[PATCH] drm/amdgpu: Fix CSA buffer alloc failed on Vega

[Rex Zhu]

Alloc_pte failed when the VA address located in
the higher arrange of 256T.

so reserve the csa buffer under 128T as a work around.

[  122.979425] amdgpu 0000:03:00.0: va above limit (0xFFFFFFFFFFF1F >= 0x1000000000)
[  122.987080] BUG: unable to handle kernel paging request at ffff880e1a79fff8

Signed-off-by: Rex Zhu <Rex.Zhu at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_csa.c | 4 ++--
 drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_csa.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_csa.c
index fea4555..e2f325b 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_csa.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_csa.c
@@ -36,9 +36,9 @@ uint64_t amdgpu_csa_vaddr(struct amdgpu_device *adev, uint32_t id)
 {
 	uint64_t addr = adev->vm_manager.max_pfn << AMDGPU_GPU_PAGE_SHIFT;
 
-	addr -= AMDGPU_VA_RESERVED_SIZE * id;
+	addr = min(addr, AMDGPU_GMC_HOLE_START);
 
-	addr = amdgpu_gmc_sign_extend(addr);
+	addr -= (uint64_t)AMDGPU_VA_RESERVED_SIZE * id;
 
 	return addr;
 }
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
index 338a091..ea6a12a 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
@@ -711,7 +711,7 @@ static int amdgpu_info_ioctl(struct drm_device *dev, void *data, struct drm_file
 
 		dev_info.virtual_address_offset = AMDGPU_VA_RESERVED_SIZE;
 		dev_info.virtual_address_max =
-			min(vm_size, AMDGPU_GMC_HOLE_START);
+			min(vm_size, AMDGPU_GMC_HOLE_START - adev->vm_manager.reserved_vm_size);
 
 		if (vm_size > AMDGPU_GMC_HOLE_START) {
 			dev_info.high_va_offset = AMDGPU_GMC_HOLE_END;
-- 
1.9.1