COND_EXEC tells the CP to discard the dwords following it when its condition is zero (false).
This is useful for GPU recovery because it can help reduce collateral damage during GFX IP block soft reset, meaning that it reduces the likelyhood that we fail some jobs which are not guilty of the hang as the IP block soft reset mechanism clears the condition before doing the reset. Signed-off-by: Timur Kristóf <[email protected]> --- drivers/gpu/drm/amd/amdgpu/gfx_v7_0.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) diff --git a/drivers/gpu/drm/amd/amdgpu/gfx_v7_0.c b/drivers/gpu/drm/amd/amdgpu/gfx_v7_0.c index 915612628f9a..6d52b8710437 100644 --- a/drivers/gpu/drm/amd/amdgpu/gfx_v7_0.c +++ b/drivers/gpu/drm/amd/amdgpu/gfx_v7_0.c @@ -3162,6 +3162,22 @@ static void gfx_v7_0_ring_emit_vm_flush(struct amdgpu_ring *ring, } } +static unsigned int gfx_v7_0_ring_emit_init_cond_exec(struct amdgpu_ring *ring, + uint64_t gpu_addr) +{ + unsigned int ret; + + /* Discard following DWs after this packet when gpu_addr==0 */ + amdgpu_ring_write(ring, PACKET3(PACKET3_COND_EXEC, 3)); + amdgpu_ring_write(ring, lower_32_bits(gpu_addr)); + amdgpu_ring_write(ring, upper_32_bits(gpu_addr)); + amdgpu_ring_write(ring, 0); + ret = ring->wptr & ring->buf_mask; + /* patch dummy value later */ + amdgpu_ring_write(ring, 0); + return ret; +} + static void gfx_v7_0_ring_emit_wreg(struct amdgpu_ring *ring, uint32_t reg, uint32_t val) { @@ -4943,6 +4959,8 @@ static const struct amdgpu_ring_funcs gfx_v7_0_ring_funcs_gfx = { .get_wptr = gfx_v7_0_ring_get_wptr_gfx, .set_wptr = gfx_v7_0_ring_set_wptr_gfx, .emit_frame_size = + 5 + /* gfx_v7_0_ring_emit_init_cond_exec (from amdgpu_ib_schedule) */ + 5 + /* gfx_v7_0_ring_emit_init_cond_exec (from amdgpu_vm_flush) */ 20 + /* gfx_v7_0_ring_emit_gds_switch */ 7 + /* gfx_v7_0_ring_emit_hdp_flush */ 5 + /* hdp invalidate */ @@ -4965,6 +4983,7 @@ static const struct amdgpu_ring_funcs gfx_v7_0_ring_funcs_gfx = { .pad_ib = amdgpu_ring_generic_pad_ib, .emit_switch_buffer = gfx_v7_0_ring_emit_sb, .emit_cntxcntl = gfx_v7_ring_emit_cntxcntl, + .init_cond_exec = gfx_v7_0_ring_emit_init_cond_exec, .emit_wreg = gfx_v7_0_ring_emit_wreg, .soft_recovery = gfx_v7_0_ring_soft_recovery, .emit_mem_sync = gfx_v7_0_emit_mem_sync, @@ -4979,6 +4998,8 @@ static const struct amdgpu_ring_funcs gfx_v7_0_ring_funcs_compute = { .get_wptr = gfx_v7_0_ring_get_wptr_compute, .set_wptr = gfx_v7_0_ring_set_wptr_compute, .emit_frame_size = + 5 + /* gfx_v7_0_ring_emit_init_cond_exec (from amdgpu_ib_schedule) */ + 5 + /* gfx_v7_0_ring_emit_init_cond_exec (from amdgpu_vm_flush) */ 20 + /* gfx_v7_0_ring_emit_gds_switch */ 7 + /* gfx_v7_0_ring_emit_hdp_flush */ 5 + /* hdp invalidate */ @@ -4997,6 +5018,7 @@ static const struct amdgpu_ring_funcs gfx_v7_0_ring_funcs_compute = { .test_ib = gfx_v7_0_ring_test_ib, .insert_nop = amdgpu_ring_insert_nop, .pad_ib = amdgpu_ring_generic_pad_ib, + .init_cond_exec = gfx_v7_0_ring_emit_init_cond_exec, .emit_wreg = gfx_v7_0_ring_emit_wreg, .soft_recovery = gfx_v7_0_ring_soft_recovery, .emit_mem_sync = gfx_v7_0_emit_mem_sync_compute, -- 2.55.0
