github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-05-21 05:18:45 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

drm/amdgpu/vcn5.0.1: read back register after written

Browse Source 
The addition of register read-back in VCN v5.0.1 is intended to prevent
potential race conditions.

Reviewed-by: Ruijing Dong <ruijing.dong@amd.com>
Signed-off-by: David (Ming Qiang) Wu <David.Wu3@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
This commit is contained in:
David (Ming Qiang) Wu 2025-05-14 18:59:11 -04:00 committed by Alex Deucher
parent a8bce9b7a2
commit bf394d2854
1 changed files with 15 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

15
drivers/gpu/drm/amd/amdgpu/vcn_v5_0_1.c
View File

@ -1038,6 +1038,11 @@ static int vcn_v5_0_1_start(struct amdgpu_vcn_inst *vinst)
WREG32_SOC15(VCN, vcn_inst, regVCN_RB_ENABLE, tmp);
fw_shared->sq.queue_mode &= ~(FW_QUEUE_RING_RESET | FW_QUEUE_DPG_HOLD_OFF);
/* Keeping one read-back to ensure all register writes are done,
* otherwise it may introduce race conditions.
*/
RREG32_SOC15(VCN, vcn_inst, regUVD_STATUS);
return 0;
}
@ -1072,6 +1077,11 @@ static void vcn_v5_0_1_stop_dpg_mode(struct amdgpu_vcn_inst *vinst)
/* disable dynamic power gating mode */
WREG32_P(SOC15_REG_OFFSET(VCN, vcn_inst, regUVD_POWER_STATUS), 0,
~UVD_POWER_STATUS__UVD_PG_MODE_MASK);
/* Keeping one read-back to ensure all register writes are done,
* otherwise it may introduce race conditions.
*/
RREG32_SOC15(VCN, vcn_inst, regUVD_STATUS);
}
/**
@ -1147,6 +1157,11 @@ static int vcn_v5_0_1_stop(struct amdgpu_vcn_inst *vinst)
/* clear status */
WREG32_SOC15(VCN, vcn_inst, regUVD_STATUS, 0);
/* Keeping one read-back to ensure all register writes are done,
* otherwise it may introduce race conditions.
*/
RREG32_SOC15(VCN, vcn_inst, regUVD_STATUS);
return 0;
}