drm/i915/huc: Add more errors for I915_PARAM_HUC_STATUS

There might be many reasons why we failed to successfully
load and authenticate HuC firmware, but today we only use
single error in case of no HuC hardware. Add some more
error codes for most common cases (disabled, not installed,
corrupted or mismatched firmware).
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Tony Ye <tony.ye@intel.com>
Cc: Robert M. Fosha <robert.m.fosha@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200330113302.1670-1-michal.wajdeczko@intel.com

drivers/gpu/drm/i915/gt/uc/intel_huc.c

@@ -200,9 +200,13 @@ int intel_huc_auth(struct intel_huc *huc)
  * This function reads status register to verify if HuC
  * firmware was successfully loaded.
  *
- * Returns: 1 if HuC firmware is loaded and verified,
- * 0 if HuC firmware is not loaded and -ENODEV if HuC
- * is not present on this platform.
+ * Returns:
+ *  * -ENODEV if HuC is not present on this platform,
+ *  * -EOPNOTSUPP if HuC firmware is disabled,
+ *  * -ENOPKG if HuC firmware was not installed,
+ *  * -ENOEXEC if HuC firmware is invalid or mismatched,
+ *  * 0 if HuC firmware is not running,
+ *  * 1 if HuC firmware is authenticated and running.
  */
 int intel_huc_check_status(struct intel_huc *huc)
 {
@@ -210,8 +214,18 @@ int intel_huc_check_status(struct intel_huc *huc)
 	intel_wakeref_t wakeref;
 	u32 status = 0;
 
-	if (!intel_huc_is_supported(huc))
+	switch (__intel_uc_fw_status(&huc->fw)) {
+	case INTEL_UC_FIRMWARE_NOT_SUPPORTED:
 		return -ENODEV;
+	case INTEL_UC_FIRMWARE_DISABLED:
+		return -EOPNOTSUPP;
+	case INTEL_UC_FIRMWARE_MISSING:
+		return -ENOPKG;
+	case INTEL_UC_FIRMWARE_ERROR:
+		return -ENOEXEC;
+	default:
+		break;
+	}
 
 	with_intel_runtime_pm(gt->uncore->rpm, wakeref)
 		status = intel_uncore_read(gt->uncore, huc->status.reg);