drm/amdgpu: Set a suitable dev_info.gart_page_size

In Mesa, dev_info.gart_page_size is used for alignment and it was
set to AMDGPU_GPU_PAGE_SIZE(4KB). However, the page table of AMDGPU
driver requires an alignment on CPU pages.  So, for non-4KB page system,
gart_page_size should be max_t(u32, PAGE_SIZE, AMDGPU_GPU_PAGE_SIZE).

Signed-off-by: Rui Wang <wangr@lemote.com>
Signed-off-by: Huacai Chen <chenhc@lemote.com>
Link: loongson-community/linux-stable@caa9c0a1
[Xi: rebased for drm-next, use max_t for checkpatch,
     and reworded commit message.]
Signed-off-by: Xi Ruoyao <xry111@mengyan1223.wang>
BugLink: https://gitlab.freedesktop.org/drm/amd/-/issues/1549
Tested-by: Dan Horák <dan@danny.cz>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c

@@ -778,9 +778,9 @@ int amdgpu_info_ioctl(struct drm_device *dev, void *data, struct drm_file *filp)
 			dev_info->high_va_offset = AMDGPU_GMC_HOLE_END;
 			dev_info->high_va_max = AMDGPU_GMC_HOLE_END | vm_size;
 		}
-		dev_info->virtual_address_alignment = max((int)PAGE_SIZE, AMDGPU_GPU_PAGE_SIZE);
+		dev_info->virtual_address_alignment = max_t(u32, PAGE_SIZE, AMDGPU_GPU_PAGE_SIZE);
 		dev_info->pte_fragment_size = (1 << adev->vm_manager.fragment_size) * AMDGPU_GPU_PAGE_SIZE;
-		dev_info->gart_page_size = AMDGPU_GPU_PAGE_SIZE;
+		dev_info->gart_page_size = max_t(u32, PAGE_SIZE, AMDGPU_GPU_PAGE_SIZE);
 		dev_info->cu_active_number = adev->gfx.cu_info.number;
 		dev_info->cu_ao_mask = adev->gfx.cu_info.ao_cu_mask;
 		dev_info->ce_ram_size = adev->gfx.ce_ram_size;