part: Allow setting the partition-table type

Some devices have multiple partition types available on the same media.
It is sometimes useful to see these to check that everything is working
correctly.

Provide a way to manually set the partition-table type, avoiding the
auto-detection process.

Signed-off-by: Simon Glass <[email protected]>
Reviewed-by: Bin Meng <[email protected]>

Author: sjg20

cmd/part.c

@@ -182,6 +182,36 @@ static int do_part_number(int argc, char *const argv[])
 	return do_part_info(argc, argv, CMD_PART_INFO_NUMBER);
 }
 
+static int do_part_set(int argc, char *const argv[])
+{
+	const char *devname, *partstr, *typestr;
+	struct blk_desc *desc;
+	int dev;
+
+	if (argc < 3)
+		return CMD_RET_USAGE;
+
+	/* Look up the device */
+	devname = argv[0];
+	partstr = argv[1];
+	typestr = argv[2];
+	dev = blk_get_device_by_str(devname, partstr, &desc);
+	if (dev < 0) {
+		printf("** Bad device specification %s %s **\n", devname,
+		       partstr);
+		return CMD_RET_FAILURE;
+	}
+
+	desc->part_type = part_get_type_by_name(typestr);
+	if (!desc->part_type) {
+		printf("Unknown partition type '%s'\n", typestr);
+		return CMD_RET_FAILURE;
+	}
+	part_print(desc);
+
+	return 0;
+}
+
 #ifdef CONFIG_PARTITION_TYPE_GUID
 static int do_part_type(int argc, char *const argv[])
 {
@@ -245,6 +275,8 @@ static int do_part(struct cmd_tbl *cmdtp, int flag, int argc,
 		return do_part_number(argc - 2, argv + 2);
 	else if (!strcmp(argv[1], "types"))
 		return do_part_types(argc - 2, argv + 2);
+	else if (!strcmp(argv[1], "set"))
+		return do_part_set(argc - 2, argv + 2);
 #ifdef CONFIG_PARTITION_TYPE_GUID
 	else if (!strcmp(argv[1], "type"))
 		return do_part_type(argc - 2, argv + 2);
@@ -279,6 +311,8 @@ U_BOOT_CMD(
 #endif
 	"part type <interface> <dev>:<part> <varname>\n"
 	"    - set environment variable to partition type\n"
+	"part set <interface> <dev> type\n"
+	"    - set partition type for a device\n"
 	"part types\n"
 	"    - list supported partition table types"
 );

disk/part.c

@@ -54,6 +54,22 @@ static struct part_driver *part_driver_lookup_type(struct blk_desc *dev_desc)
 	return NULL;
 }
 
+int part_get_type_by_name(const char *name)
+{
+	struct part_driver *drv =
+		ll_entry_start(struct part_driver, part_driver);
+	const int n_ents = ll_entry_count(struct part_driver, part_driver);
+	struct part_driver *entry;
+
+	for (entry = drv; entry != drv + n_ents; entry++) {
+		if (!strcasecmp(name, entry->name))
+			return entry->part_type;
+	}
+
+	/* Not found */
+	return PART_TYPE_UNKNOWN;
+}
+
 static struct blk_desc *get_dev_hwpart(const char *ifname, int dev, int hwpart)
 {
 	struct blk_desc *dev_desc;

doc/usage/cmd/part.rst

@@ -13,6 +13,7 @@ Synopis
     part start <interface> <dev> <part> <varname>
     part size <interface> <dev> <part> <varname>
     part number <interface> <dev> <part> <varname>
+    part set <interface> <dev> <part> <type>
     part type <interface> <dev>:<part> [varname]
     part types
 
@@ -82,6 +83,18 @@ part must be specified as partition name.
     varname
         a variable to store the current partition number value into
 
+The 'part set' command sets the type of a partition. This is useful when
+autodetection fails or does not do the correct thing:
+
+    interface
+        interface for accessing the block device (mmc, sata, scsi, usb, ....)
+    dev
+        device number
+    part
+        partition number
+    type
+        partition type to use (see 'part types') to check available types
+
 The 'part type' command prints or sets an environment variable to the partition type UUID.
 
     interface
@@ -147,6 +160,67 @@ Examples
     => part types
     Supported partition tables: EFI, AMIGA, DOS, ISO, MAC
 
+This shows looking at a device with multiple partition tables::
+
+    => virtio scan
+    => part list virtio 0
+
+    Partition Map for VirtIO device 0  --   Partition Type: EFI
+
+    Part	Start LBA	End LBA		Name
+            Attributes
+            Type GUID
+            Partition GUID
+    1	0x00000040	0x0092b093	"ISO9660"
+            attrs:	0x1000000000000001
+            type:	ebd0a0a2-b9e5-4433-87c0-68b6b72699c7
+            guid:	a0891d7e-b930-4513-94d8-f629dbd637b2
+    2	0x0092b094	0x0092d7e7	"Appended2"
+            attrs:	0x0000000000000000
+            type:	c12a7328-f81f-11d2-ba4b-00a0c93ec93b
+            guid:	a0891d7e-b930-4513-94db-f629dbd637b2
+    3	0x0092d7e8	0x0092da3f	"Gap1"
+            attrs:	0x1000000000000001
+            type:	ebd0a0a2-b9e5-4433-87c0-68b6b72699c7
+            guid:	a0891d7e-b930-4513-94da-f629dbd637b2
+    => ls virtio 0:3
+    => part types
+    Supported partition tables: EFI, DOS, ISO
+    => part set virtio 0 dos
+
+    Partition Map for VirtIO device 0  --   Partition Type: DOS
+
+    Part	Start Sector	Num Sectors	UUID		Type
+    1	1         	9624191   	00000000-01	ee
+    => part set virtio 0 iso
+
+    Partition Map for VirtIO device 0  --   Partition Type: ISO
+
+    Part   Start     Sect x Size Type
+    1     3020        4    512 U-Boot
+    2  9613460    10068    512 U-Boot
+    => part set virtio 0 efi
+
+    Partition Map for VirtIO device 0  --   Partition Type: EFI
+
+    Part	Start LBA	End LBA		Name
+            Attributes
+            Type GUID
+            Partition GUID
+    1	0x00000040	0x0092b093	"ISO9660"
+            attrs:	0x1000000000000001
+            type:	ebd0a0a2-b9e5-4433-87c0-68b6b72699c7
+            guid:	a0891d7e-b930-4513-94d8-f629dbd637b2
+    2	0x0092b094	0x0092d7e7	"Appended2"
+            attrs:	0x0000000000000000
+            type:	c12a7328-f81f-11d2-ba4b-00a0c93ec93b
+            guid:	a0891d7e-b930-4513-94db-f629dbd637b2
+    3	0x0092d7e8	0x0092da3f	"Gap1"
+            attrs:	0x1000000000000001
+            type:	ebd0a0a2-b9e5-4433-87c0-68b6b72699c7
+            guid:	a0891d7e-b930-4513-94da-f629dbd637b2
+    =>
+
 Return value
 ------------
 

include/part.h

@@ -598,6 +598,15 @@ static inline struct part_driver *part_driver_get_first(void)
 	return ll_entry_start(struct part_driver, part_driver);
 }
 
+/**
+ * part_get_type_by_name() - Get partition type by name
+ *
+ * @name: Name of partition type to look up (not case-sensitive)
+ * Returns: Corresponding partition type (PART_TYPE_...) or PART_TYPE_UNKNOWN if
+ * not known
+ */
+int part_get_type_by_name(const char *name);
+
 #else
 static inline int part_driver_get_count(void)
 { return 0; }