[PATCH 1/3] drm/amdgpu/gmc6-8: properly disable the AGP aperture

Alex Deucher alexander.deucher at amd.com
Wed Sep 20 17:46:04 UTC 2023


The BOT register needs to be larger than the TOP register
for this to be properly disabled.  The lower 22 bits
of the BOT address are always 0 and the lower 22 bits of
the TOP register are always 1 so you need to make
the upper bits of BOT larger than the upper bits of BOT.

Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/gmc_v6_0.c | 2 +-
 drivers/gpu/drm/amd/amdgpu/gmc_v7_0.c | 2 +-
 drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/gmc_v6_0.c b/drivers/gpu/drm/amd/amdgpu/gmc_v6_0.c
index 5b837a65fad2..07579fa26fa3 100644
--- a/drivers/gpu/drm/amd/amdgpu/gmc_v6_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/gmc_v6_0.c
@@ -253,7 +253,7 @@ static void gmc_v6_0_mc_program(struct amdgpu_device *adev)
 	WREG32(mmMC_VM_SYSTEM_APERTURE_DEFAULT_ADDR,
 	       adev->mem_scratch.gpu_addr >> 12);
 	WREG32(mmMC_VM_AGP_BASE, 0);
-	WREG32(mmMC_VM_AGP_TOP, 0x0FFFFFFF);
+	WREG32(mmMC_VM_AGP_TOP, 0);
 	WREG32(mmMC_VM_AGP_BOT, 0x0FFFFFFF);
 
 	if (gmc_v6_0_wait_for_idle((void *)adev))
diff --git a/drivers/gpu/drm/amd/amdgpu/gmc_v7_0.c b/drivers/gpu/drm/amd/amdgpu/gmc_v7_0.c
index 6a6929ac2748..e77e5593e1ab 100644
--- a/drivers/gpu/drm/amd/amdgpu/gmc_v7_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/gmc_v7_0.c
@@ -288,7 +288,7 @@ static void gmc_v7_0_mc_program(struct amdgpu_device *adev)
 	WREG32(mmMC_VM_SYSTEM_APERTURE_DEFAULT_ADDR,
 	       adev->mem_scratch.gpu_addr >> 12);
 	WREG32(mmMC_VM_AGP_BASE, 0);
-	WREG32(mmMC_VM_AGP_TOP, 0x0FFFFFFF);
+	WREG32(mmMC_VM_AGP_TOP, 0);
 	WREG32(mmMC_VM_AGP_BOT, 0x0FFFFFFF);
 	if (gmc_v7_0_wait_for_idle((void *)adev))
 		dev_warn(adev->dev, "Wait for MC idle timedout !\n");
diff --git a/drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c b/drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c
index 5af235202513..6acf649469dd 100644
--- a/drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c
@@ -473,7 +473,7 @@ static void gmc_v8_0_mc_program(struct amdgpu_device *adev)
 	}
 
 	WREG32(mmMC_VM_AGP_BASE, 0);
-	WREG32(mmMC_VM_AGP_TOP, 0x0FFFFFFF);
+	WREG32(mmMC_VM_AGP_TOP, 0);
 	WREG32(mmMC_VM_AGP_BOT, 0x0FFFFFFF);
 	if (gmc_v8_0_wait_for_idle((void *)adev))
 		dev_warn(adev->dev, "Wait for MC idle timedout !\n");
-- 
2.41.0



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