Merge tag 'fwu-next-19092024' of https://source.denx.de/u-boot/custodians/u-boot-tpm into next

This PR contains various improvements in the A/B update logic for EFI

- Read both copies of metadata, in case one of the is corrupted
- Check the metadata version against the running firmware to make sure it's
  allowed
- Limit the use of a revert capsule if the board is on a trial state and
  make sure it's not applied if the max counter has expired

include/fwu.h

@@ -417,4 +417,15 @@ int fwu_state_machine_updates(bool trial_state, uint32_t update_index);
  */
 int fwu_init(void);
 
+/**
+ * fwu_bank_accepted() - Has the bank been accepted
+ * @data: Version agnostic FWU metadata information
+ * @bank: Update bank to check
+ *
+ * Check in the given bank if all the images have been accepted.
+ *
+ * Return: true if all images accepted, false otherwise
+ */
+bool fwu_bank_accepted(struct fwu_data *data, uint32_t bank);
+
 #endif /* _FWU_H_ */

lib/efi_loader/efi_capsule.c

@@ -564,9 +564,14 @@ static efi_status_t efi_capsule_update_firmware(
 	bool fw_accept_os;
 
 	if (IS_ENABLED(CONFIG_FWU_MULTI_BANK_UPDATE)) {
-		if (fwu_empty_capsule_checks_pass() &&
-		    fwu_empty_capsule(capsule_data))
-			return fwu_empty_capsule_process(capsule_data);
+		if (fwu_empty_capsule(capsule_data)) {
+			if (fwu_empty_capsule_checks_pass()) {
+				return fwu_empty_capsule_process(capsule_data);
+			} else {
+				log_err("FWU empty capsule checks failed. Cannot start update\n");
+				return EFI_INVALID_PARAMETER;
+			}
+		}
 
 		if (!fwu_update_checks_pass()) {
 			log_err("FWU checks failed. Cannot start update\n");

lib/fwu_updates/Kconfig

@@ -40,6 +40,7 @@ config FWU_MDATA_V1
 
 config FWU_MDATA_V2
 	bool "Enable support FWU Metadata version 2"
+	depends on !FWU_MDATA_V1
 	help
 	  The FWU specification supports two versions of the
 	  metadata structure. This option enables support for FWU

lib/fwu_updates/fwu.c

@@ -28,6 +28,31 @@ enum {
 	IMAGE_ACCEPT_CLEAR,
 };
 
+/**
+ * fwu_bank_accepted() - Has the bank been accepted
+ * @data: Version agnostic FWU metadata information
+ * @bank: Update bank to check
+ *
+ * Check in the given bank if all the images have been accepted.
+ *
+ * Return: true if all images accepted, false otherwise
+ */
+bool fwu_bank_accepted(struct fwu_data *data, uint32_t bank)
+{
+	u32 i;
+	struct fwu_image_entry *img_entry;
+	struct fwu_image_bank_info *img_bank_info;
+
+	img_entry = &data->fwu_images[0];
+	for (i = 0; i < CONFIG_FWU_NUM_IMAGES_PER_BANK; i++) {
+		img_bank_info = &img_entry[i].img_bank_info[bank];
+		if (!img_bank_info->accepted)
+			return false;
+	}
+
+	return true;
+}
+
 static int trial_counter_update(u16 *trial_state_ctr)
 {
 	bool delete;
@@ -88,6 +113,8 @@ static int fwu_trial_count_update(void)
 		ret = fwu_revert_boot_index();
 		if (ret)
 			log_err("Unable to revert active_index\n");
+
+		trial_counter_update(NULL);
 		ret = 1;
 	} else {
 		log_info("Trial State count: attempt %d out of %d\n",
@@ -737,8 +764,8 @@ static int fwu_boottime_checks(void)
 		return 0;
 
 	in_trial = in_trial_state();
-	if (!in_trial || (ret = fwu_trial_count_update()) > 0)
-		ret = trial_counter_update(NULL);
+
+	ret = in_trial ? fwu_trial_count_update() : trial_counter_update(NULL);
 
 	if (!ret)
 		boottime_check = 1;

lib/fwu_updates/fwu_v1.c

@@ -52,11 +52,14 @@ static void fwu_data_init(void)
 	memcpy(dst_img_info, src_img_info, image_info_size);
 }
 
-static int fwu_trial_state_update(bool trial_state)
+static int fwu_trial_state_update(bool trial_state, uint32_t bank)
 {
 	int ret;
 	struct fwu_data *data = fwu_get_data();
 
+	if (!trial_state && !fwu_bank_accepted(data, bank))
+		return 0;
+
 	if (trial_state) {
 		ret = fwu_trial_state_ctr_start();
 		if (ret)
@@ -112,9 +115,9 @@ void fwu_populate_mdata_image_info(struct fwu_data *data)
  * Return: 0 if OK, -ve on error
  */
 int fwu_state_machine_updates(bool trial_state,
-			      __maybe_unused uint32_t update_index)
+			      uint32_t update_index)
 {
-	return fwu_trial_state_update(trial_state);
+	return fwu_trial_state_update(trial_state, update_index);
 }
 
 /**
@@ -146,6 +149,7 @@ int fwu_init(void)
 {
 	int ret;
 	uint32_t mdata_size;
+	struct fwu_mdata mdata = {0};
 
 	fwu_get_mdata_size(&mdata_size);
 
@@ -157,10 +161,16 @@ int fwu_init(void)
 	 * Now read the entire structure, both copies, and
 	 * validate that the copies.
 	 */
-	ret = fwu_get_mdata(NULL);
+	ret = fwu_get_mdata(&mdata);
 	if (ret)
 		return ret;
 
+	if (mdata.version != 0x1) {
+		log_err("FWU metadata version %u. Expected value of %u\n",
+			mdata.version, FWU_MDATA_VERSION);
+		return -EINVAL;
+	}
+
 	fwu_data_init();
 
 	return 0;

lib/fwu_updates/fwu_v2.c

@@ -10,6 +10,9 @@
 #include <linux/types.h>
 
 #define FWU_MDATA_VERSION	0x2U
+#define FWU_IMG_DESC_OFFSET	0x20U
+
+static struct fwu_mdata g_mdata;
 
 static inline struct fwu_fw_store_desc *fwu_get_fw_desc(struct fwu_mdata *mdata)
 {
@@ -58,24 +61,6 @@ static int fwu_mdata_sanity_checks(void)
 	struct fwu_data *data = fwu_get_data();
 	struct fwu_mdata *mdata = data->fwu_mdata;
 
-	if (mdata->version != FWU_MDATA_VERSION) {
-		log_err("FWU metadata version %u. Expected value of %u\n",
-			mdata->version, FWU_MDATA_VERSION);
-		return -EINVAL;
-	}
-
-	if (!mdata->desc_offset) {
-		log_err("No image information provided with the Metadata. ");
-		log_err("Image information expected in the metadata\n");
-		return -EINVAL;
-	}
-
-	if (mdata->desc_offset != 0x20) {
-		log_err("Descriptor Offset(0x%x) in the FWU Metadata not equal to 0x20\n",
-			mdata->desc_offset);
-		return -EINVAL;
-	}
-
 	num_banks = fwu_get_fw_desc(mdata)->num_banks;
 	num_images = fwu_get_fw_desc(mdata)->num_images;
 
@@ -100,6 +85,9 @@ static int fwu_bank_state_update(bool trial_state, uint32_t bank)
 	struct fwu_data *data = fwu_get_data();
 	struct fwu_mdata *mdata = data->fwu_mdata;
 
+	if (!trial_state && !fwu_bank_accepted(data, bank))
+		return 0;
+
 	mdata->bank_state[bank] = data->bank_state[bank] = trial_state ?
 		FWU_BANK_VALID : FWU_BANK_ACCEPTED;
 
@@ -127,6 +115,35 @@ static int fwu_trial_state_start(uint update_index)
 	return 0;
 }
 
+static bool fwu_get_mdata_mandatory(uint part)
+{
+	int ret = 0;
+	struct udevice *fwu_dev = fwu_get_dev();
+
+	memset(&g_mdata, 0, sizeof(struct fwu_mdata));
+
+	ret = fwu_read_mdata(fwu_dev, &g_mdata,
+			     part == PRIMARY_PART ? true : false,
+			     sizeof(struct fwu_mdata));
+	if (ret)
+		return false;
+
+	if (g_mdata.version != FWU_MDATA_VERSION) {
+		log_err("FWU partition %u has metadata version %u. Expected value of %u\n",
+			part, g_mdata.version, FWU_MDATA_VERSION);
+		return false;
+	}
+
+	if (g_mdata.desc_offset != FWU_IMG_DESC_OFFSET) {
+		log_err("Descriptor Offset(0x%x) in the FWU Metadata partition %u not equal to 0x20\n",
+			g_mdata.desc_offset, part);
+		log_err("Image information expected in the metadata\n");
+		return false;
+	}
+
+	return true;
+}
+
 /**
  * fwu_populate_mdata_image_info() - Populate the image information
  * of the metadata
@@ -187,24 +204,14 @@ int fwu_state_machine_updates(bool trial_state, uint32_t update_index)
  */
 int fwu_get_mdata_size(uint32_t *mdata_size)
 {
-	int ret = 0;
-	struct fwu_mdata mdata = { 0 };
 	struct fwu_data *data = fwu_get_data();
-	struct udevice *fwu_dev = fwu_get_dev();
 
 	if (data->metadata_size) {
 		*mdata_size = data->metadata_size;
 		return 0;
 	}
 
-	ret = fwu_read_mdata(fwu_dev, &mdata, 1,
-			     sizeof(struct fwu_mdata));
-	if (ret) {
-		log_err("FWU metadata read failed\n");
-		return ret;
-	}
-
-	*mdata_size = mdata.metadata_size;
+	*mdata_size = g_mdata.metadata_size;
 	if (!*mdata_size)
 		return -EINVAL;
 
@@ -224,21 +231,23 @@ int fwu_get_mdata_size(uint32_t *mdata_size)
 int fwu_init(void)
 {
 	int ret;
-	struct fwu_mdata mdata = { 0 };
-	struct udevice *fwu_dev = fwu_get_dev();
 
 	/*
 	 * First we read only the top level structure
 	 * and get the size of the complete structure.
+	 * Try reading the first partition first, if
+	 * that does not work, try the secondary
+	 * partition. The idea is, if one of the
+	 * partitions is corrupted, it should be restored
+	 * from the intact partition.
 	 */
-	ret = fwu_read_mdata(fwu_dev, &mdata, 1,
-			     sizeof(struct fwu_mdata));
-	if (ret) {
+	if (!fwu_get_mdata_mandatory(PRIMARY_PART) &&
+	    !fwu_get_mdata_mandatory(SECONDARY_PART)) {
 		log_err("FWU metadata read failed\n");
-		return ret;
+		return -1;
 	}
 
-	ret = fwu_mdata_copies_allocate(mdata.metadata_size);
+	ret = fwu_mdata_copies_allocate(g_mdata.metadata_size);
 	if (ret)
 		return ret;