking period.
 *
 * Assumptions about the fictitious mode used in this example:
 *  vblank_start >= 3
 *  vsync_start = vblank_start + 1
 *  vsync_end = vblank_start + 2
 *  vtotal = vblank_start + 3
 *
 *           start of vblank:
 *           latch double buffered registers
 *           increment frame counter (ctg+)
 *           generate start of vblank interrupt (gen4+)
 *           |
 *           |          frame start:
 *           |          generate frame start interrupt (aka. vblank interrupt) (gmch)
 *           |          may be shifted forward 1-3 extra lines via PIPECONF
 *           |          |
 *           |          |  start of vsync:
 *           |          |  generate vsync interrupt
 *           |          |  |
 * ___xxxx___    ___xxxx___    ___xxxx___    ___xxxx___    ___xxxx___    ___xxxx
 *       .   \hs/   .      \hs/          \hs/          \hs/   .      \hs/
 * ----va---> <-----------------vb--------------------> <--------va-------------
 *       |          |       <----vs----->                     |
 * -vbs-----> <---vbs+1---> <---vbs+2---> <-----0-----> <-----1-----> <-----2--- (scanline counter gen2)
 * -vbs-2---> <---vbs-1---> <---vbs-----> <---vbs+1---> <---vbs+2---> <-----0--- (scanline counter gen3+)
 * -vbs-2---> <---vbs-2---> <---vbs-1---> <---vbs-----> <---vbs+1---> <---vbs+2- (scanline counter hsw+ hdmi)
 *       |          |                                         |
 *       last visible pixel                                   first visible pixel
 *                  |                                         increment frame counter (gen3/4)
 *                  pixel counter = vblank_start * htotal     pixel counter = 0 (gen3/4)
 *
 * x  = horizontal active
 * _  = horizontal blanking
 * hs = horizontal sync
 * va = vertical active
 * vb = vertical blanking
 * vs = vertical sync
 * vbs = vblank_start (number)
 *
 * Summary:
 * - most events happen at the start of horizontal sync
 * - frame start happens at the start of horizontal blank, 1-4 lines
 *   (depending on PIPECONF settings) after the start of vblank
 * - gen3/4 pixel and frame counter are synchronized with the start
 *   of horizontal active on the first line of vertical active
 */

/* Called from drm generic code, passed a 'crtc', which
 * we use as a pipe index
 */
static u32 i915_get_vblank_counter(struct drm_device *dev, unsigned int pipe)
{
        struct drm_i915_private *dev_priv = to_i915(dev);
        i915_reg_t high_frame, low_frame;
        u32 high1, high2, low, pixel, vbl_start, hsync_start, htotal;
        const struct drm_display_mode *mode = &dev->vblank[pipe].hwmode;
        unsigned long irqflags;

        htotal = mode->crtc_htotal;
        hsync_start = mode->crtc_hsync_start;
        vbl_start = mode->crtc_vblank_start;
        if (mode->flags & DRM_MODE_FLAG_INTERLACE)
                vbl_start = DIV_ROUND_UP(vbl_start, 2);

        /* Convert to pixel count */
        vbl_start *= htotal;

        /* Start of vblank event occurs at start of hsync */
        vbl_start -= htotal - hsync_start;

        high_frame = PIPEFRAME(pipe);
        low_frame = PIPEFRAMEPIXEL(pipe);

        spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);

        /*
         * High & low register fields aren't synchronized, so make sure
         * we get a low value that's stable across two reads of the high
         * register.
         */
        do {
                high1 = I915_READ_FW(high_frame) & PIPE_FRAME_HIGH_MASK;
                low   = I915_READ_FW(low_frame);
                high2 = I915_READ_FW(high_frame) & PIPE_FRAME_HIGH_MASK;
        } while (high1 != high2);

        spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);

        high1 >>= PIPE_FRAME_HIGH_SHIFT;
        pixel = low & PIPE_PIXEL_MASK;
        low >>= PIPE_FRAME_LOW_SHIFT;

        /*
         * The frame counter increments at beginning of active.
         * Cook up a vblank counter by also checking the pixel
         * counter against vblank start.
         */
        return (((high1 << 8) | low) + (pixel >= vbl_start)) & 0xffffff;
}

static u32 g4x_get_vblank_counter(struct drm_device *dev, unsigned int pipe)
{
        struct drm_i915_private *dev_priv = to_i915(dev);

        return I915_READ(PIPE_FRMCOUNT_G4X(pipe));
}

/* I915_READ_FW, only for fast reads of display block, no need for forcewake etc. */
static int __intel_get_crtc_scanline(struct intel_crtc *crtc)
{
        struct drm_device *dev = crtc->base.dev;
        struct drm_i915_private *dev_priv = to_i915(dev);
        const struct drm_display_mode *mode;
        struct drm_vblank_crtc *vblank;
        enum pipe pipe = crtc->pipe;
        int position, vtotal;

        if (!crtc->active)
                return -1;

        vblank = &crtc->base.dev->vblank[drm_crtc_index(&crtc->base)];
        mode = &vblank->hwmode;

        vtotal = mode->crtc_vtotal;
        if (mode->flags & DRM_MODE_FLAG_INTERLACE)
                vtotal /= 2;

        if (IS_GEN2(dev_priv))
                position = I915_READ_FW(PIPEDSL(pipe)) & DSL_LINEMASK_GEN2;
        else
                position = I915_READ_FW(PIPEDSL(pipe)) & DSL_LINEMASK_GEN3;

        /*
         * On HSW, the DSL reg (0x70000) appears to return 0 if we
         * read it just before the start of vblank.  So try it again
         * so we don't accidentally end up spanning a vblank frame
         * increment, causing the pipe_update_end() code to squak at us.
         *
         * The nature of this problem means we can't simply check the ISR
         * bit and return the vblank start value; nor can we use the scanline
         * debug register in the transcoder as it appears to have the same
         * problem.  We may need to extend this to include other platforms,
         * but so far testing only shows the problem on HSW.
         */
        if (HAS_DDI(dev_priv) && !position) {
                int i, temp;

                for (i = 0; i < 100; i++) {
                        udelay(1);
                        temp = I915_READ_FW(PIPEDSL(pipe)) & DSL_LINEMASK_GEN3;
                        if (temp != position) {
                                position = temp;
                                break;
                        }
                }
        }

        /*
         * See update_scanline_offset() for the details on the
         * scanline_offset adjustment.
         */
        return (position + crtc->scanline_offset) % vtotal;
}

static bool i915_get_crtc_scanoutpos(struct drm_device *dev, unsigned int pipe,
                                     bool in_vblank_irq, int *vpos, int *hpos,
                                     ktime_t *stime, ktime_t *etime,
                                     const struct drm_display_mode *mode)
{
        struct drm_i915_private *dev_priv = to_i915(dev);
        struct intel_crtc *intel_crtc = intel_get_crtc_for_pipe(dev_priv,
                                                                pipe);
        int position;
        int vbl_start, vbl_end, hsync_start, htotal, vtotal;
        unsigned long irqflags;

        if (WARN_ON(!mode->crtc_clock)) {
                DRM_DEBUG_DRIVER("trying to get scanoutpos for disabled "
                                 "pipe %c\n", pipe_name(pipe));
                return false;
        }

        htotal = mode->crtc_htotal;
        hsync_start = mode->crtc_hsync_start;
        vtotal = mode->crtc_vtotal;
        vbl_start = mode->crtc_vblank_start;
        vbl_end = mode->crtc_vblank_end;

        if (mode->flags & DRM_MODE_FLAG_INTERLACE) {
                vbl_start = DIV_ROUND_UP(vbl_start, 2);
                vbl_end /= 2;
                vtotal /= 2;
        }

        /*
         * Lock uncore.lock, as we will do multiple timing critical raw
         * register reads, potentially with preemption disabled, so the
         * following code must not block on uncore.lock.
         */
        spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);

        /* preempt_disable_rt() should go right here in PREEMPT_RT patchset. */

        /* Get optional system timestamp before query. */
        if (stime)
                *stime = ktime_get();

        if (IS_GEN2(dev_priv) || IS_G4X(dev_priv) || INTEL_GEN(dev_priv) >= 5) {
                /* No obvious pixelcount register. Only query vertical
                 * scanout position from Display scan line register.
                 */
                position = __intel_get_crtc_scanline(intel_crtc);
        } else {
                /* Have access to pixelcount since start of frame.
                 * We can split this into vertical and horizontal
                 * scanout position.
                 */
                position = (I915_READ_FW(PIPEFRAMEPIXEL(pipe)) & PIPE_PIXEL_MASK) >> PIPE_PIXEL_SHIFT;

                /* convert to pixel counts */
                vbl_start *= htotal;
                vbl_end *= htotal;
                vtotal *= htotal;

                /*
                 * In interlaced modes, the pixel counter counts all pixels,
                 * so one field will have htotal more pixels. In order to avoid
                 * the reported position from jumping backwards when the pixel
                 * counter is beyond the length of the shorter field, just
                 * clamp the position the length of the shorter field. This
                 * matches how the scanline counter based position works since
                 * the scanline counter doesn't count the two half lines.
                 */
                if (position >= vtotal)
                        position = vtotal - 1;

                /*
                 * Start of vblank interrupt is triggered at start of hsync,
                 * just prior to the first active line of vblank. However we
                 * consider lines to start at the leading edge of horizontal
                 * active. So, should we get here before we've crossed into
                 * the horizontal active of the first line in vblank, we would
                 * not set the DRM_SCANOUTPOS_INVBL flag. In order to fix that,
                 * always add htotal-hsync_start to the current pixel position.
                 */
                position = (position + htotal - hsync_start) % vtotal;
        }

        /* Get optional system timestamp after query. */
        if (etime)
                *etime = ktime_get();

        /* preempt_enable_rt() should go right here in PREEMPT_RT patchset. */

        spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);

        /*
         * While in vblank, position will be negative
         * counting up towards 0 at vbl_end. And outside
         * vblank, position will be positive counting
         * up since vbl_end.
         */
        if (position >= vbl_start)
                position -= vbl_end;
        else
                position += vtotal - vbl_end;

        if (IS_GEN2(dev_priv) || IS_G4X(dev_priv) || INTEL_GEN(dev_priv) >= 5) {
                *vpos = position;
                *hpos = 0;
        } else {
                *vpos = position / htotal;
                *hpos = position - (*vpos * htotal);
        }

        return true;
}

int intel_get_crtc_scanline(struct intel_crtc *crtc)
{
        struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
        unsigned long irqflags;
        int position;

        spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);
        position = __intel_get_crtc_scanline(crtc);
        spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);

        return position;
}

static void ironlake_rps_change_irq_handler(struct drm_i915_private *dev_priv)
{
        u32 busy_up, busy_down, max_avg, min_avg;
        u8 new_delay;

        spin_lock(&mchdev_lock);

        I915_WRITE16(MEMINTRSTS, I915_READ(MEMINTRSTS));

        new_delay = dev_priv->ips.cur_delay;

        I915_WRITE16(MEMINTRSTS, MEMINT_EVAL_CHG);
        busy_up = I915_READ(RCPREVBSYTUPAVG);
        busy_down = I915_READ(RCPREVBSYTDNAVG);
        max_avg = I915_READ(RCBMAXAVG);
        min_avg = I915_READ(RCBMINAVG);

        /* Handle RCS change request from hw */
        if (busy_up > max_avg) {
                if (dev_priv->ips.cur_delay != dev_priv->ips.max_delay)
                        new_delay = dev_priv->ips.cur_delay - 1;
                if (new_delay < dev_priv->ips.max_delay)
                        new_delay = dev_priv->ips.max_delay;
        } else if (busy_down < min_avg) {
                if (dev_priv->ips.cur_delay != dev_priv->ips.min_delay)
                        new_delay = dev_priv->ips.cur_delay + 1;
                if (new_delay > dev_priv->ips.min_delay)
                        new_delay = dev_priv->ips.min_delay;
        }

        if (ironlake_set_drps(dev_priv, new_delay))
                dev_priv->ips.cur_delay = new_delay;

        spin_unlock(&mchdev_lock);

        return;
}

static void notify_ring(struct intel_engine_cs *engine)
{
        struct drm_i915_gem_request *rq = NULL;
        struct intel_wait *wait;

        atomic_inc(&engine->irq_count);
        set_bit(ENGINE_IRQ_BREADCRUMB, &engine->irq_posted);

        spin_lock(&engine->breadcrumbs.irq_lock);
        wait = engine->breadcrumbs.irq_wait;
        if (wait) {
                /* We use a callback from the dma-fence to submit
                 * requests after waiting on our own requests. To
                 * ensure minimum delay in queuing the next request to
                 * hardware, signal the fence now rather than wait for
                 * the signaler to be woken up. We still wake up the
                 * waiter in order to handle the irq-seqno coherency
                 * issues (we may receive the interrupt before the
                 * seqno is written, see __i915_request_irq_complete())
                 * and to handle coalescing of multiple seqno updates
                 * and many waiters.
                 */
                if (i915_seqno_passed(intel_engine_get_seqno(engine),
                                      wait->seqno) &&
                    !test_bit(DMA_FENCE_FLAG_SIGNALED_BIT,
                              &wait->request->fence.flags))
                        rq = i915_gem_request_get(wait->request);

                wake_up_process(wait->tsk);
        } else {
                __intel_engine_disarm_breadcrumbs(engine);
        }
        spin_unlock(&engine->breadcrumbs.irq_lock);

        if (rq) {
                dma_fence_signal(&rq->fence);
                i915_gem_request_put(rq);
        }

        trace_intel_engine_notify(engine, wait);
}

static void vlv_c0_read(struct drm_i915_private *dev_priv,
                        struct intel_rps_ei *ei)
{
        ei->ktime = ktime_get_raw();
        ei->render_c0 = I915_READ(VLV_RENDER_C0_COUNT);
        ei->media_c0 = I915_READ(VLV_MEDIA_C0_COUNT);
}

void gen6_rps_reset_ei(struct drm_i915_private *dev_priv)
{
        memset(&dev_priv->rps.ei, 0, sizeof(dev_priv->rps.ei));
}

static u32 vlv_wa_c0_ei(struct drm_i915_private *dev_priv, u32 pm_iir)
{
        const struct intel_rps_ei *prev = &dev_priv->rps.ei;
        struct intel_rps_ei now;
        u32 events = 0;

        if ((pm_iir & GEN6_PM_RP_UP_EI_EXPIRED) == 0)
                return 0;

        vlv_c0_read(dev_priv, &now);

        if (prev->ktime) {
                u64 time, c0;
                u32 render, media;

                time = ktime_us_delta(now.ktime, prev->ktime);

                time *= dev_priv->czclk_freq;

                /* Workload can be split between render + media,
                 * e.g. SwapBuffers being blitted in X after being rendered in
                 * mesa. To account for this we need to combine both engines
                 * into our activity counter.
                 */
                render = now.render_c0 - prev->render_c0;
                media = now.media_c0 - prev->media_c0;
                c0 = max(render, media);
                c0 *= 1000 * 100 << 8; /* to usecs and scale to threshold% */

                if (c0 > time * dev_priv->rps.up_threshold)
                        events = GEN6_PM_RP_UP_THRESHOLD;
                else if (c0 < time * dev_priv->rps.down_threshold)
                        events = GEN6_PM_RP_DOWN_THRESHOLD;
        }

        dev_priv->rps.ei = now;
        return events;
}

static void gen6_pm_rps_work(struct work_struct *work)
{
        struct drm_i915_private *dev_priv =
                container_of(work, struct drm_i915_private, rps.work);
        bool client_boost = false;
        int new_delay, adj, min, max;
        u32 pm_iir = 0;

        spin_lock_irq(&dev_priv->irq_lock);
        if (dev_priv->rps.interrupts_enabled) {
                pm_iir = fetch_and_zero(&dev_priv->rps.pm_iir);
                client_boost = atomic_read(&dev_priv->rps.num_waiters);
        }
        spin_unlock_irq(&dev_priv->irq_lock);

        /* Make sure we didn't queue anything we're not going to process. */
        WARN_ON(pm_iir & ~dev_priv->pm_rps_events);
        if ((pm_iir & dev_priv->pm_rps_events) == 0 && !client_boost)
                goto out;

        mutex_lock(&dev_priv->rps.hw_lock);

        pm_iir |= vlv_wa_c0_ei(dev_priv, pm_iir);

        adj = dev_priv->rps.last_adj;
        new_delay = dev_priv->rps.cur_freq;
        min = dev_priv->rps.min_freq_softlimit;
        max = dev_priv->rps.max_freq_softlimit;
        if (client_boost)
                max = dev_priv->rps.max_freq;
        if (client_boost && new_delay < dev_priv->rps.boost_freq) {
                new_delay = dev_priv->rps.boost_freq;
                adj = 0;
        } else if (pm_iir & GEN6_PM_RP_UP_THRESHOLD) {
                if (adj > 0)
                        adj *= 2;
                else /* CHV needs even encode values */
                        adj = IS_CHERRYVIEW(dev_priv) ? 2 : 1;

                if (new_delay >= dev_priv->rps.max_freq_softlimit)
                        adj = 0;
        } else if (client_boost) {
                adj = 0;
        } else if (pm_iir & GEN6_PM_RP_DOWN_TIMEOUT) {
                if (dev_priv->rps.cur_freq > dev_priv->rps.efficient_freq)
                        new_delay = dev_priv->rps.efficient_freq;
                else if (dev_priv->rps.cur_freq > dev_priv->rps.min_freq_softlimit)
                        new_delay = dev_priv->rps.min_freq_softlimit;
                adj = 0;
        } else if (pm_iir & GEN6_PM_RP_DOWN_THRESHOLD) {
                if (adj < 0)
                        adj *= 2;
                else /* CHV needs even encode values */
                        adj = IS_CHERRYVIEW(dev_priv) ? -2 : -1;

                if (new_delay <= dev_priv->rps.min_freq_softlimit)
                        adj = 0;
        } else { /* unknown event */
                adj = 0;
        }

        dev_priv->rps.last_adj = adj;

        /* sysfs frequency interfaces may have snuck in while servicing the
         * interrupt
         */
        new_delay += adj;
        new_delay = clamp_t(int, new_delay, min, max);

        if (intel_set_rps(dev_priv, new_delay)) {
                DRM_DEBUG_DRIVER("Failed to set new GPU frequency\n");
                dev_priv->rps.last_adj = 0;
        }

        mutex_unlock(&dev_priv->rps.hw_lock);

out:
        /* Make sure not to corrupt PMIMR state used by ringbuffer on GEN6 */
        spin_lock_irq(&dev_priv->irq_lock);
        if (dev_priv->rps.interrupts_enabled)
                gen6_unmask_pm_irq(dev_priv, dev_priv->pm_rps_events);
        spin_unlock_irq(&dev_priv->irq_lock);
}


/**
 * ivybridge_parity_work - Workqueue called when a parity error interrupt
 * occurred.
 * @work: workqueue struct
 *
 * Doesn't actually do anything except notify userspace. As a consequence of
 * this event, userspace should try to remap the bad rows since statistically
 * it is likely the same row is more likely to go bad again.
 */
static void ivybridge_parity_work(struct work_struct *work)
{
        struct drm_i915_private *dev_priv =
                container_of(work, typeof(*dev_priv), l3_parity.error_work);
        u32 error_status, row, bank, subbank;
        char *parity_event[6];
        uint32_t misccpctl;
        uint8_t slice = 0;

        /* We must turn off DOP level clock gating to access the L3 registers.
         * In order to prevent a get/put style interface, acquire struct mutex
         * any time we access those registers.
         */
        mutex_lock(&dev_priv->drm.struct_mutex);

        /* If we've screwed up tracking, just let the interrupt fire again */
        if (WARN_ON(!dev_priv->l3_parity.which_slice))
                goto out;

        misccpctl = I915_READ(GEN7_MISCCPCTL);
        I915_WRITE(GEN7_MISCCPCTL, misccpctl & ~GEN7_DOP_CLOCK_GATE_ENABLE);
        POSTING_READ(GEN7_MISCCPCTL);

        while ((slice = ffs(dev_priv->l3_parity.which_slice)) != 0) {
                i915_reg_t reg;

                slice--;
                if (WARN_ON_ONCE(slice >= NUM_L3_SLICES(dev_priv)))
                        break;

                dev_priv->l3_parity.which_slice &= ~(1<<slice);

                reg = GEN7_L3CDERRST1(slice);

                error_status = I915_READ(reg);
                row = GEN7_PARITY_ERROR_ROW(error_status);
                bank = GEN7_PARITY_ERROR_BANK(error_status);
                subbank = GEN7_PARITY_ERROR_SUBBANK(error_status);

                I915_WRITE(reg, GEN7_PARITY_ERROR_VALID | GEN7_L3CDERRST1_ENABLE);
                POSTING_READ(reg);

                parity_event[0] = I915_L3_PARITY_UEVENT "=1";
                parity_event[1] = kasprintf(GFP_KERNEL, "ROW=%d", row);
                parity_event[2] = kasprintf(GFP_KERNEL, "BANK=%d", bank);
                parity_event[3] = kasprintf(GFP_KERNEL, "SUBBANK=%d", subbank);
                parity_event[4] = kasprintf(GFP_KERNEL, "SLICE=%d", slice);
                parity_event[5] = NULL;

                kobject_uevent_env(&dev_priv->drm.primary->kdev->kobj,
                                   KOBJ_CHANGE, parity_event);

                DRM_DEBUG("Parity error: Slice = %d, Row = %d, Bank = %d, Sub bank = %d.\n",
                          slice, row, bank, subbank);

                kfree(parity_event[4]);
                kfree(parity_event[3]);
                kfree(parity_event[2]);
                kfree(parity_event[1]);
        }

        I915_WRITE(GEN7_MISCCPCTL, misccpctl);

out:
        WARN_ON(dev_priv->l3_parity.which_slice);
        spin_lock_irq(&dev_priv->irq_lock);
        gen5_enable_gt_irq(dev_priv, GT_PARITY_ERROR(dev_priv));
        spin_unlock_irq(&dev_priv->irq_lock);

        mutex_unlock(&dev_priv->drm.struct_mutex);
}

static void ivybridge_parity_error_irq_handler(struct drm_i915_private *dev_priv,
                                               u32 iir)
{
        if (!HAS_L3_DPF(dev_priv))
                return;

        spin_lock(&dev_priv->irq_lock);
        gen5_disable_gt_irq(dev_priv, GT_PARITY_ERROR(dev_priv));
        spin_unlock(&dev_priv->irq_lock);

        iir &= GT_PARITY_ERROR(dev_priv);
        if (iir & GT_RENDER_L3_PARITY_ERROR_INTERRUPT_S1)
                dev_priv->l3_parity.which_slice |= 1 << 1;

        if (iir & GT_RENDER_L3_PARITY_ERROR_INTERRUPT)
                dev_priv->l3_parity.which_slice |= 1 << 0;

        queue_work(dev_priv->wq, &dev_priv->l3_parity.error_work);
}

static void ilk_gt_irq_handler(struct drm_i915_private *dev_priv,
                               u32 gt_iir)
{
        if (gt_iir & GT_RENDER_USER_INTERRUPT)
                notify_ring(dev_priv->engine[RCS]);
        if (gt_iir & ILK_BSD_USER_INTERRUPT)
                notify_ring(dev_priv->engine[VCS]);
}

static void snb_gt_irq_handler(struct drm_i915_private *dev_priv,
                               u32 gt_iir)
{
        if (gt_iir & GT_RENDER_USER_INTERRUPT)
                notify_ring(dev_priv->engine[RCS]);
        if (gt_iir & GT_BSD_USER_INTERRUPT)
                notify_ring(dev_priv->engine[VCS]);
        if (gt_iir & GT_BLT_USER_INTERRUPT)
                notify_ring(dev_priv->engine[BCS]);

        if (gt_iir & (GT_BLT_CS_ERROR_INTERRUPT |
                      GT_BSD_CS_ERROR_INTERRUPT |
                      GT_RENDER_CS_MASTER_ERROR_INTERRUPT))
                DRM_DEBUG("Command parser error, gt_iir 0x%08x\n", gt_iir);

        if (gt_iir & GT_PARITY_ERROR(dev_priv))
                ivybridge_parity_error_irq_handler(dev_priv, gt_iir);
}

static void
gen8_cs_irq_handler(struct intel_engine_cs *engine, u32 iir, int test_shift)
{
        bool tasklet = false;

        if (iir & (GT_CONTEXT_SWITCH_INTERRUPT << test_shift)) {
                if (port_count(&engine->execlist_port[0])) {
                        __set_bit(ENGINE_IRQ_EXECLIST, &engine->irq_posted);
                        tasklet = true;
                }
        }

        if (iir & (GT_RENDER_USER_INTERRUPT << test_shift)) {
                notify_ring(engine);
                tasklet |= i915.enable_guc_submission;
        }

        if (tasklet)
                tasklet_hi_schedule(&engine->irq_tasklet);
}

static irqreturn_t gen8_gt_irq_ack(struct drm_i915_private *dev_priv,
                                   u32 master_ctl,
                                   u32 gt_iir[4])
{
        irqreturn_t ret = IRQ_NONE;

        if (master_ctl & (GEN8_GT_RCS_IRQ | GEN8_GT_BCS_IRQ)) {
                gt_iir[0] = I915_READ_FW(GEN8_GT_IIR(0));
                if (gt_iir[0]) {
                        I915_WRITE_FW(GEN8_GT_IIR(0), gt_iir[0]);
                        ret = IRQ_HANDLED;
                } else
                        DRM_ERROR("The master control interrupt lied (GT0)!\n");
        }

        if (master_ctl & (GEN8_GT_VCS1_IRQ | GEN8_GT_VCS2_IRQ)) {
                gt_iir[1] = I915_READ_FW(GEN8_GT_IIR(1));
                if (gt_iir[1]) {
                        I915_WRITE_FW(GEN8_GT_IIR(1), gt_iir[1]);
                        ret = IRQ_HANDLED;
                } else
                        DRM_ERROR("The master control interrupt lied (GT1)!\n");
        }

        if (master_ctl & GEN8_GT_VECS_IRQ) {
                gt_iir[3] = I915_READ_FW(GEN8_GT_IIR(3));
                if (gt_iir[3]) {
                        I915_WRITE_FW(GEN8_GT_IIR(3), gt_iir[3]);
                        ret = IRQ_HANDLED;
                } else
                        DRM_ERROR("The master control interrupt lied (GT3)!\n");
        }

        if (master_ctl & (GEN8_GT_PM_IRQ | GEN8_GT_GUC_IRQ)) {
                gt_iir[2] = I915_READ_FW(GEN8_GT_IIR(2));
                if (gt_iir[2] & (dev_priv->pm_rps_events |
                                 dev_priv->pm_guc_events)) {
                        I915_WRITE_FW(GEN8_GT_IIR(2),
                                      gt_iir[2] & (dev_priv->pm_rps_events |
                                                   dev_priv->pm_guc_events));
                        ret = IRQ_HANDLED;
                } else
                        DRM_ERROR("The master control interrupt lied (PM)!\n");
        }

        return ret;
}

static void gen8_gt_irq_handler(struct drm_i915_private *dev_priv,
                                u32 gt_iir[4])
{
        if (gt_iir[0]) {
                gen8_cs_irq_handler(dev_priv->engine[RCS],
                                    gt_iir[0], GEN8_RCS_IRQ_SHIFT);
                gen8_cs_irq_handler(dev_priv->engine[BCS],
                                    gt_iir[0], GEN8_BCS_IRQ_SHIFT);
        }

        if (gt_iir[1]) {
                gen8_cs_irq_handler(dev_priv->engine[VCS],
                                    gt_iir[1], GEN8_VCS1_IRQ_SHIFT);
                gen8_cs_irq_handler(dev_priv->engine[VCS2],
                                    gt_iir[1], GEN8_VCS2_IRQ_SHIFT);
        }

        if (gt_iir[3])
                gen8_cs_irq_handler(dev_priv->engine[VECS],
                                    gt_iir[3], GEN8_VECS_IRQ_SHIFT);

        if (gt_iir[2] & dev_priv->pm_rps_events)
                gen6_rps_irq_handler(dev_priv, gt_iir[2]);

        if (gt_iir[2] & dev_priv->pm_guc_events)
                gen9_guc_irq_handler(dev_priv, gt_iir[2]);
}

static bool bxt_port_hotplug_long_detect(enum port port, u32 val)
{
        switch (port) {
        case PORT_A:
                return val & PORTA_HOTPLUG_LONG_DETECT;
        case PORT_B:
                return val & PORTB_HOTPLUG_LONG_DETECT;
        case PORT_C:
                return val & PORTC_HOTPLUG_LONG_DETECT;
        default:
                return false;
        }
}

static bool spt_port_hotplug2_long_detect(enum port port, u32 val)
{
        switch (port) {
        case PORT_E:
                return val & PORTE_HOTPLUG_LONG_DETECT;
        default:
                return false;
        }
}

static bool spt_port_hotplug_long_detect(enum port port, u32 val)
{
        switch (port) {
        case PORT_A:
                return val & PORTA_HOTPLUG_LONG_DETECT;
        case PORT_B:
                return val & PORTB_HOTPLUG_LONG_DETECT;
        case PORT_C:
                return val & PORTC_HOTPLUG_LONG_DETECT;
        case PORT_D:
                return val & PORTD_HOTPLUG_LONG_DETECT;
        default:
                return false;
        }
}

static bool ilk_port_hotplug_long_detect(enum port port, u32 val)
{
        switch (port) {
        case PORT_A:
                return val & DIGITAL_PORTA_HOTPLUG_LONG_DETECT;
        default:
                return false;
        }
}

static bool pch_port_hotplug_long_detect(enum port port, u32 val)
{
        switch (port) {
        case PORT_B:
                return val & PORTB_HOTPLUG_LONG_DETECT;
        case PORT_C:
                return val & PORTC_HOTPLUG_LONG_DETECT;
        case PORT_D:
                return val & PORTD_HOTPLUG_LONG_DETECT;
        default:
                return false;
        }
}

static bool i9xx_port_hotplug_long_detect(enum port port, u32 val)
{
        switch (port) {
        case PORT_B:
                return val & PORTB_HOTPLUG_INT_LONG_PULSE;
        case PORT_C:
                return val & PORTC_HOTPLUG_INT_LONG_PULSE;
        case PORT_D:
                return val & PORTD_HOTPLUG_INT_LONG_PULSE;
        default:
                return false;
        }
}

/*
 * Get a bit mask of pins that have triggered, and which ones may be long.
 * This can be called multiple times with the same masks to accumulate
 * hotplug detection results from several registers.
 *
 * Note that the caller is expected to zero out the masks initially.
 */
static void intel_get_hpd_pins(u32 *pin_mask, u32 *long_mask,
                             u32 hotplug_trigger, u32 dig_hotplug_reg,
                             const u32 hpd[HPD_NUM_PINS],
                             bool long_pulse_detect(enum port port, u32 val))
{
        enum port port;
        int i;

        for_each_hpd_pin(i) {
                if ((hpd[i] & hotplug_trigger) == 0)
                        continue;

                *pin_mask |= BIT(i);

                port = intel_hpd_pin_to_port(i);
                if (port == PORT_NONE)
                        continue;

                if (long_pulse_detect(port, dig_hotplug_reg))
                        *long_mask |= BIT(i);
        }

        DRM_DEBUG_DRIVER("hotplug event received, stat 0x%08x, dig 0x%08x, pins 0x%08x\n",
                         hotplug_trigger, dig_hotplug_reg, *pin_mask);

}

static void gmbus_irq_handler(struct drm_i915_private *dev_priv)
{
        wake_up_all(&dev_priv->gmbus_wait_queue);
}

static void dp_aux_irq_handler(struct drm_i915_private *dev_priv)
{
        wake_up_all(&dev_priv->gmbus_wait_queue);
}

#if defined(CONFIG_DEBUG_FS)
static void display_pipe_crc_irq_handler(struct drm_i915_private *dev_priv,
                                         enum pipe pipe,
                                         uint32_t crc0, uint32_t crc1,
                                         uint32_t crc2, uint32_t crc3,
                                         uint32_t crc4)
{
        struct intel_pipe_crc *pipe_crc = &dev_priv->pipe_crc[pipe];
        struct intel_pipe_crc_entry *entry;
        struct intel_crtc *crtc = intel_get_crtc_for_pipe(dev_priv, pipe);
        struct drm_driver *driver = dev_priv->drm.driver;
        uint32_t crcs[5];
        int head, tail;

        spin_lock(&pipe_crc->lock);
        if (pipe_crc->source) {
                if (!pipe_crc->entries) {
                        spin_unlock(&pipe_crc->lock);
                        DRM_DEBUG_KMS("spurious interrupt\n");
                        return;
                }

                head = pipe_crc->head;
                tail = pipe_crc->tail;

                if (CIRC_SPACE(head, tail, INTEL_PIPE_CRC_ENTRIES_NR) < 1) {
                        spin_unlock(&pipe_crc->lock);
                        DRM_ERROR("CRC buffer overflowing\n");
                        return;
                }

                entry = &pipe_crc->entries[head];

                entry->frame = driver->get_vblank_counter(&dev_priv->drm, pipe);
                entry->crc[0] = crc0;
                entry->crc[1] = crc1;
                entry->crc[2] = crc2;
                entry->crc[3] = crc3;
                entry->crc[4] = crc4;

                head = (head + 1) & (INTEL_PIPE_CRC_ENTRIES_NR - 1);
                pipe_crc->head = head;

                spin_unlock(&pipe_crc->lock);

                wake_up_interruptible(&pipe_crc->wq);
        } else {
                /*
                 * For some not yet identified reason, the first CRC is
                 * bonkers. So let's just wait for the next vblank and read
                 * out the buggy result.
                 *
                 * On CHV sometimes the second CRC is bonkers as well, so
                 * don't trust that one either.
                 */
                if (pipe_crc->skipped == 0 ||
                    (IS_CHERRYVIEW(dev_priv) && pipe_crc->skipped == 1)) {
                        pipe_crc->skipped++;
                        spin_unlock(&pipe_crc->lock);
                        return;
                }
                spin_unlock(&pipe_crc->lock);
                crcs[0] = crc0;
                crcs[1] = crc1;
                crcs[2] = crc2;
                crcs[3] = crc3;
                crcs[4] = crc4;
                drm_crtc_add_crc_entry(&crtc->base, true,
                                       drm_crtc_accurate_vblank_count(&crtc->base),
                                       crcs);
        }
}
#else
static inline void
display_pipe_crc_irq_handler(struct drm_i915_private *dev_priv,
                             enum pipe pipe,
                             uint32_t crc0, uint32_t crc1,
                             uint32_t crc2, uint32_t crc3,
                             uint32_t crc4) {}
#endif


static void hsw_pipe_crc_irq_handler(struct drm_i915_private *dev_priv,
                                     enum pipe pipe)
{
        display_pipe_crc_irq_handler(dev_priv, pipe,
                                     I915_READ(PIPE_CRC_RES_1_IVB(pipe)),
                                     0, 0, 0, 0);
}

static void ivb_pipe_crc_irq_handler(struct drm_i915_private *dev_priv,
                                     enum pipe pipe)
{
        display_pipe_crc_irq_handler(dev_priv, pipe,
                                     I915_READ(PIPE_CRC_RES_1_IVB(pipe)),
                                     I915_READ(PIPE_CRC_RES_2_IVB(pipe)),
                                     I915_READ(PIPE_CRC_RES_3_IVB(pipe)),
                                     I915_READ(PIPE_CRC_RES_4_IVB(pipe)),
                                     I915_READ(PIPE_CRC_RES_5_IVB(pipe)));
}

static void i9xx_pipe_crc_irq_handler(struct drm_i915_private *dev_priv,
                                      enum pipe pipe)
{
        uint32_t res1, res2;

        if (INTEL_GEN(dev_priv) >= 3)
                res1 = I915_READ(PIPE_CRC_RES_RES1_I915(pipe));
        else
                res1 = 0;

        if (INTEL_GEN(dev_priv) >= 5 || IS_G4X(dev_priv))
                res2 = I915_READ(PIPE_CRC_RES_RES2_G4X(pipe));
        else
                res2 = 0;

        display_pipe_crc_irq_handler(dev_priv, pipe,
                                     I915_READ(PIPE_CRC_RES_RED(pipe)),
                                     I915_READ(PIPE_CRC_RES_GREEN(pipe)),
                                     I915_READ(PIPE_CRC_RES_BLUE(pipe)),
                                     res1, res2);
}

/* The RPS events need forcewake, so we add them to a work queue and mask their
 * IMR bits until the work is done. Other interrupts can be processed without
 * the work queue. */
static void gen6_rps_irq_handler(struct drm_i915_private *dev_priv, u32 pm_iir)
{
        if (pm_iir & dev_priv->pm_rps_events) {
                spin_lock(&dev_priv->irq_lock);
                gen6_mask_pm_irq(dev_priv, pm_iir & dev_priv->pm_rps_events);
                if (dev_priv->rps.interrupts_enabled) {
                        dev_priv->rps.pm_iir |= pm_iir & dev_priv->pm_rps_events;
                        schedule_work(&dev_priv->rps.work);
                }
                spin_unlock(&dev_priv->irq_lock);
        }

        if (INTEL_GEN(dev_priv) >= 8)
                return;

        if (HAS_VEBOX(dev_priv)) {
                if (pm_iir & PM_VEBOX_USER_INTERRUPT)
                        notify_ring(dev_priv->engine[VECS]);

                if (pm_iir & PM_VEBOX_CS_ERROR_INTERRUPT)
                        DRM_DEBUG("Command parser error, pm_iir 0x%08x\n", pm_iir);
        }
}

static void gen9_guc_irq_handler(struct drm_i915_private *dev_priv, u32 gt_iir)
{
        if (gt_iir & GEN9_GUC_TO_HOST_INT_EVENT) {
                /* Sample the log buffer flush related bits & clear them out now
                 * itself from the message identity register to minimize the
                 * probability of losing a flush interrupt, when there are back
                 * to back flush interrupts.
                 * There can be a new flush interrupt, for different log buffer
                 * type (like for ISR), whilst Host is handling one (for DPC).
                 * Since same bit is used in message register for ISR & DPC, it
                 * could happen that GuC sets the bit for 2nd interrupt but Host
                 * clears out the bit on handling the 1st interrupt.
                 */
                u32 msg, flush;

                msg = I915_READ(SOFT_SCRATCH(15));
                flush = msg & (INTEL_GUC_RECV_MSG_CRASH_DUMP_POSTED |
                               INTEL_GUC_RECV_MSG_FLUSH_LOG_BUFFER);
                if (flush) {
                        /* Clear the message bits that are handled */
                        I915_WRITE(SOFT_SCRATCH(15), msg & ~flush);

                        /* Handle flush interrupt in bottom half */
                        queue_work(dev_priv->guc.log.runtime.flush_wq,
                                   &dev_priv->guc.log.runtime.flush_work);

                        dev_priv->guc.log.flush_interrupt_count++;
                } else {
                        /* Not clearing of unhandled event bits won't result in
                         * re-triggering of the interrupt.
                         */
                }
        }
}

static void valleyview_pipestat_irq_ack(struct drm_i915_private *dev_priv,
                                        u32 iir, u32 pipe_stats[I915_MAX_PIPES])
{
        int pipe;

        spin_lock(&dev_priv->irq_lock);

        if (!dev_priv->display_irqs_enabled) {
                spin_unlock(&dev_priv->irq_lock);
                return;
        }

        for_each_pipe(dev_priv, pipe) {
                i915_reg_t reg;
                u32 mask, iir_bit = 0;

                /*
                 * PIPESTAT bits get signalled even when the interrupt is
                 * disabled with the mask bits, and some of the status bits do
                 * not generate interrupts at all (like the underrun bit). Hence
                 * we need to be careful that we only handle what we want to
                 * handle.
                 */

                /* fifo underruns are filterered in the underrun handler. */
                mask = PIPE_FIFO_UNDERRUN_STATUS;

                switch (pipe) {
                case PIPE_A:
                        iir_bit = I915_DISPLAY_PIPE_A_EVENT_INTERRUPT;
                        break;
                case PIPE_B:
                        iir_bit = I915_DISPLAY_PIPE_B_EVENT_INTERRUPT;
                        break;
                case PIPE_C:
                        iir_bit = I915_DISPLAY_PIPE_C_EVENT_INTERRUPT;
                        break;
                }
                if (iir & iir_bit)
                        mask |= dev_priv->pipestat_irq_mask[pipe];

                if (!mask)
                        continue;

                reg = PIPESTAT(pipe);
                mask |= PIPESTAT_INT_ENABLE_MASK;
                pipe_stats[pipe] = I915_READ(reg) & mask;

                /*
                 * Clear the PIPE*STAT regs before the IIR
                 */
                if (pipe_stats[pipe] & (PIPE_FIFO_UNDERRUN_STATUS |
                                        PIPESTAT_INT_STATUS_MASK))
                        I915_WRITE(reg, pipe_stats[pipe]);
        }
        spin_unlock(&dev_priv->irq_lock);
}

static void valleyview_pipestat_irq_handler(struct drm_i915_private *dev_priv,
                                            u32 pipe_stats[I915_MAX_PIPES])
{
        enum pipe pipe;

        for_each_pipe(dev_priv, pipe) {
                if (pipe_stats[pipe] & PIPE_START_VBLANK_INTERRUPT_STATUS)
                        drm_handle_vblank(&dev_priv->drm, pipe);

                if (pipe_stats[pipe] & PIPE_CRC_DONE_INTERRUPT_STATUS)
                        i9xx_pipe_crc_irq_handler(dev_priv, pipe);

                if (pipe_stats[pipe] & PIPE_FIFO_UNDERRUN_STATUS)
                        intel_cpu_fifo_underrun_irq_handler(dev_priv, pipe);
        }

        if (pipe_stats[0] & PIPE_GMBUS_INTERRUPT_STATUS)
                gmbus_irq_handler(dev_priv);
}

static u32 i9xx_hpd_irq_ack(struct drm_i915_private *dev_priv)
{
        u32 hotplug_status = I915_READ(PORT_HOTPLUG_STAT);

        if (hotplug_status)
                I915_WRITE(PORT_HOTPLUG_STAT, hotplug_status);

        return hotplug_status;
}

static void i9xx_hpd_irq_handler(struct drm_i915_private *dev_priv,
                                 u32 hotplug_status)
{
        u32 pin_mask = 0, long_mask = 0;

        if (IS_G4X(dev_priv) || IS_VALLEYVIEW(dev_priv) ||
            IS_CHERRYVIEW(dev_priv)) {
                u32 hotplug_trigger = hotplug_status & HOTPLUG_INT_STATUS_G4X;

                if (hotplug_trigger) {
                        intel_get_hpd_pins(&pin_mask, &long_mask, hotplug_trigger,
                                           hotplug_trigger, hpd_status_g4x,
                                           i9xx_port_hotplug_long_detect);

                        intel_hpd_irq_handler(dev_priv, pin_mask, long_mask);
                }

                if (hotplug_status & DP_AUX_CHANNEL_MASK_INT_STATUS_G4X)
                        dp_aux_irq_handler(dev_priv);
        } else {
                u32 hotplug_trigger = hotplug_status & HOTPLUG_INT_STATUS_I915;

                if (hotplug_trigger) {
                        intel_get_hpd_pins(&pin_mask, &long_mask, hotplug_trigger,
                                           hotplug_trigger, hpd_status_i915,
                                           i9xx_port_hotplug_long_detect);
                        intel_hpd_irq_handler(dev_priv, pin_mask, long_mask);
                }
        }
}

static irqreturn_t valleyview_irq_handler(int irq, void *arg)
{
        struct drm_device *dev = arg;
        struct drm_i915_private *dev_priv = to_i915(dev);
        irqreturn_t ret = IRQ_NONE;

        if (!intel_irqs_enabled(dev_priv))
                return IRQ_NONE;

        /* IRQs are synced during runtime_suspend, we don't require a wakeref */
        disable_rpm_wakeref_asserts(dev_priv);

        do {
                u32 iir, gt_iir, pm_iir;
                u32 pipe_stats[I915_MAX_PIPES] = {};
                u32 hotplug_status = 0;
                u32 ier = 0;

                gt_iir = I915_READ(GTIIR);
                pm_iir = I915_READ(GEN6_PMIIR);
                iir = I915_READ(VLV_IIR);

                if (gt_iir == 0 && pm_iir == 0 && iir == 0)
                        break;

                ret = IRQ_HANDLED;

                /*
                 * Theory on interrupt generation, based on empirical evidence:
                 *
                 * x = ((VLV_IIR & VLV_IER) ||
                 *      (((GT_IIR & GT_IER) || (GEN6_PMIIR & GEN6_PMIER)) &&
                 *       (VLV_MASTER_IER & MASTER_INTERRUPT_ENABLE)));
                 *
                 * A CPU interrupt will only be raised when 'x' has a 0->1 edge.
                 * Hence we clear MASTER_INTERRUPT_ENABLE and VLV_IER to
                 * guarantee the CPU interrupt will be raised again even if we
                 * don't end up clearing all the VLV_IIR, GT_IIR, GEN6_PMIIR
                 * bits this time around.
                 */
                I915_WRITE(VLV_MASTER_IER, 0);
                ier = I915_READ(VLV_IER);
                I915_WRITE(VLV_IER, 0);

                if (gt_iir)
                        I915_WRITE(GTIIR, gt_iir);
                if (pm_iir)
                        I915_WRITE(GEN6_PMIIR, pm_iir);

                if (iir & I915_DISPLAY_PORT_INTERRUPT)
                        hotplug_status = i9xx_hpd_irq_ack(dev_priv);

                /* Call regardless, as some status bits might not be
                 * signalled in iir */
                valleyview_pipestat_irq_ack(dev_priv, iir, pipe_stats);

                if (iir & (I915_LPE_PIPE_A_INTERRUPT |
                           I915_LPE_PIPE_B_INTERRUPT))
                        intel_lpe_audio_irq_handler(dev_priv);

                /*
                 * VLV_IIR is single buffered, and reflects the level
                 * from PIPESTAT/PORT_HOTPLUG_STAT, hence clear it last.
                 */
                if (iir)
                        I915_WRITE(VLV_IIR, iir);

                I915_WRITE(VLV_IER, ier);
                I915_WRITE(VLV_MASTER_IER, MASTER_INTERRUPT_ENABLE);
                POSTING_READ(VLV_MASTER_IER);

                if (gt_iir)
                        snb_gt_irq_handler(dev_priv, gt_iir);
                if (pm_iir)
                        gen6_rps_irq_handler(dev_priv, pm_iir);

                if (hotplug_status)
                        i9xx_hpd_irq_handler(dev_priv, hotplug_status);

                valleyview_pipestat_irq_handler(dev_priv, pipe_stats);
        } while (0);

        enable_rpm_wakeref_asserts(dev_priv);

        return ret;
}

static irqreturn_t cherryview_irq_handler(int irq, void *arg)
{
        struct drm_device *dev = arg;
        struct drm_i915_private *dev_priv = to_i915(dev);
        irqreturn_t ret = IRQ_NONE;

        if (!intel_irqs_enabled(dev_priv))
                return IRQ_NONE;

        /* IRQs are synced during runtime_suspend, we don't require a wakeref */
        disable_rpm_wakeref_asserts(dev_priv);

        do {
                u32 master_ctl, iir;
                u32 gt_iir[4] = {};
                u32 pipe_stats[I915_MAX_PIPES] = {};
                u32 hotplug_status = 0;
                u32 ier = 0;

                master_ctl = I915_READ(GEN8_MASTER_IRQ) & ~GEN8_MASTER_IRQ_CONTROL;
                iir = I915_READ(VLV_IIR);

                if (master_ctl == 0 && iir == 0)
                        break;

                ret = IRQ_HANDLED;

                /*
                 * Theory on interrupt generation, based on empirical evidence:
                 *
                 * x = ((VLV_IIR & VLV_IER) ||
                 *      ((GEN8_MASTER_IRQ & ~GEN8_MASTER_IRQ_CONTROL) &&
                 *       (GEN8_MASTER_IRQ & GEN8_MASTER_IRQ_CONTROL)));
                 *
                 * A CPU interrupt will only be raised when 'x' has a 0->1 edge.
                 * Hence we clear GEN8_MASTER_IRQ_CONTROL and VLV_IER to
                 * guarantee the CPU interrupt will be raised again even if we
                 * don't end up clearing all the VLV_IIR and GEN8_MASTER_IRQ_CONTROL
                 * bits this time around.
                 */
                I915_WRITE(GEN8_MASTER_IRQ, 0);
                ier = I915_READ(VLV_IER);
                I915_WRITE(VLV_IER, 0);

                gen8_gt_irq_ack(dev_priv, master_ctl, gt_iir);

                if (iir & I915_DISPLAY_PORT_INTERRUPT)
                        hotplug_status = i9xx_hpd_irq_ack(dev_priv);

                /* Call regardless, as some status bits might not be
                 * signalled in iir */
                valleyview_pipestat_irq_ack(dev_priv, iir, pipe_stats);

                if (iir & (I915_LPE_PIPE_A_INTERRUPT |
                           I915_LPE_PIPE_B_INTERRUPT |
                           I915_LPE_PIPE_C_INTERRUPT))
                        intel_lpe_audio_irq_handler(dev_priv);

                /*
                 * VLV_IIR is single buffered, and reflects the level
                 * from PIPESTAT/PORT_HOTPLUG_STAT, hence clear it last.
                 */
                if (iir)
                        I915_WRITE(VLV_IIR, iir);

                I915_WRITE(VLV_IER, ier);
                I915_WRITE(GEN8_MASTER_IRQ, GEN8_MASTER_IRQ_CONTROL);
                POSTING_READ(GEN8_MASTER_IRQ);

                gen8_gt_irq_handler(dev_priv, gt_iir);

                if (hotplug_status)
                        i9xx_hpd_irq_handler(dev_priv, hotplug_status);

                valleyview_pipestat_irq_handler(dev_priv, pipe_stats);
        } while (0);

        enable_rpm_wakeref_asserts(dev_priv);

        return ret;
}

static void ibx_hpd_irq_handler(struct drm_i915_private *dev_priv,
                                u32 hotplug_trigger,
                                const u32 hpd[HPD_NUM_PINS])
{

        u32 dig_hotplug_reg, pin_mask = 0, long_mask = 0;

        /*
         * Somehow the PCH doesn't seem to really ack the interrupt to the CPU
         * unless we touch the hotplug register, even if hotplug_trigger is
         * zero. Not acking leads to "The master control interrupt lied (SDE)!"
         * errors.
         */
        dig_hotplug_reg = I915_READ(PCH_PORT_HOTPLUG);
        if (!hotplug_trigger) {
                u32 mask = PORTA_HOTPLUG_STATUS_MASK |
                        PORTD_HOTPLUG_STATUS_MASK |
                        PORTC_HOTPLUG_STATUS_MASK |
                        PORTB_HOTPLUG_STATUS_MASK;
                dig_hotplug_reg &= ~mask;
        }

        I915_WRITE(PCH_PORT_HOTPLUG, dig_hotplug_reg);
        if (!hotplug_trigger)
                return;

        intel_get_hpd_pins(&pin_mask, &long_mask, hotplug_trigger,
                           dig_hotplug_reg, hpd,
                           pch_port_hotplug_long_detect);

        intel_hpd_irq_handler(dev_priv, pin_mask, long_mask);
}

static void ibx_irq_handler(struct drm_i915_private *dev_priv, u32 pch_iir)
{
        int pipe;
        u32 hotplug_trigger = pch_iir & SDE_HOTPLUG_MASK;

        ibx_hpd_irq_handler(dev_priv, hotplug_trigger, hpd_ibx);

        if (pch_iir & SDE_AUDIO_POWER_MASK) {
                int port = ffs((pch_iir & SDE_AUDIO_POWER_MASK) >>
                               SDE_AUDIO_POWER_SHIFT);
                DRM_DEBUG_DRIVER("PCH audio power change on port %d\n",
                                 port_name(port));
        }

        if (pch_iir & SDE_AUX_MASK)
                dp_aux_irq_handler(dev_priv);

        if (pch_iir & SDE_GMBUS)
                gmbus_irq_handler(dev_priv);

        if (pch_iir & SDE_AUDIO_HDCP_MASK)
                DRM_DEBUG_DRIVER("PCH HDCP audio interrupt\n");

        if (pch_iir & SDE_AUDIO_TRANS_MASK)
                DRM_DEBUG_DRIVER("PCH transcoder audio interrupt\n");

        if (pch_iir & SDE_POISON)
                DRM_ERROR("PCH poison interrupt\n");

        if (pch_iir & SDE_FDI_MASK)
                for_each_pipe(dev_priv, pipe)
                        DRM_DEBUG_DRIVER("  pipe %c FDI IIR: 0x%08x\n",
                                         pipe_name(pipe),
                                         I915_READ(FDI_RX_IIR(pipe)));

        if (pch_iir & (SDE_TRANSB_CRC_DONE | SDE_TRANSA_CRC_DONE))
                DRM_DEBUG_DRIVER("PCH transcoder CRC done interrupt\n");

        if (pch_iir & (SDE_TRANSB_CRC_ERR | SDE_TRANSA_CRC_ERR))
                DRM_DEBUG_DRIVER("PCH transcoder CRC error interrupt\n");

        if (pch_iir & SDE_TRANSA_FIFO_UNDER)
                intel_pch_fifo_underrun_irq_handler(dev_priv, PIPE_A);

        if (pch_iir & SDE_TRANSB_FIFO_UNDER)
                intel_pch_fifo_underrun_irq_handler(dev_priv, PIPE_B);
}

static void ivb_err_int_handler(struct drm_i915_private *dev_priv)
{
        u32 err_int = I915_READ(GEN7_ERR_INT);
        enum pipe pipe;

        if (err_int & ERR_INT_POISON)
                DRM_ERROR("Poison interrupt\n");

        for_each_pipe(dev_priv, pipe) {
                if (err_int & ERR_INT_FIFO_UNDERRUN(pipe))
                        intel_cpu_fifo_underrun_irq_handler(dev_priv, pipe);

                if (err_int & ERR_INT_PIPE_CRC_DONE(pipe)) {
                        if (IS_IVYBRIDGE(dev_priv))
                                ivb_pipe_crc_irq_handler(dev_priv, pipe);
                        else
                                hsw_pipe_crc_irq_handler(dev_priv, pipe);
                }
        }

        I915_WRITE(GEN7_ERR_INT, err_int);
}

static void cpt_serr_int_handler(struct drm_i915_private *dev_priv)
{
        u32 serr_int = I915_READ(SERR_INT);

        if (serr_int & SERR_INT_POISON)
                DRM_ERROR("PCH poison interrupt\n");

        if (serr_int & SERR_INT_TRANS_A_FIFO_UNDERRUN)
                intel_pch_fifo_underrun_irq_handler(dev_priv, PIPE_A);

        if (serr_int & SERR_INT_TRANS_B_FIFO_UNDERRUN)
                intel_pch_fifo_underrun_irq_handler(dev_priv, PIPE_B);

        if (serr_int & SERR_INT_TRANS_C_FIFO_UNDERRUN)
                intel_pch_fifo_underrun_irq_handler(dev_priv, PIPE_C);

        I915_WRITE(SERR_INT, serr_int);
}

static void cpt_irq_handler(struct drm_i915_private *dev_priv, u32 pch_iir)
{
        int pipe;
        u32 hotplug_trigger = pch_iir & SDE_HOTPLUG_MASK_CPT;

        ibx_hpd_irq_handler(dev_priv, hotplug_trigger, hpd_cpt);

        if (pch_iir & SDE_AUDIO_POWER_MASK_CPT) {
                int port = ffs((pch_iir & SDE_AUDIO_POWER_MASK_CPT) >>
                               SDE_AUDIO_POWER_SHIFT_CPT);
                DRM_DEBUG_DRIVER("PCH audio power change on port %c\n",
                                 port_name(port));
        }

        if (pch_iir & SDE_AUX_MASK_CPT)
                dp_aux_irq_handler(dev_priv);

        if (pch_iir & SDE_GMBUS_CPT)
                gmbus_irq_handler(dev_priv);

        if (pch_iir & SDE_AUDIO_CP_REQ_CPT)
                DRM_DEBUG_DRIVER("Audio CP request interrupt\n");

        if (pch_iir & SDE_AUDIO_CP_CHG_CPT)
                DRM_DEBUG_DRIVER("Audio CP change interrupt\n");

        if (pch_iir & SDE_FDI_MASK_CPT)
                for_each_pipe(dev_priv, pipe)
                        DRM_DEBUG_DRIVER("  pipe %c FDI IIR: 0x%08x\n",
                                         pipe_name(pipe),
                                         I915_READ(FDI_RX_IIR(pipe)));

        if (pch_iir & SDE_ERROR_CPT)
                cpt_serr_int_handler(dev_priv);
}

static void spt_irq_handler(struct drm_i915_private *dev_priv, u32 pch_iir)
{
        u32 hotplug_trigger = pch_iir & SDE_HOTPLUG_MASK_SPT &
                ~SDE_PORTE_HOTPLUG_SPT;
        u32 hotplug2_trigger = pch_iir & SDE_PORTE_HOTPLUG_SPT;
        u32 pin_mask = 0, long_mask = 0;

        if (hotplug_trigger) {
                u32 dig_hotplug_reg;

                dig_hotplug_reg = I915_READ(PCH_PORT_HOTPLUG);
                I915_WRITE(PCH_PORT_HOTPLUG, dig_hotplug_reg);

                intel_get_hpd_pins(&pin_mask, &long_mask, hotplug_trigger,
                                   dig_hotplug_reg, hpd_spt,
                                   spt_port_hotplug_long_detect);
        }

        if (hotplug2_trigger) {
                u32 dig_hotplug_reg;

                dig_hotplug_reg = I915_READ(PCH_PORT_HOTPLUG2);
                I915_WRITE(PCH_PORT_HOTPLUG2, dig_hotplug_reg);

                intel_get_hpd_pins(&pin_mask, &long_mask, hotplug2_trigger,
                                   dig_hotplug_reg, hpd_spt,
                                   spt_port_hotplug2_long_detect);
        }

        if (pin_mask)
                intel_hpd_irq_handler(dev_priv, pin_mask, long_mask);

        if (pch_iir & SDE_GMBUS_CPT)
                gmbus_irq_handler(dev_priv);
}

static void ilk_hpd_irq_handler(struct drm_i915_private *dev_priv,
                                u32 hotplug_trigger,
                                const u32 hpd[HPD_NUM_PINS])
{
        u32 dig_hotplug_reg, pin_mask = 0, long_mask = 0;

        dig_hotplug_reg = I915_READ(DIGITAL_PORT_HOTPLUG_CNTRL);
        I915_WRITE(DIGITAL_PORT_HOTPLUG_CNTRL, dig_hotplug_reg);

        intel_get_hpd_pins(&pin_mask, &long_mask, hotplug_trigger,
                           dig_hotplug_reg, hpd,
                           ilk_port_hotplug_long_detect);

        intel_hpd_irq_handler(dev_priv, pin_mask, long_mask);
}

static void ilk_display_irq_handler(struct drm_i915_private *dev_priv,
                                    u32 de_iir)
{
        enum pipe pipe;
        u32 hotplug_trigger = de_iir & DE_DP_A_HOTPLUG;

        if (hotplug_trigger)
                ilk_hpd_irq_handler(dev_priv, hotplug_trigger, hpd_ilk);

        if (de_iir & DE_AUX_CHANNEL_A)
                dp_aux_irq_handler(dev_priv);

        if (de_iir & DE_GSE)
                intel_opregion_asle_intr(dev_priv);

        if (de_iir & DE_POISON)
                DRM_ERROR("Poison interrupt\n");

        for_each_pipe(dev_priv, pipe) {
                if (de_iir & DE_PIPE_VBLANK(pipe))
                        drm_handle_vblank(&dev_priv->drm, pipe);

                if (de_iir & DE_PIPE_FIFO_UNDERRUN(pipe))
                        intel_cpu_fifo_underrun_irq_handler(dev_priv, pipe);

                if (de_iir & DE_PIPE_CRC_DONE(pipe))
                        i9xx_pipe_crc_irq_handler(dev_priv, pipe);
        }

        /* check event from PCH */
        if (de_iir & DE_PCH_EVENT) {
                u32 pch_iir = I915_READ(SDEIIR);

                if (HAS_PCH_CPT(dev_priv))
                        cpt_irq_handler(dev_priv, pch_iir);
                else
                        ibx_irq_handler(dev_priv, pch_iir);

                /* should clear PCH hotplug event before clear CPU irq */
                I915_WRITE(SDEIIR, pch_iir);
        }

        if (IS_GEN5(dev_priv) && de_iir & DE_PCU_EVENT)
                ironlake_rps_change_irq_handler(dev_priv);
}

static void ivb_display_irq_handler(struct drm_i915_private *dev_priv,
                                    u32 de_iir)
{
        enum pipe pipe;
        u32 hotplug_trigger = de_iir & DE_DP_A_HOTPLUG_IVB;

        if (hotplug_trigger)
                ilk_hpd_irq_handler(dev_priv, hotplug_trigger, hpd_ivb);

        if (de_iir & DE_ERR_INT_IVB)
                ivb_err_int_handler(dev_priv);

        if (de_iir & DE_AUX_CHANNEL_A_IVB)
                dp_aux_irq_handler(dev_priv);

        if (de_iir & DE_GSE_IVB)
                intel_opregion_asle_intr(dev_priv);

        for_each_pipe(dev_priv, pipe) {
                if (de_iir & (DE_PIPE_VBLANK_IVB(pipe)))
                        drm_handle_vblank(&dev_priv->drm, pipe);
        }

        /* check event from PCH */
        if (!HAS_PCH_NOP(dev_priv) && (de_iir & DE_PCH_EVENT_IVB)) {
                u32 pch_iir = I915_READ(SDEIIR);

                cpt_irq_handler(dev_priv, pch_iir);

                /* clear PCH hotplug event before clear CPU irq */
                I915_WRITE(SDEIIR, pch_iir);
        }
}

/*
 * To handle irqs with the minimum potential races with fresh interrupts, we:
 * 1 - Disable Master Interrupt Control.
 * 2 - Find the source(s) of the interrupt.
 * 3 - Clear the Interrupt Identity bits (IIR).
 * 4 - Process the interrupt(s) that had bits set in the IIRs.
 * 5 - Re-enable Master Interrupt Control.
 */
static irqreturn_t ironlake_irq_handler(int irq, void *arg)
{
        struct drm_device *dev = arg;
        struct drm_i915_private *dev_priv = to_i915(dev);
        u32 de_iir, gt_iir, de_ier, sde_ier = 0;
        irqreturn_t ret = IRQ_NONE;

        if (!intel_irqs_enabled(dev_priv))
                return IRQ_NONE;

        /* IRQs are synced during runtime_suspend, we don't require a wakeref */
        disable_rpm_wakeref_asserts(dev_priv);

        /* disable master interrupt before clearing iir  */
        de_ier = I915_READ(DEIER);
        I915_WRITE(DEIER, de_ier & ~DE_MASTER_IRQ_CONTROL);
        POSTING_READ(DEIER);

        /* Disable south interrupts. We'll only write to SDEIIR once, so further
         * interrupts will will be stored on its back queue, and then we'll be
         * able to process them after we restore SDEIER (as soon as we restore
         * it, we'll get an interrupt if SDEIIR still has something to process
         * due to its back queue). */
        if (!HAS_PCH_NOP(dev_priv)) {
                sde_ier = I915_READ(SDEIER);
                I915_WRITE(SDEIER, 0);
                POSTING_READ(SDEIER);
        }

        /* Find, clear, then process each source of interrupt */

        gt_iir = I915_READ(GTIIR);
        if (gt_iir) {
                I915_WRITE(GTIIR, gt_iir);
                ret = IRQ_HANDLED;
                if (INTEL_GEN(dev_priv) >= 6)
                        snb_gt_irq_handler(dev_priv, gt_iir);
                else
                        ilk_gt_irq_handler(dev_priv, gt_iir);
        }

        de_iir = I915_READ(DEIIR);
        if (de_iir) {
                I915_WRITE(DEIIR, de_iir);
                ret = IRQ_HANDLED;
                if (INTEL_GEN(dev_priv) >= 7)
                        ivb_display_irq_handler(dev_priv, de_iir);
                else
                        ilk_display_irq_handler(dev_priv, de_iir);
        }

        if (INTEL_GEN(dev_priv) >= 6) {
                u32 pm_iir = I915_READ(GEN6_PMIIR);
                if (pm_iir) {
                        I915_WRITE(GEN6_PMIIR, pm_iir);
                        ret = IRQ_HANDLED;
                        gen6_rps_irq_handler(dev_priv, pm_iir);
                }
        }

        I915_WRITE(DEIER, de_ier);
        POSTING_READ(DEIER);
        if (!HAS_PCH_NOP(dev_priv)) {
                I915_WRITE(SDEIER, sde_ier);
                POSTING_READ(SDEIER);
        }

        /* IRQs are synced during runtime_suspend, we don't require a wakeref */
        enable_rpm_wakeref_asserts(dev_priv);

        return ret;
}

static void bxt_hpd_irq_handler(struct drm_i915_private *dev_priv,
                                u32 hotplug_trigger,
                                const u32 hpd[HPD_NUM_PINS])
{
        u32 dig_hotplug_reg, pin_mask = 0, long_mask = 0;

        dig_hotplug_reg = I915_READ(PCH_PORT_HOTPLUG);
        I915_WRITE(PCH_PORT_HOTPLUG, dig_hotplug_reg);

        intel_get_hpd_pins(&pin_mask, &long_mask, hotplug_trigger,
                           dig_hotplug_reg, hpd,
                           bxt_port_hotplug_long_detect);

        intel_hpd_irq_handler(dev_priv, pin_mask, long_mask);
}

static irqreturn_t
gen8_de_irq_handler(struct drm_i915_private *dev_priv, u32 master_ctl)
{
        irqreturn_t ret = IRQ_NONE;
        u32 iir;
        enum pipe pipe;

        if (master_ctl & GEN8_DE_MISC_IRQ) {
                iir = I915_READ(GEN8_DE_MISC_IIR);
                if (iir) {
                        I915_WRITE(GEN8_DE_MISC_IIR, iir);
                        ret = IRQ_HANDLED;
                        if (iir & GEN8_DE_MISC_GSE)
                                intel_opregion_asle_intr(dev_priv);
                        else
                                DRM_ERROR("Unexpected DE Misc interrupt\n");
                }
                else
                        DRM_ERROR("The master control interrupt lied (DE MISC)!\n");
        }

        if (master_ctl & GEN8_DE_PORT_IRQ) {
                iir = I915_READ(GEN8_DE_PORT_IIR);
                if (iir) {
                        u32 tmp_mask;
                        bool found = false;

                        I915_WRITE(GEN8_DE_PORT_IIR, iir);
                        ret = IRQ_HANDLED;

                        tmp_mask = GEN8_AUX_CHANNEL_A;
                        if (INTEL_GEN(dev_priv) >= 9)
                                tmp_mask |= GEN9_AUX_CHANNEL_B |
                                            GEN9_AUX_CHANNEL_C |
                                            GEN9_AUX_CHANNEL_D;

                        if (iir & tmp_mask) {
                                dp_aux_irq_handler(dev_priv);
                                found = true;
                        }

                        if (IS_GEN9_LP(dev_priv)) {
                                tmp_mask = iir & BXT_DE_PORT_HOTPLUG_MASK;
                                if (tmp_mask) {
                                        bxt_hpd_irq_handler(dev_priv, tmp_mask,
                                                            hpd_bxt);
                                        found = true;
                                }
                        } else if (IS_BROADWELL(dev_priv)) {
                                tmp_mask = iir & GEN8_PORT_DP_A_HOTPLUG;
                                if (tmp_mask) {
                                        ilk_hpd_irq_handler(dev_priv,
                                                            tmp_mask, hpd_bdw);
                                        found = true;
                                }
                        }

                        if (IS_GEN9_LP(dev_priv) && (iir & BXT_DE_PORT_GMBUS)) {
                                gmbus_irq_handler(dev_priv);
                                found = true;
                        }

                        if (!found)
                                DRM_ERROR("Unexpected DE Port interrupt\n");
                }
                else
                        DRM_ERROR("The master control interrupt lied (DE PORT)!\n");
        }

        for_each_pipe(dev_priv, pipe) {
                u32 fault_errors;

                if (!(master_ctl & GEN8_DE_PIPE_IRQ(pipe)))
                        continue;

                iir = I915_READ(GEN8_DE_PIPE_IIR(pipe));
                if (!iir) {
                        DRM_ERROR("The master control interrupt lied (DE PIPE)!\n");
                        continue;
                }

                ret = IRQ_HANDLED;
                I915_WRITE(GEN8_DE_PIPE_IIR(pipe), iir);

                if (iir & GEN8_PIPE_VBLANK)
                        drm_handle_vblank(&dev_priv->drm, pipe);

                if (iir & GEN8_PIPE_CDCLK_CRC_DONE)
                        hsw_pipe_crc_irq_handler(dev_priv, pipe);

                if (iir & GEN8_PIPE_FIFO_UNDERRUN)
                        intel_cpu_fifo_underrun_irq_handler(dev_priv, pipe);

                fault_errors = iir;
                if (INTEL_GEN(dev_priv) >= 9)
                        fault_errors &= GEN9_DE_PIPE_IRQ_FAULT_ERRORS;
                else
                        fault_errors &= GEN8_DE_PIPE_IRQ_FAULT_ERRORS;

                if (fault_errors)
                        DRM_ERROR("Fault errors on pipe %c: 0x%08x\n",
                                  pipe_name(pipe),
                                  fault_errors);
        }

        if (HAS_PCH_SPLIT(dev_priv) && !HAS_PCH_NOP(dev_priv) &&
            master_ctl & GEN8_DE_PCH_IRQ) {
                /*
                 * FIXME(BDW): Assume for now that the new interrupt handling
                 * scheme also closed the SDE interrupt handling race we've seen
                 * on older pch-split platforms. But this needs testing.
                 */
                iir = I915_READ(SDEIIR);
                if (iir) {
                        I915_WRITE(SDEIIR, iir);
                        ret = IRQ_HANDLED;

                        if (HAS_PCH_SPT(dev_priv) || HAS_PCH_KBP(dev_priv) ||
                            HAS_PCH_CNP(dev_priv))
                                spt_irq_handler(dev_priv, iir);
                        else
                                cpt_irq_handler(dev_priv, iir);
                } else {
                        /*
                         * Like on previous PCH there seems to be something
                         * fishy going on with forwarding PCH interrupts.
                         */
                        DRM_DEBUG_DRIVER("The master control interrupt lied (SDE)!\n");
                }
        }

        return ret;
}

static irqreturn_t gen8_irq_handler(int irq, void *arg)
{
        struct drm_device *dev = arg;
        struct drm_i915_private *dev_priv = to_i915(dev);
        u32 master_ctl;
        u32 gt_iir[4] = {};
        irqreturn_t ret;

        if (!intel_irqs_enabled(dev_priv))
                return IRQ_NONE;

        master_ctl = I915_READ_FW(GEN8_MASTER_IRQ);
        master_ctl &= ~GEN8_MASTER_IRQ_CONTROL;
        if (!master_ctl)
                return IRQ_NONE;

        I915_WRITE_FW(GEN8_MASTER_IRQ, 0);

        /* IRQs are synced during runtime_suspend, we don't require a wakeref */
        disable_rpm_wakeref_asserts(dev_priv);

        /* Find, clear, then process each source of interrupt */
        ret = gen8_gt_irq_ack(dev_priv, master_ctl, gt_iir);
        gen8_gt_irq_handler(dev_priv, gt_iir);
        ret |= gen8_de_irq_handler(dev_priv, master_ctl);

        I915_WRITE_FW(GEN8_MASTER_IRQ, GEN8_MASTER_IRQ_CONTROL);
        POSTING_READ_FW(GEN8_MASTER_IRQ);

        enable_rpm_wakeref_asserts(dev_priv);

        return ret;
}

struct wedge_me {
        struct delayed_work work;
        struct drm_i915_private *i915;
        const char *name;
};

static void wedge_me(struct work_struct *work)
{
        struct wedge_me *w = container_of(work, typeof(*w), work.work);

        dev_err(w->i915->drm.dev,
                "%s timed out, cancelling all in-flight rendering.\n",
                w->name);
        i915_gem_set_wedged(w->i915);
}

static void __init_wedge(struct wedge_me *w,
                         struct drm_i915_private *i915,
                         long timeout,
                         const char *name)
{
        w->i915 = i915;
        w->name = name;

        INIT_DELAYED_WORK_ONSTACK(&w->work, wedge_me);
        schedule_delayed_work(&w->work, timeout);
}

static void __fini_wedge(struct wedge_me *w)
{
        cancel_delayed_work_sync(&w->work);
        destroy_delayed_work_on_stack(&w->work);
        w->i915 = NULL;
}

#define i915_wedge_on_timeout(W, DEV, TIMEOUT)                          \
        for (__init_wedge((W), (DEV), (TIMEOUT), __func__);             \
             (W)->i915;                                                 \
             __fini_wedge((W)))

/**
 * i915_reset_device - do process context error handling work
 * @dev_priv: i915 device private
 *
 * Fire an error uevent so userspace can see that a hang or error
 * was detected.
 */
static void i915_reset_device(struct drm_i915_private *dev_priv)
{
        struct kobject *kobj = &dev_priv->drm.primary->kdev->kobj;
        char *error_event[] = { I915_ERROR_UEVENT "=1", NULL };
        char *reset_event[] = { I915_RESET_UEVENT "=1", NULL };
        char *reset_done_event[] = { I915_ERROR_UEVENT "=0", NULL };
        struct wedge_me w;

        kobject_uevent_env(kobj, KOBJ_CHANGE, error_event);

        DRM_DEBUG_DRIVER("resetting chip\n");
        kobject_uevent_env(kobj, KOBJ_CHANGE, reset_event);

        /* Use a watchdog to ensure that our reset completes */
        i915_wedge_on_timeout(&w, dev_priv, 5*HZ) {
                intel_prepare_reset(dev_priv);

                /* Signal that locked waiters should reset the GPU */
                set_bit(I915_RESET_HANDOFF, &dev_priv->gpu_error.flags);
                wake_up_all(&dev_priv->gpu_error.wait_queue);

                /* Wait for anyone holding the lock to wakeup, without
                 * blocking indefinitely on struct_mutex.
                 */
                do {
                        if (mutex_trylock(&dev_priv->drm.struct_mutex)) {
                                i915_reset(dev_priv, 0);
                                mutex_unlock(&dev_priv->drm.struct_mutex);
                        }
                } while (wait_on_bit_timeout(&dev_priv->gpu_error.flags,
                                             I915_RESET_HANDOFF,
                                             TASK_UNINTERRUPTIBLE,
                                             1));

                intel_finish_reset(dev_priv);
        }

        if (!test_bit(I915_WEDGED, &dev_priv->gpu_error.flags))
                kobject_uevent_env(kobj,
                                   KOBJ_CHANGE, reset_done_event);
}

static void i915_clear_error_registers(struct drm_i915_private *dev_priv)
{
        u32 eir;

        if (!IS_GEN2(dev_priv))
                I915_WRITE(PGTBL_ER, I915_READ(PGTBL_ER));

        if (INTEL_GEN(dev_priv) < 4)
                I915_WRITE(IPEIR, I915_READ(IPEIR));
        else
                I915_WRITE(IPEIR_I965, I915_READ(IPEIR_I965));

        I915_WRITE(EIR, I915_READ(EIR));
        eir = I915_READ(EIR);
        if (eir) {
                /*
                 * some errors might have become stuck,
                 * mask them.
                 */
                DRM_DEBUG_DRIVER("EIR stuck: 0x%08x, masking\n", eir);
                I915_WRITE(EMR, I915_READ(EMR) | eir);
                I915_WRITE(IIR, I915_RENDER_COMMAND_PARSER_ERROR_INTERRUPT);
        }
}

/**
 * i915_handle_error - handle a gpu error
 * @dev_priv: i915 device private
 * @engine_mask: mask representing engines that are hung
 * @fmt: Error message format string
 *
 * Do some basic checking of register state at error time and
 * dump it to the syslog.  Also call i915_capture_error_state() to make
 * sure we get a record and make it available in debugfs.  Fire a uevent
 * so userspace knows something bad happened (should trigger collection
 * of a ring dump etc.).
 */
void i915_handle_error(struct drm_i915_private *dev_priv,
                       u32 engine_mask,
                       const char *fmt, ...)
{
        struct intel_engine_cs *engine;
        unsigned int tmp;
        va_list args;
        char error_msg[80];

        va_start(args, fmt);
        vscnprintf(error_msg, sizeof(error_msg), fmt, args);
        va_end(args);

        /*
         * In most cases it's guaranteed that we get here with an RPM
         * reference held, for example because there is a pending GPU
         * request that won't finish until the reset is done. This
         * isn't the case at least when we get here by doing a
         * simulated reset via debugfs, so get an RPM reference.
         */
        intel_runtime_pm_get(dev_priv);

        i915_capture_error_state(dev_priv, engine_mask, error_msg);
        i915_clear_error_registers(dev_priv);

        /*
         * Try engine reset when available. We fall back to full reset if
         * single reset fails.
         */
        if (intel_has_reset_engine(dev_priv)) {
                for_each_engine_masked(engine, dev_priv, engine_mask, tmp) {
                        BUILD_BUG_ON(I915_RESET_MODESET >= I915_RESET_ENGINE);
                        if (test_and_set_bit(I915_RESET_ENGINE + engine->id,
                                             &dev_priv->gpu_error.flags))
                                continue;

                        if (i915_reset_engine(engine, 0) == 0)
                                engine_mask &= ~intel_engine_flag(engine);

                        clear_bit(I915_RESET_ENGINE + engine->id,
                                  &dev_priv->gpu_error.flags);
                        wake_up_bit(&dev_priv->gpu_error.flags,
                                    I915_RESET_ENGINE + engine->id);
                }
        }

        if (!engine_mask)
                goto out;

        /* Full reset needs the mutex, stop any other user trying to do so. */
        if (test_and_set_bit(I915_RESET_BACKOFF, &dev_priv->gpu_error.flags)) {
                wait_event(dev_priv->gpu_error.reset_queue,
                           !test_bit(I915_RESET_BACKOFF,
                                     &dev_priv->gpu_error.flags));
                goto out;
        }

        /* Prevent any other reset-engine attempt. */
        for_each_engine(engine, dev_priv, tmp) {
                while (test_and_set_bit(I915_RESET_ENGINE + engine->id,
                                        &dev_priv->gpu_error.flags))
                        wait_on_bit(&dev_priv->gpu_error.flags,
                                    I915_RESET_ENGINE + engine->id,
                                    TASK_UNINTERRUPTIBLE);
        }

        i915_reset_device(dev_priv);

        for_each_engine(engine, dev_priv, tmp) {
                clear_bit(I915_RESET_ENGINE + engine->id,
                          &dev_priv->gpu_error.flags);
        }

        clear_bit(I915_RESET_BACKOFF, &dev_priv->gpu_error.flags);
        wake_up_all(&dev_priv->gpu_error.reset_queue);

out:
        intel_runtime_pm_put(dev_priv);
}

/* Called from drm generic code, passed 'crtc' which
 * we use as a pipe index
 */
static int i8xx_enable_vblank(struct drm_device *dev, unsigned int pipe)
{
        struct drm_i915_private *dev_priv = to_i915(dev);
        unsigned long irqflags;

        spin_lock_irqsave(&dev_priv->irq_lock, irqflags);
        i915_enable_pipestat(dev_priv, pipe, PIPE_VBLANK_INTERRUPT_STATUS);
        spin_unlock_irqrestore(&dev_priv->irq_lock, irqflags);

        return 0;
}

static int i965_enable_vblank(struct drm_device *dev, unsigned int pipe)
{
        struct drm_i915_private *dev_priv = to_i915(dev);
        unsigned long irqflags;

        spin_lock_irqsave(&dev_priv->irq_lock, irqflags);
        i915_enable_pipestat(dev_priv, pipe,
                             PIPE_START_VBLANK_INTERRUPT_STATUS);
        spin_unlock_irqrestore(&dev_priv->irq_lock, irqflags);

        return 0;
}

static int ironlake_enable_vblank(struct drm_device *dev, unsigned int pipe)
{
        struct drm_i915_private *dev_priv = to_i915(dev);
        unsigned long irqflags;
        uint32_t bit = INTEL_GEN(dev_priv) >= 7 ?
                DE_PIPE_VBLANK_IVB(pipe) : DE_PIPE_VBLANK(pipe);

        spin_lock_irqsave(&dev_priv->irq_lock, irqflags);
        ilk_enable_display_irq(dev_priv, bit);
        spin_unlock_irqrestore(&dev_priv->irq_lock, irqflags);

        return 0;
}

static int gen8_enable_vblank(struct drm_device *dev, unsigned int pipe)
{
        struct drm_i915_private *dev_priv = to_i915(dev);
        unsigned long irqflags;

        spin_lock_irqsave(&dev_priv->irq_lock, irqflags);
        bdw_enable_pipe_irq(dev_priv, pipe, GEN8_PIPE_VBLANK);
        spin_unlock_irqrestore(&dev_priv->irq_lock, irqflags);

        return 0;
}

/* Called from drm generic code, passed 'crtc' which
 * we use as a pipe index
 */
static void i8xx_disable_vblank(struct drm_device *dev, unsigned int pipe)
{
        struct drm_i915_private *dev_priv = to_i915(dev);
        unsigned long irqflags;

        spin_lock_irqsave(&dev_priv->irq_lock, irqflags);
        i915_disable_pipestat(dev_priv, pipe, PIPE_VBLANK_INTERRUPT_STATUS);
        spin_unlock_irqrestore(&dev_priv->irq_lock, irqflags);
}

static void i965_disable_vblank(struct drm_device *dev, unsigned int pipe)
{
        struct drm_i915_private *dev_priv = to_i915(dev);
        unsigned long irqflags;

        spin_lock_irqsave(&dev_priv->irq_lock, irqflags);
        i915_disable_pipestat(dev_priv, pipe,
                              PIPE_START_VBLANK_INTERRUPT_STATUS);
        spin_unlock_irqrestore(&dev_priv->irq_lock, irqflags);
}

static void ironlake_disable_vblank(struct drm_device *dev, unsigned int pipe)
{
        struct drm_i915_private *dev_priv = to_i915(dev);
        unsigned long irqflags;
        uint32_t bit = INTEL_GEN(dev_priv) >= 7 ?
                DE_PIPE_VBLANK_IVB(pipe) : DE_PIPE_VBLANK(pipe);

        spin_lock_irqsave(&dev_priv->irq_lock, irqflags);
        ilk_disable_display_irq(dev_priv, bit);
        spin_unlock_irqrestore(&dev_priv->irq_lock, irqflags);
}

static void gen8_disable_vblank(struct drm_device *dev, unsigned int pipe)
{
        struct drm_i915_private *dev_priv = to_i915(dev);
        unsigned long irqflags;

        spin_lock_irqsave(&dev_priv->irq_lock, irqflags);
        bdw_disable_pipe_irq(dev_priv, pipe, GEN8_PIPE_VBLANK);
        spin_unlock_irqrestore(&dev_priv->irq_lock, irqflags);
}

static void ibx_irq_reset(struct drm_i915_private *dev_priv)
{
        if (HAS_PCH_NOP(dev_priv))
                return;

        GEN5_IRQ_RESET(SDE);

        if (HAS_PCH_CPT(dev_priv) || HAS_PCH_LPT(dev_priv))
                I915_WRITE(SERR_INT, 0xffffffff);
}

/*
 * SDEIER is also touched by the interrupt handler to work around missed PCH
 * interrupts. Hence we can't update it after the interrupt handler is enabled -
 * instead we unconditionally enable all PCH interrupt sources here, but then
 * only unmask them as needed with SDEIMR.
 *
 * This function needs to be called before interrupts are enabled.
 */
static void ibx_irq_pre_postinstall(struct drm_device *dev)
{
        struct drm_i915_private *dev_priv = to_i915(dev);

        if (HAS_PCH_NOP(dev_priv))
                return;

        WARN_ON(I915_READ(SDEIER) != 0);
        I915_WRITE(SDEIER, 0xffffffff);
        POSTING_READ(SDEIER);
}

static void gen5_gt_irq_reset(struct drm_i915_private *dev_priv)
{
        GEN5_IRQ_RESET(GT);
        if (INTEL_GEN(dev_priv) >= 6)
                GEN5_IRQ_RESET(GEN6_PM);
}

static void vlv_display_irq_reset(struct drm_i915_private *dev_priv)
{
        enum pipe pipe;

        if (IS_CHERRYVIEW(dev_priv))
                I915_WRITE(DPINVGTT, DPINVGTT_STATUS_MASK_CHV);
        else
                I915_WRITE(DPINVGTT, DPINVGTT_STATUS_MASK);

        i915_hotplug_interrupt_update_locked(dev_priv, 0xffffffff, 0);
        I915_WRITE(PORT_HOTPLUG_STAT, I915_READ(PORT_HOTPLUG_STAT));

        for_each_pipe(dev_priv, pipe) {
                I915_WRITE(PIPESTAT(pipe),
                           PIPE_FIFO_UNDERRUN_STATUS |
                           PIPESTAT_INT_STATUS_MASK);
                dev_priv->pipestat_irq_mask[pipe] = 0;
        }

        GEN5_IRQ_RESET(VLV_);
        dev_priv->irq_mask = ~0;
}

static void vlv_display_irq_postinstall(struct drm_i915_private *dev_priv)
{
        u32 pipestat_mask;
        u32 enable_mask;
        enum pipe pipe;

        pipestat_mask = PLANE_FLIP_DONE_INT_STATUS_VLV |
                        PIPE_CRC_DONE_INTERRUPT_STATUS;

        i915_enable_pipestat(dev_priv, PIPE_A, PIPE_GMBUS_INTERRUPT_STATUS);
        for_each_pipe(dev_priv, pipe)
                i915_enable_pipestat(dev_priv, pipe, pipestat_mask);

        enable_mask = I915_DISPLAY_PORT_INTERRUPT |
                I915_DISPLAY_PIPE_A_EVENT_INTERRUPT |
                I915_DISPLAY_PIPE_B_EVENT_INTERRUPT |
                I915_LPE_PIPE_A_INTERRUPT |
                I915_LPE_PIPE_B_INTERRUPT;

        if (IS_CHERRYVIEW(dev_priv))
                enable_mask |= I915_DISPLAY_PIPE_C_EVENT_INTERRUPT |
                        I915_LPE_PIPE_C_INTERRUPT;

        WARN_ON(dev_priv->irq_mask != ~0);

        dev_priv->irq_mask = ~enable_mask;

        GEN5_IRQ_INIT(VLV_, dev_priv->irq_mask, enable_mask);
}

/* drm_dma.h hooks
*/
static void ironlake_irq_reset(struct drm_device *dev)
{
        struct drm_i915_private *dev_priv = to_i915(dev);

        I915_WRITE(HWSTAM, 0xffffffff);

        GEN5_IRQ_RESET(DE);
        if (IS_GEN7(dev_priv))
                I915_WRITE(GEN7_ERR_INT, 0xffffffff);

        gen5_gt_irq_reset(dev_priv);

        ibx_irq_reset(dev_priv);
}

static void valleyview_irq_preinstall(struct drm_device *dev)
{
        struct drm_i915_private *dev_priv = to_i915(dev);

        I915_WRITE(VLV_MASTER_IER, 0);
        POSTING_READ(VLV_MASTER_IER);

        gen5_gt_irq_reset(dev_priv);

        spin_lock_irq(&dev_priv->irq_lock);
        if (dev_priv->display_irqs_enabled)
                vlv_display_irq_reset(dev_priv);
        spin_unlock_irq(&dev_priv->irq_lock);
}

static void gen8_gt_irq_reset(struct drm_i915_private *dev_priv)
{
        GEN8_IRQ_RESET_NDX(GT, 0);
        GEN8_IRQ_RESET_NDX(GT, 1);
        GEN8_IRQ_RESET_NDX(GT, 2);
        GEN8_IRQ_RESET_NDX(GT, 3);
}

static void gen8_irq_reset(struct drm_device *dev)
{
        struct drm_i915_private *dev_priv = to_i915(dev);
        int pipe;

        I915_WRITE(GEN8_MASTER_IRQ, 0);
        POSTING_READ(GEN8_MASTER_IRQ);

        gen8_gt_irq_reset(dev_priv);

        for_each_pipe(dev_priv, pipe)
                if (intel_display_power_is_enabled(dev_priv,