disk: support MTD partitions

Add new MTD partition driver, which can be useful with
mtdblock driver combination.

Signed-off-by: Alexey Romanov <avromanov@salutedevices.com>
Signed-off-by: Michael Trimarchi <michael@amarulasolutions.com>

disk/part.c

@@ -304,7 +304,8 @@ static void print_part_header(const char *type, struct blk_desc *desc)
 	CONFIG_IS_ENABLED(DOS_PARTITION) || \
 	CONFIG_IS_ENABLED(ISO_PARTITION) || \
 	CONFIG_IS_ENABLED(AMIGA_PARTITION) || \
-	CONFIG_IS_ENABLED(EFI_PARTITION)
+	CONFIG_IS_ENABLED(EFI_PARTITION) || \
+	CONFIG_IS_ENABLED(MTD_PARTITIONS)
 	printf("\nPartition Map for %s device %d  --   Partition Type: %s\n\n",
 	       uclass_get_name(desc->uclass_id), desc->devnum, type);
 #endif /* any CONFIG_..._PARTITION */

drivers/mtd/Kconfig

@@ -2,6 +2,7 @@ menu "MTD Support"
 
 config MTD_PARTITIONS
 	bool
+	select PARTITIONS
 
 config MTD
 	bool "Enable MTD layer"

drivers/mtd/mtdpart.c

@@ -20,6 +20,8 @@
 #endif
 
 #include <malloc.h>
+#include <memalign.h>
+#include <part.h>
 #include <linux/bug.h>
 #include <linux/errno.h>
 #include <linux/compat.h>
@@ -1054,3 +1056,77 @@ uint64_t mtd_get_device_size(const struct mtd_info *mtd)
 	return mtd->size;
 }
 EXPORT_SYMBOL_GPL(mtd_get_device_size);
+
+static struct mtd_info *mtd_get_partition_by_index(struct mtd_info *mtd, int index)
+{
+	struct mtd_info *part;
+	int i = 0;
+
+	list_for_each_entry(part, &mtd->partitions, node)
+		if (i++ == index)
+			return part;
+
+	debug("Partition with idx=%d not found on MTD device %s\n", index, mtd->name);
+	return NULL;
+}
+
+static int __maybe_unused part_get_info_mtd(struct blk_desc *dev_desc, int part_idx,
+					    struct disk_partition *info)
+{
+	struct mtd_info *master = blk_desc_to_mtd(dev_desc);
+	struct mtd_info *part;
+
+	if (!master) {
+		debug("MTD device is NULL\n");
+		return -EINVAL;
+	}
+
+	part = mtd_get_partition_by_index(master, part_idx);
+	if (!part) {
+		debug("Failed to find partition with idx=%d\n", part_idx);
+		return -EINVAL;
+	}
+
+	snprintf(info->name, PART_NAME_LEN, part->name);
+	info->start = part->offset / dev_desc->blksz;
+	info->size = part->size / dev_desc->blksz;
+	info->blksz = dev_desc->blksz;
+
+	return 0;
+}
+
+static void __maybe_unused part_print_mtd(struct blk_desc *dev_desc)
+{
+	struct mtd_info *master = blk_desc_to_mtd(dev_desc);
+	struct mtd_info *part;
+
+	if (!master)
+		return;
+
+	list_for_each_entry(part, &master->partitions, node)
+		printf("- 0x%012llx-0x%012llx : \"%s\"\n",
+		       part->offset, part->offset + part->size, part->name);
+}
+
+static int part_test_mtd(struct blk_desc *dev_desc)
+{
+	struct mtd_info *master = blk_desc_to_mtd(dev_desc);
+	ALLOC_CACHE_ALIGN_BUFFER(unsigned char, buffer, dev_desc->blksz);
+
+	if (!master)
+		return -1;
+
+	if (blk_dread(dev_desc, 0, 1, (ulong *)buffer) != 1)
+		return -1;
+
+	return 0;
+}
+
+U_BOOT_PART_TYPE(mtd) = {
+	.name		= "MTD",
+	.part_type	= PART_TYPE_MTD,
+	.max_entries	= MTD_ENTRY_NUMBERS,
+	.get_info	= part_get_info_ptr(part_get_info_mtd),
+	.print		= part_print_ptr(part_print_mtd),
+	.test		= part_test_mtd,
+};

include/part.h

@@ -30,12 +30,15 @@ struct block_drvr {
 #define PART_TYPE_ISO		0x03
 #define PART_TYPE_AMIGA		0x04
 #define PART_TYPE_EFI		0x05
+#define PART_TYPE_MTD		0x06
 
 /* maximum number of partition entries supported by search */
 #define DOS_ENTRY_NUMBERS	8
 #define ISO_ENTRY_NUMBERS	64
 #define MAC_ENTRY_NUMBERS	64
 #define AMIGA_ENTRY_NUMBERS	8
+#define MTD_ENTRY_NUMBERS	64
+
 /*
  * Type string for U-Boot bootable partitions
  */