5.4-stable review patch. If anyone has any objections, please let me know.
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From: Arnd Bergmann arnd@arndb.de
[ Upstream commit 822130b5e8834ab30ad410cf19a582e5014b9a85 ]
On 32-bit architectures comparing a resource against a value larger than U32_MAX can cause a warning:
drivers/gpu/drm/amd/amdgpu/amdgpu_device.c:1344:18: error: result of comparison of constant 4294967296 with expression of type 'resource_size_t' (aka 'unsigned int') is always false [-Werror,-Wtautological-constant-out-of-range-compare] res->start > 0x100000000ull) ~~~~~~~~~~ ^ ~~~~~~~~~~~~~~
As gcc does not warn about this in dead code, add an IS_ENABLED() check at the start of the function. This will always return success but not actually resize the BAR on 32-bit architectures without high memory, which is exactly what we want here, as the driver can fall back to bank switching the VRAM access.
Fixes: 31b8adab3247 ("drm/amdgpu: require a root bus window above 4GB for BAR resize") Reviewed-by: Christian König christian.koenig@amd.com Signed-off-by: Arnd Bergmann arnd@arndb.de Signed-off-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c index d0e1fd011de54..e5032eb9ae291 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c @@ -759,6 +759,9 @@ int amdgpu_device_resize_fb_bar(struct amdgpu_device *adev) u16 cmd; int r;
+ if (!IS_ENABLED(CONFIG_PHYS_ADDR_T_64BIT)) + return 0; + /* Bypass for VF */ if (amdgpu_sriov_vf(adev)) return 0;