path: root/src/gallium/drivers/radeonsi/si_cp_dma.c

/*
 * Copyright 2013 Advanced Micro Devices, Inc.
 * All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * on the rights to use, copy, modify, merge, publish, distribute, sub
 * license, and/or sell copies of the Software, and to permit persons to whom
 * the Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHOR(S) AND/OR THEIR SUPPLIERS BE LIABLE FOR ANY CLAIM,
 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
 * USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

#include "si_pipe.h"
#include "sid.h"

/* Set this if you want the ME to wait until CP DMA is done.
 * It should be set on the last CP DMA packet. */
#define CP_DMA_SYNC		(1 << 0)

/* Set this if the source data was used as a destination in a previous CP DMA
 * packet. It's for preventing a read-after-write (RAW) hazard between two
 * CP DMA packets. */
#define CP_DMA_RAW_WAIT		(1 << 1)
#define CP_DMA_DST_IS_GDS	(1 << 2)
#define CP_DMA_CLEAR		(1 << 3)
#define CP_DMA_PFP_SYNC_ME	(1 << 4)
#define CP_DMA_SRC_IS_GDS	(1 << 5)

/* The max number of bytes that can be copied per packet. */
static inline unsigned cp_dma_max_byte_count(struct si_context *sctx)
{
	unsigned max = sctx->chip_class >= GFX9 ?
			       S_414_BYTE_COUNT_GFX9(~0u) :
			       S_414_BYTE_COUNT_GFX6(~0u);

	/* make it aligned for optimal performance */
	return max & ~(SI_CPDMA_ALIGNMENT - 1);
}


/* Emit a CP DMA packet to do a copy from one buffer to another, or to clear
 * a buffer. The size must fit in bits [20:0]. If CP_DMA_CLEAR is set, src_va is a 32-bit
 * clear value.
 */
static void si_emit_cp_dma(struct si_context *sctx, struct radeon_cmdbuf *cs,
			   uint64_t dst_va, uint64_t src_va, unsigned size,
			   unsigned flags, enum si_cache_policy cache_policy)
{
	uint32_t header = 0, command = 0;

	assert(size <= cp_dma_max_byte_count(sctx));
	assert(sctx->chip_class != GFX6 || cache_policy == L2_BYPASS);

	if (sctx->chip_class >= GFX9)
		command |= S_414_BYTE_COUNT_GFX9(size);
	else
		command |= S_414_BYTE_COUNT_GFX6(size);

	/* Sync flags. */
	if (flags & CP_DMA_SYNC)
		header |= S_411_CP_SYNC(1);
	else {
		if (sctx->chip_class >= GFX9)
			command |= S_414_DISABLE_WR_CONFIRM_GFX9(1);
		else
			command |= S_414_DISABLE_WR_CONFIRM_GFX6(1);
	}

	if (flags & CP_DMA_RAW_WAIT)
		command |= S_414_RAW_WAIT(1);

	/* Src and dst flags. */
	if (sctx->chip_class >= GFX9 && !(flags & CP_DMA_CLEAR) &&
	    src_va == dst_va) {
		header |= S_411_DST_SEL(V_411_NOWHERE); /* prefetch only */
	} else if (flags & CP_DMA_DST_IS_GDS) {
		header |= S_411_DST_SEL(V_411_GDS);
		/* GDS increments the address, not CP. */
		command |= S_414_DAS(V_414_REGISTER) |
			   S_414_DAIC(V_414_NO_INCREMENT);
	} else if (sctx->chip_class >= GFX7 && cache_policy != L2_BYPASS) {
		header |= S_411_DST_SEL(V_411_DST_ADDR_TC_L2) |
			  S_500_DST_CACHE_POLICY(cache_policy == L2_STREAM);
	}

	if (flags & CP_DMA_CLEAR) {
		header |= S_411_SRC_SEL(V_411_DATA);
	} else if (flags & CP_DMA_SRC_IS_GDS) {
		header |= S_411_SRC_SEL(V_411_GDS);
		/* Both of these are required for GDS. It does increment the address. */
		command |= S_414_SAS(V_414_REGISTER) |
			   S_414_SAIC(V_414_NO_INCREMENT);
	} else if (sctx->chip_class >= GFX7 && cache_policy != L2_BYPASS) {
		header |= S_411_SRC_SEL(V_411_SRC_ADDR_TC_L2) |
			  S_500_SRC_CACHE_POLICY(cache_policy == L2_STREAM);
	}

	if (sctx->chip_class >= GFX7) {
		radeon_emit(cs, PKT3(PKT3_DMA_DATA, 5, 0));
		radeon_emit(cs, header);
		radeon_emit(cs, src_va);	/* SRC_ADDR_LO [31:0] */
		radeon_emit(cs, src_va >> 32);	/* SRC_ADDR_HI [31:0] */
		radeon_emit(cs, dst_va);	/* DST_ADDR_LO [31:0] */
		radeon_emit(cs, dst_va >> 32);	/* DST_ADDR_HI [31:0] */
		radeon_emit(cs, command);
	} else {
		header |= S_411_SRC_ADDR_HI(src_va >> 32);

		radeon_emit(cs, PKT3(PKT3_CP_DMA, 4, 0));
		radeon_emit(cs, src_va);	/* SRC_ADDR_LO [31:0] */
		radeon_emit(cs, header);	/* SRC_ADDR_HI [15:0] + flags. */
		radeon_emit(cs, dst_va);	/* DST_ADDR_LO [31:0] */
		radeon_emit(cs, (dst_va >> 32) & 0xffff); /* DST_ADDR_HI [15:0] */
		radeon_emit(cs, command);
	}

	/* CP DMA is executed in ME, but index buffers are read by PFP.
	 * This ensures that ME (CP DMA) is idle before PFP starts fetching
	 * indices. If we wanted to execute CP DMA in PFP, this packet
	 * should precede it.
	 */
	if (sctx->has_graphics && flags & CP_DMA_PFP_SYNC_ME) {
		radeon_emit(cs, PKT3(PKT3_PFP_SYNC_ME, 0, 0));
		radeon_emit(cs, 0);
	}
}

void si_cp_dma_wait_for_idle(struct si_context *sctx)
{
	/* Issue a dummy DMA that copies zero bytes.
	 *
	 * The DMA engine will see that there's no work to do and skip this
	 * DMA request, however, the CP will see the sync flag and still wait
	 * for all DMAs to complete.
	 */
	si_emit_cp_dma(sctx, sctx->gfx_cs, 0, 0, 0, CP_DMA_SYNC, L2_BYPASS);
}

static void si_cp_dma_prepare(struct si_context *sctx, struct pipe_resource *dst,
			      struct pipe_resource *src, unsigned byte_count,
			      uint64_t remaining_size, unsigned user_flags,
			      enum si_coherency coher, bool *is_first,
			      unsigned *packet_flags)
{
	/* Fast exit for a CPDMA prefetch. */
	if ((user_flags & SI_CPDMA_SKIP_ALL) == SI_CPDMA_SKIP_ALL) {
		*is_first = false;
		return;
	}

	if (!(user_flags & SI_CPDMA_SKIP_BO_LIST_UPDATE)) {
		/* Count memory usage in so that need_cs_space can take it into account. */
		if (dst)
			si_context_add_resource_size(sctx, dst);
		if (src)
			si_context_add_resource_size(sctx, src);
	}

	if (!(user_flags & SI_CPDMA_SKIP_CHECK_CS_SPACE))
		si_need_gfx_cs_space(sctx);

	/* This must be done after need_cs_space. */
	if (!(user_flags & SI_CPDMA_SKIP_BO_LIST_UPDATE)) {
		if (dst)
			radeon_add_to_buffer_list(sctx, sctx->gfx_cs,
						  si_resource(dst),
						  RADEON_USAGE_WRITE, RADEON_PRIO_CP_DMA);
		if (src)
			radeon_add_to_buffer_list(sctx, sctx->gfx_cs,
						  si_resource(src),
						  RADEON_USAGE_READ, RADEON_PRIO_CP_DMA);
	}

	/* Flush the caches for the first copy only.
	 * Also wait for the previous CP DMA operations.
	 */
	if (!(user_flags & SI_CPDMA_SKIP_GFX_SYNC) && sctx->flags)
		sctx->emit_cache_flush(sctx);

	if (!(user_flags & SI_CPDMA_SKIP_SYNC_BEFORE) && *is_first &&
	    !(*packet_flags & CP_DMA_CLEAR))
		*packet_flags |= CP_DMA_RAW_WAIT;

	*is_first = false;

	/* Do the synchronization after the last dma, so that all data
	 * is written to memory.
	 */
	if (!(user_flags & SI_CPDMA_SKIP_SYNC_AFTER) &&
	    byte_count == remaining_size) {
		*packet_flags |= CP_DMA_SYNC;

		if (coher == SI_COHERENCY_SHADER)
			*packet_flags |= CP_DMA_PFP_SYNC_ME;
	}
}

void si_cp_dma_clear_buffer(struct si_context *sctx, struct radeon_cmdbuf *cs,
			    struct pipe_resource *dst, uint64_t offset,
			    uint64_t size, unsigned value, unsigned user_flags,
			    enum si_coherency coher, enum si_cache_policy cache_policy)
{
	struct si_resource *sdst = si_resource(dst);
	uint64_t va = (sdst ? sdst->gpu_address : 0) + offset;
	bool is_first = true;

	assert(size && size % 4 == 0);

	/* Mark the buffer range of destination as valid (initialized),
	 * so that transfer_map knows it should wait for the GPU when mapping
	 * that range. */
	if (sdst)
		util_range_add(dst, &sdst->valid_buffer_range, offset, offset + size);

	/* Flush the caches. */
	if (sdst && !(user_flags & SI_CPDMA_SKIP_GFX_SYNC)) {
		sctx->flags |= SI_CONTEXT_PS_PARTIAL_FLUSH |
			       SI_CONTEXT_CS_PARTIAL_FLUSH |
			       si_get_flush_flags(sctx, coher, cache_policy);
	}

	while (size) {
		unsigned byte_count = MIN2(size, cp_dma_max_byte_count(sctx));
		unsigned dma_flags = CP_DMA_CLEAR | (sdst ? 0 : CP_DMA_DST_IS_GDS);

		si_cp_dma_prepare(sctx, dst, NULL, byte_count, size, user_flags,
				  coher, &is_first, &dma_flags);

		/* Emit the clear packet. */
		si_emit_cp_dma(sctx, cs, va, value, byte_count, dma_flags, cache_policy);

		size -= byte_count;
		va += byte_count;
	}

	if (sdst && cache_policy != L2_BYPASS)
		sdst->TC_L2_dirty = true;

	/* If it's not a framebuffer fast clear... */
	if (coher == SI_COHERENCY_SHADER) {
		sctx->num_cp_dma_calls++;
		si_prim_discard_signal_next_compute_ib_start(sctx);
	}
}

/**
 * Realign the CP DMA engine. This must be done after a copy with an unaligned
 * size.
 *
 * \param size  Remaining size to the CP DMA alignment.
 */
static void si_cp_dma_realign_engine(struct si_context *sctx, unsigned size,
				     unsigned user_flags, enum si_coherency coher,
				     enum si_cache_policy cache_policy,
				     bool *is_first)
{
	uint64_t va;
	unsigned dma_flags = 0;
	unsigned scratch_size = SI_CPDMA_ALIGNMENT * 2;

	assert(size < SI_CPDMA_ALIGNMENT);

	/* Use the scratch buffer as the dummy buffer. The 3D engine should be
	 * idle at this point.
	 */
	if (!sctx->scratch_buffer ||
	    sctx->scratch_buffer->b.b.width0 < scratch_size) {
		si_resource_reference(&sctx->scratch_buffer, NULL);
		sctx->scratch_buffer =
			si_aligned_buffer_create(&sctx->screen->b,
						   SI_RESOURCE_FLAG_UNMAPPABLE,
						   PIPE_USAGE_DEFAULT,
						   scratch_size, 256);
		if (!sctx->scratch_buffer)
			return;

		si_mark_atom_dirty(sctx, &sctx->atoms.s.scratch_state);
	}

	si_cp_dma_prepare(sctx, &sctx->scratch_buffer->b.b,
			  &sctx->scratch_buffer->b.b, size, size, user_flags,
			  coher, is_first, &dma_flags);

	va = sctx->scratch_buffer->gpu_address;
	si_emit_cp_dma(sctx, sctx->gfx_cs, va, va + SI_CPDMA_ALIGNMENT, size, dma_flags,
		       cache_policy);
}

/**
 * Do memcpy between buffers using CP DMA.
 * If src or dst is NULL, it means read or write GDS, respectively.
 *
 * \param user_flags	bitmask of SI_CPDMA_*
 */
void si_cp_dma_copy_buffer(struct si_context *sctx,
			   struct pipe_resource *dst, struct pipe_resource *src,
			   uint64_t dst_offset, uint64_t src_offset, unsigned size,
			   unsigned user_flags, enum si_coherency coher,
			   enum si_cache_policy cache_policy)
{
	uint64_t main_dst_offset, main_src_offset;
	unsigned skipped_size = 0;
	unsigned realign_size = 0;
	unsigned gds_flags = (dst ? 0 : CP_DMA_DST_IS_GDS) |
			     (src ? 0 : CP_DMA_SRC_IS_GDS);
	bool is_first = true;

	assert(size);

	if (dst) {
		/* Skip this for the L2 prefetch. */
		if (dst != src || dst_offset != src_offset) {
			/* Mark the buffer range of destination as valid (initialized),
			 * so that transfer_map knows it should wait for the GPU when mapping
			 * that range. */
			util_range_add(dst, &si_resource(dst)->valid_buffer_range, dst_offset,
				       dst_offset + size);
		}

		dst_offset += si_resource(dst)->gpu_address;
	}
	if (src)
		src_offset += si_resource(src)->gpu_address;

	/* The workarounds aren't needed on Fiji and beyond. */
	if (sctx->family <= CHIP_CARRIZO ||
	    sctx->family == CHIP_STONEY) {
		/* If the size is not aligned, we must add a dummy copy at the end
		 * just to align the internal counter. Otherwise, the DMA engine
		 * would slow down by an order of magnitude for following copies.
		 */
		if (size % SI_CPDMA_ALIGNMENT)
			realign_size = SI_CPDMA_ALIGNMENT - (size % SI_CPDMA_ALIGNMENT);

		/* If the copy begins unaligned, we must start copying from the next
		 * aligned block and the skipped part should be copied after everything
		 * else has been copied. Only the src alignment matters, not dst.
		 *
		 * GDS doesn't need the source address to be aligned.
		 */
		if (src && src_offset % SI_CPDMA_ALIGNMENT) {
			skipped_size = SI_CPDMA_ALIGNMENT - (src_offset % SI_CPDMA_ALIGNMENT);
			/* The main part will be skipped if the size is too small. */
			skipped_size = MIN2(skipped_size, size);
			size -= skipped_size;
		}
	}

	/* Flush the caches. */
	if ((dst || src) && !(user_flags & SI_CPDMA_SKIP_GFX_SYNC)) {
		sctx->flags |= SI_CONTEXT_PS_PARTIAL_FLUSH |
			       SI_CONTEXT_CS_PARTIAL_FLUSH |
			       si_get_flush_flags(sctx, coher, cache_policy);
	}

	/* This is the main part doing the copying. Src is always aligned. */
	main_dst_offset = dst_offset + skipped_size;
	main_src_offset = src_offset + skipped_size;

	while (size) {
		unsigned byte_count = MIN2(size, cp_dma_max_byte_count(sctx));
		unsigned dma_flags = gds_flags;

		si_cp_dma_prepare(sctx, dst, src, byte_count,
				  size + skipped_size + realign_size,
				  user_flags, coher, &is_first, &dma_flags);

		si_emit_cp_dma(sctx, sctx->gfx_cs, main_dst_offset, main_src_offset,
			       byte_count, dma_flags, cache_policy);

		size -= byte_count;
		main_src_offset += byte_count;
		main_dst_offset += byte_count;
	}

	/* Copy the part we skipped because src wasn't aligned. */
	if (skipped_size) {
		unsigned dma_flags = gds_flags;

		si_cp_dma_prepare(sctx, dst, src, skipped_size,
				  skipped_size + realign_size, user_flags,
				  coher, &is_first, &dma_flags);

		si_emit_cp_dma(sctx, sctx->gfx_cs, dst_offset, src_offset, skipped_size,
			       dma_flags, cache_policy);
	}

	/* Finally, realign the engine if the size wasn't aligned. */
	if (realign_size) {
		si_cp_dma_realign_engine(sctx, realign_size, user_flags, coher,
					 cache_policy, &is_first);
	}

	if (dst && cache_policy != L2_BYPASS)
		si_resource(dst)->TC_L2_dirty = true;

	/* If it's not a prefetch or GDS copy... */
	if (dst && src && (dst != src || dst_offset != src_offset)) {
		sctx->num_cp_dma_calls++;
		si_prim_discard_signal_next_compute_ib_start(sctx);
	}
}

void cik_prefetch_TC_L2_async(struct si_context *sctx, struct pipe_resource *buf,
			      uint64_t offset, unsigned size)
{
	assert(sctx->chip_class >= GFX7);

	si_cp_dma_copy_buffer(sctx, buf, buf, offset, offset, size,
			      SI_CPDMA_SKIP_ALL, SI_COHERENCY_SHADER, L2_LRU);
}

static void cik_prefetch_shader_async(struct si_context *sctx,
				      struct si_pm4_state *state)
{
	struct pipe_resource *bo = &state->bo[0]->b.b;
	assert(state->nbo == 1);

	cik_prefetch_TC_L2_async(sctx, bo, 0, bo->width0);
}

static void cik_prefetch_VBO_descriptors(struct si_context *sctx)
{
	if (!sctx->vertex_elements || !sctx->vertex_elements->desc_list_byte_size)
		return;

	cik_prefetch_TC_L2_async(sctx, &sctx->vb_descriptors_buffer->b.b,
				 sctx->vb_descriptors_offset,
				 sctx->vertex_elements->desc_list_byte_size);
}

/**
 * Prefetch shaders and VBO descriptors.
 *
 * \param vertex_stage_only  Whether only the the API VS and VBO descriptors
 *                           should be prefetched.
 */
void cik_emit_prefetch_L2(struct si_context *sctx, bool vertex_stage_only)
{
	unsigned mask = sctx->prefetch_L2_mask;
	assert(mask);

	/* Prefetch shaders and VBO descriptors to TC L2. */
	if (sctx->chip_class >= GFX9) {
		/* Choose the right spot for the VBO prefetch. */
		if (sctx->queued.named.hs) {
			if (mask & SI_PREFETCH_HS)
				cik_prefetch_shader_async(sctx, sctx->queued.named.hs);
			if (mask & SI_PREFETCH_VBO_DESCRIPTORS)
				cik_prefetch_VBO_descriptors(sctx);
			if (vertex_stage_only) {
				sctx->prefetch_L2_mask &= ~(SI_PREFETCH_HS |
							    SI_PREFETCH_VBO_DESCRIPTORS);
				return;
			}

			if (mask & SI_PREFETCH_GS)
				cik_prefetch_shader_async(sctx, sctx->queued.named.gs);
			if (mask & SI_PREFETCH_VS)
				cik_prefetch_shader_async(sctx, sctx->queued.named.vs);
		} else if (sctx->queued.named.gs) {
			if (mask & SI_PREFETCH_GS)
				cik_prefetch_shader_async(sctx, sctx->queued.named.gs);
			if (mask & SI_PREFETCH_VBO_DESCRIPTORS)
				cik_prefetch_VBO_descriptors(sctx);
			if (vertex_stage_only) {
				sctx->prefetch_L2_mask &= ~(SI_PREFETCH_GS |
							    SI_PREFETCH_VBO_DESCRIPTORS);
				return;
			}

			if (mask & SI_PREFETCH_VS)
				cik_prefetch_shader_async(sctx, sctx->queued.named.vs);
		} else {
			if (mask & SI_PREFETCH_VS)
				cik_prefetch_shader_async(sctx, sctx->queued.named.vs);
			if (mask & SI_PREFETCH_VBO_DESCRIPTORS)
				cik_prefetch_VBO_descriptors(sctx);
			if (vertex_stage_only) {
				sctx->prefetch_L2_mask &= ~(SI_PREFETCH_VS |
							    SI_PREFETCH_VBO_DESCRIPTORS);
				return;
			}
		}
	} else {
		/* GFX6-GFX8 */
		/* Choose the right spot for the VBO prefetch. */
		if (sctx->tes_shader.cso) {
			if (mask & SI_PREFETCH_LS)
				cik_prefetch_shader_async(sctx, sctx->queued.named.ls);
			if (mask & SI_PREFETCH_VBO_DESCRIPTORS)
				cik_prefetch_VBO_descriptors(sctx);
			if (vertex_stage_only) {
				sctx->prefetch_L2_mask &= ~(SI_PREFETCH_LS |
							    SI_PREFETCH_VBO_DESCRIPTORS);
				return;
			}

			if (mask & SI_PREFETCH_HS)
				cik_prefetch_shader_async(sctx, sctx->queued.named.hs);
			if (mask & SI_PREFETCH_ES)
				cik_prefetch_shader_async(sctx, sctx->queued.named.es);
			if (mask & SI_PREFETCH_GS)
				cik_prefetch_shader_async(sctx, sctx->queued.named.gs);
			if (mask & SI_PREFETCH_VS)
				cik_prefetch_shader_async(sctx, sctx->queued.named.vs);
		} else if (sctx->gs_shader.cso) {
			if (mask & SI_PREFETCH_ES)
				cik_prefetch_shader_async(sctx, sctx->queued.named.es);
			if (mask & SI_PREFETCH_VBO_DESCRIPTORS)
				cik_prefetch_VBO_descriptors(sctx);
			if (vertex_stage_only) {
				sctx->prefetch_L2_mask &= ~(SI_PREFETCH_ES |
							    SI_PREFETCH_VBO_DESCRIPTORS);
				return;
			}

			if (mask & SI_PREFETCH_GS)
				cik_prefetch_shader_async(sctx, sctx->queued.named.gs);
			if (mask & SI_PREFETCH_VS)
				cik_prefetch_shader_async(sctx, sctx->queued.named.vs);
		} else {
			if (mask & SI_PREFETCH_VS)
				cik_prefetch_shader_async(sctx, sctx->queued.named.vs);
			if (mask & SI_PREFETCH_VBO_DESCRIPTORS)
				cik_prefetch_VBO_descriptors(sctx);
			if (vertex_stage_only) {
				sctx->prefetch_L2_mask &= ~(SI_PREFETCH_VS |
							    SI_PREFETCH_VBO_DESCRIPTORS);
				return;
			}
		}
	}

	if (mask & SI_PREFETCH_PS)
		cik_prefetch_shader_async(sctx, sctx->queued.named.ps);

	sctx->prefetch_L2_mask = 0;
}

void si_test_gds(struct si_context *sctx)
{
	struct pipe_context *ctx = &sctx->b;
	struct pipe_resource *src, *dst;
	unsigned r[4] = {};
	unsigned offset = debug_get_num_option("OFFSET", 16);

	src = pipe_buffer_create(ctx->screen, 0, PIPE_USAGE_DEFAULT, 16);
	dst = pipe_buffer_create(ctx->screen, 0, PIPE_USAGE_DEFAULT, 16);
	si_cp_dma_clear_buffer(sctx, sctx->gfx_cs, src, 0, 4, 0xabcdef01, 0, SI_COHERENCY_SHADER, L2_BYPASS);
	si_cp_dma_clear_buffer(sctx, sctx->gfx_cs, src, 4, 4, 0x23456789, 0, SI_COHERENCY_SHADER, L2_BYPASS);
	si_cp_dma_clear_buffer(sctx, sctx->gfx_cs, src, 8, 4, 0x87654321, 0, SI_COHERENCY_SHADER, L2_BYPASS);
	si_cp_dma_clear_buffer(sctx, sctx->gfx_cs, src, 12, 4, 0xfedcba98, 0, SI_COHERENCY_SHADER, L2_BYPASS);
	si_cp_dma_clear_buffer(sctx, sctx->gfx_cs, dst, 0, 16, 0xdeadbeef, 0, SI_COHERENCY_SHADER, L2_BYPASS);

	si_cp_dma_copy_buffer(sctx, NULL, src, offset, 0, 16, 0, SI_COHERENCY_NONE, L2_BYPASS);
	si_cp_dma_copy_buffer(sctx, dst, NULL, 0, offset, 16, 0, SI_COHERENCY_NONE, L2_BYPASS);

	pipe_buffer_read(ctx, dst, 0, sizeof(r), r);
	printf("GDS copy  = %08x %08x %08x %08x -> %s\n", r[0], r[1], r[2], r[3],
			r[0] == 0xabcdef01 && r[1] == 0x23456789 &&
			r[2] == 0x87654321 && r[3] == 0xfedcba98 ? "pass" : "fail");

	si_cp_dma_clear_buffer(sctx, sctx->gfx_cs, NULL, offset, 16, 0xc1ea4146, 0, SI_COHERENCY_NONE, L2_BYPASS);
	si_cp_dma_copy_buffer(sctx, dst, NULL, 0, offset, 16, 0, SI_COHERENCY_NONE, L2_BYPASS);

	pipe_buffer_read(ctx, dst, 0, sizeof(r), r);
	printf("GDS clear = %08x %08x %08x %08x -> %s\n", r[0], r[1], r[2], r[3],
			r[0] == 0xc1ea4146 && r[1] == 0xc1ea4146 &&
			r[2] == 0xc1ea4146 && r[3] == 0xc1ea4146 ? "pass" : "fail");

	pipe_resource_reference(&src, NULL);
	pipe_resource_reference(&dst, NULL);
	exit(0);
}

void si_cp_write_data(struct si_context *sctx, struct si_resource *buf,
		      unsigned offset, unsigned size, unsigned dst_sel,
		      unsigned engine, const void *data)
{
	struct radeon_cmdbuf *cs = sctx->gfx_cs;

	assert(offset % 4 == 0);
	assert(size % 4 == 0);

	if (sctx->chip_class == GFX6 && dst_sel == V_370_MEM)
		dst_sel = V_370_MEM_GRBM;

	radeon_add_to_buffer_list(sctx, cs, buf,
				  RADEON_USAGE_WRITE, RADEON_PRIO_CP_DMA);
	uint64_t va = buf->gpu_address + offset;

	radeon_emit(cs, PKT3(PKT3_WRITE_DATA, 2 + size/4, 0));
	radeon_emit(cs, S_370_DST_SEL(dst_sel) |
		    S_370_WR_CONFIRM(1) |
		    S_370_ENGINE_SEL(engine));
	radeon_emit(cs, va);
	radeon_emit(cs, va >> 32);
	radeon_emit_array(cs, (const uint32_t*)data, size/4);
}

void si_cp_copy_data(struct si_context *sctx, struct radeon_cmdbuf *cs,
		     unsigned dst_sel, struct si_resource *dst, unsigned dst_offset,
		     unsigned src_sel, struct si_resource *src, unsigned src_offset)
{
	/* cs can point to the compute IB, which has the buffer list in gfx_cs. */
	if (dst) {
		radeon_add_to_buffer_list(sctx, sctx->gfx_cs, dst,
					  RADEON_USAGE_WRITE, RADEON_PRIO_CP_DMA);
	}
	if (src) {
		radeon_add_to_buffer_list(sctx, sctx->gfx_cs, src,
					  RADEON_USAGE_READ, RADEON_PRIO_CP_DMA);
	}

	uint64_t dst_va = (dst ? dst->gpu_address : 0ull) + dst_offset;
	uint64_t src_va = (src ? src->gpu_address : 0ull) + src_offset;

	radeon_emit(cs, PKT3(PKT3_COPY_DATA, 4, 0));
	radeon_emit(cs, COPY_DATA_SRC_SEL(src_sel) |
			COPY_DATA_DST_SEL(dst_sel) |
			COPY_DATA_WR_CONFIRM);
	radeon_emit(cs, src_va);
	radeon_emit(cs, src_va >> 32);
	radeon_emit(cs, dst_va);
	radeon_emit(cs, dst_va >> 32);
}