cmd: bcb: introduce 'ab_dump' command to print BCB block content

It's really helpful to have the ability to dump BCB block for debugging
A/B logic on the board supported this partition schema.

Command 'bcb ab_dump' prints all fields of bootloader_control struct
including slot_metadata for all presented slots.

Output example:
=====
> board# bcb ab_dump ubi 0#misc
> Read 512 bytes from volume misc to 000000000bf07580
> Read 512 bytes from volume misc to 000000000bf42f40
> Bootloader Control:       [misc]
> Active Slot:              _a
> Magic Number:             0x42414342
> Version:                  1
> Number of Slots:          2
> Recovery Tries Remaining: 0
> CRC:                      0x2c8b50bc (Valid)
>
> Slot[0] Metadata:
> 	- Priority:         15
> 	- Tries Remaining:  0
> 	- Successful Boot:  1
> 	- Verity Corrupted: 0
>
> Slot[1] Metadata:
> 	- Priority:         14
> 	- Tries Remaining:  7
> 	- Successful Boot:  0
> 	- Verity Corrupted: 0
====

The ab_dump command allows you to display ABC data directly on the
U-Boot console. During an A/B test execution, this test verifies the
accuracy of each field within the ABC data.

Signed-off-by: Dmitry Rokosov <ddrokosov@salutedevices.com>
Reviewed-by: Mattijs Korpershoek <mkorpershoek@baylibre.com>
Tested-by: Mattijs Korpershoek <mkorpershoek@baylibre.com> # vim3_android
Link: https://lore.kernel.org/r/20241017-android_ab_master-v5-5-43bfcc096d95@salutedevices.com
Signed-off-by: Mattijs Korpershoek <mkorpershoek@baylibre.com>

1 files changed, 68 insertions, 0 deletions

diff --git a/boot/android_ab.c b/boot/android_ab.c
index 0045c8133a8..c93e5154101 100644
--- a/boot/android_ab.c
+++ b/boot/android_ab.c
@@ -372,3 +372,71 @@ int ab_select_slot(struct blk_desc *dev_desc, struct disk_partition *part_info,
 
 	return slot;
 }
+
+int ab_dump_abc(struct blk_desc *dev_desc, struct disk_partition *part_info)
+{
+	struct bootloader_control *abc;
+	u32 crc32_le;
+	int i, ret;
+	struct slot_metadata *slot;
+
+	if (!dev_desc || !part_info) {
+		log_err("ANDROID: Empty device descriptor or partition info\n");
+		return -EINVAL;
+	}
+
+	ret = ab_control_create_from_disk(dev_desc, part_info, &abc, 0);
+	if (ret < 0) {
+		log_err("ANDROID: Cannot create bcb from disk %d\n", ret);
+		return ret;
+	}
+
+	if (abc->magic != BOOT_CTRL_MAGIC) {
+		log_err("ANDROID: Unknown A/B metadata: %.8x\n", abc->magic);
+		ret = -ENODATA;
+		goto error;
+	}
+
+	if (abc->version > BOOT_CTRL_VERSION) {
+		log_err("ANDROID: Unsupported A/B metadata version: %.8x\n",
+			abc->version);
+		ret = -ENODATA;
+		goto error;
+	}
+
+	if (abc->nb_slot > ARRAY_SIZE(abc->slot_info)) {
+		log_err("ANDROID: Wrong number of slots %u, expected %zu\n",
+			abc->nb_slot, ARRAY_SIZE(abc->slot_info));
+		ret = -ENODATA;
+		goto error;
+	}
+
+	printf("Bootloader Control:       [%s]\n", part_info->name);
+	printf("Active Slot:              %s\n", abc->slot_suffix);
+	printf("Magic Number:             0x%x\n", abc->magic);
+	printf("Version:                  %u\n", abc->version);
+	printf("Number of Slots:          %u\n", abc->nb_slot);
+	printf("Recovery Tries Remaining: %u\n", abc->recovery_tries_remaining);
+
+	printf("CRC:                      0x%.8x", abc->crc32_le);
+
+	crc32_le = ab_control_compute_crc(abc);
+	if (abc->crc32_le != crc32_le)
+		printf(" (Invalid, Expected: 0x%.8x)\n", crc32_le);
+	else
+		printf(" (Valid)\n");
+
+	for (i = 0; i < abc->nb_slot; ++i) {
+		slot = &abc->slot_info[i];
+		printf("\nSlot[%d] Metadata:\n", i);
+		printf("\t- Priority:         %u\n", slot->priority);
+		printf("\t- Tries Remaining:  %u\n", slot->tries_remaining);
+		printf("\t- Successful Boot:  %u\n", slot->successful_boot);
+		printf("\t- Verity Corrupted: %u\n", slot->verity_corrupted);
+	}
+
+error:
+	free(abc);
+
+	return ret;
+}