drm/amdgpu: add atomfirmware helper function to query fw cap

Fimware capability was changed from 16 bits to 32 bits
for atomfirmware. add helper funciton to query firmware
capability and cache the value at early stage.

Signed-off-by: Hawking Zhang <[e-mail]>
Reviewed-by: Alex Deucher <[e-mail]>
Reviewed-by: John Clements <[e-mail]>
Signed-off-by: Alex Deucher <[e-mail]>

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

···
 	if (adev->is_atom_fw) {
 		amdgpu_atomfirmware_scratch_regs_init(adev);
 		amdgpu_atomfirmware_allocate_fb_scratch(adev);
+		/* cached firmware_flags for further usage */
+		adev->mode_info.firmware_flags =
+			amdgpu_atomfirmware_query_firmware_capability(adev);
 	} else {
 		amdgpu_atombios_scratch_regs_init(adev);
 		amdgpu_atombios_allocate_fb_scratch(adev);

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

···
 #include "atombios.h"
 #include "soc15_hw_ip.h"
 
+union firmware_info {
+	struct atom_firmware_info_v3_1 v31;
+	struct atom_firmware_info_v3_2 v32;
+	struct atom_firmware_info_v3_3 v33;
+	struct atom_firmware_info_v3_4 v34;
+};
+
+/*
+ * Helper function to query firmware capability
+ *
+ * @adev: amdgpu_device pointer
+ *
+ * Return firmware_capability in firmwareinfo table on success or 0 if not
+ */
+uint32_t amdgpu_atomfirmware_query_firmware_capability(struct amdgpu_device *adev)
+{
+	struct amdgpu_mode_info *mode_info = &adev->mode_info;
+	int index;
+	u16 data_offset, size;
+	union firmware_info *firmware_info;
+	u8 frev, crev;
+	u32 fw_cap = 0;
+
+	index = get_index_into_master_table(atom_master_list_of_data_tables_v2_1,
+			firmwareinfo);
+
+	if (amdgpu_atom_parse_data_header(adev->mode_info.atom_context,
+				index, &size, &frev, &crev, &data_offset)) {
+		/* support firmware_info 3.1 + */
+		if ((frev == 3 && crev >=1) || (frev > 3)) {
+			firmware_info = (union firmware_info *)
+				(mode_info->atom_context->bios + data_offset);
+			fw_cap = le32_to_cpu(firmware_info->v31.firmware_capability);
+		}
+	}
+
+	return fw_cap;
+}
+
 bool amdgpu_atomfirmware_gpu_supports_virtualization(struct amdgpu_device *adev)
 {
 	int index = get_index_into_master_table(atom_master_list_of_data_tables_v2_1,
···
 	return ecc_default_enabled;
 }
 
-union firmware_info {
-	struct atom_firmware_info_v3_1 v31;
-	struct atom_firmware_info_v3_2 v32;
-	struct atom_firmware_info_v3_3 v33;
-	struct atom_firmware_info_v3_4 v34;
-};
-
 /*
  * Return true if vbios supports sram ecc or false if not
  */
···
 
 		adev->pm.current_sclk = adev->clock.default_sclk;
 		adev->pm.current_mclk = adev->clock.default_mclk;
-
-		/* not technically a clock, but... */
-		adev->mode_info.firmware_flags =
-			le32_to_cpu(firmware_info->v31.firmware_capability);
 
 		ret = 0;
 	}

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

···
 
 #define get_index_into_master_table(master_table, table_name) (offsetof(struct master_table, table_name) / sizeof(uint16_t))
 
+uint32_t amdgpu_atomfirmware_query_firmware_capability(struct amdgpu_device *adev);
 bool amdgpu_atomfirmware_gpu_supports_virtualization(struct amdgpu_device *adev);
 void amdgpu_atomfirmware_scratch_regs_init(struct amdgpu_device *adev);
 int amdgpu_atomfirmware_allocate_fb_scratch(struct amdgpu_device *adev);

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

···
 	/* pointer to fbdev info structure */
 	struct amdgpu_fbdev *rfbdev;
 	/* firmware flags */
-	u16 firmware_flags;
+	u32 firmware_flags;
 	/* pointer to backlight encoder */
 	struct amdgpu_encoder *bl_encoder;
 	u8 bl_level; /* saved backlight level */