feat(fwu): modify the check for getting the FWU bank's state

The version 2 of the FWU metadata structure has a field bank_state in
the top level of the structure which can be used to check if a given
bank is in the either of Trial State, Accepted State, or in an Invalid
State. This is different from the binary states of Valid/Accepted
States that the bank could be in, as defined in the earlier version of
the specification.

Replace the fwu_is_trial_run_state() API with
fwu_get_active_bank_state() to get the state the current active bank
is in. The value returned by this API is then used by the caller to
take appropriate action.

Change-Id: I764f486840a3713bfe5f8e03d0634bfe09b23590
Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org>

drivers/auth/auth_mod.c

@@ -328,7 +328,6 @@ static int auth_nvctr(const auth_method_param_nv_ctr_t *param,
 	unsigned int data_len, len, i;
 	unsigned int plat_nv_ctr;
 	int rc;
-	bool is_trial_run = false;
 
 	/* Get the counter value from current image. The AM expects the IPM
 	 * to return the counter value as a DER encoded integer */
@@ -388,9 +387,14 @@ static int auth_nvctr(const auth_method_param_nv_ctr_t *param,
 		return 1;
 	} else if (*cert_nv_ctr > plat_nv_ctr) {
 #if PSA_FWU_SUPPORT && IMAGE_BL2
-		is_trial_run = fwu_is_trial_run_state();
+		if (fwu_get_active_bank_state() == FWU_BANK_STATE_ACCEPTED) {
+			*need_nv_ctr_upgrade = true;
+		} else {
+			*need_nv_ctr_upgrade = false;
+		}
+#else
+		*need_nv_ctr_upgrade = true;
 #endif /* PSA_FWU_SUPPORT && IMAGE_BL2 */
-		*need_nv_ctr_upgrade = !is_trial_run;
 	}
 
 	return 0;

drivers/fwu/fwu.c

@@ -133,28 +133,23 @@ exit:
 }
 
 /*******************************************************************************
- * The system runs in the trial run state if any of the images in the active
+ * The platform can be in one of Valid, Invalid or Accepted states.
- * firmware bank has not been accepted yet.
  *
- * Returns true if the system is running in the trial state.
+ * Invalid - One or more images in the bank are corrupted, or partially
+ *           overwritten. The bank is not to be used for booting.
+ *
+ * Valid - All images of the bank are valid but at least one image has not
+ *         been accepted. This implies that the platform is in Trial State.
+ *
+ * Accepted - All images of the bank are valid and accepted.
+ *
+ * Returns the state of the current active bank
  ******************************************************************************/
-bool fwu_is_trial_run_state(void)
+uint32_t fwu_get_active_bank_state(void)
 {
-	bool trial_run = false;
-
 	assert(is_metadata_initialized);
 
-	for (unsigned int i = 0U; i < NR_OF_IMAGES_IN_FW_BANK; i++) {
+	return metadata.bank_state[metadata.active_index];
-		struct fwu_image_entry *entry = &metadata.img_entry[i];
-		struct fwu_image_properties *img_props =
-			&entry->img_props[metadata.active_index];
-		if (img_props->accepted == 0) {
-			trial_run = true;
-			break;
-		}
-	}
-
-	return trial_run;
 }
 
 const struct fwu_metadata *fwu_get_metadata(void)

include/drivers/fwu/fwu.h

@@ -14,7 +14,7 @@
 #define FWU_BANK_STATE_INVALID		0xFFU
 
 void fwu_init(void);
-bool fwu_is_trial_run_state(void);
+uint32_t fwu_get_active_bank_state(void);
 const struct fwu_metadata *fwu_get_metadata(void);
 
 #endif /* FWU_H */