fastboot: Allow u-boot-style partitions

This adds support for partitions of the form "dev.hwpart:part" and
"dev#partname". This allows one to flash to eMMC boot partitions without
having to use CONFIG_FASTBOOT_MMC_BOOT1_SUPPORT. It also allows one to
flash to an entire device without needing CONFIG_FASTBOOT_MMC_USER_NAME.
Lastly, one can also flash MMC devices other than
CONFIG_FASTBOOT_FLASH_MMC_DEV.

Because devices can be specified explicitly, CONFIG_FASTBOOT_FLASH_MMC_DEV
is used only when necessary for existing functionality. For those cases,
fastboot_mmc_get_dev has been added as a helper function. This allows

There should be no conflicts with the existing system, but just in case, I
have ordered detection of these names after all existing names.

The fastboot_mmc_part test has been updated for these new names.

Signed-off-by: Sean Anderson <sean.anderson@seco.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

1 files changed, 98 insertions, 59 deletions

diff --git a/drivers/fastboot/fb_mmc.c b/drivers/fastboot/fb_mmc.c
index 71eeb02c8f..8e74e50e91 100644
--- a/drivers/fastboot/fb_mmc.c
+++ b/drivers/fastboot/fb_mmc.c
@@ -76,12 +76,37 @@ static int raw_part_get_info_by_name(struct blk_desc *dev_desc,
 	return 0;
 }
 
-static int part_get_info_by_name_or_alias(struct blk_desc *dev_desc,
-		const char *name, struct disk_partition *info)
+static int do_get_part_info(struct blk_desc **dev_desc, const char *name,
+			    struct disk_partition *info)
 {
 	int ret;
 
-	ret = part_get_info_by_name(dev_desc, name, info);
+	/* First try partition names on the default device */
+	*dev_desc = blk_get_dev("mmc", CONFIG_FASTBOOT_FLASH_MMC_DEV);
+	if (*dev_desc) {
+		ret = part_get_info_by_name(*dev_desc, name, info);
+		if (ret >= 0)
+			return ret;
+
+		/* Then try raw partitions */
+		ret = raw_part_get_info_by_name(*dev_desc, name, info);
+		if (ret >= 0)
+			return ret;
+	}
+
+	/* Then try dev.hwpart:part */
+	ret = part_get_info_by_dev_and_name_or_num("mmc", name, dev_desc,
+						   info, true);
+	return ret;
+}
+
+static int part_get_info_by_name_or_alias(struct blk_desc **dev_desc,
+					  const char *name,
+					  struct disk_partition *info)
+{
+	int ret;
+
+	ret = do_get_part_info(dev_desc, name, info);
 	if (ret < 0) {
 		/* strlen("fastboot_partition_alias_") + PART_NAME_LEN + 1 */
 		char env_alias_name[25 + PART_NAME_LEN + 1];
@@ -92,8 +117,8 @@ static int part_get_info_by_name_or_alias(struct blk_desc *dev_desc,
 		strncat(env_alias_name, name, PART_NAME_LEN);
 		aliased_part_name = env_get(env_alias_name);
 		if (aliased_part_name != NULL)
-			ret = part_get_info_by_name(dev_desc,
-					aliased_part_name, info);
+			ret = do_get_part_info(dev_desc, aliased_part_name,
+					       info);
 	}
 	return ret;
 }
@@ -430,27 +455,49 @@ int fastboot_mmc_get_part_info(const char *part_name,
 			       struct blk_desc **dev_desc,
 			       struct disk_partition *part_info, char *response)
 {
-	int r = 0;
+	int ret;
 
-	*dev_desc = blk_get_dev("mmc", CONFIG_FASTBOOT_FLASH_MMC_DEV);
-	if (!*dev_desc) {
-		fastboot_fail("block device not found", response);
-		return -ENOENT;
-	}
 	if (!part_name || !strcmp(part_name, "")) {
 		fastboot_fail("partition not given", response);
 		return -ENOENT;
 	}
 
-	if (raw_part_get_info_by_name(*dev_desc, part_name, part_info) < 0) {
-		r = part_get_info_by_name_or_alias(*dev_desc, part_name, part_info);
-		if (r < 0) {
-			fastboot_fail("partition not found", response);
-			return r;
+	ret = part_get_info_by_name_or_alias(dev_desc, part_name, part_info);
+	if (ret < 0) {
+		switch (ret) {
+		case -ENOSYS:
+		case -EINVAL:
+			fastboot_fail("invalid partition or device", response);
+			break;
+		case -ENODEV:
+			fastboot_fail("no such device", response);
+			break;
+		case -ENOENT:
+			fastboot_fail("no such partition", response);
+			break;
+		case -EPROTONOSUPPORT:
+			fastboot_fail("unknown partition table type", response);
+			break;
+		default:
+			fastboot_fail("unanticipated error", response);
+			break;
 		}
 	}
 
-	return r;
+	return ret;
+}
+
+static struct blk_desc *fastboot_mmc_get_dev(char *response)
+{
+	struct blk_desc *ret = blk_get_dev("mmc",
+					   CONFIG_FASTBOOT_FLASH_MMC_DEV);
+
+	if (!ret || ret->type == DEV_TYPE_UNKNOWN) {
+		pr_err("invalid mmc device\n");
+		fastboot_fail("invalid mmc device", response);
+		return NULL;
+	}
+	return ret;
 }
 
 /**
@@ -467,22 +514,19 @@ void fastboot_mmc_flash_write(const char *cmd, void *download_buffer,
 	struct blk_desc *dev_desc;
 	struct disk_partition info;
 
-	dev_desc = blk_get_dev("mmc", CONFIG_FASTBOOT_FLASH_MMC_DEV);
-	if (!dev_desc || dev_desc->type == DEV_TYPE_UNKNOWN) {
-		pr_err("invalid mmc device\n");
-		fastboot_fail("invalid mmc device", response);
-		return;
-	}
-
 #ifdef CONFIG_FASTBOOT_MMC_BOOT_SUPPORT
 	if (strcmp(cmd, CONFIG_FASTBOOT_MMC_BOOT1_NAME) == 0) {
-		fb_mmc_boot_ops(dev_desc, download_buffer, 1,
-				download_bytes, response);
+		dev_desc = fastboot_mmc_get_dev(response);
+		if (dev_desc)
+			fb_mmc_boot_ops(dev_desc, download_buffer, 1,
+					download_bytes, response);
 		return;
 	}
 	if (strcmp(cmd, CONFIG_FASTBOOT_MMC_BOOT2_NAME) == 0) {
-		fb_mmc_boot_ops(dev_desc, download_buffer, 2,
-				download_bytes, response);
+		dev_desc = fastboot_mmc_get_dev(response);
+		if (dev_desc)
+			fb_mmc_boot_ops(dev_desc, download_buffer, 1,
+					download_bytes, response);
 		return;
 	}
 #endif
@@ -494,6 +538,10 @@ void fastboot_mmc_flash_write(const char *cmd, void *download_buffer,
 	if (strcmp(cmd, CONFIG_FASTBOOT_GPT_NAME) == 0 ||
 	    strcmp(cmd, CONFIG_FASTBOOT_MMC_USER_NAME) == 0) {
 #endif
+		dev_desc = fastboot_mmc_get_dev(response);
+		if (!dev_desc)
+			return;
+
 		printf("%s: updating MBR, Primary and Backup GPT(s)\n",
 		       __func__);
 		if (is_valid_gpt_buf(dev_desc, download_buffer)) {
@@ -517,6 +565,10 @@ void fastboot_mmc_flash_write(const char *cmd, void *download_buffer,
 
 #if CONFIG_IS_ENABLED(DOS_PARTITION)
 	if (strcmp(cmd, CONFIG_FASTBOOT_MBR_NAME) == 0) {
+		dev_desc = fastboot_mmc_get_dev(response);
+		if (!dev_desc)
+			return;
+
 		printf("%s: updating MBR\n", __func__);
 		if (is_valid_dos_buf(download_buffer)) {
 			printf("%s: invalid MBR - refusing to write to flash\n",
@@ -539,19 +591,16 @@ void fastboot_mmc_flash_write(const char *cmd, void *download_buffer,
 
 #ifdef CONFIG_ANDROID_BOOT_IMAGE
 	if (strncasecmp(cmd, "zimage", 6) == 0) {
-		fb_mmc_update_zimage(dev_desc, download_buffer,
-				     download_bytes, response);
+		dev_desc = fastboot_mmc_get_dev(response);
+		if (dev_desc)
+			fb_mmc_update_zimage(dev_desc, download_buffer,
+					     download_bytes, response);
 		return;
 	}
 #endif
 
-	if (raw_part_get_info_by_name(dev_desc, cmd, &info) != 0) {
-		if (part_get_info_by_name_or_alias(dev_desc, cmd, &info) < 0) {
-			pr_err("cannot find partition: '%s'\n", cmd);
-			fastboot_fail("cannot find partition", response);
-			return;
-		}
-	}
+	if (fastboot_mmc_get_part_info(cmd, &dev_desc, &info, response) < 0)
+		return;
 
 	if (is_sparse_image(download_buffer)) {
 		struct fb_mmc_sparse sparse_priv;
@@ -594,28 +643,19 @@ void fastboot_mmc_erase(const char *cmd, char *response)
 	lbaint_t blks, blks_start, blks_size, grp_size;
 	struct mmc *mmc = find_mmc_device(CONFIG_FASTBOOT_FLASH_MMC_DEV);
 
-	if (mmc == NULL) {
-		pr_err("invalid mmc device\n");
-		fastboot_fail("invalid mmc device", response);
-		return;
-	}
-
-	dev_desc = blk_get_dev("mmc", CONFIG_FASTBOOT_FLASH_MMC_DEV);
-	if (!dev_desc || dev_desc->type == DEV_TYPE_UNKNOWN) {
-		pr_err("invalid mmc device\n");
-		fastboot_fail("invalid mmc device", response);
-		return;
-	}
-
 #ifdef CONFIG_FASTBOOT_MMC_BOOT_SUPPORT
 	if (strcmp(cmd, CONFIG_FASTBOOT_MMC_BOOT1_NAME) == 0) {
 		/* erase EMMC boot1 */
-		fb_mmc_boot_ops(dev_desc, NULL, 1, 0, response);
+		dev_desc = fastboot_mmc_get_dev(response);
+		if (dev_desc)
+			fb_mmc_boot_ops(dev_desc, NULL, 1, 0, response);
 		return;
 	}
 	if (strcmp(cmd, CONFIG_FASTBOOT_MMC_BOOT2_NAME) == 0) {
 		/* erase EMMC boot2 */
-		fb_mmc_boot_ops(dev_desc, NULL, 2, 0, response);
+		dev_desc = fastboot_mmc_get_dev(response);
+		if (dev_desc)
+			fb_mmc_boot_ops(dev_desc, NULL, 1, 0, response);
 		return;
 	}
 #endif
@@ -623,6 +663,10 @@ void fastboot_mmc_erase(const char *cmd, char *response)
 #ifdef CONFIG_FASTBOOT_MMC_USER_SUPPORT
 	if (strcmp(cmd, CONFIG_FASTBOOT_MMC_USER_NAME) == 0) {
 		/* erase EMMC userdata */
+		dev_desc = fastboot_mmc_get_dev(response);
+		if (!dev_desc)
+			return;
+
 		if (fb_mmc_erase_mmc_hwpart(dev_desc))
 			fastboot_fail("Failed to erase EMMC_USER", response);
 		else
@@ -631,13 +675,8 @@ void fastboot_mmc_erase(const char *cmd, char *response)
 	}
 #endif
 
-	if (raw_part_get_info_by_name(dev_desc, cmd, &info) != 0) {
-		if (part_get_info_by_name_or_alias(dev_desc, cmd, &info) < 0) {
-			pr_err("cannot find partition: '%s'\n", cmd);
-			fastboot_fail("cannot find partition", response);
-			return;
-		}
-	}
+	if (fastboot_mmc_get_part_info(cmd, &dev_desc, &info, response) < 0)
+		return;
 
 	/* Align blocks to erase group size to avoid erasing other partitions */
 	grp_size = mmc->erase_grp_size;