[v3 5/7] drm/amdgpu: Optimize SDMA v5.2 queue reset and stop logic
Alex Deucher
alexdeucher at gmail.com
Mon Apr 7 20:05:22 UTC 2025
On Wed, Apr 2, 2025 at 5:15 AM Jesse.zhang at amd.com <jesse.zhang at amd.com> wrote:
>
> From: "Jesse.zhang at amd.com" <Jesse.zhang at amd.com>
>
> This patch refactors the SDMA v5.2 queue reset and stop logic to improve
> code readability, maintainability, and performance. The key changes include:
>
> 1. **Generalized `sdma_v5_2_gfx_stop` Function**:
> - Added an `inst_mask` parameter to allow stopping specific SDMA instances
> instead of all instances. This is useful for resetting individual queues.
>
> 2. **Simplified `sdma_v5_2_reset_queue` Function**:
> - Removed redundant loops and checks by directly using the `ring->me` field
> to identify the SDMA instance.
> - Reused the `sdma_v5_2_gfx_stop` function to stop the queue, reducing code
> duplication.
>
> Signed-off-by: Jesse Zhang <jesse.zhang at amd.com>
Acked-by: Alex Deucher <alexander.deucher at amd.com>
> ---
> drivers/gpu/drm/amd/amdgpu/sdma_v5_2.c | 64 +++++++++++---------------
> 1 file changed, 26 insertions(+), 38 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/sdma_v5_2.c b/drivers/gpu/drm/amd/amdgpu/sdma_v5_2.c
> index 964f12afac9e..96b02c3e4993 100644
> --- a/drivers/gpu/drm/amd/amdgpu/sdma_v5_2.c
> +++ b/drivers/gpu/drm/amd/amdgpu/sdma_v5_2.c
> @@ -405,15 +405,15 @@ static void sdma_v5_2_ring_emit_fence(struct amdgpu_ring *ring, u64 addr, u64 se
> * sdma_v5_2_gfx_stop - stop the gfx async dma engines
> *
> * @adev: amdgpu_device pointer
> - *
> + * @inst_mask: mask of dma engine instances to be disabled
> * Stop the gfx async dma ring buffers.
> */
> -static void sdma_v5_2_gfx_stop(struct amdgpu_device *adev)
> +static void sdma_v5_2_gfx_stop(struct amdgpu_device *adev, uint32_t inst_mask)
> {
> u32 rb_cntl, ib_cntl;
> int i;
>
> - for (i = 0; i < adev->sdma.num_instances; i++) {
> + for_each_inst(i, inst_mask) {
> rb_cntl = RREG32_SOC15_IP(GC, sdma_v5_2_get_reg_offset(adev, i, mmSDMA0_GFX_RB_CNTL));
> rb_cntl = REG_SET_FIELD(rb_cntl, SDMA0_GFX_RB_CNTL, RB_ENABLE, 0);
> WREG32_SOC15_IP(GC, sdma_v5_2_get_reg_offset(adev, i, mmSDMA0_GFX_RB_CNTL), rb_cntl);
> @@ -504,9 +504,11 @@ static void sdma_v5_2_enable(struct amdgpu_device *adev, bool enable)
> {
> u32 f32_cntl;
> int i;
> + uint32_t inst_mask;
>
> + inst_mask = GENMASK(adev->sdma.num_instances - 1, 0);
> if (!enable) {
> - sdma_v5_2_gfx_stop(adev);
> + sdma_v5_2_gfx_stop(adev, inst_mask);
> sdma_v5_2_rlc_stop(adev);
> }
>
> @@ -1437,40 +1439,26 @@ static int sdma_v5_2_wait_for_idle(struct amdgpu_ip_block *ip_block)
> static int sdma_v5_2_reset_queue(struct amdgpu_ring *ring, unsigned int vmid)
> {
> struct amdgpu_device *adev = ring->adev;
> - int i, j, r;
> - u32 rb_cntl, ib_cntl, f32_cntl, freeze, cntl, preempt, soft_reset, stat1_reg;
> + int j, r;
> + u32 f32_cntl, freeze, cntl, preempt, soft_reset, stat1_reg;
> + u32 inst_id;
>
> if (amdgpu_sriov_vf(adev))
> return -EINVAL;
>
> - for (i = 0; i < adev->sdma.num_instances; i++) {
> - if (ring == &adev->sdma.instance[i].ring)
> - break;
> - }
> -
> - if (i == adev->sdma.num_instances) {
> - DRM_ERROR("sdma instance not found\n");
> - return -EINVAL;
> - }
> -
> + inst_id = ring->me;
> amdgpu_gfx_rlc_enter_safe_mode(adev, 0);
>
> /* stop queue */
> - ib_cntl = RREG32(sdma_v5_2_get_reg_offset(adev, i, mmSDMA0_GFX_IB_CNTL));
> - ib_cntl = REG_SET_FIELD(ib_cntl, SDMA0_GFX_IB_CNTL, IB_ENABLE, 0);
> - WREG32(sdma_v5_2_get_reg_offset(adev, i, mmSDMA0_GFX_IB_CNTL), ib_cntl);
> -
> - rb_cntl = RREG32(sdma_v5_2_get_reg_offset(adev, i, mmSDMA0_GFX_RB_CNTL));
> - rb_cntl = REG_SET_FIELD(rb_cntl, SDMA0_GFX_RB_CNTL, RB_ENABLE, 0);
> - WREG32(sdma_v5_2_get_reg_offset(adev, i, mmSDMA0_GFX_RB_CNTL), rb_cntl);
> + sdma_v5_2_gfx_stop(adev, 1 << ring->me);
>
> /*engine stop SDMA1_F32_CNTL.HALT to 1 and SDMAx_FREEZE freeze bit to 1 */
> - freeze = RREG32(sdma_v5_2_get_reg_offset(adev, i, mmSDMA0_FREEZE));
> + freeze = RREG32(sdma_v5_2_get_reg_offset(adev, inst_id, mmSDMA0_FREEZE));
> freeze = REG_SET_FIELD(freeze, SDMA0_FREEZE, FREEZE, 1);
> - WREG32(sdma_v5_2_get_reg_offset(adev, i, mmSDMA0_FREEZE), freeze);
> + WREG32(sdma_v5_2_get_reg_offset(adev, inst_id, mmSDMA0_FREEZE), freeze);
>
> for (j = 0; j < adev->usec_timeout; j++) {
> - freeze = RREG32(sdma_v5_2_get_reg_offset(adev, i, mmSDMA0_FREEZE));
> + freeze = RREG32(sdma_v5_2_get_reg_offset(adev, inst_id, mmSDMA0_FREEZE));
>
> if (REG_GET_FIELD(freeze, SDMA0_FREEZE, FROZEN) & 1)
> break;
> @@ -1479,7 +1467,7 @@ static int sdma_v5_2_reset_queue(struct amdgpu_ring *ring, unsigned int vmid)
>
>
> if (j == adev->usec_timeout) {
> - stat1_reg = RREG32(sdma_v5_2_get_reg_offset(adev, i, mmSDMA0_STATUS1_REG));
> + stat1_reg = RREG32(sdma_v5_2_get_reg_offset(adev, inst_id, mmSDMA0_STATUS1_REG));
> if ((stat1_reg & 0x3FF) != 0x3FF) {
> DRM_ERROR("cannot soft reset as sdma not idle\n");
> r = -ETIMEDOUT;
> @@ -1487,37 +1475,37 @@ static int sdma_v5_2_reset_queue(struct amdgpu_ring *ring, unsigned int vmid)
> }
> }
>
> - f32_cntl = RREG32(sdma_v5_2_get_reg_offset(adev, i, mmSDMA0_F32_CNTL));
> + f32_cntl = RREG32(sdma_v5_2_get_reg_offset(adev, inst_id, mmSDMA0_F32_CNTL));
> f32_cntl = REG_SET_FIELD(f32_cntl, SDMA0_F32_CNTL, HALT, 1);
> - WREG32(sdma_v5_2_get_reg_offset(adev, i, mmSDMA0_F32_CNTL), f32_cntl);
> + WREG32(sdma_v5_2_get_reg_offset(adev, inst_id, mmSDMA0_F32_CNTL), f32_cntl);
>
> - cntl = RREG32(sdma_v5_2_get_reg_offset(adev, i, mmSDMA0_CNTL));
> + cntl = RREG32(sdma_v5_2_get_reg_offset(adev, inst_id, mmSDMA0_CNTL));
> cntl = REG_SET_FIELD(cntl, SDMA0_CNTL, UTC_L1_ENABLE, 0);
> - WREG32(sdma_v5_2_get_reg_offset(adev, i, mmSDMA0_CNTL), cntl);
> + WREG32(sdma_v5_2_get_reg_offset(adev, inst_id, mmSDMA0_CNTL), cntl);
>
> /* soft reset SDMA_GFX_PREEMPT.IB_PREEMPT = 0 mmGRBM_SOFT_RESET.SOFT_RESET_SDMA0/1 = 1 */
> - preempt = RREG32(sdma_v5_2_get_reg_offset(adev, i, mmSDMA0_GFX_PREEMPT));
> + preempt = RREG32(sdma_v5_2_get_reg_offset(adev, inst_id, mmSDMA0_GFX_PREEMPT));
> preempt = REG_SET_FIELD(preempt, SDMA0_GFX_PREEMPT, IB_PREEMPT, 0);
> - WREG32(sdma_v5_2_get_reg_offset(adev, i, mmSDMA0_GFX_PREEMPT), preempt);
> + WREG32(sdma_v5_2_get_reg_offset(adev, inst_id, mmSDMA0_GFX_PREEMPT), preempt);
>
> soft_reset = RREG32_SOC15(GC, 0, mmGRBM_SOFT_RESET);
> - soft_reset |= 1 << GRBM_SOFT_RESET__SOFT_RESET_SDMA0__SHIFT << i;
> + soft_reset |= 1 << GRBM_SOFT_RESET__SOFT_RESET_SDMA0__SHIFT << inst_id;
>
>
> WREG32_SOC15(GC, 0, mmGRBM_SOFT_RESET, soft_reset);
>
> udelay(50);
>
> - soft_reset &= ~(1 << GRBM_SOFT_RESET__SOFT_RESET_SDMA0__SHIFT << i);
> + soft_reset &= ~(1 << GRBM_SOFT_RESET__SOFT_RESET_SDMA0__SHIFT << inst_id);
>
> WREG32_SOC15(GC, 0, mmGRBM_SOFT_RESET, soft_reset);
>
> /* unfreeze and unhalt */
> - freeze = RREG32(sdma_v5_2_get_reg_offset(adev, i, mmSDMA0_FREEZE));
> + freeze = RREG32(sdma_v5_2_get_reg_offset(adev, inst_id, mmSDMA0_FREEZE));
> freeze = REG_SET_FIELD(freeze, SDMA0_FREEZE, FREEZE, 0);
> - WREG32(sdma_v5_2_get_reg_offset(adev, i, mmSDMA0_FREEZE), freeze);
> + WREG32(sdma_v5_2_get_reg_offset(adev, inst_id, mmSDMA0_FREEZE), freeze);
>
> - r = sdma_v5_2_gfx_resume_instance(adev, i, true);
> + r = sdma_v5_2_gfx_resume_instance(adev, inst_id, true);
>
> err0:
> amdgpu_gfx_rlc_exit_safe_mode(adev, 0);
> --
> 2.25.1
>
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