drm/amdgpu: add asic callback for BACO support

BACO - Bus Active, Chip Off

Used to check whether the device supports BACO.  This will
be used to enable runtime pm on devices which support BACO.
Reviewed-by: NEvan Quan <evan.quan@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu.h

@@ -589,6 +589,8 @@ struct amdgpu_asic_funcs {
 	bool (*need_reset_on_init)(struct amdgpu_device *adev);
 	/* PCIe replay counter */
 	uint64_t (*get_pcie_replay_count)(struct amdgpu_device *adev);
+	/* device supports BACO */
+	bool (*supports_baco)(struct amdgpu_device *adev);
 };
 
 /*
@@ -1120,6 +1122,8 @@ int emu_soc_asic_init(struct amdgpu_device *adev);
 #define amdgpu_asic_get_pcie_usage(adev, cnt0, cnt1) ((adev)->asic_funcs->get_pcie_usage((adev), (cnt0), (cnt1)))
 #define amdgpu_asic_need_reset_on_init(adev) (adev)->asic_funcs->need_reset_on_init((adev))
 #define amdgpu_asic_get_pcie_replay_count(adev) ((adev)->asic_funcs->get_pcie_replay_count((adev)))
+#define amdgpu_asic_supports_baco(adev) (adev)->asic_funcs->supports_baco((adev))
+
 #define amdgpu_inc_vram_lost(adev) atomic_inc(&((adev)->vram_lost_counter));
 
 /* Common functions */