root/drivers/gpu/drm/i915/gt/gen2_engine_cs.c
// SPDX-License-Identifier: MIT
/*
 * Copyright © 2020 Intel Corporation
 */

#include "gen2_engine_cs.h"
#include "i915_drv.h"
#include "i915_reg.h"
#include "intel_engine.h"
#include "intel_engine_regs.h"
#include "intel_gpu_commands.h"
#include "intel_gt.h"
#include "intel_gt_irq.h"
#include "intel_ring.h"

int gen2_emit_flush(struct i915_request *rq, u32 mode)
{
        unsigned int num_store_dw = 12;
        u32 cmd, *cs;

        cmd = MI_FLUSH;
        if (mode & EMIT_INVALIDATE)
                cmd |= MI_READ_FLUSH;

        cs = intel_ring_begin(rq, 2 + 4 * num_store_dw);
        if (IS_ERR(cs))
                return PTR_ERR(cs);

        *cs++ = cmd;
        while (num_store_dw--) {
                *cs++ = MI_STORE_DWORD_INDEX;
                *cs++ = I915_GEM_HWS_SCRATCH * sizeof(u32);
                *cs++ = 0;
                *cs++ = MI_FLUSH | MI_NO_WRITE_FLUSH;
        }
        *cs++ = cmd;

        intel_ring_advance(rq, cs);

        return 0;
}

int gen4_emit_flush_rcs(struct i915_request *rq, u32 mode)
{
        u32 cmd, *cs;
        int i;

        /*
         * read/write caches:
         *
         * I915_GEM_DOMAIN_RENDER is always invalidated, but is
         * only flushed if MI_NO_WRITE_FLUSH is unset.  On 965, it is
         * also flushed at 2d versus 3d pipeline switches.
         *
         * read-only caches:
         *
         * I915_GEM_DOMAIN_SAMPLER is flushed on pre-965 if
         * MI_READ_FLUSH is set, and is always flushed on 965.
         *
         * I915_GEM_DOMAIN_COMMAND may not exist?
         *
         * I915_GEM_DOMAIN_INSTRUCTION, which exists on 965, is
         * invalidated when MI_EXE_FLUSH is set.
         *
         * I915_GEM_DOMAIN_VERTEX, which exists on 965, is
         * invalidated with every MI_FLUSH.
         *
         * TLBs:
         *
         * On 965, TLBs associated with I915_GEM_DOMAIN_COMMAND
         * and I915_GEM_DOMAIN_CPU in are invalidated at PTE write and
         * I915_GEM_DOMAIN_RENDER and I915_GEM_DOMAIN_SAMPLER
         * are flushed at any MI_FLUSH.
         */

        cmd = MI_FLUSH;
        if (mode & EMIT_INVALIDATE) {
                cmd |= MI_EXE_FLUSH;
                if (IS_G4X(rq->i915) || GRAPHICS_VER(rq->i915) == 5)
                        cmd |= MI_INVALIDATE_ISP;
        }

        i = 2;
        if (mode & EMIT_INVALIDATE)
                i += 20;

        cs = intel_ring_begin(rq, i);
        if (IS_ERR(cs))
                return PTR_ERR(cs);

        *cs++ = cmd;

        /*
         * A random delay to let the CS invalidate take effect? Without this
         * delay, the GPU relocation path fails as the CS does not see
         * the updated contents. Just as important, if we apply the flushes
         * to the EMIT_FLUSH branch (i.e. immediately after the relocation
         * write and before the invalidate on the next batch), the relocations
         * still fail. This implies that is a delay following invalidation
         * that is required to reset the caches as opposed to a delay to
         * ensure the memory is written.
         */
        if (mode & EMIT_INVALIDATE) {
                *cs++ = GFX_OP_PIPE_CONTROL(4) | PIPE_CONTROL_QW_WRITE;
                *cs++ = intel_gt_scratch_offset(rq->engine->gt,
                                                INTEL_GT_SCRATCH_FIELD_DEFAULT) |
                        PIPE_CONTROL_GLOBAL_GTT;
                *cs++ = 0;
                *cs++ = 0;

                for (i = 0; i < 12; i++)
                        *cs++ = MI_FLUSH;

                *cs++ = GFX_OP_PIPE_CONTROL(4) | PIPE_CONTROL_QW_WRITE;
                *cs++ = intel_gt_scratch_offset(rq->engine->gt,
                                                INTEL_GT_SCRATCH_FIELD_DEFAULT) |
                        PIPE_CONTROL_GLOBAL_GTT;
                *cs++ = 0;
                *cs++ = 0;
        }

        *cs++ = cmd;

        intel_ring_advance(rq, cs);

        return 0;
}

int gen4_emit_flush_vcs(struct i915_request *rq, u32 mode)
{
        u32 *cs;

        cs = intel_ring_begin(rq, 2);
        if (IS_ERR(cs))
                return PTR_ERR(cs);

        *cs++ = MI_FLUSH;
        *cs++ = MI_NOOP;
        intel_ring_advance(rq, cs);

        return 0;
}

static u32 *__gen2_emit_breadcrumb(struct i915_request *rq, u32 *cs,
                                   int flush, int post)
{
        GEM_BUG_ON(i915_request_active_timeline(rq)->hwsp_ggtt != rq->engine->status_page.vma);
        GEM_BUG_ON(offset_in_page(rq->hwsp_seqno) != I915_GEM_HWS_SEQNO_ADDR);

        *cs++ = MI_FLUSH;

        while (flush--) {
                *cs++ = MI_STORE_DWORD_INDEX;
                *cs++ = I915_GEM_HWS_SCRATCH * sizeof(u32);
                *cs++ = rq->fence.seqno;
        }

        while (post--) {
                *cs++ = MI_STORE_DWORD_INDEX;
                *cs++ = I915_GEM_HWS_SEQNO_ADDR;
                *cs++ = rq->fence.seqno;
        }

        *cs++ = MI_USER_INTERRUPT;

        rq->tail = intel_ring_offset(rq, cs);
        assert_ring_tail_valid(rq->ring, rq->tail);

        return cs;
}

u32 *gen2_emit_breadcrumb(struct i915_request *rq, u32 *cs)
{
        return __gen2_emit_breadcrumb(rq, cs, 16, 8);
}

u32 *gen5_emit_breadcrumb(struct i915_request *rq, u32 *cs)
{
        return __gen2_emit_breadcrumb(rq, cs, 8, 8);
}

/* Just userspace ABI convention to limit the wa batch bo to a reasonable size */
#define I830_BATCH_LIMIT SZ_256K
#define I830_TLB_ENTRIES (2)
#define I830_WA_SIZE max(I830_TLB_ENTRIES * SZ_4K, I830_BATCH_LIMIT)
int i830_emit_bb_start(struct i915_request *rq,
                       u64 offset, u32 len,
                       unsigned int dispatch_flags)
{
        u32 *cs, cs_offset =
                intel_gt_scratch_offset(rq->engine->gt,
                                        INTEL_GT_SCRATCH_FIELD_DEFAULT);

        GEM_BUG_ON(rq->engine->gt->scratch->size < I830_WA_SIZE);

        cs = intel_ring_begin(rq, 6);
        if (IS_ERR(cs))
                return PTR_ERR(cs);

        /* Evict the invalid PTE TLBs */
        *cs++ = COLOR_BLT_CMD | BLT_WRITE_RGBA;
        *cs++ = BLT_DEPTH_32 | BLT_ROP_COLOR_COPY | 4096;
        *cs++ = I830_TLB_ENTRIES << 16 | 4; /* load each page */
        *cs++ = cs_offset;
        *cs++ = 0xdeadbeef;
        *cs++ = MI_NOOP;
        intel_ring_advance(rq, cs);

        if ((dispatch_flags & I915_DISPATCH_PINNED) == 0) {
                if (len > I830_BATCH_LIMIT)
                        return -ENOSPC;

                cs = intel_ring_begin(rq, 6 + 2);
                if (IS_ERR(cs))
                        return PTR_ERR(cs);

                /*
                 * Blit the batch (which has now all relocs applied) to the
                 * stable batch scratch bo area (so that the CS never
                 * stumbles over its tlb invalidation bug) ...
                 */
                *cs++ = SRC_COPY_BLT_CMD | BLT_WRITE_RGBA | (6 - 2);
                *cs++ = BLT_DEPTH_32 | BLT_ROP_SRC_COPY | 4096;
                *cs++ = DIV_ROUND_UP(len, 4096) << 16 | 4096;
                *cs++ = cs_offset;
                *cs++ = 4096;
                *cs++ = offset;

                *cs++ = MI_FLUSH;
                *cs++ = MI_NOOP;
                intel_ring_advance(rq, cs);

                /* ... and execute it. */
                offset = cs_offset;
        }

        if (!(dispatch_flags & I915_DISPATCH_SECURE))
                offset |= MI_BATCH_NON_SECURE;

        cs = intel_ring_begin(rq, 2);
        if (IS_ERR(cs))
                return PTR_ERR(cs);

        *cs++ = MI_BATCH_BUFFER_START | MI_BATCH_GTT;
        *cs++ = offset;
        intel_ring_advance(rq, cs);

        return 0;
}

int gen2_emit_bb_start(struct i915_request *rq,
                       u64 offset, u32 len,
                       unsigned int dispatch_flags)
{
        u32 *cs;

        if (!(dispatch_flags & I915_DISPATCH_SECURE))
                offset |= MI_BATCH_NON_SECURE;

        cs = intel_ring_begin(rq, 2);
        if (IS_ERR(cs))
                return PTR_ERR(cs);

        *cs++ = MI_BATCH_BUFFER_START | MI_BATCH_GTT;
        *cs++ = offset;
        intel_ring_advance(rq, cs);

        return 0;
}

int gen4_emit_bb_start(struct i915_request *rq,
                       u64 offset, u32 length,
                       unsigned int dispatch_flags)
{
        u32 security;
        u32 *cs;

        security = MI_BATCH_NON_SECURE_I965;
        if (dispatch_flags & I915_DISPATCH_SECURE)
                security = 0;

        cs = intel_ring_begin(rq, 2);
        if (IS_ERR(cs))
                return PTR_ERR(cs);

        *cs++ = MI_BATCH_BUFFER_START | MI_BATCH_GTT | security;
        *cs++ = offset;
        intel_ring_advance(rq, cs);

        return 0;
}

void gen2_irq_enable(struct intel_engine_cs *engine)
{
        engine->i915->gen2_imr_mask &= ~engine->irq_enable_mask;
        intel_uncore_write(engine->uncore, GEN2_IMR, engine->i915->gen2_imr_mask);
        intel_uncore_posting_read_fw(engine->uncore, GEN2_IMR);
}

void gen2_irq_disable(struct intel_engine_cs *engine)
{
        engine->i915->gen2_imr_mask |= engine->irq_enable_mask;
        intel_uncore_write(engine->uncore, GEN2_IMR, engine->i915->gen2_imr_mask);
}

void gen5_irq_enable(struct intel_engine_cs *engine)
{
        gen5_gt_enable_irq(engine->gt, engine->irq_enable_mask);
}

void gen5_irq_disable(struct intel_engine_cs *engine)
{
        gen5_gt_disable_irq(engine->gt, engine->irq_enable_mask);
}