[PATCH 3/4] drm/amdgpu/vcn2.0: stall DPG when WPTR/RPTR reset

[James Zhu]

Add vcn dpg harware and firmware synchronization to fix race condition
issue among vcn driver, hardware and firmware

Signed-off-by: James Zhu <James.Zhu at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/vcn_v2_0.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/vcn_v2_0.c b/drivers/gpu/drm/amd/amdgpu/vcn_v2_0.c
index c387c81..7719f56 100644
--- a/drivers/gpu/drm/amd/amdgpu/vcn_v2_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/vcn_v2_0.c
@@ -1158,8 +1158,12 @@ static int vcn_v2_0_pause_dpg_mode(struct amdgpu_device *adev,
 					   UVD_DPG_PAUSE__NJ_PAUSE_DPG_ACK_MASK,
 					   UVD_DPG_PAUSE__NJ_PAUSE_DPG_ACK_MASK, ret_code);
 
+
+				/* Stall DPG before WPTR/RPTR reset */
+				WREG32_P(SOC15_REG_OFFSET(UVD, 0, mmUVD_POWER_STATUS), UVD_POWER_STATUS__STALL_DPG_POWER_UP_MASK, ~UVD_POWER_STATUS__STALL_DPG_POWER_UP_MASK);
 				/* Restore */
 				ring = &adev->vcn.inst->ring_enc[0];
+				ring->wptr = 0;
 				WREG32_SOC15(UVD, 0, mmUVD_RB_BASE_LO, ring->gpu_addr);
 				WREG32_SOC15(UVD, 0, mmUVD_RB_BASE_HI, upper_32_bits(ring->gpu_addr));
 				WREG32_SOC15(UVD, 0, mmUVD_RB_SIZE, ring->ring_size / 4);
@@ -1167,6 +1171,7 @@ static int vcn_v2_0_pause_dpg_mode(struct amdgpu_device *adev,
 				WREG32_SOC15(UVD, 0, mmUVD_RB_WPTR, lower_32_bits(ring->wptr));
 
 				ring = &adev->vcn.inst->ring_enc[1];
+				ring->wptr = 0;
 				WREG32_SOC15(UVD, 0, mmUVD_RB_BASE_LO2, ring->gpu_addr);
 				WREG32_SOC15(UVD, 0, mmUVD_RB_BASE_HI2, upper_32_bits(ring->gpu_addr));
 				WREG32_SOC15(UVD, 0, mmUVD_RB_SIZE2, ring->ring_size / 4);
@@ -1175,6 +1180,8 @@ static int vcn_v2_0_pause_dpg_mode(struct amdgpu_device *adev,
 
 				WREG32_SOC15(UVD, 0, mmUVD_RBC_RB_WPTR,
 					   RREG32_SOC15(UVD, 0, mmUVD_SCRATCH2) & 0x7FFFFFFF);
+				/* Unstall DPG */
+				WREG32_P(SOC15_REG_OFFSET(UVD, 0, mmUVD_POWER_STATUS), 0, ~UVD_POWER_STATUS__STALL_DPG_POWER_UP_MASK);
 
 				SOC15_WAIT_ON_RREG(UVD, 0, mmUVD_POWER_STATUS,
 					   UVD_PGFSM_CONFIG__UVDM_UVDU_PWR_ON,
-- 
2.7.4