drm/amd/display: properly handling AGP aperture in vm setup

Take into account whether or not the AGP aperture is
enabled or not when calculating the system aperture.

Fixes white screens with DCN 3.1.4.

Based on a patch from Yifan Zhang <yifan1.zhang@amd.com>

Cc: Yifan Zhang <yifan1.zhang@amd.com>
Acked-by: Harry Wentland <harry.wentland@amd.com>
Reviewed-by: Yifan Zhang <yifan1.zhang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org # 6.1.x

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 78e047e1429c03d0e9443c1b48657c8e4af7c9bd..7f6e275618999abb2bc66e9eb8633d11b598a522 100644 (file)
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -1184,24 +1184,38 @@ static void mmhub_read_system_context(struct amdgpu_device *adev, struct dc_phy_
 
        memset(pa_config, 0, sizeof(*pa_config));
 
-       logical_addr_low  = min(adev->gmc.fb_start, adev->gmc.agp_start) >> 18;
-       pt_base = amdgpu_gmc_pd_addr(adev->gart.bo);
-
-       if (adev->apu_flags & AMD_APU_IS_RAVEN2)
-               /*
-                * Raven2 has a HW issue that it is unable to use the vram which
-                * is out of MC_VM_SYSTEM_APERTURE_HIGH_ADDR. So here is the
-                * workaround that increase system aperture high address (add 1)
-                * to get rid of the VM fault and hardware hang.
-                */
-               logical_addr_high = max((adev->gmc.fb_end >> 18) + 0x1, adev->gmc.agp_end >> 18);
-       else
-               logical_addr_high = max(adev->gmc.fb_end, adev->gmc.agp_end) >> 18;
-
        agp_base = 0;
        agp_bot = adev->gmc.agp_start >> 24;
        agp_top = adev->gmc.agp_end >> 24;
 
+       /* AGP aperture is disabled */
+       if (agp_bot == agp_top) {
+               logical_addr_low  = adev->gmc.vram_start >> 18;
+               if (adev->apu_flags & AMD_APU_IS_RAVEN2)
+                       /*
+                        * Raven2 has a HW issue that it is unable to use the vram which
+                        * is out of MC_VM_SYSTEM_APERTURE_HIGH_ADDR. So here is the
+                        * workaround that increase system aperture high address (add 1)
+                        * to get rid of the VM fault and hardware hang.
+                        */
+                       logical_addr_high = (adev->gmc.fb_end >> 18) + 0x1;
+               else
+                       logical_addr_high = adev->gmc.vram_end >> 18;
+       } else {
+               logical_addr_low  = min(adev->gmc.fb_start, adev->gmc.agp_start) >> 18;
+               if (adev->apu_flags & AMD_APU_IS_RAVEN2)
+                       /*
+                        * Raven2 has a HW issue that it is unable to use the vram which
+                        * is out of MC_VM_SYSTEM_APERTURE_HIGH_ADDR. So here is the
+                        * workaround that increase system aperture high address (add 1)
+                        * to get rid of the VM fault and hardware hang.
+                        */
+                       logical_addr_high = max((adev->gmc.fb_end >> 18) + 0x1, adev->gmc.agp_end >> 18);
+               else
+                       logical_addr_high = max(adev->gmc.fb_end, adev->gmc.agp_end) >> 18;
+       }
+
+       pt_base = amdgpu_gmc_pd_addr(adev->gart.bo);
 
        page_table_start.high_part = (u32)(adev->gmc.gart_start >> 44) & 0xF;
        page_table_start.low_part = (u32)(adev->gmc.gart_start >> 12);