drm/amdgpu: access stolen VRAM directly on CZ (v2)

We don't need to use the PCI BAR on APUs. This allows us to access
the full VRAM directly without being limited by the BAR size.

v2: squash in 64bit shift fix

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c b/drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c
index 684a5f34d60dc4b275b2db54bc6b11cbf3fe9c5e..7669b3259f35e23dab22352b5deb3ffdf4631491 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c
@@ -467,9 +467,16 @@ static int gmc_v8_0_mc_init(struct amdgpu_device *adev)
        /* size in MB on si */
        adev->mc.mc_vram_size = RREG32(mmCONFIG_MEMSIZE) * 1024ULL * 1024ULL;
        adev->mc.real_vram_size = RREG32(mmCONFIG_MEMSIZE) * 1024ULL * 1024ULL;
-       adev->mc.visible_vram_size = adev->mc.aper_size;
+
+#ifdef CONFIG_X86_64
+       if (adev->flags & AMD_IS_APU) {
+               adev->mc.aper_base = ((u64)RREG32(mmMC_VM_FB_OFFSET)) << 22;
+               adev->mc.aper_size = adev->mc.real_vram_size;
+       }
+#endif
 
        /* In case the PCI BAR is larger than the actual amount of vram */
+       adev->mc.visible_vram_size = adev->mc.aper_size;
        if (adev->mc.visible_vram_size > adev->mc.real_vram_size)
                adev->mc.visible_vram_size = adev->mc.real_vram_size;