drm/amd/amdgpu:save psp ring wptr to avoid attack

[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>
This commit is contained in:
Victor Zhao 2021-03-18 13:44:35 +08:00 committed by Alex Deucher
parent c5699e2d86
commit 2370eba9f5
3 changed files with 5 additions and 2 deletions

View file

@ -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 */

View file

@ -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);
}

View file

@ -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);
}