// SPDX-License-Identifier: MIT
/*
 * Copyright © 2019 Intel Corporation
 */

#include "debugfs_gt.h"

#include "gem/i915_gem_lmem.h"
#include "i915_drv.h"
#include "intel_context.h"
#include "intel_gt.h"
#include "intel_gt_buffer_pool.h"
#include "intel_gt_clock_utils.h"
#include "intel_gt_pm.h"
#include "intel_gt_requests.h"
#include "intel_migrate.h"
#include "intel_mocs.h"
#include "intel_rc6.h"
#include "intel_renderstate.h"
#include "intel_rps.h"
#include "intel_uncore.h"
#include "intel_pm.h"
#include "shmem_utils.h"

void intel_gt_init_early(struct intel_gt *gt, struct drm_i915_private *i915)
{
        gt->i915 = i915;
        gt->uncore = &i915->uncore;

        spin_lock_init(&gt->irq_lock);

        INIT_LIST_HEAD(&gt->closed_vma);
        spin_lock_init(&gt->closed_lock);

        init_llist_head(&gt->watchdog.list);
        INIT_WORK(&gt->watchdog.work, intel_gt_watchdog_work);

        intel_gt_init_buffer_pool(gt);
        intel_gt_init_reset(gt);
        intel_gt_init_requests(gt);
        intel_gt_init_timelines(gt);
        intel_gt_pm_init_early(gt);

        intel_uc_init_early(&gt->uc);
        intel_rps_init_early(&gt->rps);
}

int intel_gt_probe_lmem(struct intel_gt *gt)
{
        struct drm_i915_private *i915 = gt->i915;
        struct intel_memory_region *mem;
        int id;
        int err;

        mem = intel_gt_setup_lmem(gt);
        if (mem == ERR_PTR(-ENODEV))
                mem = intel_gt_setup_fake_lmem(gt);
        if (IS_ERR(mem)) {
                err = PTR_ERR(mem);
                if (err == -ENODEV)
                        return 0;

                drm_err(&i915->drm,
                        "Failed to setup region(%d) type=%d\n",
                        err, INTEL_MEMORY_LOCAL);
                return err;
        }

        id = INTEL_REGION_LMEM;

        mem->id = id;

        intel_memory_region_set_name(mem, "local%u", mem->instance);

        GEM_BUG_ON(!HAS_REGION(i915, id));
        GEM_BUG_ON(i915->mm.regions[id]);
        i915->mm.regions[id] = mem;

        return 0;
}

void intel_gt_init_hw_early(struct intel_gt *gt, struct i915_ggtt *ggtt)
{
        gt->ggtt = ggtt;
}

static const struct intel_mmio_range icl_l3bank_steering_table[] = {
        { 0x00B100, 0x00B3FF },
        {},
};

static const struct intel_mmio_range xehpsdv_mslice_steering_table[] = {
        { 0x004000, 0x004AFF },
        { 0x00C800, 0x00CFFF },
        { 0x00DD00, 0x00DDFF },
        { 0x00E900, 0x00FFFF }, /* 0xEA00 - OxEFFF is unused */
        {},
};

static const struct intel_mmio_range xehpsdv_lncf_steering_table[] = {
        { 0x00B000, 0x00B0FF },
        { 0x00D800, 0x00D8FF },
        {},
};

static const struct intel_mmio_range dg2_lncf_steering_table[] = {
        { 0x00B000, 0x00B0FF },
        { 0x00D880, 0x00D8FF },
        {},
};

static u16 slicemask(struct intel_gt *gt, int count)
{
        u64 dss_mask = intel_sseu_get_subslices(&gt->info.sseu, 0);

        return intel_slicemask_from_dssmask(dss_mask, count);
}

int intel_gt_init_mmio(struct intel_gt *gt)
{
        struct drm_i915_private *i915 = gt->i915;

        intel_gt_init_clock_frequency(gt);

        intel_uc_init_mmio(&gt->uc);
        intel_sseu_info_init(gt);

        /*
         * An mslice is unavailable only if both the meml3 for the slice is
         * disabled *and* all of the DSS in the slice (quadrant) are disabled.
         */
        if (HAS_MSLICES(i915))
                gt->info.mslice_mask =
                        slicemask(gt, GEN_DSS_PER_MSLICE) |
                        (intel_uncore_read(gt->uncore, GEN10_MIRROR_FUSE3) &
                         GEN12_MEML3_EN_MASK);

        if (IS_DG2(i915)) {
                gt->steering_table[MSLICE] = xehpsdv_mslice_steering_table;
                gt->steering_table[LNCF] = dg2_lncf_steering_table;
        } else if (IS_XEHPSDV(i915)) {
                gt->steering_table[MSLICE] = xehpsdv_mslice_steering_table;
                gt->steering_table[LNCF] = xehpsdv_lncf_steering_table;
        } else if (GRAPHICS_VER(i915) >= 11 &&
                   GRAPHICS_VER_FULL(i915) < IP_VER(12, 50)) {
                gt->steering_table[L3BANK] = icl_l3bank_steering_table;
                gt->info.l3bank_mask =
                        ~intel_uncore_read(gt->uncore, GEN10_MIRROR_FUSE3) &
                        GEN10_L3BANK_MASK;
        } else if (HAS_MSLICES(i915)) {
                MISSING_CASE(INTEL_INFO(i915)->platform);
        }

        return intel_engines_init_mmio(gt);
}

static void init_unused_ring(struct intel_gt *gt, u32 base)
{
        struct intel_uncore *uncore = gt->uncore;

        intel_uncore_write(uncore, RING_CTL(base), 0);
        intel_uncore_write(uncore, RING_HEAD(base), 0);
        intel_uncore_write(uncore, RING_TAIL(base), 0);
        intel_uncore_write(uncore, RING_START(base), 0);
}

static void init_unused_rings(struct intel_gt *gt)
{
        struct drm_i915_private *i915 = gt->i915;

        if (IS_I830(i915)) {
                init_unused_ring(gt, PRB1_BASE);
                init_unused_ring(gt, SRB0_BASE);
                init_unused_ring(gt, SRB1_BASE);
                init_unused_ring(gt, SRB2_BASE);
                init_unused_ring(gt, SRB3_BASE);
        } else if (GRAPHICS_VER(i915) == 2) {
                init_unused_ring(gt, SRB0_BASE);
                init_unused_ring(gt, SRB1_BASE);
        } else if (GRAPHICS_VER(i915) == 3) {
                init_unused_ring(gt, PRB1_BASE);
                init_unused_ring(gt, PRB2_BASE);
        }
}

int intel_gt_init_hw(struct intel_gt *gt)
{
        struct drm_i915_private *i915 = gt->i915;
        struct intel_uncore *uncore = gt->uncore;
        int ret;

        gt->last_init_time = ktime_get();

        /* Double layer security blanket, see i915_gem_init() */
        intel_uncore_forcewake_get(uncore, FORCEWAKE_ALL);

        if (HAS_EDRAM(i915) && GRAPHICS_VER(i915) < 9)
                intel_uncore_rmw(uncore, HSW_IDICR, 0, IDIHASHMSK(0xf));

        if (IS_HASWELL(i915))
                intel_uncore_write(uncore,
                                   MI_PREDICATE_RESULT_2,
                                   IS_HSW_GT3(i915) ?
                                   LOWER_SLICE_ENABLED : LOWER_SLICE_DISABLED);

        /* Apply the GT workarounds... */
        intel_gt_apply_workarounds(gt);
        /* ...and determine whether they are sticking. */
        intel_gt_verify_workarounds(gt, "init");

        intel_gt_init_swizzling(gt);

        /*
         * At least 830 can leave some of the unused rings
         * "active" (ie. head != tail) after resume which
         * will prevent c3 entry. Makes sure all unused rings
         * are totally idle.
         */
        init_unused_rings(gt);

        ret = i915_ppgtt_init_hw(gt);
        if (ret) {
                DRM_ERROR("Enabling PPGTT failed (%d)\n", ret);
                goto out;
        }

        /* We can't enable contexts until all firmware is loaded */
        ret = intel_uc_init_hw(&gt->uc);
        if (ret) {
                i915_probe_error(i915, "Enabling uc failed (%d)\n", ret);
                goto out;
        }

        intel_mocs_init(gt);

out:
        intel_uncore_forcewake_put(uncore, FORCEWAKE_ALL);
        return ret;
}

static void rmw_set(struct intel_uncore *uncore, i915_reg_t reg, u32 set)
{
        intel_uncore_rmw(uncore, reg, 0, set);
}

static void rmw_clear(struct intel_uncore *uncore, i915_reg_t reg, u32 clr)
{
        intel_uncore_rmw(uncore, reg, clr, 0);
}

static void clear_register(struct intel_uncore *uncore, i915_reg_t reg)
{
        intel_uncore_rmw(uncore, reg, 0, 0);
}

static void gen6_clear_engine_error_register(struct intel_engine_cs *engine)
{
        GEN6_RING_FAULT_REG_RMW(engine, RING_FAULT_VALID, 0);
        GEN6_RING_FAULT_REG_POSTING_READ(engine);
}

void
intel_gt_clear_error_registers(struct intel_gt *gt,
                               intel_engine_mask_t engine_mask)
{
        struct drm_i915_private *i915 = gt->i915;
        struct intel_uncore *uncore = gt->uncore;
        u32 eir;

        if (GRAPHICS_VER(i915) != 2)
                clear_register(uncore, PGTBL_ER);

        if (GRAPHICS_VER(i915) < 4)
                clear_register(uncore, IPEIR(RENDER_RING_BASE));
        else
                clear_register(uncore, IPEIR_I965);

        clear_register(uncore, EIR);
        eir = intel_uncore_read(uncore, EIR);
        if (eir) {
                /*
                 * some errors might have become stuck,
                 * mask them.
                 */
                DRM_DEBUG_DRIVER("EIR stuck: 0x%08x, masking\n", eir);
                rmw_set(uncore, EMR, eir);
                intel_uncore_write(uncore, GEN2_IIR,
                                   I915_MASTER_ERROR_INTERRUPT);
        }

        if (GRAPHICS_VER(i915) >= 12) {
                rmw_clear(uncore, GEN12_RING_FAULT_REG, RING_FAULT_VALID);
                intel_uncore_posting_read(uncore, GEN12_RING_FAULT_REG);
        } else if (GRAPHICS_VER(i915) >= 8) {
                rmw_clear(uncore, GEN8_RING_FAULT_REG, RING_FAULT_VALID);
                intel_uncore_posting_read(uncore, GEN8_RING_FAULT_REG);
        } else if (GRAPHICS_VER(i915) >= 6) {
                struct intel_engine_cs *engine;
                enum intel_engine_id id;

                for_each_engine_masked(engine, gt, engine_mask, id)
                        gen6_clear_engine_error_register(engine);
        }
}

static void gen6_check_faults(struct intel_gt *gt)
{
        struct intel_engine_cs *engine;
        enum intel_engine_id id;
        u32 fault;

        for_each_engine(engine, gt, id) {
                fault = GEN6_RING_FAULT_REG_READ(engine);
                if (fault & RING_FAULT_VALID) {
                        drm_dbg(&engine->i915->drm, "Unexpected fault\n"
                                "\tAddr: 0x%08lx\n"
                                "\tAddress space: %s\n"
                                "\tSource ID: %d\n"
                                "\tType: %d\n",
                                fault & PAGE_MASK,
                                fault & RING_FAULT_GTTSEL_MASK ?
                                "GGTT" : "PPGTT",
                                RING_FAULT_SRCID(fault),
                                RING_FAULT_FAULT_TYPE(fault));
                }
        }
}

static void gen8_check_faults(struct intel_gt *gt)
{
        struct intel_uncore *uncore = gt->uncore;
        i915_reg_t fault_reg, fault_data0_reg, fault_data1_reg;
        u32 fault;

        if (GRAPHICS_VER(gt->i915) >= 12) {
                fault_reg = GEN12_RING_FAULT_REG;
                fault_data0_reg = GEN12_FAULT_TLB_DATA0;
                fault_data1_reg = GEN12_FAULT_TLB_DATA1;
        } else {
                fault_reg = GEN8_RING_FAULT_REG;
                fault_data0_reg = GEN8_FAULT_TLB_DATA0;
                fault_data1_reg = GEN8_FAULT_TLB_DATA1;
        }

        fault = intel_uncore_read(uncore, fault_reg);
        if (fault & RING_FAULT_VALID) {
                u32 fault_data0, fault_data1;
                u64 fault_addr;

                fault_data0 = intel_uncore_read(uncore, fault_data0_reg);
                fault_data1 = intel_uncore_read(uncore, fault_data1_reg);

                fault_addr = ((u64)(fault_data1 & FAULT_VA_HIGH_BITS) << 44) |
                             ((u64)fault_data0 << 12);

                drm_dbg(&uncore->i915->drm, "Unexpected fault\n"
                        "\tAddr: 0x%08x_%08x\n"
                        "\tAddress space: %s\n"
                        "\tEngine ID: %d\n"
                        "\tSource ID: %d\n"
                        "\tType: %d\n",
                        upper_32_bits(fault_addr), lower_32_bits(fault_addr),
                        fault_data1 & FAULT_GTT_SEL ? "GGTT" : "PPGTT",
                        GEN8_RING_FAULT_ENGINE_ID(fault),
                        RING_FAULT_SRCID(fault),
                        RING_FAULT_FAULT_TYPE(fault));
        }
}

void intel_gt_check_and_clear_faults(struct intel_gt *gt)
{
        struct drm_i915_private *i915 = gt->i915;

        /* From GEN8 onwards we only have one 'All Engine Fault Register' */
        if (GRAPHICS_VER(i915) >= 8)
                gen8_check_faults(gt);
        else if (GRAPHICS_VER(i915) >= 6)
                gen6_check_faults(gt);
        else
                return;

        intel_gt_clear_error_registers(gt, ALL_ENGINES);
}

void intel_gt_flush_ggtt_writes(struct intel_gt *gt)
{
        struct intel_uncore *uncore = gt->uncore;
        intel_wakeref_t wakeref;

        /*
         * No actual flushing is required for the GTT write domain for reads
         * from the GTT domain. Writes to it "immediately" go to main memory
         * as far as we know, so there's no chipset flush. It also doesn't
         * land in the GPU render cache.
         *
         * However, we do have to enforce the order so that all writes through
         * the GTT land before any writes to the device, such as updates to
         * the GATT itself.
         *
         * We also have to wait a bit for the writes to land from the GTT.
         * An uncached read (i.e. mmio) seems to be ideal for the round-trip
         * timing. This issue has only been observed when switching quickly
         * between GTT writes and CPU reads from inside the kernel on recent hw,
         * and it appears to only affect discrete GTT blocks (i.e. on LLC
         * system agents we cannot reproduce this behaviour, until Cannonlake
         * that was!).
         */

        wmb();

        if (INTEL_INFO(gt->i915)->has_coherent_ggtt)
                return;

        intel_gt_chipset_flush(gt);

        with_intel_runtime_pm_if_in_use(uncore->rpm, wakeref) {
                unsigned long flags;

                spin_lock_irqsave(&uncore->lock, flags);
                intel_uncore_posting_read_fw(uncore,
                                             RING_HEAD(RENDER_RING_BASE));
                spin_unlock_irqrestore(&uncore->lock, flags);
        }
}

void intel_gt_chipset_flush(struct intel_gt *gt)
{
        wmb();
        if (GRAPHICS_VER(gt->i915) < 6)
                intel_gtt_chipset_flush();
}

void intel_gt_driver_register(struct intel_gt *gt)
{
        intel_rps_driver_register(&gt->rps);

        debugfs_gt_register(gt);
}

static int intel_gt_init_scratch(struct intel_gt *gt, unsigned int size)
{
        struct drm_i915_private *i915 = gt->i915;
        struct drm_i915_gem_object *obj;
        struct i915_vma *vma;
        int ret;

        obj = i915_gem_object_create_lmem(i915, size, I915_BO_ALLOC_VOLATILE);
        if (IS_ERR(obj))
                obj = i915_gem_object_create_stolen(i915, size);
        if (IS_ERR(obj))
                obj = i915_gem_object_create_internal(i915, size);
        if (IS_ERR(obj)) {
                drm_err(&i915->drm, "Failed to allocate scratch page\n");
                return PTR_ERR(obj);
        }

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

        ret = i915_ggtt_pin(vma, NULL, 0, PIN_HIGH);
        if (ret)
                goto err_unref;

        gt->scratch = i915_vma_make_unshrinkable(vma);

        return 0;

err_unref:
        i915_gem_object_put(obj);
        return ret;
}

static void intel_gt_fini_scratch(struct intel_gt *gt)
{
        i915_vma_unpin_and_release(&gt->scratch, 0);
}

static struct i915_address_space *kernel_vm(struct intel_gt *gt)
{
        if (INTEL_PPGTT(gt->i915) > INTEL_PPGTT_ALIASING)
                return &i915_ppgtt_create(gt)->vm;
        else
                return i915_vm_get(&gt->ggtt->vm);
}

static int __engines_record_defaults(struct intel_gt *gt)
{
        struct i915_request *requests[I915_NUM_ENGINES] = {};
        struct intel_engine_cs *engine;
        enum intel_engine_id id;
        int err = 0;

        /*
         * As we reset the gpu during very early sanitisation, the current
         * register state on the GPU should reflect its defaults values.
         * We load a context onto the hw (with restore-inhibit), then switch
         * over to a second context to save that default register state. We
         * can then prime every new context with that state so they all start
         * from the same default HW values.
         */

        for_each_engine(engine, gt, id) {
                struct intel_renderstate so;
                struct intel_context *ce;
                struct i915_request *rq;

                /* We must be able to switch to something! */
                GEM_BUG_ON(!engine->kernel_context);

                ce = intel_context_create(engine);
                if (IS_ERR(ce)) {
                        err = PTR_ERR(ce);
                        goto out;
                }

                err = intel_renderstate_init(&so, ce);
                if (err)
                        goto err;

                rq = i915_request_create(ce);
                if (IS_ERR(rq)) {
                        err = PTR_ERR(rq);
                        goto err_fini;
                }

                err = intel_engine_emit_ctx_wa(rq);
                if (err)
                        goto err_rq;

                err = intel_renderstate_emit(&so, rq);
                if (err)
                        goto err_rq;

err_rq:
                requests[id] = i915_request_get(rq);
                i915_request_add(rq);
err_fini:
                intel_renderstate_fini(&so, ce);
err:
                if (err) {
                        intel_context_put(ce);
                        goto out;
                }
        }

        /* Flush the default context image to memory, and enable powersaving. */
        if (intel_gt_wait_for_idle(gt, I915_GEM_IDLE_TIMEOUT) == -ETIME) {
                err = -EIO;
                goto out;
        }

        for (id = 0; id < ARRAY_SIZE(requests); id++) {
                struct i915_request *rq;
                struct file *state;

                rq = requests[id];
                if (!rq)
                        continue;

                if (rq->fence.error) {
                        err = -EIO;
                        goto out;
                }

                GEM_BUG_ON(!test_bit(CONTEXT_ALLOC_BIT, &rq->context->flags));
                if (!rq->context->state)
                        continue;

                /* Keep a copy of the state's backing pages; free the obj */
                state = shmem_create_from_object(rq->context->state->obj);
                if (IS_ERR(state)) {
                        err = PTR_ERR(state);
                        goto out;
                }
                rq->engine->default_state = state;
        }

out:
        /*
         * If we have to abandon now, we expect the engines to be idle
         * and ready to be torn-down. The quickest way we can accomplish
         * this is by declaring ourselves wedged.
         */
        if (err)
                intel_gt_set_wedged(gt);

        for (id = 0; id < ARRAY_SIZE(requests); id++) {
                struct intel_context *ce;
                struct i915_request *rq;

                rq = requests[id];
                if (!rq)
                        continue;

                ce = rq->context;
                i915_request_put(rq);
                intel_context_put(ce);
        }
        return err;
}

static int __engines_verify_workarounds(struct intel_gt *gt)
{
        struct intel_engine_cs *engine;
        enum intel_engine_id id;
        int err = 0;

        if (!IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM))
                return 0;

        for_each_engine(engine, gt, id) {
                if (intel_engine_verify_workarounds(engine, "load"))
                        err = -EIO;
        }

        /* Flush and restore the kernel context for safety */
        if (intel_gt_wait_for_idle(gt, I915_GEM_IDLE_TIMEOUT) == -ETIME)
                err = -EIO;

        return err;
}

static void __intel_gt_disable(struct intel_gt *gt)
{
        intel_gt_set_wedged_on_fini(gt);

        intel_gt_suspend_prepare(gt);
        intel_gt_suspend_late(gt);

        GEM_BUG_ON(intel_gt_pm_is_awake(gt));
}

int intel_gt_wait_for_idle(struct intel_gt *gt, long timeout)
{
        long remaining_timeout;

        /* If the device is asleep, we have no requests outstanding */
        if (!intel_gt_pm_is_awake(gt))
                return 0;

        while ((timeout = intel_gt_retire_requests_timeout(gt, timeout,
                                                           &remaining_timeout)) > 0) {
                cond_resched();
                if (signal_pending(current))
                        return -EINTR;
        }

        return timeout ? timeout : intel_uc_wait_for_idle(&gt->uc,
                                                          remaining_timeout);
}

int intel_gt_init(struct intel_gt *gt)
{
        int err;

        err = i915_inject_probe_error(gt->i915, -ENODEV);
        if (err)
                return err;

        /*
         * This is just a security blanket to placate dragons.
         * On some systems, we very sporadically observe that the first TLBs
         * used by the CS may be stale, despite us poking the TLB reset. If
         * we hold the forcewake during initialisation these problems
         * just magically go away.
         */
        intel_uncore_forcewake_get(gt->uncore, FORCEWAKE_ALL);

        err = intel_gt_init_scratch(gt,
                                    GRAPHICS_VER(gt->i915) == 2 ? SZ_256K : SZ_4K);
        if (err)
                goto out_fw;

        intel_gt_pm_init(gt);

        gt->vm = kernel_vm(gt);
        if (!gt->vm) {
                err = -ENOMEM;
                goto err_pm;
        }

        err = intel_engines_init(gt);
        if (err)
                goto err_engines;

        err = intel_uc_init(&gt->uc);
        if (err)
                goto err_engines;

        err = intel_gt_resume(gt);
        if (err)
                goto err_uc_init;

        err = __engines_record_defaults(gt);
        if (err)
                goto err_gt;

        err = __engines_verify_workarounds(gt);
        if (err)
                goto err_gt;

        intel_uc_init_late(&gt->uc);

        err = i915_inject_probe_error(gt->i915, -EIO);
        if (err)
                goto err_gt;

        intel_migrate_init(&gt->migrate, gt);

        goto out_fw;
err_gt:
        __intel_gt_disable(gt);
        intel_uc_fini_hw(&gt->uc);
err_uc_init:
        intel_uc_fini(&gt->uc);
err_engines:
        intel_engines_release(gt);
        i915_vm_put(fetch_and_zero(&gt->vm));
err_pm:
        intel_gt_pm_fini(gt);
        intel_gt_fini_scratch(gt);
out_fw:
        if (err)
                intel_gt_set_wedged_on_init(gt);
        intel_uncore_forcewake_put(gt->uncore, FORCEWAKE_ALL);
        return err;
}

void intel_gt_driver_remove(struct intel_gt *gt)
{
        __intel_gt_disable(gt);

        intel_migrate_fini(&gt->migrate);
        intel_uc_driver_remove(&gt->uc);

        intel_engines_release(gt);
}

void intel_gt_driver_unregister(struct intel_gt *gt)
{
        intel_wakeref_t wakeref;

        intel_rps_driver_unregister(&gt->rps);

        /*
         * Upon unregistering the device to prevent any new users, cancel
         * all in-flight requests so that we can quickly unbind the active
         * resources.
         */
        intel_gt_set_wedged(gt);

        /* Scrub all HW state upon release */
        with_intel_runtime_pm(gt->uncore->rpm, wakeref)
                __intel_gt_reset(gt, ALL_ENGINES);
}

void intel_gt_driver_release(struct intel_gt *gt)
{
        struct i915_address_space *vm;

        vm = fetch_and_zero(&gt->vm);
        if (vm) /* FIXME being called twice on error paths :( */
                i915_vm_put(vm);

        intel_gt_pm_fini(gt);
        intel_gt_fini_scratch(gt);
        intel_gt_fini_buffer_pool(gt);
}

void intel_gt_driver_late_release(struct intel_gt *gt)
{
        /* We need to wait for inflight RCU frees to release their grip */
        rcu_barrier();

        intel_uc_driver_late_release(&gt->uc);
        intel_gt_fini_requests(gt);
        intel_gt_fini_reset(gt);
        intel_gt_fini_timelines(gt);
        intel_engines_free(gt);
}

/**
 * intel_gt_reg_needs_read_steering - determine whether a register read
 *     requires explicit steering
 * @gt: GT structure
 * @reg: the register to check steering requirements for
 * @type: type of multicast steering to check
 *
 * Determines whether @reg needs explicit steering of a specific type for
 * reads.
 *
 * Returns false if @reg does not belong to a register range of the given
 * steering type, or if the default (subslice-based) steering IDs are suitable
 * for @type steering too.
 */
static bool intel_gt_reg_needs_read_steering(struct intel_gt *gt,
                                             i915_reg_t reg,
                                             enum intel_steering_type type)
{
        const u32 offset = i915_mmio_reg_offset(reg);
        const struct intel_mmio_range *entry;

        if (likely(!intel_gt_needs_read_steering(gt, type)))
                return false;

        for (entry = gt->steering_table[type]; entry->end; entry++) {
                if (offset >= entry->start && offset <= entry->end)
                        return true;
        }

        return false;
}

/**
 * intel_gt_get_valid_steering - determines valid IDs for a class of MCR steering
 * @gt: GT structure
 * @type: multicast register type
 * @sliceid: Slice ID returned
 * @subsliceid: Subslice ID returned
 *
 * Determines sliceid and subsliceid values that will steer reads
 * of a specific multicast register class to a valid value.
 */
static void intel_gt_get_valid_steering(struct intel_gt *gt,
                                        enum intel_steering_type type,
                                        u8 *sliceid, u8 *subsliceid)
{
        switch (type) {
        case L3BANK:
                GEM_DEBUG_WARN_ON(!gt->info.l3bank_mask); /* should be impossible! */

                *sliceid = 0;           /* unused */
                *subsliceid = __ffs(gt->info.l3bank_mask);
                break;
        case MSLICE:
                GEM_DEBUG_WARN_ON(!gt->info.mslice_mask); /* should be impossible! */

                *sliceid = __ffs(gt->info.mslice_mask);
                *subsliceid = 0;        /* unused */
                break;
        case LNCF:
                GEM_DEBUG_WARN_ON(!gt->info.mslice_mask); /* should be impossible! */

                /*
                 * An LNCF is always present if its mslice is present, so we
                 * can safely just steer to LNCF 0 in all cases.
                 */
                *sliceid = __ffs(gt->info.mslice_mask) << 1;
                *subsliceid = 0;        /* unused */
                break;
        default:
                MISSING_CASE(type);
                *sliceid = 0;
                *subsliceid = 0;
        }
}

/**
 * intel_gt_read_register_fw - reads a GT register with support for multicast
 * @gt: GT structure
 * @reg: register to read
 *
 * This function will read a GT register.  If the register is a multicast
 * register, the read will be steered to a valid instance (i.e., one that
 * isn't fused off or powered down by power gating).
 *
 * Returns the value from a valid instance of @reg.
 */
u32 intel_gt_read_register_fw(struct intel_gt *gt, i915_reg_t reg)
{
        int type;
        u8 sliceid, subsliceid;

        for (type = 0; type < NUM_STEERING_TYPES; type++) {
                if (intel_gt_reg_needs_read_steering(gt, reg, type)) {
                        intel_gt_get_valid_steering(gt, type, &sliceid,
                                                    &subsliceid);
                        return intel_uncore_read_with_mcr_steering_fw(gt->uncore,
                                                                      reg,
                                                                      sliceid,
                                                                      subsliceid);
                }
        }

        return intel_uncore_read_fw(gt->uncore, reg);
}

void intel_gt_info_print(const struct intel_gt_info *info,
                         struct drm_printer *p)
{
        drm_printf(p, "available engines: %x\n", info->engine_mask);

        intel_sseu_dump(&info->sseu, p);
}