/*
 * Copyright (C) 2015 Etnaviv Project
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published by
 * the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <linux/component.h>
#include <linux/dma-fence.h>
#include <linux/moduleparam.h>
#include <linux/of_device.h>

#include "etnaviv_cmdbuf.h"
#include "etnaviv_dump.h"
#include "etnaviv_gpu.h"
#include "etnaviv_gem.h"
#include "etnaviv_mmu.h"
#include "common.xml.h"
#include "state.xml.h"
#include "state_hi.xml.h"
#include "cmdstream.xml.h"

static const struct platform_device_id gpu_ids[] = {
        { .name = "etnaviv-gpu,2d" },
        { },
};

static bool etnaviv_dump_core = true;
module_param_named(dump_core, etnaviv_dump_core, bool, 0600);

/*
 * Driver functions:
 */

int etnaviv_gpu_get_param(struct etnaviv_gpu *gpu, u32 param, u64 *value)
{
        switch (param) {
        case ETNAVIV_PARAM_GPU_MODEL:
                *value = gpu->identity.model;
                break;

        case ETNAVIV_PARAM_GPU_REVISION:
                *value = gpu->identity.revision;
                break;

        case ETNAVIV_PARAM_GPU_FEATURES_0:
                *value = gpu->identity.features;
                break;

        case ETNAVIV_PARAM_GPU_FEATURES_1:
                *value = gpu->identity.minor_features0;
                break;

        case ETNAVIV_PARAM_GPU_FEATURES_2:
                *value = gpu->identity.minor_features1;
                break;

        case ETNAVIV_PARAM_GPU_FEATURES_3:
                *value = gpu->identity.minor_features2;
                break;

        case ETNAVIV_PARAM_GPU_FEATURES_4:
                *value = gpu->identity.minor_features3;
                break;

        case ETNAVIV_PARAM_GPU_FEATURES_5:
                *value = gpu->identity.minor_features4;
                break;

        case ETNAVIV_PARAM_GPU_FEATURES_6:
                *value = gpu->identity.minor_features5;
                break;

        case ETNAVIV_PARAM_GPU_STREAM_COUNT:
                *value = gpu->identity.stream_count;
                break;

        case ETNAVIV_PARAM_GPU_REGISTER_MAX:
                *value = gpu->identity.register_max;
                break;

        case ETNAVIV_PARAM_GPU_THREAD_COUNT:
                *value = gpu->identity.thread_count;
                break;

        case ETNAVIV_PARAM_GPU_VERTEX_CACHE_SIZE:
                *value = gpu->identity.vertex_cache_size;
                break;

        case ETNAVIV_PARAM_GPU_SHADER_CORE_COUNT:
                *value = gpu->identity.shader_core_count;
                break;

        case ETNAVIV_PARAM_GPU_PIXEL_PIPES:
                *value = gpu->identity.pixel_pipes;
                break;

        case ETNAVIV_PARAM_GPU_VERTEX_OUTPUT_BUFFER_SIZE:
                *value = gpu->identity.vertex_output_buffer_size;
                break;

        case ETNAVIV_PARAM_GPU_BUFFER_SIZE:
                *value = gpu->identity.buffer_size;
                break;

        case ETNAVIV_PARAM_GPU_INSTRUCTION_COUNT:
                *value = gpu->identity.instruction_count;
                break;

        case ETNAVIV_PARAM_GPU_NUM_CONSTANTS:
                *value = gpu->identity.num_constants;
                break;

        case ETNAVIV_PARAM_GPU_NUM_VARYINGS:
                *value = gpu->identity.varyings_count;
                break;

        default:
                DBG("%s: invalid param: %u", dev_name(gpu->dev), param);
                return -EINVAL;
        }

        return 0;
}


#define etnaviv_is_model_rev(gpu, mod, rev) \
        ((gpu)->identity.model == chipModel_##mod && \
         (gpu)->identity.revision == rev)
#define etnaviv_field(val, field) \
        (((val) & field##__MASK) >> field##__SHIFT)

static void etnaviv_hw_specs(struct etnaviv_gpu *gpu)
{
        if (gpu->identity.minor_features0 &
            chipMinorFeatures0_MORE_MINOR_FEATURES) {
                u32 specs[4];
                unsigned int streams;

                specs[0] = gpu_read(gpu, VIVS_HI_CHIP_SPECS);
                specs[1] = gpu_read(gpu, VIVS_HI_CHIP_SPECS_2);
                specs[2] = gpu_read(gpu, VIVS_HI_CHIP_SPECS_3);
                specs[3] = gpu_read(gpu, VIVS_HI_CHIP_SPECS_4);

                gpu->identity.stream_count = etnaviv_field(specs[0],
                                        VIVS_HI_CHIP_SPECS_STREAM_COUNT);
                gpu->identity.register_max = etnaviv_field(specs[0],
                                        VIVS_HI_CHIP_SPECS_REGISTER_MAX);
                gpu->identity.thread_count = etnaviv_field(specs[0],
                                        VIVS_HI_CHIP_SPECS_THREAD_COUNT);
                gpu->identity.vertex_cache_size = etnaviv_field(specs[0],
                                        VIVS_HI_CHIP_SPECS_VERTEX_CACHE_SIZE);
                gpu->identity.shader_core_count = etnaviv_field(specs[0],
                                        VIVS_HI_CHIP_SPECS_SHADER_CORE_COUNT);
                gpu->identity.pixel_pipes = etnaviv_field(specs[0],
                                        VIVS_HI_CHIP_SPECS_PIXEL_PIPES);
                gpu->identity.vertex_output_buffer_size =
                        etnaviv_field(specs[0],
                                VIVS_HI_CHIP_SPECS_VERTEX_OUTPUT_BUFFER_SIZE);

                gpu->identity.buffer_size = etnaviv_field(specs[1],
                                        VIVS_HI_CHIP_SPECS_2_BUFFER_SIZE);
                gpu->identity.instruction_count = etnaviv_field(specs[1],
                                        VIVS_HI_CHIP_SPECS_2_INSTRUCTION_COUNT);
                gpu->identity.num_constants = etnaviv_field(specs[1],
                                        VIVS_HI_CHIP_SPECS_2_NUM_CONSTANTS);

                gpu->identity.varyings_count = etnaviv_field(specs[2],
                                        VIVS_HI_CHIP_SPECS_3_VARYINGS_COUNT);

                /* This overrides the value from older register if non-zero */
                streams = etnaviv_field(specs[3],
                                        VIVS_HI_CHIP_SPECS_4_STREAM_COUNT);
                if (streams)
                        gpu->identity.stream_count = streams;
        }

        /* Fill in the stream count if not specified */
        if (gpu->identity.stream_count == 0) {
                if (gpu->identity.model >= 0x1000)
                        gpu->identity.stream_count = 4;
                else
                        gpu->identity.stream_count = 1;
        }

        /* Convert the register max value */
        if (gpu->identity.register_max)
                gpu->identity.register_max = 1 << gpu->identity.register_max;
        else if (gpu->identity.model == chipModel_GC400)
                gpu->identity.register_max = 32;
        else
                gpu->identity.register_max = 64;

        /* Convert thread count */
        if (gpu->identity.thread_count)
                gpu->identity.thread_count = 1 << gpu->identity.thread_count;
        else if (gpu->identity.model == chipModel_GC400)
                gpu->identity.thread_count = 64;
        else if (gpu->identity.model == chipModel_GC500 ||
                 gpu->identity.model == chipModel_GC530)
                gpu->identity.thread_count = 128;
        else
                gpu->identity.thread_count = 256;

        if (gpu->identity.vertex_cache_size == 0)
                gpu->identity.vertex_cache_size = 8;

        if (gpu->identity.shader_core_count == 0) {
                if (gpu->identity.model >= 0x1000)
                        gpu->identity.shader_core_count = 2;
                else
                        gpu->identity.shader_core_count = 1;
        }

        if (gpu->identity.pixel_pipes == 0)
                gpu->identity.pixel_pipes = 1;

        /* Convert virtex buffer size */
        if (gpu->identity.vertex_output_buffer_size) {
                gpu->identity.vertex_output_buffer_size =
                        1 << gpu->identity.vertex_output_buffer_size;
        } else if (gpu->identity.model == chipModel_GC400) {
                if (gpu->identity.revision < 0x4000)
                        gpu->identity.vertex_output_buffer_size = 512;
                else if (gpu->identity.revision < 0x4200)
                        gpu->identity.vertex_output_buffer_size = 256;
                else
                        gpu->identity.vertex_output_buffer_size = 128;
        } else {
                gpu->identity.vertex_output_buffer_size = 512;
        }

        switch (gpu->identity.instruction_count) {
        case 0:
                if (etnaviv_is_model_rev(gpu, GC2000, 0x5108) ||
                    gpu->identity.model == chipModel_GC880)
                        gpu->identity.instruction_count = 512;
                else
                        gpu->identity.instruction_count = 256;
                break;

        case 1:
                gpu->identity.instruction_count = 1024;
                break;

        case 2:
                gpu->identity.instruction_count = 2048;
                break;

        default:
                gpu->identity.instruction_count = 256;
                break;
        }

        if (gpu->identity.num_constants == 0)
                gpu->identity.num_constants = 168;

        if (gpu->identity.varyings_count == 0) {
                if (gpu->identity.minor_features1 & chipMinorFeatures1_HALTI0)
                        gpu->identity.varyings_count = 12;
                else
                        gpu->identity.varyings_count = 8;
        }

        /*
         * For some cores, two varyings are consumed for position, so the
         * maximum varying count needs to be reduced by one.
         */
        if (etnaviv_is_model_rev(gpu, GC5000, 0x5434) ||
            etnaviv_is_model_rev(gpu, GC4000, 0x5222) ||
            etnaviv_is_model_rev(gpu, GC4000, 0x5245) ||
            etnaviv_is_model_rev(gpu, GC4000, 0x5208) ||
            etnaviv_is_model_rev(gpu, GC3000, 0x5435) ||
            etnaviv_is_model_rev(gpu, GC2200, 0x5244) ||
            etnaviv_is_model_rev(gpu, GC2100, 0x5108) ||
            etnaviv_is_model_rev(gpu, GC2000, 0x5108) ||
            etnaviv_is_model_rev(gpu, GC1500, 0x5246) ||
            etnaviv_is_model_rev(gpu, GC880, 0x5107) ||
            etnaviv_is_model_rev(gpu, GC880, 0x5106))
                gpu->identity.varyings_count -= 1;
}

static void etnaviv_hw_identify(struct etnaviv_gpu *gpu)
{
        u32 chipIdentity;

        chipIdentity = gpu_read(gpu, VIVS_HI_CHIP_IDENTITY);

        /* Special case for older graphic cores. */
        if (etnaviv_field(chipIdentity, VIVS_HI_CHIP_IDENTITY_FAMILY) == 0x01) {
                gpu->identity.model    = chipModel_GC500;
                gpu->identity.revision = etnaviv_field(chipIdentity,
                                         VIVS_HI_CHIP_IDENTITY_REVISION);
        } else {

                gpu->identity.model = gpu_read(gpu, VIVS_HI_CHIP_MODEL);
                gpu->identity.revision = gpu_read(gpu, VIVS_HI_CHIP_REV);

                /*
                 * !!!! HACK ALERT !!!!
                 * Because people change device IDs without letting software
                 * know about it - here is the hack to make it all look the
                 * same.  Only for GC400 family.
                 */
                if ((gpu->identity.model & 0xff00) == 0x0400 &&
                    gpu->identity.model != chipModel_GC420) {
                        gpu->identity.model = gpu->identity.model & 0x0400;
                }

                /* Another special case */
                if (etnaviv_is_model_rev(gpu, GC300, 0x2201)) {
                        u32 chipDate = gpu_read(gpu, VIVS_HI_CHIP_DATE);
                        u32 chipTime = gpu_read(gpu, VIVS_HI_CHIP_TIME);

                        if (chipDate == 0x20080814 && chipTime == 0x12051100) {
                                /*
                                 * This IP has an ECO; put the correct
                                 * revision in it.
                                 */
                                gpu->identity.revision = 0x1051;
                        }
                }

                /*
                 * NXP likes to call the GPU on the i.MX6QP GC2000+, but in
                 * reality it's just a re-branded GC3000. We can identify this
                 * core by the upper half of the revision register being all 1.
                 * Fix model/rev here, so all other places can refer to this
                 * core by its real identity.
                 */
                if (etnaviv_is_model_rev(gpu, GC2000, 0xffff5450)) {
                        gpu->identity.model = chipModel_GC3000;
                        gpu->identity.revision &= 0xffff;
                }
        }

        dev_info(gpu->dev, "model: GC%x, revision: %x\n",
                 gpu->identity.model, gpu->identity.revision);

        gpu->identity.features = gpu_read(gpu, VIVS_HI_CHIP_FEATURE);

        /* Disable fast clear on GC700. */
        if (gpu->identity.model == chipModel_GC700)
                gpu->identity.features &= ~chipFeatures_FAST_CLEAR;

        if ((gpu->identity.model == chipModel_GC500 &&
             gpu->identity.revision < 2) ||
            (gpu->identity.model == chipModel_GC300 &&
             gpu->identity.revision < 0x2000)) {

                /*
                 * GC500 rev 1.x and GC300 rev < 2.0 doesn't have these
                 * registers.
                 */
                gpu->identity.minor_features0 = 0;
                gpu->identity.minor_features1 = 0;
                gpu->identity.minor_features2 = 0;
                gpu->identity.minor_features3 = 0;
                gpu->identity.minor_features4 = 0;
                gpu->identity.minor_features5 = 0;
        } else
                gpu->identity.minor_features0 =
                                gpu_read(gpu, VIVS_HI_CHIP_MINOR_FEATURE_0);

        if (gpu->identity.minor_features0 &
            chipMinorFeatures0_MORE_MINOR_FEATURES) {
                gpu->identity.minor_features1 =
                                gpu_read(gpu, VIVS_HI_CHIP_MINOR_FEATURE_1);
                gpu->identity.minor_features2 =
                                gpu_read(gpu, VIVS_HI_CHIP_MINOR_FEATURE_2);
                gpu->identity.minor_features3 =
                                gpu_read(gpu, VIVS_HI_CHIP_MINOR_FEATURE_3);
                gpu->identity.minor_features4 =
                                gpu_read(gpu, VIVS_HI_CHIP_MINOR_FEATURE_4);
                gpu->identity.minor_features5 =
                                gpu_read(gpu, VIVS_HI_CHIP_MINOR_FEATURE_5);
        }

        /* GC600 idle register reports zero bits where modules aren't present */
        if (gpu->identity.model == chipModel_GC600) {
                gpu->idle_mask = VIVS_HI_IDLE_STATE_TX |
                                 VIVS_HI_IDLE_STATE_RA |
                                 VIVS_HI_IDLE_STATE_SE |
                                 VIVS_HI_IDLE_STATE_PA |
                                 VIVS_HI_IDLE_STATE_SH |
                                 VIVS_HI_IDLE_STATE_PE |
                                 VIVS_HI_IDLE_STATE_DE |
                                 VIVS_HI_IDLE_STATE_FE;
        } else {
                gpu->idle_mask = ~VIVS_HI_IDLE_STATE_AXI_LP;
        }

        etnaviv_hw_specs(gpu);
}

static void etnaviv_gpu_load_clock(struct etnaviv_gpu *gpu, u32 clock)
{
        gpu_write(gpu, VIVS_HI_CLOCK_CONTROL, clock |
                  VIVS_HI_CLOCK_CONTROL_FSCALE_CMD_LOAD);
        gpu_write(gpu, VIVS_HI_CLOCK_CONTROL, clock);
}

static int etnaviv_hw_reset(struct etnaviv_gpu *gpu)
{
        u32 control, idle;
        unsigned long timeout;
        bool failed = true;

        /* TODO
         *
         * - clock gating
         * - puls eater
         * - what about VG?
         */

        /* We hope that the GPU resets in under one second */
        timeout = jiffies + msecs_to_jiffies(1000);

        while (time_is_after_jiffies(timeout)) {
                control = VIVS_HI_CLOCK_CONTROL_DISABLE_DEBUG_REGISTERS |
                          VIVS_HI_CLOCK_CONTROL_FSCALE_VAL(0x40);

                /* enable clock */
                etnaviv_gpu_load_clock(gpu, control);

                /* Wait for stable clock.  Vivante's code waited for 1ms */
                usleep_range(1000, 10000);

                /* isolate the GPU. */
                control |= VIVS_HI_CLOCK_CONTROL_ISOLATE_GPU;
                gpu_write(gpu, VIVS_HI_CLOCK_CONTROL, control);

                /* set soft reset. */
                control |= VIVS_HI_CLOCK_CONTROL_SOFT_RESET;
                gpu_write(gpu, VIVS_HI_CLOCK_CONTROL, control);

                /* wait for reset. */
                msleep(1);

                /* reset soft reset bit. */
                control &= ~VIVS_HI_CLOCK_CONTROL_SOFT_RESET;
                gpu_write(gpu, VIVS_HI_CLOCK_CONTROL, control);

                /* reset GPU isolation. */
                control &= ~VIVS_HI_CLOCK_CONTROL_ISOLATE_GPU;
                gpu_write(gpu, VIVS_HI_CLOCK_CONTROL, control);

                /* read idle register. */
                idle = gpu_read(gpu, VIVS_HI_IDLE_STATE);

                /* try reseting again if FE it not idle */
                if ((idle & VIVS_HI_IDLE_STATE_FE) == 0) {
                        dev_dbg(gpu->dev, "FE is not idle\n");
                        continue;
                }

                /* read reset register. */
                control = gpu_read(gpu, VIVS_HI_CLOCK_CONTROL);

                /* is the GPU idle? */
                if (((control & VIVS_HI_CLOCK_CONTROL_IDLE_3D) == 0) ||
                    ((control & VIVS_HI_CLOCK_CONTROL_IDLE_2D) == 0)) {
                        dev_dbg(gpu->dev, "GPU is not idle\n");
                        continue;
                }

                failed = false;
                break;
        }

        if (failed) {
                idle = gpu_read(gpu, VIVS_HI_IDLE_STATE);
                control = gpu_read(gpu, VIVS_HI_CLOCK_CONTROL);

                dev_err(gpu->dev, "GPU failed to reset: FE %sidle, 3D %sidle, 2D %sidle\n",
                        idle & VIVS_HI_IDLE_STATE_FE ? "" : "not ",
                        control & VIVS_HI_CLOCK_CONTROL_IDLE_3D ? "" : "not ",
                        control & VIVS_HI_CLOCK_CONTROL_IDLE_2D ? "" : "not ");

                return -EBUSY;
        }

        /* We rely on the GPU running, so program the clock */
        control = VIVS_HI_CLOCK_CONTROL_DISABLE_DEBUG_REGISTERS |
                  VIVS_HI_CLOCK_CONTROL_FSCALE_VAL(0x40);

        /* enable clock */
        etnaviv_gpu_load_clock(gpu, control);

        return 0;
}

static void etnaviv_gpu_enable_mlcg(struct etnaviv_gpu *gpu)
{
        u32 pmc, ppc;

        /* enable clock gating */
        ppc = gpu_read(gpu, VIVS_PM_POWER_CONTROLS);
        ppc |= VIVS_PM_POWER_CONTROLS_ENABLE_MODULE_CLOCK_GATING;

        /* Disable stall module clock gating for 4.3.0.1 and 4.3.0.2 revs */
        if (gpu->identity.revision == 0x4301 ||
            gpu->identity.revision == 0x4302)
                ppc |= VIVS_PM_POWER_CONTROLS_DISABLE_STALL_MODULE_CLOCK_GATING;

        gpu_write(gpu, VIVS_PM_POWER_CONTROLS, ppc);

        pmc = gpu_read(gpu, VIVS_PM_MODULE_CONTROLS);

        /* Disable PA clock gating for GC400+ except for GC420 */
        if (gpu->identity.model >= chipModel_GC400 &&
            gpu->identity.model != chipModel_GC420)
                pmc |= VIVS_PM_MODULE_CONTROLS_DISABLE_MODULE_CLOCK_GATING_PA;

        /*
         * Disable PE clock gating on revs < 5.0.0.0 when HZ is
         * present without a bug fix.
         */
        if (gpu->identity.revision < 0x5000 &&
            gpu->identity.minor_features0 & chipMinorFeatures0_HZ &&
            !(gpu->identity.minor_features1 &
              chipMinorFeatures1_DISABLE_PE_GATING))
                pmc |= VIVS_PM_MODULE_CONTROLS_DISABLE_MODULE_CLOCK_GATING_PE;

        if (gpu->identity.revision < 0x5422)
                pmc |= BIT(15); /* Unknown bit */

        pmc |= VIVS_PM_MODULE_CONTROLS_DISABLE_MODULE_CLOCK_GATING_RA_HZ;
        pmc |= VIVS_PM_MODULE_CONTROLS_DISABLE_MODULE_CLOCK_GATING_RA_EZ;

        gpu_write(gpu, VIVS_PM_MODULE_CONTROLS, pmc);
}

void etnaviv_gpu_start_fe(struct etnaviv_gpu *gpu, u32 address, u16 prefetch)
{
        gpu_write(gpu, VIVS_FE_COMMAND_ADDRESS, address);
        gpu_write(gpu, VIVS_FE_COMMAND_CONTROL,
                  VIVS_FE_COMMAND_CONTROL_ENABLE |
                  VIVS_FE_COMMAND_CONTROL_PREFETCH(prefetch));
}

static void etnaviv_gpu_setup_pulse_eater(struct etnaviv_gpu *gpu)
{
        /*
         * Base value for VIVS_PM_PULSE_EATER register on models where it
         * cannot be read, extracted from vivante kernel driver.
         */
        u32 pulse_eater = 0x01590880;

        if (etnaviv_is_model_rev(gpu, GC4000, 0x5208) ||
            etnaviv_is_model_rev(gpu, GC4000, 0x5222)) {
                pulse_eater |= BIT(23);

        }

        if (etnaviv_is_model_rev(gpu, GC1000, 0x5039) ||
            etnaviv_is_model_rev(gpu, GC1000, 0x5040)) {
                pulse_eater &= ~BIT(16);
                pulse_eater |= BIT(17);
        }

        if ((gpu->identity.revision > 0x5420) &&
            (gpu->identity.features & chipFeatures_PIPE_3D))
        {
                /* Performance fix: disable internal DFS */
                pulse_eater = gpu_read(gpu, VIVS_PM_PULSE_EATER);
                pulse_eater |= BIT(18);
        }

        gpu_write(gpu, VIVS_PM_PULSE_EATER, pulse_eater);
}

static void etnaviv_gpu_hw_init(struct etnaviv_gpu *gpu)
{
        u16 prefetch;

        if ((etnaviv_is_model_rev(gpu, GC320, 0x5007) ||
             etnaviv_is_model_rev(gpu, GC320, 0x5220)) &&
            gpu_read(gpu, VIVS_HI_CHIP_TIME) != 0x2062400) {
                u32 mc_memory_debug;

                mc_memory_debug = gpu_read(gpu, VIVS_MC_DEBUG_MEMORY) & ~0xff;

                if (gpu->identity.revision == 0x5007)
                        mc_memory_debug |= 0x0c;
                else
                        mc_memory_debug |= 0x08;

                gpu_write(gpu, VIVS_MC_DEBUG_MEMORY, mc_memory_debug);
        }

        /* enable module-level clock gating */
        etnaviv_gpu_enable_mlcg(gpu);

        /*
         * Update GPU AXI cache atttribute to "cacheable, no allocate".
         * This is necessary to prevent the iMX6 SoC locking up.
         */
        gpu_write(gpu, VIVS_HI_AXI_CONFIG,
                  VIVS_HI_AXI_CONFIG_AWCACHE(2) |
                  VIVS_HI_AXI_CONFIG_ARCACHE(2));

        /* GC2000 rev 5108 needs a special bus config */
        if (etnaviv_is_model_rev(gpu, GC2000, 0x5108)) {
                u32 bus_config = gpu_read(gpu, VIVS_MC_BUS_CONFIG);
                bus_config &= ~(VIVS_MC_BUS_CONFIG_FE_BUS_CONFIG__MASK |
                                VIVS_MC_BUS_CONFIG_TX_BUS_CONFIG__MASK);
                bus_config |= VIVS_MC_BUS_CONFIG_FE_BUS_CONFIG(1) |
                              VIVS_MC_BUS_CONFIG_TX_BUS_CONFIG(0);
                gpu_write(gpu, VIVS_MC_BUS_CONFIG, bus_config);
        }

        /* setup the pulse eater */
        etnaviv_gpu_setup_pulse_eater(gpu);

        /* setup the MMU */
        etnaviv_iommu_restore(gpu);

        /* Start command processor */
        prefetch = etnaviv_buffer_init(gpu);

        gpu_write(gpu, VIVS_HI_INTR_ENBL, ~0U);
        etnaviv_gpu_start_fe(gpu, etnaviv_cmdbuf_get_va(gpu->buffer),
                             prefetch);
}

int etnaviv_gpu_init(struct etnaviv_gpu *gpu)
{
        int ret, i;

        ret = pm_runtime_get_sync(gpu->dev);
        if (ret < 0) {
                dev_err(gpu->dev, "Failed to enable GPU power domain\n");
                return ret;
        }

        etnaviv_hw_identify(gpu);

        if (gpu->identity.model == 0) {
                dev_err(gpu->dev, "Unknown GPU model\n");
                ret = -ENXIO;
                goto fail;
        }

        /* Exclude VG cores with FE2.0 */
        if (gpu->identity.features & chipFeatures_PIPE_VG &&
            gpu->identity.features & chipFeatures_FE20) {
                dev_info(gpu->dev, "Ignoring GPU with VG and FE2.0\n");
                ret = -ENXIO;
                goto fail;
        }

        /*
         * Set the GPU linear window to be at the end of the DMA window, where
         * the CMA area is likely to reside. This ensures that we are able to
         * map the command buffers while having the linear window overlap as
         * much RAM as possible, so we can optimize mappings for other buffers.
         *
         * For 3D cores only do this if MC2.0 is present, as with MC1.0 it leads
         * to different views of the memory on the individual engines.
         */
        if (!(gpu->identity.features & chipFeatures_PIPE_3D) ||
            (gpu->identity.minor_features0 & chipMinorFeatures0_MC20)) {
                u32 dma_mask = (u32)dma_get_required_mask(gpu->dev);
                if (dma_mask < PHYS_OFFSET + SZ_2G)
                        gpu->memory_base = PHYS_OFFSET;
                else
                        gpu->memory_base = dma_mask - SZ_2G + 1;
        } else if (PHYS_OFFSET >= SZ_2G) {
                dev_info(gpu->dev, "Need to move linear window on MC1.0, disabling TS\n");
                gpu->memory_base = PHYS_OFFSET;
                gpu->identity.features &= ~chipFeatures_FAST_CLEAR;
        }

        ret = etnaviv_hw_reset(gpu);
        if (ret) {
                dev_err(gpu->dev, "GPU reset failed\n");
                goto fail;
        }

        gpu->mmu = etnaviv_iommu_new(gpu);
        if (IS_ERR(gpu->mmu)) {
                dev_err(gpu->dev, "Failed to instantiate GPU IOMMU\n");
                ret = PTR_ERR(gpu->mmu);
                goto fail;
        }

        gpu->cmdbuf_suballoc = etnaviv_cmdbuf_suballoc_new(gpu);
        if (IS_ERR(gpu->cmdbuf_suballoc)) {
                dev_err(gpu->dev, "Failed to create cmdbuf suballocator\n");
                ret = PTR_ERR(gpu->cmdbuf_suballoc);
                goto fail;
        }

        /* Create buffer: */
        gpu->buffer = etnaviv_cmdbuf_new(gpu->cmdbuf_suballoc, PAGE_SIZE, 0);
        if (!gpu->buffer) {
                ret = -ENOMEM;
                dev_err(gpu->dev, "could not create command buffer\n");
                goto destroy_iommu;
        }

        if (gpu->mmu->version == ETNAVIV_IOMMU_V1 &&
            etnaviv_cmdbuf_get_va(gpu->buffer) > 0x80000000) {
                ret = -EINVAL;
                dev_err(gpu->dev,
                        "command buffer outside valid memory window\n");
                goto free_buffer;
        }

        /* Setup event management */
        spin_lock_init(&gpu->event_spinlock);
        init_completion(&gpu->event_free);
        for (i = 0; i < ARRAY_SIZE(gpu->event); i++) {
                gpu->event[i].used = false;
                complete(&gpu->event_free);
        }

        /* Now program the hardware */
        mutex_lock(&gpu->lock);
        etnaviv_gpu_hw_init(gpu);
        gpu->exec_state = -1;
        mutex_unlock(&gpu->lock);

        pm_runtime_mark_last_busy(gpu->dev);
        pm_runtime_put_autosuspend(gpu->dev);

        return 0;

free_buffer:
        etnaviv_cmdbuf_free(gpu->buffer);
        gpu->buffer = NULL;
destroy_iommu:
        etnaviv_iommu_destroy(gpu->mmu);
        gpu->mmu = NULL;
fail:
        pm_runtime_mark_last_busy(gpu->dev);
        pm_runtime_put_autosuspend(gpu->dev);

        return ret;
}

#ifdef CONFIG_DEBUG_FS
struct dma_debug {
        u32 address[2];
        u32 state[2];
};

static void verify_dma(struct etnaviv_gpu *gpu, struct dma_debug *debug)
{
        u32 i;

        debug->address[0] = gpu_read(gpu, VIVS_FE_DMA_ADDRESS);
        debug->state[0]   = gpu_read(gpu, VIVS_FE_DMA_DEBUG_STATE);

        for (i = 0; i < 500; i++) {
                debug->address[1] = gpu_read(gpu, VIVS_FE_DMA_ADDRESS);
                debug->state[1]   = gpu_read(gpu, VIVS_FE_DMA_DEBUG_STATE);

                if (debug->address[0] != debug->address[1])
                        break;

                if (debug->state[0] != debug->state[1])
                        break;
        }
}

int etnaviv_gpu_debugfs(struct etnaviv_gpu *gpu, struct seq_file *m)
{
        struct dma_debug debug;
        u32 dma_lo, dma_hi, axi, idle;
        int ret;

        seq_printf(m, "%s Status:\n", dev_name(gpu->dev));

        ret = pm_runtime_get_sync(gpu->dev);
        if (ret < 0)
                return ret;

        dma_lo = gpu_read(gpu, VIVS_FE_DMA_LOW);
        dma_hi = gpu_read(gpu, VIVS_FE_DMA_HIGH);
        axi = gpu_read(gpu, VIVS_HI_AXI_STATUS);
        idle = gpu_read(gpu, VIVS_HI_IDLE_STATE);

        verify_dma(gpu, &debug);

        seq_puts(m, "\tfeatures\n");
        seq_printf(m, "\t minor_features0: 0x%08x\n",
                   gpu->identity.minor_features0);
        seq_printf(m, "\t minor_features1: 0x%08x\n",
                   gpu->identity.minor_features1);
        seq_printf(m, "\t minor_features2: 0x%08x\n",
                   gpu->identity.minor_features2);
        seq_printf(m, "\t minor_features3: 0x%08x\n",
                   gpu->identity.minor_features3);
        seq_printf(m, "\t minor_features4: 0x%08x\n",
                   gpu->identity.minor_features4);
        seq_printf(m, "\t minor_features5: 0x%08x\n",
                   gpu->identity.minor_features5);

        seq_puts(m, "\tspecs\n");
        seq_printf(m, "\t stream_count:  %d\n",
                        gpu->identity.stream_count);
        seq_printf(m, "\t register_max: %d\n",
                        gpu->identity.register_max);
        seq_printf(m, "\t thread_count: %d\n",
                        gpu->identity.thread_count);
        seq_printf(m, "\t vertex_cache_size: %d\n",
                        gpu->identity.vertex_cache_size);
        seq_printf(m, "\t shader_core_count: %d\n",
                        gpu->identity.shader_core_count);
        seq_printf(m, "\t pixel_pipes: %d\n",
                        gpu->identity.pixel_pipes);
        seq_printf(m, "\t vertex_output_buffer_size: %d\n",
                        gpu->identity.vertex_output_buffer_size);
        seq_printf(m, "\t buffer_size: %d\n",
                        gpu->identity.buffer_size);
        seq_printf(m, "\t instruction_count: %d\n",
                        gpu->identity.instruction_count);
        seq_printf(m, "\t num_constants: %d\n",
                        gpu->identity.num_constants);
        seq_printf(m, "\t varyings_count: %d\n",
                        gpu->identity.varyings_count);

        seq_printf(m, "\taxi: 0x%08x\n", axi);
        seq_printf(m, "\tidle: 0x%08x\n", idle);
        idle |= ~gpu->idle_mask & ~VIVS_HI_IDLE_STATE_AXI_LP;
        if ((idle & VIVS_HI_IDLE_STATE_FE) == 0)
                seq_puts(m, "\t FE is not idle\n");
        if ((idle & VIVS_HI_IDLE_STATE_DE) == 0)
                seq_puts(m, "\t DE is not idle\n");
        if ((idle & VIVS_HI_IDLE_STATE_PE) == 0)
                seq_puts(m, "\t PE is not idle\n");
        if ((idle & VIVS_HI_IDLE_STATE_SH) == 0)
                seq_puts(m, "\t SH is not idle\n");
        if ((idle & VIVS_HI_IDLE_STATE_PA) == 0)
                seq_puts(m, "\t PA is not idle\n");
        if ((idle & VIVS_HI_IDLE_STATE_SE) == 0)
                seq_puts(m, "\t SE is not idle\n");
        if ((idle & VIVS_HI_IDLE_STATE_RA) == 0)
                seq_puts(m, "\t RA is not idle\n");
        if ((idle & VIVS_HI_IDLE_STATE_TX) == 0)
                seq_puts(m, "\t TX is not idle\n");
        if ((idle & VIVS_HI_IDLE_STATE_VG) == 0)
                seq_puts(m, "\t VG is not idle\n");
        if ((idle & VIVS_HI_IDLE_STATE_IM) == 0)
                seq_puts(m, "\t IM is not idle\n");
        if ((idle & VIVS_HI_IDLE_STATE_FP) == 0)
                seq_puts(m, "\t FP is not idle\n");
        if ((idle & VIVS_HI_IDLE_STATE_TS) == 0)
                seq_puts(m, "\t TS is not idle\n");
        if (idle & VIVS_HI_IDLE_STATE_AXI_LP)
                seq_puts(m, "\t AXI low power mode\n");

        if (gpu->identity.features & chipFeatures_DEBUG_MODE) {
                u32 read0 = gpu_read(gpu, VIVS_MC_DEBUG_READ0);
                u32 read1 = gpu_read(gpu, VIVS_MC_DEBUG_READ1);
                u32 write = gpu_read(gpu, VIVS_MC_DEBUG_WRITE);

                seq_puts(m, "\tMC\n");
                seq_printf(m, "\t read0: 0x%08x\n", read0);
                seq_printf(m, "\t read1: 0x%08x\n", read1);
                seq_printf(m, "\t write: 0x%08x\n", write);
        }

        seq_puts(m, "\tDMA ");

        if (debug.address[0] == debug.address[1] &&
            debug.state[0] == debug.state[1]) {
                seq_puts(m, "seems to be stuck\n");
        } else if (debug.address[0] == debug.address[1]) {
                seq_puts(m, "address is constant\n");
        } else {
                seq_puts(m, "is running\n");
        }

        seq_printf(m, "\t address 0: 0x%08x\n", debug.address[0]);
        seq_printf(m, "\t address 1: 0x%08x\n", debug.address[1]);
        seq_printf(m, "\t state 0: 0x%08x\n", debug.state[0]);
        seq_printf(m, "\t state 1: 0x%08x\n", debug.state[1]);
        seq_printf(m, "\t last fetch 64 bit word: 0x%08x 0x%08x\n",
                   dma_lo, dma_hi);

        ret = 0;

        pm_runtime_mark_last_busy(gpu->dev);
        pm_runtime_put_autosuspend(gpu->dev);

        return ret;
}
#endif

/*
 * Hangcheck detection for locked gpu:
 */
static void recover_worker(struct work_struct *work)
{
        struct etnaviv_gpu *gpu = container_of(work, struct etnaviv_gpu,
                                               recover_work);
        unsigned long flags;
        unsigned int i;

        dev_err(gpu->dev, "hangcheck recover!\n");

        if (pm_runtime_get_sync(gpu->dev) < 0)
                return;

        mutex_lock(&gpu->lock);

        /* Only catch the first event, or when manually re-armed */
        if (etnaviv_dump_core) {
                etnaviv_core_dump(gpu);
                etnaviv_dump_core = false;
        }

        etnaviv_hw_reset(gpu);

        /* complete all events, the GPU won't do it after the reset */
        spin_lock_irqsave(&gpu->event_spinlock, flags);
        for (i = 0; i < ARRAY_SIZE(gpu->event); i++) {
                if (!gpu->event[i].used)
                        continue;
                dma_fence_signal(gpu->event[i].fence);
                gpu->event[i].fence = NULL;
                gpu->event[i].used = false;
                complete(&gpu->event_free);
        }
        spin_unlock_irqrestore(&gpu->event_spinlock, flags);
        gpu->completed_fence = gpu->active_fence;

        etnaviv_gpu_hw_init(gpu);
        gpu->lastctx = NULL;
        gpu->exec_state = -1;

        mutex_unlock(&gpu->lock);
        pm_runtime_mark_last_busy(gpu->dev);
        pm_runtime_put_autosuspend(gpu->dev);

        /* Retire the buffer objects in a work */
        etnaviv_queue_work(gpu->drm, &gpu->retire_work);
}

static void hangcheck_timer_reset(struct etnaviv_gpu *gpu)
{
        DBG("%s", dev_name(gpu->dev));
        mod_timer(&gpu->hangcheck_timer,
                  round_jiffies_up(jiffies + DRM_ETNAVIV_HANGCHECK_JIFFIES));
}

static void hangcheck_handler(unsigned long data)
{
        struct etnaviv_gpu *gpu = (struct etnaviv_gpu *)data;
        u32 fence = gpu->completed_fence;
        bool progress = false;

        if (fence != gpu->hangcheck_fence) {
                gpu->hangcheck_fence = fence;
                progress = true;
        }

        if (!progress) {
                u32 dma_addr = gpu_read(gpu, VIVS_FE_DMA_ADDRESS);
                int change = dma_addr - gpu->hangcheck_dma_addr;

                if (change < 0 || change > 16) {
                        gpu->hangcheck_dma_addr = dma_addr;
                        progress = true;
                }
        }

        if (!progress && fence_after(gpu->active_fence, fence)) {
                dev_err(gpu->dev, "hangcheck detected gpu lockup!\n");
                dev_err(gpu->dev, "     completed fence: %u\n", fence);
                dev_err(gpu->dev, "     active fence: %u\n",
                        gpu->active_fence);
                etnaviv_queue_work(gpu->drm, &gpu->recover_work);
        }

        /* if still more pending work, reset the hangcheck timer: */
        if (fence_after(gpu->active_fence, gpu->hangcheck_fence))
                hangcheck_timer_reset(gpu);
}

static void hangcheck_disable(struct etnaviv_gpu *gpu)
{
        del_timer_sync(&gpu->hangcheck_timer);
        cancel_work_sync(&gpu->recover_work);
}

/* fence object management */
struct etnaviv_fence {

        struct etnaviv_gpu *gpu;
        struct dma_fence base;
};

static inline struct etnaviv_fence *to_etnaviv_fence(struct dma_fence *fence)
{
        return container_of(fence, struct etnaviv_fence, base);
}

static const char *etnaviv_fence_get_driver_name(struct dma_fence *fence)
{
        return "etnaviv";
}

static const char *etnaviv_fence_get_timeline_name(struct dma_fence *fence)
{
        struct etnaviv_fence *f = to_etnaviv_fence(fence);

        return dev_name(f->gpu->dev);
}

static bool etnaviv_fence_enable_signaling(struct dma_fence *fence)
{
        return true;
}

static bool etnaviv_fence_signaled(struct dma_fence *fence)
{
        struct etnaviv_fence *f = to_etnaviv_fence(fence);

        return fence_completed(f->gpu, f->base.seqno);
}

static void etnaviv_fence_release(struct dma_fence *fence)
{
        struct etnaviv_fence *f = to_etnaviv_fence(fence);

        kfree_rcu(f, base.rcu);
}

static const struct dma_fence_ops etnaviv_fence_ops = {
        .get_driver_name = etnaviv_fence_get_driver_name,
        .get_timeline_name = etnaviv_fence_get_timeline_name,
        .enable_signaling = etnaviv_fence_enable_signaling,
        .signaled = etnaviv_fence_signaled,
        .wait = dma_fence_default_wait,
        .release = etnaviv_fence_release,
};

static struct dma_fence *etnaviv_gpu_fence_alloc(struct etnaviv_gpu *gpu)
{
        struct etnaviv_fence *f;

        f = kzalloc(sizeof(*f), GFP_KERNEL);
        if (!f)
                return NULL;

        f->gpu = gpu;

        dma_fence_init(&f->base, &etnaviv_fence_ops, &gpu->fence_spinlock,
                       gpu->fence_context, ++gpu->next_fence);

        return &f->base;
}

int etnaviv_gpu_fence_sync_obj(struct etnaviv_gem_object *etnaviv_obj,
        unsigned int context, bool exclusive)
{
        struct reservation_object *robj = etnaviv_obj->resv;
        struct reservation_object_list *fobj;
        struct dma_fence *fence;
        int i, ret;

        if (!exclusive) {
                ret = reservation_object_reserve_shared(robj);
                if (ret)
                        return ret;
        }

        /*
         * If we have any shared fences, then the exclusive fence
         * should be ignored as it will already have been signalled.
         */
        fobj = reservation_object_get_list(robj);
        if (!fobj || fobj->shared_count == 0) {
                /* Wait on any existing exclusive fence which isn't our own */
                fence = reservation_object_get_excl(robj);
                if (fence && fence->context != context) {
                        ret = dma_fence_wait(fence, true);
                        if (ret)
                                return ret;
                }
        }

        if (!exclusive || !fobj)
                return 0;

        for (i = 0; i < fobj->shared_count; i++) {
                fence = rcu_dereference_protected(fobj->shared[i],
                                                reservation_object_held(robj));
                if (fence->context != context) {
                        ret = dma_fence_wait(fence, true);
                        if (ret)
                                return ret;
                }
        }

        return 0;
}

/*
 * event management:
 */

static unsigned int event_alloc(struct etnaviv_gpu *gpu)
{
        unsigned long ret, flags;
        unsigned int i, event = ~0U;

        ret = wait_for_completion_timeout(&gpu->event_free,
                                          msecs_to_jiffies(10 * 10000));
        if (!ret)
                dev_err(gpu->dev, "wait_for_completion_timeout failed");

        spin_lock_irqsave(&gpu->event_spinlock, flags);

        /* find first free event */
        for (i = 0; i < ARRAY_SIZE(gpu->event); i++) {
                if (gpu->event[i].used == false) {
                        gpu->event[i].used = true;
                        event = i;
                        break;
                }
        }

        spin_unlock_irqrestore(&gpu->event_spinlock, flags);

        return event;
}

static void event_free(struct etnaviv_gpu *gpu, unsigned int event)
{
        unsigned long flags;

        spin_lock_irqsave(&gpu->event_spinlock, flags);

        if (gpu->event[event].used == false) {
                dev_warn(gpu->dev, "event %u is already marked as free",
                         event);
                spin_unlock_irqrestore(&gpu->event_spinlock, flags);
        } else {
                gpu->event[event].used = false;
                spin_unlock_irqrestore(&gpu->event_spinlock, flags);

                complete(&gpu->event_free);
        }
}

/*
 * Cmdstream submission/retirement:
 */

static void retire_worker(struct work_struct *work)
{
        struct etnaviv_gpu *gpu = container_of(work, struct etnaviv_gpu,
                                               retire_work);
        u32 fence = gpu->completed_fence;
        struct etnaviv_cmdbuf *cmdbuf, *tmp;
        unsigned int i;

        mutex_lock(&gpu->lock);
        list_for_each_entry_safe(cmdbuf, tmp, &gpu->active_cmd_list, node) {
                if (!dma_fence_is_signaled(cmdbuf->fence))
                        break;

                list_del(&cmdbuf->node);
                dma_fence_put(cmdbuf->fence);

                for (i = 0; i < cmdbuf->nr_bos; i++) {
                        struct etnaviv_vram_mapping *mapping = cmdbuf->bo_map[i];
                        struct etnaviv_gem_object *etnaviv_obj = mapping->object;

                        atomic_dec(&etnaviv_obj->gpu_active);
                        /* drop the refcount taken in etnaviv_gpu_submit */
                        etnaviv_gem_mapping_unreference(mapping);
                }

                etnaviv_cmdbuf_free(cmdbuf);
                /*
                 * We need to balance the runtime PM count caused by
                 * each submission.  Upon submission, we increment
                 * the runtime PM counter, and allocate one event.
                 * So here, we put the runtime PM count for each
                 * completed event.
                 */
                pm_runtime_put_autosuspend(gpu->dev);
        }

        gpu->retired_fence = fence;

        mutex_unlock(&gpu->lock);

        wake_up_all(&gpu->fence_event);
}

int etnaviv_gpu_wait_fence_interruptible(struct etnaviv_gpu *gpu,
        u32 fence, struct timespec *timeout)
{
        int ret;

        if (fence_after(fence, gpu->next_fence)) {
                DRM_ERROR("waiting on invalid fence: %u (of %u)\n",
                                fence, gpu->next_fence);
                return -EINVAL;
        }

        if (!timeout) {
                /* No timeout was requested: just test for completion */
                ret = fence_completed(gpu, fence) ? 0 : -EBUSY;
        } else {
                unsigned long remaining = etnaviv_timeout_to_jiffies(timeout);

                ret = wait_event_interruptible_timeout(gpu->fence_event,
                                                fence_completed(gpu, fence),
                                                remaining);
                if (ret == 0) {
                        DBG("timeout waiting for fence: %u (retired: %u completed: %u)",
                                fence, gpu->retired_fence,
                                gpu->completed_fence);
                        ret = -ETIMEDOUT;
                } else if (ret != -ERESTARTSYS) {
                        ret = 0;
                }
        }

        return ret;
}

/*
 * Wait for an object to become inactive.  This, on it's own, is not race
 * free: the object is moved by the retire worker off the active list, and
 * then the iova is put.  Moreover, the object could be re-submitted just
 * after we notice that it's become inactive.
 *
 * Although the retirement happens under the gpu lock, we don't want to hold
 * that lock in this function while waiting.
 */
int etnaviv_gpu_wait_obj_inactive(struct etnaviv_gpu *gpu,
        struct etnaviv_gem_object *etnaviv_obj, struct timespec *timeout)
{
        unsigned long remaining;
        long ret;

        if (!timeout)
                return !is_active(etnaviv_obj) ? 0 : -EBUSY;

        remaining = etnaviv_timeout_to_jiffies(timeout);

        ret = wait_event_interruptible_timeout(gpu->fence_event,
                                               !is_active(etnaviv_obj),
                                               remaining);
        if (ret > 0) {
                struct etnaviv_drm_private *priv = gpu->drm->dev_private;

                /* Synchronise with the retire worker */
                flush_workqueue(priv->wq);
                return 0;
        } else if (ret == -ERESTARTSYS) {
                return -ERESTARTSYS;
        } else {
                return -ETIMEDOUT;
        }
}

int etnaviv_gpu_pm_get_sync(struct etnaviv_gpu *gpu)
{
        return pm_runtime_get_sync(gpu->dev);
}

void etnaviv_gpu_pm_put(struct etnaviv_gpu *gpu)
{
        pm_runtime_mark_last_busy(gpu->dev);
        pm_runtime_put_autosuspend(gpu->dev);
}

/* add bo's to gpu's ring, and kick gpu: */
int etnaviv_gpu_submit(struct etnaviv_gpu *gpu,
        struct etnaviv_gem_submit *submit, struct etnaviv_cmdbuf *cmdbuf)
{
        struct dma_fence *fence;
        unsigned int event, i;
        int ret;

        ret = etnaviv_gpu_pm_get_sync(gpu);
        if (ret < 0)
                return ret;

        /*
         * TODO
         *
         * - flush
         * - data endian
         * - prefetch
         *
         */

        event = event_alloc(gpu);
        if (unlikely(event == ~0U)) {
                DRM_ERROR("no free event\n");
                ret = -EBUSY;
                goto out_pm_put;
        }

        mutex_lock(&gpu->lock);

        fence = etnaviv_gpu_fence_alloc(gpu);
        if (!fence) {
                event_free(gpu, event);
                ret = -ENOMEM;
                goto out_unlock;
        }

        gpu->event[event].fence = fence;
        submit->fence = fence->seqno;
        gpu->active_fence = submit->fence;

        if (gpu->lastctx != cmdbuf->ctx) {
                gpu->mmu->need_flush = true;
                gpu->switch_context = true;
                gpu->lastctx = cmdbuf->ctx;
        }

        etnaviv_buffer_queue(gpu, event, cmdbuf);

        cmdbuf->fence = fence;
        list_add_tail(&cmdbuf->node, &gpu->active_cmd_list);

        /* We're committed to adding this command buffer, hold a PM reference */
        pm_runtime_get_noresume(gpu->dev);

        for (i = 0; i < submit->nr_bos; i++) {
                struct etnaviv_gem_object *etnaviv_obj = submit->bos[i].obj;

                /* Each cmdbuf takes a refcount on the mapping */
                etnaviv_gem_mapping_reference(submit->bos[i].mapping);
                cmdbuf->bo_map[i] = submit->bos[i].mapping;
                atomic_inc(&etnaviv_obj->gpu_active);

                if (submit->bos[i].flags & ETNA_SUBMIT_BO_WRITE)
                        reservation_object_add_excl_fence(etnaviv_obj->resv,
                                                          fence);
                else
                        reservation_object_add_shared_fence(etnaviv_obj->resv,
                                                            fence);
        }
        cmdbuf->nr_bos = submit->nr_bos;
        hangcheck_timer_reset(gpu);
        ret = 0;

out_unlock:
        mutex_unlock(&gpu->lock);

out_pm_put:
        etnaviv_gpu_pm_put(gpu);

        return ret;
}

/*
 * Init/Cleanup:
 */
static irqreturn_t irq_handler(int irq, void *data)
{
        struct etnaviv_gpu *gpu = data;
        irqreturn_t ret = IRQ_NONE;

        u32 intr = gpu_read(gpu, VIVS_HI_INTR_ACKNOWLEDGE);

        if (intr != 0) {
                int event;

                pm_runtime_mark_last_busy(gpu->dev);

                dev_dbg(gpu->dev, "intr 0x%08x\n", intr);

                if (intr & VIVS_HI_INTR_ACKNOWLEDGE_AXI_BUS_ERROR) {
                        dev_err(gpu->dev, "AXI bus error\n");
                        intr &= ~VIVS_HI_INTR_ACKNOWLEDGE_AXI_BUS_ERROR;
                }

                if (intr & VIVS_HI_INTR_ACKNOWLEDGE_MMU_EXCEPTION) {
                        int i;

                        dev_err_ratelimited(gpu->dev,
                                "MMU fault status 0x%08x\n",
                                gpu_read(gpu, VIVS_MMUv2_STATUS));
                        for (i = 0; i < 4; i++) {
                                dev_err_ratelimited(gpu->dev,
                                        "MMU %d fault addr 0x%08x\n",
                                        i, gpu_read(gpu,
                                        VIVS_MMUv2_EXCEPTION_ADDR(i)));
                        }
                        intr &= ~VIVS_HI_INTR_ACKNOWLEDGE_MMU_EXCEPTION;
                }

                while ((event = ffs(intr)) != 0) {
                        struct dma_fence *fence;

                        event -= 1;

                        intr &= ~(1 << event);

                        dev_dbg(gpu->dev, "event %u\n", event);

                        fence = gpu->event[event].fence;
                        gpu->event[event].fence = NULL;
                        dma_fence_signal(fence);

                        /*
                         * Events can be processed out of order.  Eg,
                         * - allocate and queue event 0
                         * - allocate event 1
                         * - event 0 completes, we process it
                         * - allocate and queue event 0
                         * - event 1 and event 0 complete
                         * we can end up processing event 0 first, then 1.
                         */
                        if (fence_after(fence->seqno, gpu->completed_fence))
                                gpu->completed_fence = fence->seqno;

                        event_free(gpu, event);
                }

                /* Retire the buffer objects in a work */
                etnaviv_queue_work(gpu->drm, &gpu->retire_work);

                ret = IRQ_HANDLED;
        }

        return ret;
}

static int etnaviv_gpu_clk_enable(struct etnaviv_gpu *gpu)
{
        int ret;

        if (gpu->clk_bus) {
                ret = clk_prepare_enable(gpu->clk_bus);
                if (ret)
                        return ret;
        }

        if (gpu->clk_core) {
                ret = clk_prepare_enable(gpu->clk_core);
                if (ret)
                        goto disable_clk_bus;
        }

        if (gpu->clk_shader) {
                ret = clk_prepare_enable(gpu->clk_shader);
                if (ret)
                        goto disable_clk_core;
        }

        return 0;

disable_clk_core:
        if (gpu->clk_core)
                clk_disable_unprepare(gpu->clk_core);
disable_clk_bus:
        if (gpu->clk_bus)
                clk_disable_unprepare(gpu->clk_bus);

        return ret;
}

static int etnaviv_gpu_clk_disable(struct etnaviv_gpu *gpu)
{
        if (gpu->clk_shader)
                clk_disable_unprepare(gpu->clk_shader);
        if (gpu->clk_core)
                clk_disable_unprepare(gpu->clk_core);
        if (gpu->clk_bus)
                clk_disable_unprepare(gpu->clk_bus);

        return 0;
}

int etnaviv_gpu_wait_idle(struct etnaviv_gpu *gpu, unsigned int timeout_ms)
{
        unsigned long timeout = jiffies + msecs_to_jiffies(timeout_ms);

        do {
                u32 idle = gpu_read(gpu, VIVS_HI_IDLE_STATE);

                if ((idle & gpu->idle_mask) == gpu->idle_mask)
                        return 0;

                if (time_is_before_jiffies(timeout)) {
                        dev_warn(gpu->dev,
                                 "timed out waiting for idle: idle=0x%x\n",
                                 idle);
                        return -ETIMEDOUT;
                }

                udelay(5);
        } while (1);
}

static int etnaviv_gpu_hw_suspend(struct etnaviv_gpu *gpu)
{
        if (gpu->buffer) {
                /* Replace the last WAIT with END */
                etnaviv_buffer_end(gpu);

                /*
                 * We know that only the FE is busy here, this should
                 * happen quickly (as the WAIT is only 200 cycles).  If
                 * we fail, just warn and continue.
                 */
                etnaviv_gpu_wait_idle(gpu, 100);
        }

        return etnaviv_gpu_clk_disable(gpu);
}

#ifdef CONFIG_PM
static int etnaviv_gpu_hw_resume(struct etnaviv_gpu *gpu)
{
        u32 clock;
        int ret;

        ret = mutex_lock_killable(&gpu->lock);
        if (ret)
                return ret;

        clock = VIVS_HI_CLOCK_CONTROL_DISABLE_DEBUG_REGISTERS |
                VIVS_HI_CLOCK_CONTROL_FSCALE_VAL(0x40);

        etnaviv_gpu_load_clock(gpu, clock);
        etnaviv_gpu_hw_init(gpu);

        gpu->switch_context = true;
        gpu->exec_state = -1;

        mutex_unlock(&gpu->lock);

        return 0;
}
#endif

static int etnaviv_gpu_bind(struct device *dev, struct device *master,
        void *data)
{
        struct drm_device *drm = data;
        struct etnaviv_drm_private *priv = drm->dev_private;
        struct etnaviv_gpu *gpu = dev_get_drvdata(dev);
        int ret;

#ifdef CONFIG_PM
        ret = pm_runtime_get_sync(gpu->dev);
#else
        ret = etnaviv_gpu_clk_enable(gpu);
#endif
        if (ret < 0)
                return ret;

        gpu->drm = drm;
        gpu->fence_context = dma_fence_context_alloc(1);
        spin_lock_init(&gpu->fence_spinlock);

        INIT_LIST_HEAD(&gpu->active_cmd_list);
        INIT_WORK(&gpu->retire_work, retire_worker);
        INIT_WORK(&gpu->recover_work, recover_worker);
        init_waitqueue_head(&gpu->fence_event);

        setup_deferrable_timer(&gpu->hangcheck_timer, hangcheck_handler,
                               (unsigned long)gpu);

        priv->gpu[priv->num_gpus++] = gpu;

        pm_runtime_mark_last_busy(gpu->dev);
        pm_runtime_put_autosuspend(gpu->dev);

        return 0;
}

static void etnaviv_gpu_unbind(struct device *dev, struct device *master,
        void *data)
{
        struct etnaviv_gpu *gpu = dev_get_drvdata(dev);

        DBG("%s", dev_name(gpu->dev));

        hangcheck_disable(gpu);

#ifdef CONFIG_PM
        pm_runtime_get_sync(gpu->dev);
        pm_runtime_put_sync_suspend(gpu->dev);
#else
        etnaviv_gpu_hw_suspend(gpu);
#endif

        if (gpu->buffer) {
                etnaviv_cmdbuf_free(gpu->buffer);
                gpu->buffer = NULL;
        }

        if (gpu->cmdbuf_suballoc) {
                etnaviv_cmdbuf_suballoc_destroy(gpu->cmdbuf_suballoc);
                gpu->cmdbuf_suballoc = NULL;
        }

        if (gpu->mmu) {
                etnaviv_iommu_destroy(gpu->mmu);
                gpu->mmu = NULL;
        }

        gpu->drm = NULL;
}

static const struct component_ops gpu_ops = {
        .bind = etnaviv_gpu_bind,
        .unbind = etnaviv_gpu_unbind,
};

static const struct of_device_id etnaviv_gpu_match[] = {
        {
                .compatible = "vivante,gc"
        },
        { /* sentinel */ }
};

static int etnaviv_gpu_platform_probe(struct platform_device *pdev)
{
        struct device *dev = &pdev->dev;
        struct etnaviv_gpu *gpu;
        int err;

        gpu = devm_kzalloc(dev, sizeof(*gpu), GFP_KERNEL);
        if (!gpu)
                return -ENOMEM;

        gpu->dev = &pdev->dev;
        mutex_init(&gpu->lock);

        /* Map registers: */
        gpu->mmio = etnaviv_ioremap(pdev, NULL, dev_name(gpu->dev));
        if (IS_ERR(gpu->mmio))
                return PTR_ERR(gpu->mmio);

        /* Get Interrupt: */
        gpu->irq = platform_get_irq(pdev, 0);
        if (gpu->irq < 0) {
                dev_err(dev, "failed to get irq: %d\n", gpu->irq);
                return gpu->irq;
        }

        err = devm_request_irq(&pdev->dev, gpu->irq, irq_handler, 0,
                               dev_name(gpu->dev), gpu);
        if (err) {
                dev_err(dev, "failed to request IRQ%u: %d\n", gpu->irq, err);
                return err;
        }

        /* Get Clocks: */
        gpu->clk_bus = devm_clk_get(&pdev->dev, "bus");
        DBG("clk_bus: %p", gpu->clk_bus);
        if (IS_ERR(gpu->clk_bus))
                gpu->clk_bus = NULL;

        gpu->clk_core = devm_clk_get(&pdev->dev, "core");
        DBG("clk_core: %p", gpu->clk_core);
        if (IS_ERR(gpu->clk_core))
                gpu->clk_core = NULL;

        gpu->clk_shader = devm_clk_get(&pdev->dev, "shader");
        DBG("clk_shader: %p", gpu->clk_shader);
        if (IS_ERR(gpu->clk_shader))
                gpu->clk_shader = NULL;

        /* TODO: figure out max mapped size */
        dev_set_drvdata(dev, gpu);

        /*
         * We treat the device as initially suspended.  The runtime PM
         * autosuspend delay is rather arbitary: no measurements have
         * yet been performed to determine an appropriate value.
         */
        pm_runtime_use_autosuspend(gpu->dev);
        pm_runtime_set_autosuspend_delay(gpu->dev, 200);
        pm_runtime_enable(gpu->dev);

        err = component_add(&pdev->dev, &gpu_ops);
        if (err < 0) {
                dev_err(&pdev->dev, "failed to register component: %d\n", err);
                return err;
        }

        return 0;
}

static int etnaviv_gpu_platform_remove(struct platform_device *pdev)
{
        component_del(&pdev->dev, &gpu_ops);
        pm_runtime_disable(&pdev->dev);
        return 0;
}

#ifdef CONFIG_PM
static int etnaviv_gpu_rpm_suspend(struct device *dev)
{
        struct etnaviv_gpu *gpu = dev_get_drvdata(dev);
        u32 idle, mask;

        /* If we have outstanding fences, we're not idle */
        if (gpu->completed_fence != gpu->active_fence)
                return -EBUSY;

        /* Check whether the hardware (except FE) is idle */
        mask = gpu->idle_mask & ~VIVS_HI_IDLE_STATE_FE;
        idle = gpu_read(gpu, VIVS_HI_IDLE_STATE) & mask;
        if (idle != mask)
                return -EBUSY;

        return etnaviv_gpu_hw_suspend(gpu);
}

static int etnaviv_gpu_rpm_resume(struct device *dev)
{
        struct etnaviv_gpu *gpu = dev_get_drvdata(dev);
        int ret;

        ret = etnaviv_gpu_clk_enable(gpu);
        if (ret)
                return ret;

        /* Re-initialise the basic hardware state */
        if (gpu->drm && gpu->buffer) {
                ret = etnaviv_gpu_hw_resume(gpu);
                if (ret) {
                        etnaviv_gpu_clk_disable(gpu);
                        return ret;
                }
        }

        return 0;
}
#endif

static const struct dev_pm_ops etnaviv_gpu_pm_ops = {
        SET_RUNTIME_PM_OPS(etnaviv_gpu_rpm_suspend, etnaviv_gpu_rpm_resume,
                           NULL)
};

struct platform_driver etnaviv_gpu_driver = {
        .driver = {
                .name = "etnaviv-gpu",
                .owner = THIS_MODULE,
                .pm = &etnaviv_gpu_pm_ops,
                .of_match_table = etnaviv_gpu_match,
        },
        .probe = etnaviv_gpu_platform_probe,
        .remove = etnaviv_gpu_platform_remove,
        .id_table = gpu_ids,
};