// SPDX-License-Identifier: MIT
/*
 * Copyright © 2016 Intel Corporation
 */

#include <drm/drm_print.h>

#include "gem/i915_gem_context.h"

#include "i915_drv.h"

#include "intel_breadcrumbs.h"
#include "intel_context.h"
#include "intel_engine.h"
#include "intel_engine_pm.h"
#include "intel_engine_user.h"
#include "intel_execlists_submission.h"
#include "intel_gt.h"
#include "intel_gt_requests.h"
#include "intel_gt_pm.h"
#include "intel_lrc_reg.h"
#include "intel_reset.h"
#include "intel_ring.h"
#include "uc/intel_guc_submission.h"

/* Haswell does have the CXT_SIZE register however it does not appear to be
 * valid. Now, docs explain in dwords what is in the context object. The full
 * size is 70720 bytes, however, the power context and execlist context will
 * never be saved (power context is stored elsewhere, and execlists don't work
 * on HSW) - so the final size, including the extra state required for the
 * Resource Streamer, is 66944 bytes, which rounds to 17 pages.
 */
#define HSW_CXT_TOTAL_SIZE              (17 * PAGE_SIZE)

#define DEFAULT_LR_CONTEXT_RENDER_SIZE  (22 * PAGE_SIZE)
#define GEN8_LR_CONTEXT_RENDER_SIZE     (20 * PAGE_SIZE)
#define GEN9_LR_CONTEXT_RENDER_SIZE     (22 * PAGE_SIZE)
#define GEN11_LR_CONTEXT_RENDER_SIZE    (14 * PAGE_SIZE)

#define GEN8_LR_CONTEXT_OTHER_SIZE      ( 2 * PAGE_SIZE)

#define MAX_MMIO_BASES 3
struct engine_info {
        u8 class;
        u8 instance;
        /* mmio bases table *must* be sorted in reverse graphics_ver order */
        struct engine_mmio_base {
                u32 graphics_ver : 8;
                u32 base : 24;
        } mmio_bases[MAX_MMIO_BASES];
};

static const struct engine_info intel_engines[] = {
        [RCS0] = {
                .class = RENDER_CLASS,
                .instance = 0,
                .mmio_bases = {
                        { .graphics_ver = 1, .base = RENDER_RING_BASE }
                },
        },
        [BCS0] = {
                .class = COPY_ENGINE_CLASS,
                .instance = 0,
                .mmio_bases = {
                        { .graphics_ver = 6, .base = BLT_RING_BASE }
                },
        },
        [VCS0] = {
                .class = VIDEO_DECODE_CLASS,
                .instance = 0,
                .mmio_bases = {
                        { .graphics_ver = 11, .base = GEN11_BSD_RING_BASE },
                        { .graphics_ver = 6, .base = GEN6_BSD_RING_BASE },
                        { .graphics_ver = 4, .base = BSD_RING_BASE }
                },
        },
        [VCS1] = {
                .class = VIDEO_DECODE_CLASS,
                .instance = 1,
                .mmio_bases = {
                        { .graphics_ver = 11, .base = GEN11_BSD2_RING_BASE },
                        { .graphics_ver = 8, .base = GEN8_BSD2_RING_BASE }
                },
        },
        [VCS2] = {
                .class = VIDEO_DECODE_CLASS,
                .instance = 2,
                .mmio_bases = {
                        { .graphics_ver = 11, .base = GEN11_BSD3_RING_BASE }
                },
        },
        [VCS3] = {
                .class = VIDEO_DECODE_CLASS,
                .instance = 3,
                .mmio_bases = {
                        { .graphics_ver = 11, .base = GEN11_BSD4_RING_BASE }
                },
        },
        [VCS4] = {
                .class = VIDEO_DECODE_CLASS,
                .instance = 4,
                .mmio_bases = {
                        { .graphics_ver = 12, .base = XEHP_BSD5_RING_BASE }
                },
        },
        [VCS5] = {
                .class = VIDEO_DECODE_CLASS,
                .instance = 5,
                .mmio_bases = {
                        { .graphics_ver = 12, .base = XEHP_BSD6_RING_BASE }
                },
        },
        [VCS6] = {
                .class = VIDEO_DECODE_CLASS,
                .instance = 6,
                .mmio_bases = {
                        { .graphics_ver = 12, .base = XEHP_BSD7_RING_BASE }
                },
        },
        [VCS7] = {
                .class = VIDEO_DECODE_CLASS,
                .instance = 7,
                .mmio_bases = {
                        { .graphics_ver = 12, .base = XEHP_BSD8_RING_BASE }
                },
        },
        [VECS0] = {
                .class = VIDEO_ENHANCEMENT_CLASS,
                .instance = 0,
                .mmio_bases = {
                        { .graphics_ver = 11, .base = GEN11_VEBOX_RING_BASE },
                        { .graphics_ver = 7, .base = VEBOX_RING_BASE }
                },
        },
        [VECS1] = {
                .class = VIDEO_ENHANCEMENT_CLASS,
                .instance = 1,
                .mmio_bases = {
                        { .graphics_ver = 11, .base = GEN11_VEBOX2_RING_BASE }
                },
        },
        [VECS2] = {
                .class = VIDEO_ENHANCEMENT_CLASS,
                .instance = 2,
                .mmio_bases = {
                        { .graphics_ver = 12, .base = XEHP_VEBOX3_RING_BASE }
                },
        },
        [VECS3] = {
                .class = VIDEO_ENHANCEMENT_CLASS,
                .instance = 3,
                .mmio_bases = {
                        { .graphics_ver = 12, .base = XEHP_VEBOX4_RING_BASE }
                },
        },
};

/**
 * intel_engine_context_size() - return the size of the context for an engine
 * @gt: the gt
 * @class: engine class
 *
 * Each engine class may require a different amount of space for a context
 * image.
 *
 * Return: size (in bytes) of an engine class specific context image
 *
 * Note: this size includes the HWSP, which is part of the context image
 * in LRC mode, but does not include the "shared data page" used with
 * GuC submission. The caller should account for this if using the GuC.
 */
u32 intel_engine_context_size(struct intel_gt *gt, u8 class)
{
        struct intel_uncore *uncore = gt->uncore;
        u32 cxt_size;

        BUILD_BUG_ON(I915_GTT_PAGE_SIZE != PAGE_SIZE);

        switch (class) {
        case RENDER_CLASS:
                switch (GRAPHICS_VER(gt->i915)) {
                default:
                        MISSING_CASE(GRAPHICS_VER(gt->i915));
                        return DEFAULT_LR_CONTEXT_RENDER_SIZE;
                case 12:
                case 11:
                        return GEN11_LR_CONTEXT_RENDER_SIZE;
                case 9:
                        return GEN9_LR_CONTEXT_RENDER_SIZE;
                case 8:
                        return GEN8_LR_CONTEXT_RENDER_SIZE;
                case 7:
                        if (IS_HASWELL(gt->i915))
                                return HSW_CXT_TOTAL_SIZE;

                        cxt_size = intel_uncore_read(uncore, GEN7_CXT_SIZE);
                        return round_up(GEN7_CXT_TOTAL_SIZE(cxt_size) * 64,
                                        PAGE_SIZE);
                case 6:
                        cxt_size = intel_uncore_read(uncore, CXT_SIZE);
                        return round_up(GEN6_CXT_TOTAL_SIZE(cxt_size) * 64,
                                        PAGE_SIZE);
                case 5:
                case 4:
                        /*
                         * There is a discrepancy here between the size reported
                         * by the register and the size of the context layout
                         * in the docs. Both are described as authorative!
                         *
                         * The discrepancy is on the order of a few cachelines,
                         * but the total is under one page (4k), which is our
                         * minimum allocation anyway so it should all come
                         * out in the wash.
                         */
                        cxt_size = intel_uncore_read(uncore, CXT_SIZE) + 1;
                        drm_dbg(&gt->i915->drm,
                                "graphics_ver = %d CXT_SIZE = %d bytes [0x%08x]\n",
                                GRAPHICS_VER(gt->i915), cxt_size * 64,
                                cxt_size - 1);
                        return round_up(cxt_size * 64, PAGE_SIZE);
                case 3:
                case 2:
                /* For the special day when i810 gets merged. */
                case 1:
                        return 0;
                }
                break;
        default:
                MISSING_CASE(class);
                fallthrough;
        case VIDEO_DECODE_CLASS:
        case VIDEO_ENHANCEMENT_CLASS:
        case COPY_ENGINE_CLASS:
                if (GRAPHICS_VER(gt->i915) < 8)
                        return 0;
                return GEN8_LR_CONTEXT_OTHER_SIZE;
        }
}

static u32 __engine_mmio_base(struct drm_i915_private *i915,
                              const struct engine_mmio_base *bases)
{
        int i;

        for (i = 0; i < MAX_MMIO_BASES; i++)
                if (GRAPHICS_VER(i915) >= bases[i].graphics_ver)
                        break;

        GEM_BUG_ON(i == MAX_MMIO_BASES);
        GEM_BUG_ON(!bases[i].base);

        return bases[i].base;
}

static void __sprint_engine_name(struct intel_engine_cs *engine)
{
        /*
         * Before we know what the uABI name for this engine will be,
         * we still would like to keep track of this engine in the debug logs.
         * We throw in a ' here as a reminder that this isn't its final name.
         */
        GEM_WARN_ON(snprintf(engine->name, sizeof(engine->name), "%s'%u",
                             intel_engine_class_repr(engine->class),
                             engine->instance) >= sizeof(engine->name));
}

void intel_engine_set_hwsp_writemask(struct intel_engine_cs *engine, u32 mask)
{
        /*
         * Though they added more rings on g4x/ilk, they did not add
         * per-engine HWSTAM until gen6.
         */
        if (GRAPHICS_VER(engine->i915) < 6 && engine->class != RENDER_CLASS)
                return;

        if (GRAPHICS_VER(engine->i915) >= 3)
                ENGINE_WRITE(engine, RING_HWSTAM, mask);
        else
                ENGINE_WRITE16(engine, RING_HWSTAM, mask);
}

static void intel_engine_sanitize_mmio(struct intel_engine_cs *engine)
{
        /* Mask off all writes into the unknown HWSP */
        intel_engine_set_hwsp_writemask(engine, ~0u);
}

static void nop_irq_handler(struct intel_engine_cs *engine, u16 iir)
{
        GEM_DEBUG_WARN_ON(iir);
}

static int intel_engine_setup(struct intel_gt *gt, enum intel_engine_id id)
{
        const struct engine_info *info = &intel_engines[id];
        struct drm_i915_private *i915 = gt->i915;
        struct intel_engine_cs *engine;
        u8 guc_class;

        BUILD_BUG_ON(MAX_ENGINE_CLASS >= BIT(GEN11_ENGINE_CLASS_WIDTH));
        BUILD_BUG_ON(MAX_ENGINE_INSTANCE >= BIT(GEN11_ENGINE_INSTANCE_WIDTH));
        BUILD_BUG_ON(I915_MAX_VCS > (MAX_ENGINE_INSTANCE + 1));
        BUILD_BUG_ON(I915_MAX_VECS > (MAX_ENGINE_INSTANCE + 1));

        if (GEM_DEBUG_WARN_ON(id >= ARRAY_SIZE(gt->engine)))
                return -EINVAL;

        if (GEM_DEBUG_WARN_ON(info->class > MAX_ENGINE_CLASS))
                return -EINVAL;

        if (GEM_DEBUG_WARN_ON(info->instance > MAX_ENGINE_INSTANCE))
                return -EINVAL;

        if (GEM_DEBUG_WARN_ON(gt->engine_class[info->class][info->instance]))
                return -EINVAL;

        engine = kzalloc(sizeof(*engine), GFP_KERNEL);
        if (!engine)
                return -ENOMEM;

        BUILD_BUG_ON(BITS_PER_TYPE(engine->mask) < I915_NUM_ENGINES);

        engine->id = id;
        engine->legacy_idx = INVALID_ENGINE;
        engine->mask = BIT(id);
        engine->i915 = i915;
        engine->gt = gt;
        engine->uncore = gt->uncore;
        guc_class = engine_class_to_guc_class(info->class);
        engine->guc_id = MAKE_GUC_ID(guc_class, info->instance);
        engine->mmio_base = __engine_mmio_base(i915, info->mmio_bases);

        engine->irq_handler = nop_irq_handler;

        engine->class = info->class;
        engine->instance = info->instance;
        __sprint_engine_name(engine);

        engine->props.heartbeat_interval_ms =
                CONFIG_DRM_I915_HEARTBEAT_INTERVAL;
        engine->props.max_busywait_duration_ns =
                CONFIG_DRM_I915_MAX_REQUEST_BUSYWAIT;
        engine->props.preempt_timeout_ms =
                CONFIG_DRM_I915_PREEMPT_TIMEOUT;
        engine->props.stop_timeout_ms =
                CONFIG_DRM_I915_STOP_TIMEOUT;
        engine->props.timeslice_duration_ms =
                CONFIG_DRM_I915_TIMESLICE_DURATION;

        /* Override to uninterruptible for OpenCL workloads. */
        if (GRAPHICS_VER(i915) == 12 && engine->class == RENDER_CLASS)
                engine->props.preempt_timeout_ms = 0;

        engine->defaults = engine->props; /* never to change again */

        engine->context_size = intel_engine_context_size(gt, engine->class);
        if (WARN_ON(engine->context_size > BIT(20)))
                engine->context_size = 0;
        if (engine->context_size)
                DRIVER_CAPS(i915)->has_logical_contexts = true;

        ewma__engine_latency_init(&engine->latency);
        seqcount_init(&engine->stats.lock);

        ATOMIC_INIT_NOTIFIER_HEAD(&engine->context_status_notifier);

        /* Scrub mmio state on takeover */
        intel_engine_sanitize_mmio(engine);

        gt->engine_class[info->class][info->instance] = engine;
        gt->engine[id] = engine;

        return 0;
}

static void __setup_engine_capabilities(struct intel_engine_cs *engine)
{
        struct drm_i915_private *i915 = engine->i915;

        if (engine->class == VIDEO_DECODE_CLASS) {
                /*
                 * HEVC support is present on first engine instance
                 * before Gen11 and on all instances afterwards.
                 */
                if (GRAPHICS_VER(i915) >= 11 ||
                    (GRAPHICS_VER(i915) >= 9 && engine->instance == 0))
                        engine->uabi_capabilities |=
                                I915_VIDEO_CLASS_CAPABILITY_HEVC;

                /*
                 * SFC block is present only on even logical engine
                 * instances.
                 */
                if ((GRAPHICS_VER(i915) >= 11 &&
                     (engine->gt->info.vdbox_sfc_access &
                      BIT(engine->instance))) ||
                    (GRAPHICS_VER(i915) >= 9 && engine->instance == 0))
                        engine->uabi_capabilities |=
                                I915_VIDEO_AND_ENHANCE_CLASS_CAPABILITY_SFC;
        } else if (engine->class == VIDEO_ENHANCEMENT_CLASS) {
                if (GRAPHICS_VER(i915) >= 9)
                        engine->uabi_capabilities |=
                                I915_VIDEO_AND_ENHANCE_CLASS_CAPABILITY_SFC;
        }
}

static void intel_setup_engine_capabilities(struct intel_gt *gt)
{
        struct intel_engine_cs *engine;
        enum intel_engine_id id;

        for_each_engine(engine, gt, id)
                __setup_engine_capabilities(engine);
}

/**
 * intel_engines_release() - free the resources allocated for Command Streamers
 * @gt: pointer to struct intel_gt
 */
void intel_engines_release(struct intel_gt *gt)
{
        struct intel_engine_cs *engine;
        enum intel_engine_id id;

        /*
         * Before we release the resources held by engine, we must be certain
         * that the HW is no longer accessing them -- having the GPU scribble
         * to or read from a page being used for something else causes no end
         * of fun.
         *
         * The GPU should be reset by this point, but assume the worst just
         * in case we aborted before completely initialising the engines.
         */
        GEM_BUG_ON(intel_gt_pm_is_awake(gt));
        if (!INTEL_INFO(gt->i915)->gpu_reset_clobbers_display)
                __intel_gt_reset(gt, ALL_ENGINES);

        /* Decouple the backend; but keep the layout for late GPU resets */
        for_each_engine(engine, gt, id) {
                if (!engine->release)
                        continue;

                intel_wakeref_wait_for_idle(&engine->wakeref);
                GEM_BUG_ON(intel_engine_pm_is_awake(engine));

                engine->release(engine);
                engine->release = NULL;

                memset(&engine->reset, 0, sizeof(engine->reset));
        }
}

void intel_engine_free_request_pool(struct intel_engine_cs *engine)
{
        if (!engine->request_pool)
                return;

        kmem_cache_free(i915_request_slab_cache(), engine->request_pool);
}

void intel_engines_free(struct intel_gt *gt)
{
        struct intel_engine_cs *engine;
        enum intel_engine_id id;

        /* Free the requests! dma-resv keeps fences around for an eternity */
        rcu_barrier();

        for_each_engine(engine, gt, id) {
                intel_engine_free_request_pool(engine);
                kfree(engine);
                gt->engine[id] = NULL;
        }
}

static
bool gen11_vdbox_has_sfc(struct drm_i915_private *i915,
                         unsigned int physical_vdbox,
                         unsigned int logical_vdbox, u16 vdbox_mask)
{
        /*
         * In Gen11, only even numbered logical VDBOXes are hooked
         * up to an SFC (Scaler & Format Converter) unit.
         * In Gen12, Even numbered physical instance always are connected
         * to an SFC. Odd numbered physical instances have SFC only if
         * previous even instance is fused off.
         */
        if (GRAPHICS_VER(i915) == 12)
                return (physical_vdbox % 2 == 0) ||
                        !(BIT(physical_vdbox - 1) & vdbox_mask);
        else if (GRAPHICS_VER(i915) == 11)
                return logical_vdbox % 2 == 0;

        MISSING_CASE(GRAPHICS_VER(i915));
        return false;
}

/*
 * Determine which engines are fused off in our particular hardware.
 * Note that we have a catch-22 situation where we need to be able to access
 * the blitter forcewake domain to read the engine fuses, but at the same time
 * we need to know which engines are available on the system to know which
 * forcewake domains are present. We solve this by intializing the forcewake
 * domains based on the full engine mask in the platform capabilities before
 * calling this function and pruning the domains for fused-off engines
 * afterwards.
 */
static intel_engine_mask_t init_engine_mask(struct intel_gt *gt)
{
        struct drm_i915_private *i915 = gt->i915;
        struct intel_gt_info *info = &gt->info;
        struct intel_uncore *uncore = gt->uncore;
        unsigned int logical_vdbox = 0;
        unsigned int i;
        u32 media_fuse;
        u16 vdbox_mask;
        u16 vebox_mask;

        info->engine_mask = INTEL_INFO(i915)->platform_engine_mask;

        if (GRAPHICS_VER(i915) < 11)
                return info->engine_mask;

        /*
         * On newer platforms the fusing register is called 'enable' and has
         * enable semantics, while on older platforms it is called 'disable'
         * and bits have disable semantices.
         */
        media_fuse = intel_uncore_read(uncore, GEN11_GT_VEBOX_VDBOX_DISABLE);
        if (GRAPHICS_VER_FULL(i915) < IP_VER(12, 50))
                media_fuse = ~media_fuse;

        vdbox_mask = media_fuse & GEN11_GT_VDBOX_DISABLE_MASK;
        vebox_mask = (media_fuse & GEN11_GT_VEBOX_DISABLE_MASK) >>
                      GEN11_GT_VEBOX_DISABLE_SHIFT;

        for (i = 0; i < I915_MAX_VCS; i++) {
                if (!HAS_ENGINE(gt, _VCS(i))) {
                        vdbox_mask &= ~BIT(i);
                        continue;
                }

                if (!(BIT(i) & vdbox_mask)) {
                        info->engine_mask &= ~BIT(_VCS(i));
                        drm_dbg(&i915->drm, "vcs%u fused off\n", i);
                        continue;
                }

                if (gen11_vdbox_has_sfc(i915, i, logical_vdbox, vdbox_mask))
                        gt->info.vdbox_sfc_access |= BIT(i);
                logical_vdbox++;
        }
        drm_dbg(&i915->drm, "vdbox enable: %04x, instances: %04lx\n",
                vdbox_mask, VDBOX_MASK(gt));
        GEM_BUG_ON(vdbox_mask != VDBOX_MASK(gt));

        for (i = 0; i < I915_MAX_VECS; i++) {
                if (!HAS_ENGINE(gt, _VECS(i))) {
                        vebox_mask &= ~BIT(i);
                        continue;
                }

                if (!(BIT(i) & vebox_mask)) {
                        info->engine_mask &= ~BIT(_VECS(i));
                        drm_dbg(&i915->drm, "vecs%u fused off\n", i);
                }
        }
        drm_dbg(&i915->drm, "vebox enable: %04x, instances: %04lx\n",
                vebox_mask, VEBOX_MASK(gt));
        GEM_BUG_ON(vebox_mask != VEBOX_MASK(gt));

        return info->engine_mask;
}

/**
 * intel_engines_init_mmio() - allocate and prepare the Engine Command Streamers
 * @gt: pointer to struct intel_gt
 *
 * Return: non-zero if the initialization failed.
 */
int intel_engines_init_mmio(struct intel_gt *gt)
{
        struct drm_i915_private *i915 = gt->i915;
        const unsigned int engine_mask = init_engine_mask(gt);
        unsigned int mask = 0;
        unsigned int i;
        int err;

        drm_WARN_ON(&i915->drm, engine_mask == 0);
        drm_WARN_ON(&i915->drm, engine_mask &
                    GENMASK(BITS_PER_TYPE(mask) - 1, I915_NUM_ENGINES));

        if (i915_inject_probe_failure(i915))
                return -ENODEV;

        for (i = 0; i < ARRAY_SIZE(intel_engines); i++) {
                if (!HAS_ENGINE(gt, i))
                        continue;

                err = intel_engine_setup(gt, i);
                if (err)
                        goto cleanup;

                mask |= BIT(i);
        }

        /*
         * Catch failures to update intel_engines table when the new engines
         * are added to the driver by a warning and disabling the forgotten
         * engines.
         */
        if (drm_WARN_ON(&i915->drm, mask != engine_mask))
                gt->info.engine_mask = mask;

        gt->info.num_engines = hweight32(mask);

        intel_gt_check_and_clear_faults(gt);

        intel_setup_engine_capabilities(gt);

        intel_uncore_prune_engine_fw_domains(gt->uncore, gt);

        return 0;

cleanup:
        intel_engines_free(gt);
        return err;
}

void intel_engine_init_execlists(struct intel_engine_cs *engine)
{
        struct intel_engine_execlists * const execlists = &engine->execlists;

        execlists->port_mask = 1;
        GEM_BUG_ON(!is_power_of_2(execlists_num_ports(execlists)));
        GEM_BUG_ON(execlists_num_ports(execlists) > EXECLIST_MAX_PORTS);

        memset(execlists->pending, 0, sizeof(execlists->pending));
        execlists->active =
                memset(execlists->inflight, 0, sizeof(execlists->inflight));
}

static void cleanup_status_page(struct intel_engine_cs *engine)
{
        struct i915_vma *vma;

        /* Prevent writes into HWSP after returning the page to the system */
        intel_engine_set_hwsp_writemask(engine, ~0u);

        vma = fetch_and_zero(&engine->status_page.vma);
        if (!vma)
                return;

        if (!HWS_NEEDS_PHYSICAL(engine->i915))
                i915_vma_unpin(vma);

        i915_gem_object_unpin_map(vma->obj);
        i915_gem_object_put(vma->obj);
}

static int pin_ggtt_status_page(struct intel_engine_cs *engine,
                                struct i915_gem_ww_ctx *ww,
                                struct i915_vma *vma)
{
        unsigned int flags;

        if (!HAS_LLC(engine->i915) && i915_ggtt_has_aperture(engine->gt->ggtt))
                /*
                 * On g33, we cannot place HWS above 256MiB, so
                 * restrict its pinning to the low mappable arena.
                 * Though this restriction is not documented for
                 * gen4, gen5, or byt, they also behave similarly
                 * and hang if the HWS is placed at the top of the
                 * GTT. To generalise, it appears that all !llc
                 * platforms have issues with us placing the HWS
                 * above the mappable region (even though we never
                 * actually map it).
                 */
                flags = PIN_MAPPABLE;
        else
                flags = PIN_HIGH;

        return i915_ggtt_pin(vma, ww, 0, flags);
}

static int init_status_page(struct intel_engine_cs *engine)
{
        struct drm_i915_gem_object *obj;
        struct i915_gem_ww_ctx ww;
        struct i915_vma *vma;
        void *vaddr;
        int ret;

        INIT_LIST_HEAD(&engine->status_page.timelines);

        /*
         * Though the HWS register does support 36bit addresses, historically
         * we have had hangs and corruption reported due to wild writes if
         * the HWS is placed above 4G. We only allow objects to be allocated
         * in GFP_DMA32 for i965, and no earlier physical address users had
         * access to more than 4G.
         */
        obj = i915_gem_object_create_internal(engine->i915, PAGE_SIZE);
        if (IS_ERR(obj)) {
                drm_err(&engine->i915->drm,
                        "Failed to allocate status page\n");
                return PTR_ERR(obj);
        }

        i915_gem_object_set_cache_coherency(obj, I915_CACHE_LLC);

        vma = i915_vma_instance(obj, &engine->gt->ggtt->vm, NULL);
        if (IS_ERR(vma)) {
                ret = PTR_ERR(vma);
                goto err_put;
        }

        i915_gem_ww_ctx_init(&ww, true);
retry:
        ret = i915_gem_object_lock(obj, &ww);
        if (!ret && !HWS_NEEDS_PHYSICAL(engine->i915))
                ret = pin_ggtt_status_page(engine, &ww, vma);
        if (ret)
                goto err;

        vaddr = i915_gem_object_pin_map(obj, I915_MAP_WB);
        if (IS_ERR(vaddr)) {
                ret = PTR_ERR(vaddr);
                goto err_unpin;
        }

        engine->status_page.addr = memset(vaddr, 0, PAGE_SIZE);
        engine->status_page.vma = vma;

err_unpin:
        if (ret)
                i915_vma_unpin(vma);
err:
        if (ret == -EDEADLK) {
                ret = i915_gem_ww_ctx_backoff(&ww);
                if (!ret)
                        goto retry;
        }
        i915_gem_ww_ctx_fini(&ww);
err_put:
        if (ret)
                i915_gem_object_put(obj);
        return ret;
}

static int engine_setup_common(struct intel_engine_cs *engine)
{
        int err;

        init_llist_head(&engine->barrier_tasks);

        err = init_status_page(engine);
        if (err)
                return err;

        engine->breadcrumbs = intel_breadcrumbs_create(engine);
        if (!engine->breadcrumbs) {
                err = -ENOMEM;
                goto err_status;
        }

        engine->sched_engine = i915_sched_engine_create(ENGINE_PHYSICAL);
        if (!engine->sched_engine) {
                err = -ENOMEM;
                goto err_sched_engine;
        }
        engine->sched_engine->private_data = engine;

        err = intel_engine_init_cmd_parser(engine);
        if (err)
                goto err_cmd_parser;

        intel_engine_init_execlists(engine);
        intel_engine_init__pm(engine);
        intel_engine_init_retire(engine);

        /* Use the whole device by default */
        engine->sseu =
                intel_sseu_from_device_info(&engine->gt->info.sseu);

        intel_engine_init_workarounds(engine);
        intel_engine_init_whitelist(engine);
        intel_engine_init_ctx_wa(engine);

        if (GRAPHICS_VER(engine->i915) >= 12)
                engine->flags |= I915_ENGINE_HAS_RELATIVE_MMIO;

        return 0;

err_cmd_parser:
        i915_sched_engine_put(engine->sched_engine);
err_sched_engine:
        intel_breadcrumbs_put(engine->breadcrumbs);
err_status:
        cleanup_status_page(engine);
        return err;
}

struct measure_breadcrumb {
        struct i915_request rq;
        struct intel_ring ring;
        u32 cs[2048];
};

static int measure_breadcrumb_dw(struct intel_context *ce)
{
        struct intel_engine_cs *engine = ce->engine;
        struct measure_breadcrumb *frame;
        int dw;

        GEM_BUG_ON(!engine->gt->scratch);

        frame = kzalloc(sizeof(*frame), GFP_KERNEL);
        if (!frame)
                return -ENOMEM;

        frame->rq.engine = engine;
        frame->rq.context = ce;
        rcu_assign_pointer(frame->rq.timeline, ce->timeline);
        frame->rq.hwsp_seqno = ce->timeline->hwsp_seqno;

        frame->ring.vaddr = frame->cs;
        frame->ring.size = sizeof(frame->cs);
        frame->ring.wrap =
                BITS_PER_TYPE(frame->ring.size) - ilog2(frame->ring.size);
        frame->ring.effective_size = frame->ring.size;
        intel_ring_update_space(&frame->ring);
        frame->rq.ring = &frame->ring;

        mutex_lock(&ce->timeline->mutex);
        spin_lock_irq(&engine->sched_engine->lock);

        dw = engine->emit_fini_breadcrumb(&frame->rq, frame->cs) - frame->cs;

        spin_unlock_irq(&engine->sched_engine->lock);
        mutex_unlock(&ce->timeline->mutex);

        GEM_BUG_ON(dw & 1); /* RING_TAIL must be qword aligned */

        kfree(frame);
        return dw;
}

struct intel_context *
intel_engine_create_pinned_context(struct intel_engine_cs *engine,
                                   struct i915_address_space *vm,
                                   unsigned int ring_size,
                                   unsigned int hwsp,
                                   struct lock_class_key *key,
                                   const char *name)
{
        struct intel_context *ce;
        int err;

        ce = intel_context_create(engine);
        if (IS_ERR(ce))
                return ce;

        __set_bit(CONTEXT_BARRIER_BIT, &ce->flags);
        ce->timeline = page_pack_bits(NULL, hwsp);
        ce->ring = NULL;
        ce->ring_size = ring_size;

        i915_vm_put(ce->vm);
        ce->vm = i915_vm_get(vm);

        err = intel_context_pin(ce); /* perma-pin so it is always available */
        if (err) {
                intel_context_put(ce);
                return ERR_PTR(err);
        }

        /*
         * Give our perma-pinned kernel timelines a separate lockdep class,
         * so that we can use them from within the normal user timelines
         * should we need to inject GPU operations during their request
         * construction.
         */
        lockdep_set_class_and_name(&ce->timeline->mutex, key, name);

        return ce;
}

void intel_engine_destroy_pinned_context(struct intel_context *ce)
{
        struct intel_engine_cs *engine = ce->engine;
        struct i915_vma *hwsp = engine->status_page.vma;

        GEM_BUG_ON(ce->timeline->hwsp_ggtt != hwsp);

        mutex_lock(&hwsp->vm->mutex);
        list_del(&ce->timeline->engine_link);
        mutex_unlock(&hwsp->vm->mutex);

        intel_context_unpin(ce);
        intel_context_put(ce);
}

static struct intel_context *
create_kernel_context(struct intel_engine_cs *engine)
{
        static struct lock_class_key kernel;

        return intel_engine_create_pinned_context(engine, engine->gt->vm, SZ_4K,
                                                  I915_GEM_HWS_SEQNO_ADDR,
                                                  &kernel, "kernel_context");
}

/**
 * intel_engines_init_common - initialize cengine state which might require hw access
 * @engine: Engine to initialize.
 *
 * Initializes @engine@ structure members shared between legacy and execlists
 * submission modes which do require hardware access.
 *
 * Typcally done at later stages of submission mode specific engine setup.
 *
 * Returns zero on success or an error code on failure.
 */
static int engine_init_common(struct intel_engine_cs *engine)
{
        struct intel_context *ce;
        int ret;

        engine->set_default_submission(engine);

        /*
         * We may need to do things with the shrinker which
         * require us to immediately switch back to the default
         * context. This can cause a problem as pinning the
         * default context also requires GTT space which may not
         * be available. To avoid this we always pin the default
         * context.
         */
        ce = create_kernel_context(engine);
        if (IS_ERR(ce))
                return PTR_ERR(ce);

        ret = measure_breadcrumb_dw(ce);
        if (ret < 0)
                goto err_context;

        engine->emit_fini_breadcrumb_dw = ret;
        engine->kernel_context = ce;

        return 0;

err_context:
        intel_engine_destroy_pinned_context(ce);
        return ret;
}

int intel_engines_init(struct intel_gt *gt)
{
        int (*setup)(struct intel_engine_cs *engine);
        struct intel_engine_cs *engine;
        enum intel_engine_id id;
        int err;

        if (intel_uc_uses_guc_submission(&gt->uc)) {
                gt->submission_method = INTEL_SUBMISSION_GUC;
                setup = intel_guc_submission_setup;
        } else if (HAS_EXECLISTS(gt->i915)) {
                gt->submission_method = INTEL_SUBMISSION_ELSP;
                setup = intel_execlists_submission_setup;
        } else {
                gt->submission_method = INTEL_SUBMISSION_RING;
                setup = intel_ring_submission_setup;
        }

        for_each_engine(engine, gt, id) {
                err = engine_setup_common(engine);
                if (err)
                        return err;

                err = setup(engine);
                if (err)
                        return err;

                err = engine_init_common(engine);
                if (err)
                        return err;

                intel_engine_add_user(engine);
        }

        return 0;
}

/**
 * intel_engines_cleanup_common - cleans up the engine state created by
 *                                the common initiailizers.
 * @engine: Engine to cleanup.
 *
 * This cleans up everything created by the common helpers.

 */
void intel_engine_cleanup_common(struct intel_engine_cs *engine)
{
        GEM_BUG_ON(!list_empty(&engine->sched_engine->requests));

        i915_sched_engine_put(engine->sched_engine);
        intel_breadcrumbs_put(engine->breadcrumbs);

        intel_engine_fini_retire(engine);
        intel_engine_cleanup_cmd_parser(engine);

        if (engine->default_state)
                fput(engine->default_state);

        if (engine->kernel_context)
                intel_engine_destroy_pinned_context(engine->kernel_context);

        GEM_BUG_ON(!llist_empty(&engine->barrier_tasks));
        cleanup_status_page(engine);

        intel_wa_list_free(&engine->ctx_wa_list);
        intel_wa_list_free(&engine->wa_list);
        intel_wa_list_free(&engine->whitelist);
}

/**
 * intel_engine_resume - re-initializes the HW state of the engine
 * @engine: Engine to resume.
 *
 * Returns zero on success or an error code on failure.
 */
int intel_engine_resume(struct intel_engine_cs *engine)
{
        intel_engine_apply_workarounds(engine);
        intel_engine_apply_whitelist(engine);

        return engine->resume(engine);
}

u64 intel_engine_get_active_head(const struct intel_engine_cs *engine)
{
        struct drm_i915_private *i915 = engine->i915;

        u64 acthd;

        if (GRAPHICS_VER(i915) >= 8)
                acthd = ENGINE_READ64(engine, RING_ACTHD, RING_ACTHD_UDW);
        else if (GRAPHICS_VER(i915) >= 4)
                acthd = ENGINE_READ(engine, RING_ACTHD);
        else
                acthd = ENGINE_READ(engine, ACTHD);

        return acthd;
}

u64 intel_engine_get_last_batch_head(const struct intel_engine_cs *engine)
{
        u64 bbaddr;

        if (GRAPHICS_VER(engine->i915) >= 8)
                bbaddr = ENGINE_READ64(engine, RING_BBADDR, RING_BBADDR_UDW);
        else
                bbaddr = ENGINE_READ(engine, RING_BBADDR);

        return bbaddr;
}

static unsigned long stop_timeout(const struct intel_engine_cs *engine)
{
        if (in_atomic() || irqs_disabled()) /* inside atomic preempt-reset? */
                return 0;

        /*
         * If we are doing a normal GPU reset, we can take our time and allow
         * the engine to quiesce. We've stopped submission to the engine, and
         * if we wait long enough an innocent context should complete and
         * leave the engine idle. So they should not be caught unaware by
         * the forthcoming GPU reset (which usually follows the stop_cs)!
         */
        return READ_ONCE(engine->props.stop_timeout_ms);
}

static int __intel_engine_stop_cs(struct intel_engine_cs *engine,
                                  int fast_timeout_us,
                                  int slow_timeout_ms)
{
        struct intel_uncore *uncore = engine->uncore;
        const i915_reg_t mode = RING_MI_MODE(engine->mmio_base);
        int err;

        intel_uncore_write_fw(uncore, mode, _MASKED_BIT_ENABLE(STOP_RING));
        err = __intel_wait_for_register_fw(engine->uncore, mode,
                                           MODE_IDLE, MODE_IDLE,
                                           fast_timeout_us,
                                           slow_timeout_ms,
                                           NULL);

        /* A final mmio read to let GPU writes be hopefully flushed to memory */
        intel_uncore_posting_read_fw(uncore, mode);
        return err;
}

int intel_engine_stop_cs(struct intel_engine_cs *engine)
{
        int err = 0;

        if (GRAPHICS_VER(engine->i915) < 3)
                return -ENODEV;

        ENGINE_TRACE(engine, "\n");
        if (__intel_engine_stop_cs(engine, 1000, stop_timeout(engine))) {
                ENGINE_TRACE(engine,
                             "timed out on STOP_RING -> IDLE; HEAD:%04x, TAIL:%04x\n",
                             ENGINE_READ_FW(engine, RING_HEAD) & HEAD_ADDR,
                             ENGINE_READ_FW(engine, RING_TAIL) & TAIL_ADDR);

                /*
                 * Sometimes we observe that the idle flag is not
                 * set even though the ring is empty. So double
                 * check before giving up.
                 */
                if ((ENGINE_READ_FW(engine, RING_HEAD) & HEAD_ADDR) !=
                    (ENGINE_READ_FW(engine, RING_TAIL) & TAIL_ADDR))
                        err = -ETIMEDOUT;
        }

        return err;
}

void intel_engine_cancel_stop_cs(struct intel_engine_cs *engine)
{
        ENGINE_TRACE(engine, "\n");

        ENGINE_WRITE_FW(engine, RING_MI_MODE, _MASKED_BIT_DISABLE(STOP_RING));
}

const char *i915_cache_level_str(struct drm_i915_private *i915, int type)
{
        switch (type) {
        case I915_CACHE_NONE: return " uncached";
        case I915_CACHE_LLC: return HAS_LLC(i915) ? " LLC" : " snooped";
        case I915_CACHE_L3_LLC: return " L3+LLC";
        case I915_CACHE_WT: return " WT";
        default: return "";
        }
}

static u32
read_subslice_reg(const struct intel_engine_cs *engine,
                  int slice, int subslice, i915_reg_t reg)
{
        return intel_uncore_read_with_mcr_steering(engine->uncore, reg,
                                                   slice, subslice);
}

/* NB: please notice the memset */
void intel_engine_get_instdone(const struct intel_engine_cs *engine,
                               struct intel_instdone *instdone)
{
        struct drm_i915_private *i915 = engine->i915;
        const struct sseu_dev_info *sseu = &engine->gt->info.sseu;
        struct intel_uncore *uncore = engine->uncore;
        u32 mmio_base = engine->mmio_base;
        int slice;
        int subslice;

        memset(instdone, 0, sizeof(*instdone));

        switch (GRAPHICS_VER(i915)) {
        default:
                instdone->instdone =
                        intel_uncore_read(uncore, RING_INSTDONE(mmio_base));

                if (engine->id != RCS0)
                        break;

                instdone->slice_common =
                        intel_uncore_read(uncore, GEN7_SC_INSTDONE);
                if (GRAPHICS_VER(i915) >= 12) {
                        instdone->slice_common_extra[0] =
                                intel_uncore_read(uncore, GEN12_SC_INSTDONE_EXTRA);
                        instdone->slice_common_extra[1] =
                                intel_uncore_read(uncore, GEN12_SC_INSTDONE_EXTRA2);
                }
                for_each_instdone_slice_subslice(i915, sseu, slice, subslice) {
                        instdone->sampler[slice][subslice] =
                                read_subslice_reg(engine, slice, subslice,
                                                  GEN7_SAMPLER_INSTDONE);
                        instdone->row[slice][subslice] =
                                read_subslice_reg(engine, slice, subslice,
                                                  GEN7_ROW_INSTDONE);
                }
                break;
        case 7:
                instdone->instdone =
                        intel_uncore_read(uncore, RING_INSTDONE(mmio_base));

                if (engine->id != RCS0)
                        break;

                instdone->slice_common =
                        intel_uncore_read(uncore, GEN7_SC_INSTDONE);
                instdone->sampler[0][0] =
                        intel_uncore_read(uncore, GEN7_SAMPLER_INSTDONE);
                instdone->row[0][0] =
                        intel_uncore_read(uncore, GEN7_ROW_INSTDONE);

                break;
        case 6:
        case 5:
        case 4:
                instdone->instdone =
                        intel_uncore_read(uncore, RING_INSTDONE(mmio_base));
                if (engine->id == RCS0)
                        /* HACK: Using the wrong struct member */
                        instdone->slice_common =
                                intel_uncore_read(uncore, GEN4_INSTDONE1);
                break;
        case 3:
        case 2:
                instdone->instdone = intel_uncore_read(uncore, GEN2_INSTDONE);
                break;
        }
}

static bool ring_is_idle(struct intel_engine_cs *engine)
{
        bool idle = true;

        if (I915_SELFTEST_ONLY(!engine->mmio_base))
                return true;

        if (!intel_engine_pm_get_if_awake(engine))
                return true;

        /* First check that no commands are left in the ring */
        if ((ENGINE_READ(engine, RING_HEAD) & HEAD_ADDR) !=
            (ENGINE_READ(engine, RING_TAIL) & TAIL_ADDR))
                idle = false;

        /* No bit for gen2, so assume the CS parser is idle */
        if (GRAPHICS_VER(engine->i915) > 2 &&
            !(ENGINE_READ(engine, RING_MI_MODE) & MODE_IDLE))
                idle = false;

        intel_engine_pm_put(engine);

        return idle;
}

void __intel_engine_flush_submission(struct intel_engine_cs *engine, bool sync)
{
        struct tasklet_struct *t = &engine->sched_engine->tasklet;

        if (!t->callback)
                return;

        local_bh_disable();
        if (tasklet_trylock(t)) {
                /* Must wait for any GPU reset in progress. */
                if (__tasklet_is_enabled(t))
                        t->callback(t);
                tasklet_unlock(t);
        }
        local_bh_enable();

        /* Synchronise and wait for the tasklet on another CPU */
        if (sync)
                tasklet_unlock_wait(t);
}

/**
 * intel_engine_is_idle() - Report if the engine has finished process all work
 * @engine: the intel_engine_cs
 *
 * Return true if there are no requests pending, nothing left to be submitted
 * to hardware, and that the engine is idle.
 */
bool intel_engine_is_idle(struct intel_engine_cs *engine)
{
        /* More white lies, if wedged, hw state is inconsistent */
        if (intel_gt_is_wedged(engine->gt))
                return true;

        if (!intel_engine_pm_is_awake(engine))
                return true;

        /* Waiting to drain ELSP? */
        intel_synchronize_hardirq(engine->i915);
        intel_engine_flush_submission(engine);

        /* ELSP is empty, but there are ready requests? E.g. after reset */
        if (!i915_sched_engine_is_empty(engine->sched_engine))
                return false;

        /* Ring stopped? */
        return ring_is_idle(engine);
}

bool intel_engines_are_idle(struct intel_gt *gt)
{
        struct intel_engine_cs *engine;
        enum intel_engine_id id;

        /*
         * If the driver is wedged, HW state may be very inconsistent and
         * report that it is still busy, even though we have stopped using it.
         */
        if (intel_gt_is_wedged(gt))
                return true;

        /* Already parked (and passed an idleness test); must still be idle */
        if (!READ_ONCE(gt->awake))
                return true;

        for_each_engine(engine, gt, id) {
                if (!intel_engine_is_idle(engine))
                        return false;
        }

        return true;
}

bool intel_engine_irq_enable(struct intel_engine_cs *engine)
{
        if (!engine->irq_enable)
                return false;

        /* Caller disables interrupts */
        spin_lock(&engine->gt->irq_lock);
        engine->irq_enable(engine);
        spin_unlock(&engine->gt->irq_lock);

        return true;
}

void intel_engine_irq_disable(struct intel_engine_cs *engine)
{
        if (!engine->irq_disable)
                return;

        /* Caller disables interrupts */
        spin_lock(&engine->gt->irq_lock);
        engine->irq_disable(engine);
        spin_unlock(&engine->gt->irq_lock);
}

void intel_engines_reset_default_submission(struct intel_gt *gt)
{
        struct intel_engine_cs *engine;
        enum intel_engine_id id;

        for_each_engine(engine, gt, id) {
                if (engine->sanitize)
                        engine->sanitize(engine);

                engine->set_default_submission(engine);
        }
}

bool intel_engine_can_store_dword(struct intel_engine_cs *engine)
{
        switch (GRAPHICS_VER(engine->i915)) {
        case 2:
                return false; /* uses physical not virtual addresses */
        case 3:
                /* maybe only uses physical not virtual addresses */
                return !(IS_I915G(engine->i915) || IS_I915GM(engine->i915));
        case 4:
                return !IS_I965G(engine->i915); /* who knows! */
        case 6:
                return engine->class != VIDEO_DECODE_CLASS; /* b0rked */
        default:
                return true;
        }
}

static struct intel_timeline *get_timeline(struct i915_request *rq)
{
        struct intel_timeline *tl;

        /*
         * Even though we are holding the engine->sched_engine->lock here, there
         * is no control over the submission queue per-se and we are
         * inspecting the active state at a random point in time, with an
         * unknown queue. Play safe and make sure the timeline remains valid.
         * (Only being used for pretty printing, one extra kref shouldn't
         * cause a camel stampede!)
         */
        rcu_read_lock();
        tl = rcu_dereference(rq->timeline);
        if (!kref_get_unless_zero(&tl->kref))
                tl = NULL;
        rcu_read_unlock();

        return tl;
}

static int print_ring(char *buf, int sz, struct i915_request *rq)
{
        int len = 0;

        if (!i915_request_signaled(rq)) {
                struct intel_timeline *tl = get_timeline(rq);

                len = scnprintf(buf, sz,
                                "ring:{start:%08x, hwsp:%08x, seqno:%08x, runtime:%llums}, ",
                                i915_ggtt_offset(rq->ring->vma),
                                tl ? tl->hwsp_offset : 0,
                                hwsp_seqno(rq),
                                DIV_ROUND_CLOSEST_ULL(intel_context_get_total_runtime_ns(rq->context),
                                                      1000 * 1000));

                if (tl)
                        intel_timeline_put(tl);
        }

        return len;
}

static void hexdump(struct drm_printer *m, const void *buf, size_t len)
{
        const size_t rowsize = 8 * sizeof(u32);
        const void *prev = NULL;
        bool skip = false;
        size_t pos;

        for (pos = 0; pos < len; pos += rowsize) {
                char line[128];

                if (prev && !memcmp(prev, buf + pos, rowsize)) {
                        if (!skip) {
                                drm_printf(m, "*\n");
                                skip = true;
                        }
                        continue;
                }

                WARN_ON_ONCE(hex_dump_to_buffer(buf + pos, len - pos,
                                                rowsize, sizeof(u32),
                                                line, sizeof(line),
                                                false) >= sizeof(line));
                drm_printf(m, "[%04zx] %s\n", pos, line);

                prev = buf + pos;
                skip = false;
        }
}

static const char *repr_timer(const struct timer_list *t)
{
        if (!READ_ONCE(t->expires))
                return "inactive";

        if (timer_pending(t))
                return "active";

        return "expired";
}

static void intel_engine_print_registers(struct intel_engine_cs *engine,
                                         struct drm_printer *m)
{
        struct drm_i915_private *dev_priv = engine->i915;
        struct intel_engine_execlists * const execlists = &engine->execlists;
        u64 addr;

        if (engine->id == RENDER_CLASS && IS_GRAPHICS_VER(dev_priv, 4, 7))
                drm_printf(m, "\tCCID: 0x%08x\n", ENGINE_READ(engine, CCID));
        if (HAS_EXECLISTS(dev_priv)) {
                drm_printf(m, "\tEL_STAT_HI: 0x%08x\n",
                           ENGINE_READ(engine, RING_EXECLIST_STATUS_HI));
                drm_printf(m, "\tEL_STAT_LO: 0x%08x\n",
                           ENGINE_READ(engine, RING_EXECLIST_STATUS_LO));
        }
        drm_printf(m, "\tRING_START: 0x%08x\n",
                   ENGINE_READ(engine, RING_START));
        drm_printf(m, "\tRING_HEAD:  0x%08x\n",
                   ENGINE_READ(engine, RING_HEAD) & HEAD_ADDR);
        drm_printf(m, "\tRING_TAIL:  0x%08x\n",
                   ENGINE_READ(engine, RING_TAIL) & TAIL_ADDR);
        drm_printf(m, "\tRING_CTL:   0x%08x%s\n",
                   ENGINE_READ(engine, RING_CTL),
                   ENGINE_READ(engine, RING_CTL) & (RING_WAIT | RING_WAIT_SEMAPHORE) ? " [waiting]" : "");
        if (GRAPHICS_VER(engine->i915) > 2) {
                drm_printf(m, "\tRING_MODE:  0x%08x%s\n",
                           ENGINE_READ(engine, RING_MI_MODE),
                           ENGINE_READ(engine, RING_MI_MODE) & (MODE_IDLE) ? " [idle]" : "");
        }

        if (GRAPHICS_VER(dev_priv) >= 6) {
                drm_printf(m, "\tRING_IMR:   0x%08x\n",
                           ENGINE_READ(engine, RING_IMR));
                drm_printf(m, "\tRING_ESR:   0x%08x\n",
                           ENGINE_READ(engine, RING_ESR));
                drm_printf(m, "\tRING_EMR:   0x%08x\n",
                           ENGINE_READ(engine, RING_EMR));
                drm_printf(m, "\tRING_EIR:   0x%08x\n",
                           ENGINE_READ(engine, RING_EIR));
        }

        addr = intel_engine_get_active_head(engine);
        drm_printf(m, "\tACTHD:  0x%08x_%08x\n",
                   upper_32_bits(addr), lower_32_bits(addr));
        addr = intel_engine_get_last_batch_head(engine);
        drm_printf(m, "\tBBADDR: 0x%08x_%08x\n",
                   upper_32_bits(addr), lower_32_bits(addr));
        if (GRAPHICS_VER(dev_priv) >= 8)
                addr = ENGINE_READ64(engine, RING_DMA_FADD, RING_DMA_FADD_UDW);
        else if (GRAPHICS_VER(dev_priv) >= 4)
                addr = ENGINE_READ(engine, RING_DMA_FADD);
        else
                addr = ENGINE_READ(engine, DMA_FADD_I8XX);
        drm_printf(m, "\tDMA_FADDR: 0x%08x_%08x\n",
                   upper_32_bits(addr), lower_32_bits(addr));
        if (GRAPHICS_VER(dev_priv) >= 4) {
                drm_printf(m, "\tIPEIR: 0x%08x\n",
                           ENGINE_READ(engine, RING_IPEIR));
                drm_printf(m, "\tIPEHR: 0x%08x\n",
                           ENGINE_READ(engine, RING_IPEHR));
        } else {
                drm_printf(m, "\tIPEIR: 0x%08x\n", ENGINE_READ(engine, IPEIR));
                drm_printf(m, "\tIPEHR: 0x%08x\n", ENGINE_READ(engine, IPEHR));
        }

        if (intel_engine_uses_guc(engine)) {
                /* nothing to print yet */
        } else if (HAS_EXECLISTS(dev_priv)) {
                struct i915_request * const *port, *rq;
                const u32 *hws =
                        &engine->status_page.addr[I915_HWS_CSB_BUF0_INDEX];
                const u8 num_entries = execlists->csb_size;
                unsigned int idx;
                u8 read, write;

                drm_printf(m, "\tExeclist tasklet queued? %s (%s), preempt? %s, timeslice? %s\n",
                           yesno(test_bit(TASKLET_STATE_SCHED,
                                          &engine->sched_engine->tasklet.state)),
                           enableddisabled(!atomic_read(&engine->sched_engine->tasklet.count)),
                           repr_timer(&engine->execlists.preempt),
                           repr_timer(&engine->execlists.timer));

                read = execlists->csb_head;
                write = READ_ONCE(*execlists->csb_write);

                drm_printf(m, "\tExeclist status: 0x%08x %08x; CSB read:%d, write:%d, entries:%d\n",
                           ENGINE_READ(engine, RING_EXECLIST_STATUS_LO),
                           ENGINE_READ(engine, RING_EXECLIST_STATUS_HI),
                           read, write, num_entries);

                if (read >= num_entries)
                        read = 0;
                if (write >= num_entries)
                        write = 0;
                if (read > write)
                        write += num_entries;
                while (read < write) {
                        idx = ++read % num_entries;
                        drm_printf(m, "\tExeclist CSB[%d]: 0x%08x, context: %d\n",
                                   idx, hws[idx * 2], hws[idx * 2 + 1]);
                }

                i915_sched_engine_active_lock_bh(engine->sched_engine);
                rcu_read_lock();
                for (port = execlists->active; (rq = *port); port++) {
                        char hdr[160];
                        int len;

                        len = scnprintf(hdr, sizeof(hdr),
                                        "\t\tActive[%d]:  ccid:%08x%s%s, ",
                                        (int)(port - execlists->active),
                                        rq->context->lrc.ccid,
                                        intel_context_is_closed(rq->context) ? "!" : "",
                                        intel_context_is_banned(rq->context) ? "*" : "");
                        len += print_ring(hdr + len, sizeof(hdr) - len, rq);
                        scnprintf(hdr + len, sizeof(hdr) - len, "rq: ");
                        i915_request_show(m, rq, hdr, 0);
                }
                for (port = execlists->pending; (rq = *port); port++) {
                        char hdr[160];
                        int len;

                        len = scnprintf(hdr, sizeof(hdr),
                                        "\t\tPending[%d]: ccid:%08x%s%s, ",
                                        (int)(port - execlists->pending),
                                        rq->context->lrc.ccid,
                                        intel_context_is_closed(rq->context) ? "!" : "",
                                        intel_context_is_banned(rq->context) ? "*" : "");
                        len += print_ring(hdr + len, sizeof(hdr) - len, rq);
                        scnprintf(hdr + len, sizeof(hdr) - len, "rq: ");
                        i915_request_show(m, rq, hdr, 0);
                }
                rcu_read_unlock();
                i915_sched_engine_active_unlock_bh(engine->sched_engine);
        } else if (GRAPHICS_VER(dev_priv) > 6) {
                drm_printf(m, "\tPP_DIR_BASE: 0x%08x\n",
                           ENGINE_READ(engine, RING_PP_DIR_BASE));
                drm_printf(m, "\tPP_DIR_BASE_READ: 0x%08x\n",
                           ENGINE_READ(engine, RING_PP_DIR_BASE_READ));
                drm_printf(m, "\tPP_DIR_DCLV: 0x%08x\n",
                           ENGINE_READ(engine, RING_PP_DIR_DCLV));
        }
}

static void print_request_ring(struct drm_printer *m, struct i915_request *rq)
{
        void *ring;
        int size;

        drm_printf(m,
                   "[head %04x, postfix %04x, tail %04x, batch 0x%08x_%08x]:\n",
                   rq->head, rq->postfix, rq->tail,
                   rq->batch ? upper_32_bits(rq->batch->node.start) : ~0u,
                   rq->batch ? lower_32_bits(rq->batch->node.start) : ~0u);

        size = rq->tail - rq->head;
        if (rq->tail < rq->head)
                size += rq->ring->size;

        ring = kmalloc(size, GFP_ATOMIC);
        if (ring) {
                const void *vaddr = rq->ring->vaddr;
                unsigned int head = rq->head;
                unsigned int len = 0;

                if (rq->tail < head) {
                        len = rq->ring->size - head;
                        memcpy(ring, vaddr + head, len);
                        head = 0;
                }
                memcpy(ring + len, vaddr + head, size - len);

                hexdump(m, ring, size);
                kfree(ring);
        }
}

static unsigned long list_count(struct list_head *list)
{
        struct list_head *pos;
        unsigned long count = 0;

        list_for_each(pos, list)
                count++;

        return count;
}

static unsigned long read_ul(void *p, size_t x)
{
        return *(unsigned long *)(p + x);
}

static void print_properties(struct intel_engine_cs *engine,
                             struct drm_printer *m)
{
        static const struct pmap {
                size_t offset;
                const char *name;
        } props[] = {
#define P(x) { \
        .offset = offsetof(typeof(engine->props), x), \
        .name = #x \
}
                P(heartbeat_interval_ms),
                P(max_busywait_duration_ns),
                P(preempt_timeout_ms),
                P(stop_timeout_ms),
                P(timeslice_duration_ms),

                {},
#undef P
        };
        const struct pmap *p;

        drm_printf(m, "\tProperties:\n");
        for (p = props; p->name; p++)
                drm_printf(m, "\t\t%s: %lu [default %lu]\n",
                           p->name,
                           read_ul(&engine->props, p->offset),
                           read_ul(&engine->defaults, p->offset));
}

static void engine_dump_request(struct i915_request *rq, struct drm_printer *m, const char *msg)
{
        struct intel_timeline *tl = get_timeline(rq);

        i915_request_show(m, rq, msg, 0);

        drm_printf(m, "\t\tring->start:  0x%08x\n",
                   i915_ggtt_offset(rq->ring->vma));
        drm_printf(m, "\t\tring->head:   0x%08x\n",
                   rq->ring->head);
        drm_printf(m, "\t\tring->tail:   0x%08x\n",
                   rq->ring->tail);
        drm_printf(m, "\t\tring->emit:   0x%08x\n",
                   rq->ring->emit);
        drm_printf(m, "\t\tring->space:  0x%08x\n",
                   rq->ring->space);

        if (tl) {
                drm_printf(m, "\t\tring->hwsp:   0x%08x\n",
                           tl->hwsp_offset);
                intel_timeline_put(tl);
        }

        print_request_ring(m, rq);

        if (rq->context->lrc_reg_state) {
                drm_printf(m, "Logical Ring Context:\n");
                hexdump(m, rq->context->lrc_reg_state, PAGE_SIZE);
        }
}

void intel_engine_dump_active_requests(struct list_head *requests,
                                       struct i915_request *hung_rq,
                                       struct drm_printer *m)
{
        struct i915_request *rq;
        const char *msg;
        enum i915_request_state state;

        list_for_each_entry(rq, requests, sched.link) {
                if (rq == hung_rq)
                        continue;

                state = i915_test_request_state(rq);
                if (state < I915_REQUEST_QUEUED)
                        continue;

                if (state == I915_REQUEST_ACTIVE)
                        msg = "\t\tactive on engine";
                else
                        msg = "\t\tactive in queue";

                engine_dump_request(rq, m, msg);
        }
}

static void engine_dump_active_requests(struct intel_engine_cs *engine, struct drm_printer *m)
{
        struct i915_request *hung_rq = NULL;
        struct intel_context *ce;
        bool guc;

        /*
         * No need for an engine->irq_seqno_barrier() before the seqno reads.
         * The GPU is still running so requests are still executing and any
         * hardware reads will be out of date by the time they are reported.
         * But the intention here is just to report an instantaneous snapshot
         * so that's fine.
         */
        lockdep_assert_held(&engine->sched_engine->lock);

        drm_printf(m, "\tRequests:\n");

        guc = intel_uc_uses_guc_submission(&engine->gt->uc);
        if (guc) {
                ce = intel_engine_get_hung_context(engine);
                if (ce)
                        hung_rq = intel_context_find_active_request(ce);
        } else {
                hung_rq = intel_engine_execlist_find_hung_request(engine);
        }

        if (hung_rq)
                engine_dump_request(hung_rq, m, "\t\thung");

        if (guc)
                intel_guc_dump_active_requests(engine, hung_rq, m);
        else
                intel_engine_dump_active_requests(&engine->sched_engine->requests,
                                                  hung_rq, m);
}

void intel_engine_dump(struct intel_engine_cs *engine,
                       struct drm_printer *m,
                       const char *header, ...)
{
        struct i915_gpu_error * const error = &engine->i915->gpu_error;
        struct i915_request *rq;
        intel_wakeref_t wakeref;
        unsigned long flags;
        ktime_t dummy;

        if (header) {
                va_list ap;

                va_start(ap, header);
                drm_vprintf(m, header, &ap);
                va_end(ap);
        }

        if (intel_gt_is_wedged(engine->gt))
                drm_printf(m, "*** WEDGED ***\n");

        drm_printf(m, "\tAwake? %d\n", atomic_read(&engine->wakeref.count));
        drm_printf(m, "\tBarriers?: %s\n",
                   yesno(!llist_empty(&engine->barrier_tasks)));
        drm_printf(m, "\tLatency: %luus\n",
                   ewma__engine_latency_read(&engine->latency));
        if (intel_engine_supports_stats(engine))
                drm_printf(m, "\tRuntime: %llums\n",
                           ktime_to_ms(intel_engine_get_busy_time(engine,
                                                                  &dummy)));
        drm_printf(m, "\tForcewake: %x domains, %d active\n",
                   engine->fw_domain, READ_ONCE(engine->fw_active));

        rcu_read_lock();
        rq = READ_ONCE(engine->heartbeat.systole);
        if (rq)
                drm_printf(m, "\tHeartbeat: %d ms ago\n",
                           jiffies_to_msecs(jiffies - rq->emitted_jiffies));
        rcu_read_unlock();
        drm_printf(m, "\tReset count: %d (global %d)\n",
                   i915_reset_engine_count(error, engine),
                   i915_reset_count(error));
        print_properties(engine, m);

        spin_lock_irqsave(&engine->sched_engine->lock, flags);
        engine_dump_active_requests(engine, m);

        drm_printf(m, "\tOn hold?: %lu\n",
                   list_count(&engine->sched_engine->hold));
        spin_unlock_irqrestore(&engine->sched_engine->lock, flags);

        drm_printf(m, "\tMMIO base:  0x%08x\n", engine->mmio_base);
        wakeref = intel_runtime_pm_get_if_in_use(engine->uncore->rpm);
        if (wakeref) {
                intel_engine_print_registers(engine, m);
                intel_runtime_pm_put(engine->uncore->rpm, wakeref);
        } else {
                drm_printf(m, "\tDevice is asleep; skipping register dump\n");
        }

        intel_execlists_show_requests(engine, m, i915_request_show, 8);

        drm_printf(m, "HWSP:\n");
        hexdump(m, engine->status_page.addr, PAGE_SIZE);

        drm_printf(m, "Idle? %s\n", yesno(intel_engine_is_idle(engine)));

        intel_engine_print_breadcrumbs(engine, m);
}

static ktime_t __intel_engine_get_busy_time(struct intel_engine_cs *engine,
                                            ktime_t *now)
{
        ktime_t total = engine->stats.total;

        /*
         * If the engine is executing something at the moment
         * add it to the total.
         */
        *now = ktime_get();
        if (READ_ONCE(engine->stats.active))
                total = ktime_add(total, ktime_sub(*now, engine->stats.start));

        return total;
}

/**
 * intel_engine_get_busy_time() - Return current accumulated engine busyness
 * @engine: engine to report on
 * @now: monotonic timestamp of sampling
 *
 * Returns accumulated time @engine was busy since engine stats were enabled.
 */
ktime_t intel_engine_get_busy_time(struct intel_engine_cs *engine, ktime_t *now)
{
        unsigned int seq;
        ktime_t total;

        do {
                seq = read_seqcount_begin(&engine->stats.lock);
                total = __intel_engine_get_busy_time(engine, now);
        } while (read_seqcount_retry(&engine->stats.lock, seq));

        return total;
}

struct intel_context *
intel_engine_create_virtual(struct intel_engine_cs **siblings,
                            unsigned int count)
{
        if (count == 0)
                return ERR_PTR(-EINVAL);

        if (count == 1)
                return intel_context_create(siblings[0]);

        GEM_BUG_ON(!siblings[0]->cops->create_virtual);
        return siblings[0]->cops->create_virtual(siblings, count);
}

struct i915_request *
intel_engine_execlist_find_hung_request(struct intel_engine_cs *engine)
{
        struct i915_request *request, *active = NULL;

        /*
         * This search does not work in GuC submission mode. However, the GuC
         * will report the hanging context directly to the driver itself. So
         * the driver should never get here when in GuC mode.
         */
        GEM_BUG_ON(intel_uc_uses_guc_submission(&engine->gt->uc));

        /*
         * We are called by the error capture, reset and to dump engine
         * state at random points in time. In particular, note that neither is
         * crucially ordered with an interrupt. After a hang, the GPU is dead
         * and we assume that no more writes can happen (we waited long enough
         * for all writes that were in transaction to be flushed) - adding an
         * extra delay for a recent interrupt is pointless. Hence, we do
         * not need an engine->irq_seqno_barrier() before the seqno reads.
         * At all other times, we must assume the GPU is still running, but
         * we only care about the snapshot of this moment.
         */
        lockdep_assert_held(&engine->sched_engine->lock);

        rcu_read_lock();
        request = execlists_active(&engine->execlists);
        if (request) {
                struct intel_timeline *tl = request->context->timeline;

                list_for_each_entry_from_reverse(request, &tl->requests, link) {
                        if (__i915_request_is_complete(request))
                                break;

                        active = request;
                }
        }
        rcu_read_unlock();
        if (active)
                return active;

        list_for_each_entry(request, &engine->sched_engine->requests,
                            sched.link) {
                if (i915_test_request_state(request) != I915_REQUEST_ACTIVE)
                        continue;

                active = request;
                break;
        }

        return active;
}

#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
#include "mock_engine.c"
#include "selftest_engine.c"
#include "selftest_engine_cs.c"
#endif