From: Victor Zhao Victor.Zhao@amd.com

[ Upstream commit 2370eba9f552eaae3d8aa1f70b8e9eec5c560f9e ]

[Why] When some tools performing psp mailbox attack, the readback value of register can be a random value which may break psp.

[How] Use a psp wptr cache machanism to aovid the change made by attack.

v2: unify change and add detailed reason

Signed-off-by: Victor Zhao Victor.Zhao@amd.com Signed-off-by: Jingwen Chen Jingwen.Chen2@amd.com Reviewed-by: Monk Liu monk.liu@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/amd/amdgpu/amdgpu_psp.h | 1 + drivers/gpu/drm/amd/amdgpu/psp_v11_0.c | 3 ++- drivers/gpu/drm/amd/amdgpu/psp_v3_1.c | 3 ++- 3 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_psp.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_psp.h index cb50ba445f8c..0fd62a8e68c2 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_psp.h +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_psp.h @@ -76,6 +76,7 @@ struct psp_ring uint64_t ring_mem_mc_addr; void *ring_mem_handle; uint32_t ring_size; + uint32_t ring_wptr; };

/* More registers may will be supported */ diff --git a/drivers/gpu/drm/amd/amdgpu/psp_v11_0.c b/drivers/gpu/drm/amd/amdgpu/psp_v11_0.c index c325d6f53a71..d39735a89a25 100644 --- a/drivers/gpu/drm/amd/amdgpu/psp_v11_0.c +++ b/drivers/gpu/drm/amd/amdgpu/psp_v11_0.c @@ -720,7 +720,7 @@ static uint32_t psp_v11_0_ring_get_wptr(struct psp_context *psp) struct amdgpu_device *adev = psp->adev;

if (amdgpu_sriov_vf(adev)) - data = RREG32_SOC15(MP0, 0, mmMP0_SMN_C2PMSG_102); + data = psp->km_ring.ring_wptr; else data = RREG32_SOC15(MP0, 0, mmMP0_SMN_C2PMSG_67);

@@ -734,6 +734,7 @@ static void psp_v11_0_ring_set_wptr(struct psp_context *psp, uint32_t value) if (amdgpu_sriov_vf(adev)) { WREG32_SOC15(MP0, 0, mmMP0_SMN_C2PMSG_102, value); WREG32_SOC15(MP0, 0, mmMP0_SMN_C2PMSG_101, GFX_CTRL_CMD_ID_CONSUME_CMD); + psp->km_ring.ring_wptr = value; } else WREG32_SOC15(MP0, 0, mmMP0_SMN_C2PMSG_67, value); } diff --git a/drivers/gpu/drm/amd/amdgpu/psp_v3_1.c b/drivers/gpu/drm/amd/amdgpu/psp_v3_1.c index f2e725f72d2f..908664a5774b 100644 --- a/drivers/gpu/drm/amd/amdgpu/psp_v3_1.c +++ b/drivers/gpu/drm/amd/amdgpu/psp_v3_1.c @@ -379,7 +379,7 @@ static uint32_t psp_v3_1_ring_get_wptr(struct psp_context *psp) struct amdgpu_device *adev = psp->adev;

if (amdgpu_sriov_vf(adev)) - data = RREG32_SOC15(MP0, 0, mmMP0_SMN_C2PMSG_102); + data = psp->km_ring.ring_wptr; else data = RREG32_SOC15(MP0, 0, mmMP0_SMN_C2PMSG_67); return data; @@ -394,6 +394,7 @@ static void psp_v3_1_ring_set_wptr(struct psp_context *psp, uint32_t value) /* send interrupt to PSP for SRIOV ring write pointer update */ WREG32_SOC15(MP0, 0, mmMP0_SMN_C2PMSG_101, GFX_CTRL_CMD_ID_CONSUME_CMD); + psp->km_ring.ring_wptr = value; } else WREG32_SOC15(MP0, 0, mmMP0_SMN_C2PMSG_67, value); }