/* i915_drv.c -- i830,i845,i855,i865,i915 driver -*- 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.
 *
 */

#include <linux/device.h>
#include "drmP.h"
#include "drm.h"
#include "i915_drm.h"
#include "i915_drv.h"
#include "intel_drv.h"

#include <linux/console.h>
#include <linux/module.h>
#include "drm_crtc_helper.h"

static int i915_modeset __read_mostly = -1;
module_param_named(modeset, i915_modeset, int, 0400);
MODULE_PARM_DESC(modeset,
                "Use kernel modesetting [KMS] (0=DRM_I915_KMS from .config, "
                "1=on, -1=force vga console preference [default])");

unsigned int i915_fbpercrtc __always_unused = 0;
module_param_named(fbpercrtc, i915_fbpercrtc, int, 0400);

int i915_panel_ignore_lid __read_mostly = 0;
module_param_named(panel_ignore_lid, i915_panel_ignore_lid, int, 0600);
MODULE_PARM_DESC(panel_ignore_lid,
                "Override lid status (0=autodetect [default], 1=lid open, "
                "-1=lid closed)");

unsigned int i915_powersave __read_mostly = 1;
module_param_named(powersave, i915_powersave, int, 0600);
MODULE_PARM_DESC(powersave,
                "Enable powersavings, fbc, downclocking, etc. (default: true)");

int i915_semaphores __read_mostly = -1;
module_param_named(semaphores, i915_semaphores, int, 0600);
MODULE_PARM_DESC(semaphores,
                "Use semaphores for inter-ring sync (default: -1 (use per-chip defaults))");

int i915_enable_rc6 __read_mostly = -1;
module_param_named(i915_enable_rc6, i915_enable_rc6, int, 0400);
MODULE_PARM_DESC(i915_enable_rc6,
                "Enable power-saving render C-state 6. "
                "Different stages can be selected via bitmask values "
                "(0 = disable; 1 = enable rc6; 2 = enable deep rc6; 4 = enable deepest rc6). "
                "For example, 3 would enable rc6 and deep rc6, and 7 would enable everything. "
                "default: -1 (use per-chip default)");

int i915_enable_fbc __read_mostly = -1;
module_param_named(i915_enable_fbc, i915_enable_fbc, int, 0600);
MODULE_PARM_DESC(i915_enable_fbc,
                "Enable frame buffer compression for power savings "
                "(default: -1 (use per-chip default))");

unsigned int i915_lvds_downclock __read_mostly = 0;
module_param_named(lvds_downclock, i915_lvds_downclock, int, 0400);
MODULE_PARM_DESC(lvds_downclock,
                "Use panel (LVDS/eDP) downclocking for power savings "
                "(default: false)");

int i915_panel_use_ssc __read_mostly = -1;
module_param_named(lvds_use_ssc, i915_panel_use_ssc, int, 0600);
MODULE_PARM_DESC(lvds_use_ssc,
                "Use Spread Spectrum Clock with panels [LVDS/eDP] "
                "(default: auto from VBT)");

int i915_vbt_sdvo_panel_type __read_mostly = -1;
module_param_named(vbt_sdvo_panel_type, i915_vbt_sdvo_panel_type, int, 0600);
MODULE_PARM_DESC(vbt_sdvo_panel_type,
                "Override selection of SDVO panel mode in the VBT "
                "(default: auto)");

static bool i915_try_reset __read_mostly = true;
module_param_named(reset, i915_try_reset, bool, 0600);
MODULE_PARM_DESC(reset, "Attempt GPU resets (default: true)");

bool i915_enable_hangcheck __read_mostly = true;
module_param_named(enable_hangcheck, i915_enable_hangcheck, bool, 0644);
MODULE_PARM_DESC(enable_hangcheck,
                "Periodically check GPU activity for detecting hangs. "
                "WARNING: Disabling this can cause system wide hangs. "
                "(default: true)");

int i915_enable_ppgtt __read_mostly = -1;
module_param_named(i915_enable_ppgtt, i915_enable_ppgtt, int, 0600);
MODULE_PARM_DESC(i915_enable_ppgtt,
                "Enable PPGTT (default: true)");

static struct drm_driver driver;
extern int intel_agp_enabled;

#define INTEL_VGA_DEVICE(id, info) {            \
        .class = PCI_BASE_CLASS_DISPLAY << 16,  \
        .class_mask = 0xff0000,                 \
        .vendor = 0x8086,                       \
        .device = id,                           \
        .subvendor = PCI_ANY_ID,                \
        .subdevice = PCI_ANY_ID,                \
        .driver_data = (unsigned long) info }

static const struct intel_device_info intel_i830_info = {
        .gen = 2, .is_mobile = 1, .cursor_needs_physical = 1,
        .has_overlay = 1, .overlay_needs_physical = 1,
};

static const struct intel_device_info intel_845g_info = {
        .gen = 2,
        .has_overlay = 1, .overlay_needs_physical = 1,
};

static const struct intel_device_info intel_i85x_info = {
        .gen = 2, .is_i85x = 1, .is_mobile = 1,
        .cursor_needs_physical = 1,
        .has_overlay = 1, .overlay_needs_physical = 1,
};

static const struct intel_device_info intel_i865g_info = {
        .gen = 2,
        .has_overlay = 1, .overlay_needs_physical = 1,
};

static const struct intel_device_info intel_i915g_info = {
        .gen = 3, .is_i915g = 1, .cursor_needs_physical = 1,
        .has_overlay = 1, .overlay_needs_physical = 1,
};
static const struct intel_device_info intel_i915gm_info = {
        .gen = 3, .is_mobile = 1,
        .cursor_needs_physical = 1,
        .has_overlay = 1, .overlay_needs_physical = 1,
        .supports_tv = 1,
};
static const struct intel_device_info intel_i945g_info = {
        .gen = 3, .has_hotplug = 1, .cursor_needs_physical = 1,
        .has_overlay = 1, .overlay_needs_physical = 1,
};
static const struct intel_device_info intel_i945gm_info = {
        .gen = 3, .is_i945gm = 1, .is_mobile = 1,
        .has_hotplug = 1, .cursor_needs_physical = 1,
        .has_overlay = 1, .overlay_needs_physical = 1,
        .supports_tv = 1,
};

static const struct intel_device_info intel_i965g_info = {
        .gen = 4, .is_broadwater = 1,
        .has_hotplug = 1,
        .has_overlay = 1,
};

static const struct intel_device_info intel_i965gm_info = {
        .gen = 4, .is_crestline = 1,
        .is_mobile = 1, .has_fbc = 1, .has_hotplug = 1,
        .has_overlay = 1,
        .supports_tv = 1,
};

static const struct intel_device_info intel_g33_info = {
        .gen = 3, .is_g33 = 1,
        .need_gfx_hws = 1, .has_hotplug = 1,
        .has_overlay = 1,
};

static const struct intel_device_info intel_g45_info = {
        .gen = 4, .is_g4x = 1, .need_gfx_hws = 1,
        .has_pipe_cxsr = 1, .has_hotplug = 1,
        .has_bsd_ring = 1,
};

static const struct intel_device_info intel_gm45_info = {
        .gen = 4, .is_g4x = 1,
        .is_mobile = 1, .need_gfx_hws = 1, .has_fbc = 1,
        .has_pipe_cxsr = 1, .has_hotplug = 1,
        .supports_tv = 1,
        .has_bsd_ring = 1,
};

static const struct intel_device_info intel_pineview_info = {
        .gen = 3, .is_g33 = 1, .is_pineview = 1, .is_mobile = 1,
        .need_gfx_hws = 1, .has_hotplug = 1,
        .has_overlay = 1,
};

static const struct intel_device_info intel_ironlake_d_info = {
        .gen = 5,
        .need_gfx_hws = 1, .has_hotplug = 1,
        .has_bsd_ring = 1,
};

static const struct intel_device_info intel_ironlake_m_info = {
        .gen = 5, .is_mobile = 1,
        .need_gfx_hws = 1, .has_hotplug = 1,
        .has_fbc = 1,
        .has_bsd_ring = 1,
};

static const struct intel_device_info intel_sandybridge_d_info = {
        .gen = 6,
        .need_gfx_hws = 1, .has_hotplug = 1,
        .has_bsd_ring = 1,
        .has_blt_ring = 1,
        .has_llc = 1,
};

static const struct intel_device_info intel_sandybridge_m_info = {
        .gen = 6, .is_mobile = 1,
        .need_gfx_hws = 1, .has_hotplug = 1,
        .has_fbc = 1,
        .has_bsd_ring = 1,
        .has_blt_ring = 1,
        .has_llc = 1,
};

static const struct intel_device_info intel_ivybridge_d_info = {
        .is_ivybridge = 1, .gen = 7,
        .need_gfx_hws = 1, .has_hotplug = 1,
        .has_bsd_ring = 1,
        .has_blt_ring = 1,
        .has_llc = 1,
};

static const struct intel_device_info intel_ivybridge_m_info = {
        .is_ivybridge = 1, .gen = 7, .is_mobile = 1,
        .need_gfx_hws = 1, .has_hotplug = 1,
        .has_fbc = 0,   /* FBC is not enabled on Ivybridge mobile yet */
        .has_bsd_ring = 1,
        .has_blt_ring = 1,
        .has_llc = 1,
};

static const struct pci_device_id pciidlist[] = {               /* aka */
        INTEL_VGA_DEVICE(0x3577, &intel_i830_info),             /* I830_M */
        INTEL_VGA_DEVICE(0x2562, &intel_845g_info),             /* 845_G */
        INTEL_VGA_DEVICE(0x3582, &intel_i85x_info),             /* I855_GM */
        INTEL_VGA_DEVICE(0x358e, &intel_i85x_info),
        INTEL_VGA_DEVICE(0x2572, &intel_i865g_info),            /* I865_G */
        INTEL_VGA_DEVICE(0x2582, &intel_i915g_info),            /* I915_G */
        INTEL_VGA_DEVICE(0x258a, &intel_i915g_info),            /* E7221_G */
        INTEL_VGA_DEVICE(0x2592, &intel_i915gm_info),           /* I915_GM */
        INTEL_VGA_DEVICE(0x2772, &intel_i945g_info),            /* I945_G */
        INTEL_VGA_DEVICE(0x27a2, &intel_i945gm_info),           /* I945_GM */
        INTEL_VGA_DEVICE(0x27ae, &intel_i945gm_info),           /* I945_GME */
        INTEL_VGA_DEVICE(0x2972, &intel_i965g_info),            /* I946_GZ */
        INTEL_VGA_DEVICE(0x2982, &intel_i965g_info),            /* G35_G */
        INTEL_VGA_DEVICE(0x2992, &intel_i965g_info),            /* I965_Q */
        INTEL_VGA_DEVICE(0x29a2, &intel_i965g_info),            /* I965_G */
        INTEL_VGA_DEVICE(0x29b2, &intel_g33_info),              /* Q35_G */
        INTEL_VGA_DEVICE(0x29c2, &intel_g33_info),              /* G33_G */
        INTEL_VGA_DEVICE(0x29d2, &intel_g33_info),              /* Q33_G */
        INTEL_VGA_DEVICE(0x2a02, &intel_i965gm_info),           /* I965_GM */
        INTEL_VGA_DEVICE(0x2a12, &intel_i965gm_info),           /* I965_GME */
        INTEL_VGA_DEVICE(0x2a42, &intel_gm45_info),             /* GM45_G */
        INTEL_VGA_DEVICE(0x2e02, &intel_g45_info),              /* IGD_E_G */
        INTEL_VGA_DEVICE(0x2e12, &intel_g45_info),              /* Q45_G */
        INTEL_VGA_DEVICE(0x2e22, &intel_g45_info),              /* G45_G */
        INTEL_VGA_DEVICE(0x2e32, &intel_g45_info),              /* G41_G */
        INTEL_VGA_DEVICE(0x2e42, &intel_g45_info),              /* B43_G */
        INTEL_VGA_DEVICE(0x2e92, &intel_g45_info),              /* B43_G.1 */
        INTEL_VGA_DEVICE(0xa001, &intel_pineview_info),
        INTEL_VGA_DEVICE(0xa011, &intel_pineview_info),
        INTEL_VGA_DEVICE(0x0042, &intel_ironlake_d_info),
        INTEL_VGA_DEVICE(0x0046, &intel_ironlake_m_info),
        INTEL_VGA_DEVICE(0x0102, &intel_sandybridge_d_info),
        INTEL_VGA_DEVICE(0x0112, &intel_sandybridge_d_info),
        INTEL_VGA_DEVICE(0x0122, &intel_sandybridge_d_info),
        INTEL_VGA_DEVICE(0x0106, &intel_sandybridge_m_info),
        INTEL_VGA_DEVICE(0x0116, &intel_sandybridge_m_info),
        INTEL_VGA_DEVICE(0x0126, &intel_sandybridge_m_info),
        INTEL_VGA_DEVICE(0x010A, &intel_sandybridge_d_info),
        INTEL_VGA_DEVICE(0x0156, &intel_ivybridge_m_info), /* GT1 mobile */
        INTEL_VGA_DEVICE(0x0166, &intel_ivybridge_m_info), /* GT2 mobile */
        INTEL_VGA_DEVICE(0x0152, &intel_ivybridge_d_info), /* GT1 desktop */
        INTEL_VGA_DEVICE(0x0162, &intel_ivybridge_d_info), /* GT2 desktop */
        INTEL_VGA_DEVICE(0x015a, &intel_ivybridge_d_info), /* GT1 server */
        INTEL_VGA_DEVICE(0x016a, &intel_ivybridge_d_info), /* GT2 server */
        {0, 0, 0}
};

#if defined(CONFIG_DRM_I915_KMS)
MODULE_DEVICE_TABLE(pci, pciidlist);
#endif

#define INTEL_PCH_DEVICE_ID_MASK        0xff00
#define INTEL_PCH_IBX_DEVICE_ID_TYPE    0x3b00
#define INTEL_PCH_CPT_DEVICE_ID_TYPE    0x1c00
#define INTEL_PCH_PPT_DEVICE_ID_TYPE    0x1e00

void intel_detect_pch(struct drm_device *dev)
{
        struct drm_i915_private *dev_priv = dev->dev_private;
        struct pci_dev *pch;

        /*
         * The reason to probe ISA bridge instead of Dev31:Fun0 is to
         * make graphics device passthrough work easy for VMM, that only
         * need to expose ISA bridge to let driver know the real hardware
         * underneath. This is a requirement from virtualization team.
         */
        pch = pci_get_class(PCI_CLASS_BRIDGE_ISA << 8, NULL);
        if (pch) {
                if (pch->vendor == PCI_VENDOR_ID_INTEL) {
                        int id;
                        id = pch->device & INTEL_PCH_DEVICE_ID_MASK;

                        if (id == INTEL_PCH_IBX_DEVICE_ID_TYPE) {
                                dev_priv->pch_type = PCH_IBX;
                                DRM_DEBUG_KMS("Found Ibex Peak PCH\n");
                        } else if (id == INTEL_PCH_CPT_DEVICE_ID_TYPE) {
                                dev_priv->pch_type = PCH_CPT;
                                DRM_DEBUG_KMS("Found CougarPoint PCH\n");
                        } else if (id == INTEL_PCH_PPT_DEVICE_ID_TYPE) {
                                /* PantherPoint is CPT compatible */
                                dev_priv->pch_type = PCH_CPT;
                                DRM_DEBUG_KMS("Found PatherPoint PCH\n");
                        }
                }
                pci_dev_put(pch);
        }
}

void __gen6_gt_force_wake_get(struct drm_i915_private *dev_priv)
{
        int count;

        count = 0;
        while (count++ < 50 && (I915_READ_NOTRACE(FORCEWAKE_ACK) & 1))
                udelay(10);

        I915_WRITE_NOTRACE(FORCEWAKE, 1);
        POSTING_READ(FORCEWAKE);

        count = 0;
        while (count++ < 50 && (I915_READ_NOTRACE(FORCEWAKE_ACK) & 1) == 0)
                udelay(10);
}

void __gen6_gt_force_wake_mt_get(struct drm_i915_private *dev_priv)
{
        int count;

        count = 0;
        while (count++ < 50 && (I915_READ_NOTRACE(FORCEWAKE_MT_ACK) & 1))
                udelay(10);

        I915_WRITE_NOTRACE(FORCEWAKE_MT, (1<<16) | 1);
        POSTING_READ(FORCEWAKE_MT);

        count = 0;
        while (count++ < 50 && (I915_READ_NOTRACE(FORCEWAKE_MT_ACK) & 1) == 0)
                udelay(10);
}

/*
 * Generally this is called implicitly by the register read function. However,
 * if some sequence requires the GT to not power down then this function should
 * be called at the beginning of the sequence followed by a call to
 * gen6_gt_force_wake_put() at the end of the sequence.
 */
void gen6_gt_force_wake_get(struct drm_i915_private *dev_priv)
{
        unsigned long irqflags;

        spin_lock_irqsave(&dev_priv->gt_lock, irqflags);
        if (dev_priv->forcewake_count++ == 0)
                dev_priv->display.force_wake_get(dev_priv);
        spin_unlock_irqrestore(&dev_priv->gt_lock, irqflags);
}

static void gen6_gt_check_fifodbg(struct drm_i915_private *dev_priv)
{
        u32 gtfifodbg;
        gtfifodbg = I915_READ_NOTRACE(GTFIFODBG);
        if (WARN(gtfifodbg & GT_FIFO_CPU_ERROR_MASK,
             "MMIO read or write has been dropped %x\n", gtfifodbg))
                I915_WRITE_NOTRACE(GTFIFODBG, GT_FIFO_CPU_ERROR_MASK);
}

void __gen6_gt_force_wake_put(struct drm_i915_private *dev_priv)
{
        I915_WRITE_NOTRACE(FORCEWAKE, 0);
        /* The below doubles as a POSTING_READ */
        gen6_gt_check_fifodbg(dev_priv);
}

void __gen6_gt_force_wake_mt_put(struct drm_i915_private *dev_priv)
{
        I915_WRITE_NOTRACE(FORCEWAKE_MT, (1<<16) | 0);
        /* The below doubles as a POSTING_READ */
        gen6_gt_check_fifodbg(dev_priv);
}

/*
 * see gen6_gt_force_wake_get()
 */
void gen6_gt_force_wake_put(struct drm_i915_private *dev_priv)
{
        unsigned long irqflags;

        spin_lock_irqsave(&dev_priv->gt_lock, irqflags);
        if (--dev_priv->forcewake_count == 0)
                dev_priv->display.force_wake_put(dev_priv);
        spin_unlock_irqrestore(&dev_priv->gt_lock, irqflags);
}

int __gen6_gt_wait_for_fifo(struct drm_i915_private *dev_priv)
{
        int ret = 0;

        if (dev_priv->gt_fifo_count < GT_FIFO_NUM_RESERVED_ENTRIES) {
                int loop = 500;
                u32 fifo = I915_READ_NOTRACE(GT_FIFO_FREE_ENTRIES);
                while (fifo <= GT_FIFO_NUM_RESERVED_ENTRIES && loop--) {
                        udelay(10);
                        fifo = I915_READ_NOTRACE(GT_FIFO_FREE_ENTRIES);
                }
                if (WARN_ON(loop < 0 && fifo <= GT_FIFO_NUM_RESERVED_ENTRIES))
                        ++ret;
                dev_priv->gt_fifo_count = fifo;
        }
        dev_priv->gt_fifo_count--;

        return ret;
}

static int i915_drm_freeze(struct drm_device *dev)
{
        struct drm_i915_private *dev_priv = dev->dev_private;

        drm_kms_helper_poll_disable(dev);

        pci_save_state(dev->pdev);

        /* If KMS is active, we do the leavevt stuff here */
        if (drm_core_check_feature(dev, DRIVER_MODESET)) {
                int error = i915_gem_idle(dev);
                if (error) {
                        dev_err(&dev->pdev->dev,
                                "GEM idle failed, resume might fail\n");
                        return error;
                }
                drm_irq_uninstall(dev);
        }

        i915_save_state(dev);

        intel_opregion_fini(dev);

        /* Modeset on resume, not lid events */
        dev_priv->modeset_on_lid = 0;

        console_lock();
        intel_fbdev_set_suspend(dev, 1);
        console_unlock();

        return 0;
}

int i915_suspend(struct drm_device *dev, pm_message_t state)
{
        int error;

        if (!dev || !dev->dev_private) {
                DRM_ERROR("dev: %p\n", dev);
                DRM_ERROR("DRM not initialized, aborting suspend.\n");
                return -ENODEV;
        }

        if (state.event == PM_EVENT_PRETHAW)
                return 0;


        if (dev->switch_power_state == DRM_SWITCH_POWER_OFF)
                return 0;

        error = i915_drm_freeze(dev);
        if (error)
                return error;

        if (state.event == PM_EVENT_SUSPEND) {
                /* Shut down the device */
                pci_disable_device(dev->pdev);
                pci_set_power_state(dev->pdev, PCI_D3hot);
        }

        return 0;
}

static int i915_drm_thaw(struct drm_device *dev)
{
        struct drm_i915_private *dev_priv = dev->dev_private;
        int error = 0;

        if (drm_core_check_feature(dev, DRIVER_MODESET)) {
                mutex_lock(&dev->struct_mutex);
                i915_gem_restore_gtt_mappings(dev);
                mutex_unlock(&dev->struct_mutex);
        }

        i915_restore_state(dev);
        intel_opregion_setup(dev);

        /* KMS EnterVT equivalent */
        if (drm_core_check_feature(dev, DRIVER_MODESET)) {
                mutex_lock(&dev->struct_mutex);
                dev_priv->mm.suspended = 0;

                error = i915_gem_init_hw(dev);
                mutex_unlock(&dev->struct_mutex);

                if (HAS_PCH_SPLIT(dev))
                        ironlake_init_pch_refclk(dev);

                drm_mode_config_reset(dev);
                drm_irq_install(dev);

                /* Resume the modeset for every activated CRTC */
                mutex_lock(&dev->mode_config.mutex);
                drm_helper_resume_force_mode(dev);
                mutex_unlock(&dev->mode_config.mutex);

                if (IS_IRONLAKE_M(dev))
                        ironlake_enable_rc6(dev);
        }

        intel_opregion_init(dev);

        dev_priv->modeset_on_lid = 0;

        console_lock();
        intel_fbdev_set_suspend(dev, 0);
        console_unlock();
        return error;
}

int i915_resume(struct drm_device *dev)
{
        int ret;

        if (dev->switch_power_state == DRM_SWITCH_POWER_OFF)
                return 0;

        if (pci_enable_device(dev->pdev))
                return -EIO;

        pci_set_master(dev->pdev);

        ret = i915_drm_thaw(dev);
        if (ret)
                return ret;

        drm_kms_helper_poll_enable(dev);
        return 0;
}

static int i8xx_do_reset(struct drm_device *dev, u8 flags)
{
        struct drm_i915_private *dev_priv = dev->dev_private;

        if (IS_I85X(dev))
                return -ENODEV;

        I915_WRITE(D_STATE, I915_READ(D_STATE) | DSTATE_GFX_RESET_I830);
        POSTING_READ(D_STATE);

        if (IS_I830(dev) || IS_845G(dev)) {
                I915_WRITE(DEBUG_RESET_I830,
                           DEBUG_RESET_DISPLAY |
                           DEBUG_RESET_RENDER |
                           DEBUG_RESET_FULL);
                POSTING_READ(DEBUG_RESET_I830);
                msleep(1);

                I915_WRITE(DEBUG_RESET_I830, 0);
                POSTING_READ(DEBUG_RESET_I830);
        }

        msleep(1);

        I915_WRITE(D_STATE, I915_READ(D_STATE) & ~DSTATE_GFX_RESET_I830);
        POSTING_READ(D_STATE);

        return 0;
}

static int i965_reset_complete(struct drm_device *dev)
{
        u8 gdrst;
        pci_read_config_byte(dev->pdev, I965_GDRST, &gdrst);
        return gdrst & 0x1;
}

static int i965_do_reset(struct drm_device *dev, u8 flags)
{
        u8 gdrst;

        /*
         * Set the domains we want to reset (GRDOM/bits 2 and 3) as
         * well as the reset bit (GR/bit 0).  Setting the GR bit
         * triggers the reset; when done, the hardware will clear it.
         */
        pci_read_config_byte(dev->pdev, I965_GDRST, &gdrst);
        pci_write_config_byte(dev->pdev, I965_GDRST, gdrst | flags | 0x1);

        return wait_for(i965_reset_complete(dev), 500);
}

static int ironlake_do_reset(struct drm_device *dev, u8 flags)
{
        struct drm_i915_private *dev_priv = dev->dev_private;
        u32 gdrst = I915_READ(MCHBAR_MIRROR_BASE + ILK_GDSR);
        I915_WRITE(MCHBAR_MIRROR_BASE + ILK_GDSR, gdrst | flags | 0x1);
        return wait_for(I915_READ(MCHBAR_MIRROR_BASE + ILK_GDSR) & 0x1, 500);
}

static int gen6_do_reset(struct drm_device *dev, u8 flags)
{
        struct drm_i915_private *dev_priv = dev->dev_private;
        int     ret;
        unsigned long irqflags;

        /* Hold gt_lock across reset to prevent any register access
         * with forcewake not set correctly
         */
        spin_lock_irqsave(&dev_priv->gt_lock, irqflags);

        /* Reset the chip */

        /* GEN6_GDRST is not in the gt power well, no need to check
         * for fifo space for the write or forcewake the chip for
         * the read
         */
        I915_WRITE_NOTRACE(GEN6_GDRST, GEN6_GRDOM_FULL);

        /* Spin waiting for the device to ack the reset request */
        ret = wait_for((I915_READ_NOTRACE(GEN6_GDRST) & GEN6_GRDOM_FULL) == 0, 500);

        /* If reset with a user forcewake, try to restore, otherwise turn it off */
        if (dev_priv->forcewake_count)
                dev_priv->display.force_wake_get(dev_priv);
        else
                dev_priv->display.force_wake_put(dev_priv);

        /* Restore fifo count */
        dev_priv->gt_fifo_count = I915_READ_NOTRACE(GT_FIFO_FREE_ENTRIES);

        spin_unlock_irqrestore(&dev_priv->gt_lock, irqflags);
        return ret;
}

/**
 * i915_reset - reset chip after a hang
 * @dev: drm device to reset
 * @flags: reset domains
 *
 * Reset the chip.  Useful if a hang is detected. Returns zero on successful
 * reset or otherwise an error code.
 *
 * Procedure is fairly simple:
 *   - reset the chip using the reset reg
 *   - re-init context state
 *   - re-init hardware status page
 *   - re-init ring buffer
 *   - re-init interrupt state
 *   - re-init display
 */
int i915_reset(struct drm_device *dev, u8 flags)
{
        drm_i915_private_t *dev_priv = dev->dev_private;
        /*
         * We really should only reset the display subsystem if we actually
         * need to
         */
        bool need_display = true;
        int ret;

        if (!i915_try_reset)
                return 0;

        if (!mutex_trylock(&dev->struct_mutex))
                return -EBUSY;

        i915_gem_reset(dev);

        ret = -ENODEV;
        if (get_seconds() - dev_priv->last_gpu_reset < 5) {
                DRM_ERROR("GPU hanging too fast, declaring wedged!\n");
        } else switch (INTEL_INFO(dev)->gen) {
        case 7:
        case 6:
                ret = gen6_do_reset(dev, flags);
                break;
        case 5:
                ret = ironlake_do_reset(dev, flags);
                break;
        case 4:
                ret = i965_do_reset(dev, flags);
                break;
        case 2:
                ret = i8xx_do_reset(dev, flags);
                break;
        }
        dev_priv->last_gpu_reset = get_seconds();
        if (ret) {
                DRM_ERROR("Failed to reset chip.\n");
                mutex_unlock(&dev->struct_mutex);
                return ret;
        }

        /* Ok, now get things going again... */

        /*
         * Everything depends on having the GTT running, so we need to start
         * there.  Fortunately we don't need to do this unless we reset the
         * chip at a PCI level.
         *
         * Next we need to restore the context, but we don't use those
         * yet either...
         *
         * Ring buffer needs to be re-initialized in the KMS case, or if X
         * was running at the time of the reset (i.e. we weren't VT
         * switched away).
         */
        if (drm_core_check_feature(dev, DRIVER_MODESET) ||
                        !dev_priv->mm.suspended) {
                dev_priv->mm.suspended = 0;

                i915_gem_init_swizzling(dev);

                dev_priv->ring[RCS].init(&dev_priv->ring[RCS]);
                if (HAS_BSD(dev))
                    dev_priv->ring[VCS].init(&dev_priv->ring[VCS]);
                if (HAS_BLT(dev))
                    dev_priv->ring[BCS].init(&dev_priv->ring[BCS]);

                i915_gem_init_ppgtt(dev);

                mutex_unlock(&dev->struct_mutex);
                drm_irq_uninstall(dev);
                drm_mode_config_reset(dev);
                drm_irq_install(dev);
                mutex_lock(&dev->struct_mutex);
        }

        mutex_unlock(&dev->struct_mutex);

        /*
         * Perform a full modeset as on later generations, e.g. Ironlake, we may
         * need to retrain the display link and cannot just restore the register
         * values.
         */
        if (need_display) {
                mutex_lock(&dev->mode_config.mutex);
                drm_helper_resume_force_mode(dev);
                mutex_unlock(&dev->mode_config.mutex);
        }

        return 0;
}


static int __devinit
i915_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
{
        /* Only bind to function 0 of the device. Early generations
         * used function 1 as a placeholder for multi-head. This causes
         * us confusion instead, especially on the systems where both
         * functions have the same PCI-ID!
         */
        if (PCI_FUNC(pdev->devfn))
                return -ENODEV;

        return drm_get_pci_dev(pdev, ent, &driver);
}

static void
i915_pci_remove(struct pci_dev *pdev)
{
        struct drm_device *dev = pci_get_drvdata(pdev);

        drm_put_dev(dev);
}

static int i915_pm_suspend(struct device *dev)
{
        struct pci_dev *pdev = to_pci_dev(dev);
        struct drm_device *drm_dev = pci_get_drvdata(pdev);
        int error;

        if (!drm_dev || !drm_dev->dev_private) {
                dev_err(dev, "DRM not initialized, aborting suspend.\n");
                return -ENODEV;
        }

        if (drm_dev->switch_power_state == DRM_SWITCH_POWER_OFF)
                return 0;

        error = i915_drm_freeze(drm_dev);
        if (error)
                return error;

        pci_disable_device(pdev);
        pci_set_power_state(pdev, PCI_D3hot);

        return 0;
}

static int i915_pm_resume(struct device *dev)
{
        struct pci_dev *pdev = to_pci_dev(dev);
        struct drm_device *drm_dev = pci_get_drvdata(pdev);

        return i915_resume(drm_dev);
}

static int i915_pm_freeze(struct device *dev)
{
        struct pci_dev *pdev = to_pci_dev(dev);
        struct drm_device *drm_dev = pci_get_drvdata(pdev);

        if (!drm_dev || !drm_dev->dev_private) {
                dev_err(dev, "DRM not initialized, aborting suspend.\n");
                return -ENODEV;
        }

        return i915_drm_freeze(drm_dev);
}

static int i915_pm_thaw(struct device *dev)
{
        struct pci_dev *pdev = to_pci_dev(dev);
        struct drm_device *drm_dev = pci_get_drvdata(pdev);

        return i915_drm_thaw(drm_dev);
}

static int i915_pm_poweroff(struct device *dev)
{
        struct pci_dev *pdev = to_pci_dev(dev);
        struct drm_device *drm_dev = pci_get_drvdata(pdev);

        return i915_drm_freeze(drm_dev);
}

static const struct dev_pm_ops i915_pm_ops = {
        .suspend = i915_pm_suspend,
        .resume = i915_pm_resume,
        .freeze = i915_pm_freeze,
        .thaw = i915_pm_thaw,
        .poweroff = i915_pm_poweroff,
        .restore = i915_pm_resume,
};

static struct vm_operations_struct i915_gem_vm_ops = {
        .fault = i915_gem_fault,
        .open = drm_gem_vm_open,
        .close = drm_gem_vm_close,
};

static const struct file_operations i915_driver_fops = {
        .owner = THIS_MODULE,
        .open = drm_open,
        .release = drm_release,
        .unlocked_ioctl = drm_ioctl,
        .mmap = drm_gem_mmap,
        .poll = drm_poll,
        .fasync = drm_fasync,
        .read = drm_read,
#ifdef CONFIG_COMPAT
        .compat_ioctl = i915_compat_ioctl,
#endif
        .llseek = noop_llseek,
};

static struct drm_driver driver = {
        /* Don't use MTRRs here; the Xserver or userspace app should
         * deal with them for Intel hardware.
         */
        .driver_features =
            DRIVER_USE_AGP | DRIVER_REQUIRE_AGP | /* DRIVER_USE_MTRR |*/
            DRIVER_HAVE_IRQ | DRIVER_IRQ_SHARED | DRIVER_GEM,
        .load = i915_driver_load,
        .unload = i915_driver_unload,
        .open = i915_driver_open,
        .lastclose = i915_driver_lastclose,
        .preclose = i915_driver_preclose,
        .postclose = i915_driver_postclose,

        /* Used in place of i915_pm_ops for non-DRIVER_MODESET */
        .suspend = i915_suspend,
        .resume = i915_resume,

        .device_is_agp = i915_driver_device_is_agp,
        .reclaim_buffers = drm_core_reclaim_buffers,
        .master_create = i915_master_create,
        .master_destroy = i915_master_destroy,
#if defined(CONFIG_DEBUG_FS)
        .debugfs_init = i915_debugfs_init,
        .debugfs_cleanup = i915_debugfs_cleanup,
#endif
        .gem_init_object = i915_gem_init_object,
        .gem_free_object = i915_gem_free_object,
        .gem_vm_ops = &i915_gem_vm_ops,
        .dumb_create = i915_gem_dumb_create,
        .dumb_map_offset = i915_gem_mmap_gtt,
        .dumb_destroy = i915_gem_dumb_destroy,
        .ioctls = i915_ioctls,
        .fops = &i915_driver_fops,
        .name = DRIVER_NAME,
        .desc = DRIVER_DESC,
        .date = DRIVER_DATE,
        .major = DRIVER_MAJOR,
        .minor = DRIVER_MINOR,
        .patchlevel = DRIVER_PATCHLEVEL,
};

static struct pci_driver i915_pci_driver = {
        .name = DRIVER_NAME,
        .id_table = pciidlist,
        .probe = i915_pci_probe,
        .remove = i915_pci_remove,
        .driver.pm = &i915_pm_ops,
};

static int __init i915_init(void)
{
        if (!intel_agp_enabled) {
                DRM_ERROR("drm/i915 can't work without intel_agp module!\n");
                return -ENODEV;
        }

        driver.num_ioctls = i915_max_ioctl;

        /*
         * If CONFIG_DRM_I915_KMS is set, default to KMS unless
         * explicitly disabled with the module pararmeter.
         *
         * Otherwise, just follow the parameter (defaulting to off).
         *
         * Allow optional vga_text_mode_force boot option to override
         * the default behavior.
         */
#if defined(CONFIG_DRM_I915_KMS)
        if (i915_modeset != 0)
                driver.driver_features |= DRIVER_MODESET;
#endif
        if (i915_modeset == 1)
                driver.driver_features |= DRIVER_MODESET;

#ifdef CONFIG_VGA_CONSOLE
        if (vgacon_text_force() && i915_modeset == -1)
                driver.driver_features &= ~DRIVER_MODESET;
#endif

        if (!(driver.driver_features & DRIVER_MODESET))
                driver.get_vblank_timestamp = NULL;

        return drm_pci_init(&driver, &i915_pci_driver);
}

static void __exit i915_exit(void)
{
        drm_pci_exit(&driver, &i915_pci_driver);
}

module_init(i915_init);
module_exit(i915_exit);

MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL and additional rights");

#define __i915_read(x, y) \
u##x i915_read##x(struct drm_i915_private *dev_priv, u32 reg) { \
        u##x val = 0; \
        if (NEEDS_FORCE_WAKE((dev_priv), (reg))) { \
                unsigned long irqflags; \

                spin_lock_irqsave(&dev_priv->gt_lock, irqflags); \
                if (dev_priv->forcewake_count == 0) \
                        dev_priv->display.force_wake_get(dev_priv); \
                val = read##y(dev_priv->regs + reg); \
                if (dev_priv->forcewake_count == 0) \
                        dev_priv->display.force_wake_put(dev_priv); \
                spin_unlock_irqrestore(&dev_priv->gt_lock, irqflags); \
        } else { \
                val = read##y(dev_priv->regs + reg); \
        } \
        trace_i915_reg_rw(false, reg, val, sizeof(val)); \
        return val; \
}

__i915_read(8, b)
__i915_read(16, w)
__i915_read(32, l)
__i915_read(64, q)
#undef __i915_read

#define __i915_write(x, y) \
void i915_write##x(struct drm_i915_private *dev_priv, u32 reg, u##x val) { \
        u32 __fifo_ret = 0; \
        trace_i915_reg_rw(true, reg, val, sizeof(val)); \
        if (NEEDS_FORCE_WAKE((dev_priv), (reg))) { \
                __fifo_ret = __gen6_gt_wait_for_fifo(dev_priv); \
        } \
        write##y(val, dev_priv->regs + reg); \
        if (unlikely(__fifo_ret)) { \
                gen6_gt_check_fifodbg(dev_priv); \
        } \
}
__i915_write(8, b)
__i915_write(16, w)
__i915_write(32, l)
__i915_write(64, q)
#undef __i915_write