From 2d251f17a85e259a430a9c0ddef0734e55109f76 Mon Sep 17 00:00:00 2001 From: Bokun Zhang Date: Mon, 9 Nov 2020 13:59:27 -0500 Subject: [PATCH] drm/amd/amdgpu: Fix incorrect logic to increment VCN doorbell index - The original logic uses a counter based index assignment, which is incorrect if we only assign VCN1 to this VF but no VCN0 The doorbell index is absolute, so we can calculate it by using index variable i and j Signed-off-by: Bokun Zhang Reviewed-by: Monk Liu Signed-off-by: Alex Deucher --- drivers/gpu/drm/amd/amdgpu/vcn_v3_0.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/vcn_v3_0.c b/drivers/gpu/drm/amd/amdgpu/vcn_v3_0.c index 269002816109b..3970a0ccb6a57 100644 --- a/drivers/gpu/drm/amd/amdgpu/vcn_v3_0.c +++ b/drivers/gpu/drm/amd/amdgpu/vcn_v3_0.c @@ -155,6 +155,13 @@ static int vcn_v3_0_sw_init(void *handle) if (r) return r; + /* + * Note: doorbell assignment is fixed for SRIOV multiple VCN engines + * Formula: + * vcn_db_base = adev->doorbell_index.vcn.vcn_ring0_1 << 1; + * dec_ring_i = vcn_db_base + i * (adev->vcn.num_enc_rings + 1) + * enc_ring_i,j = vcn_db_base + i * (adev->vcn.num_enc_rings + 1) + 1 + j + */ if (amdgpu_sriov_vf(adev)) { vcn_doorbell_index = adev->doorbell_index.vcn.vcn_ring0_1; /* get DWORD offset */ @@ -192,9 +199,7 @@ static int vcn_v3_0_sw_init(void *handle) ring = &adev->vcn.inst[i].ring_dec; ring->use_doorbell = true; if (amdgpu_sriov_vf(adev)) { - ring->doorbell_index = vcn_doorbell_index; - /* NOTE: increment so next VCN engine use next DOORBELL DWORD */ - vcn_doorbell_index++; + ring->doorbell_index = vcn_doorbell_index + i * (adev->vcn.num_enc_rings + 1); } else { ring->doorbell_index = (adev->doorbell_index.vcn.vcn_ring0_1 << 1) + 8 * i; } @@ -216,9 +221,7 @@ static int vcn_v3_0_sw_init(void *handle) ring = &adev->vcn.inst[i].ring_enc[j]; ring->use_doorbell = true; if (amdgpu_sriov_vf(adev)) { - ring->doorbell_index = vcn_doorbell_index; - /* NOTE: increment so next VCN engine use next DOORBELL DWORD */ - vcn_doorbell_index++; + ring->doorbell_index = vcn_doorbell_index + i * (adev->vcn.num_enc_rings + 1) + 1 + j; } else { ring->doorbell_index = (adev->doorbell_index.vcn.vcn_ring0_1 << 1) + 2 + j + 8 * i; } -- 2.39.5