[U-Boot] [PATCH v6 29/31] cmd: mtd: add 'mtd' command

Boris Brezillon boris.brezillon at bootlin.com
Thu Aug 16 19:50:58 UTC 2018


On Thu, 16 Aug 2018 17:30:27 +0200
Miquel Raynal <miquel.raynal at bootlin.com> wrote:

> There should not be a 'nand' command, a 'sf' command and certainly not
> a new 'spi-nand' command. Write a 'mtd' command instead to manage all
> MTD devices/partitions at once. This should be the preferred way to
> access any MTD device.
> 
> Signed-off-by: Miquel Raynal <miquel.raynal at bootlin.com>
> Acked-by: Jagan Teki <jagan at openedev.com>
> ---
>  cmd/Kconfig             |   7 +
>  cmd/Makefile            |   1 +
>  cmd/mtd.c               | 513 ++++++++++++++++++++++++++++++++++++++++
>  drivers/mtd/Makefile    |   2 +-
>  include/linux/mtd/mtd.h |   1 +
>  5 files changed, 523 insertions(+), 1 deletion(-)
>  create mode 100644 cmd/mtd.c
> 
> diff --git a/cmd/Kconfig b/cmd/Kconfig
> index ef43ed8dda..81351920ab 100644
> --- a/cmd/Kconfig
> +++ b/cmd/Kconfig
> @@ -847,6 +847,13 @@ config CMD_MMC_SWRITE
>  	  Enable support for the "mmc swrite" command to write Android sparse
>  	  images to eMMC.
>  
> +config CMD_MTD
> +	bool "mtd"
> +	depends on CMD_MTDPARTS
> +	select MTD_PARTITIONS
> +	help
> +	  MTD commands support.
> +
>  config CMD_NAND
>  	bool "nand"
>  	default y if NAND_SUNXI
> diff --git a/cmd/Makefile b/cmd/Makefile
> index 323f1fd2c7..32fd102189 100644
> --- a/cmd/Makefile
> +++ b/cmd/Makefile
> @@ -90,6 +90,7 @@ obj-$(CONFIG_CMD_MISC) += misc.o
>  obj-$(CONFIG_CMD_MMC) += mmc.o
>  obj-$(CONFIG_CMD_MMC_SPI) += mmc_spi.o
>  obj-$(CONFIG_MP) += mp.o
> +obj-$(CONFIG_CMD_MTD) += mtd.o
>  obj-$(CONFIG_CMD_MTDPARTS) += mtdparts.o
>  obj-$(CONFIG_CMD_NAND) += nand.o
>  obj-$(CONFIG_CMD_NET) += net.o
> diff --git a/cmd/mtd.c b/cmd/mtd.c
> new file mode 100644
> index 0000000000..b9d58725f0
> --- /dev/null
> +++ b/cmd/mtd.c
> @@ -0,0 +1,513 @@
> +// SPDX-License-Identifier:  GPL-2.0+
> +/*
> + * mtd.c
> + *
> + * Generic command to handle basic operations on any memory device.
> + *
> + * Copyright: Bootlin, 2018
> + * Author: Miquèl Raynal <miquel.raynal at bootlin.com>
> + */
> +
> +#include <command.h>
> +#include <common.h>
> +#include <console.h>
> +#include <linux/mtd/mtd.h>
> +#include <linux/mtd/partitions.h>
> +#include <malloc.h>
> +#include <mapmem.h>
> +#include <dm/device.h>
> +#include <dm/uclass-internal.h>
> +
> +#define MTD_NAME_MAX_LEN 20
> +
> +static void mtd_dump_buf(u8 *buf, uint len, uint offset)
> +{
> +	int i, j;
> +
> +	for (i = 0; i < len; ) {
> +		printf("0x%08x:\t", offset + i);
> +		for (j = 0; j < 8; j++)
> +			printf("%02x ", buf[i + j]);
> +		printf(" ");
> +		i += 8;
> +		for (j = 0; j < 8; j++)
> +			printf("%02x ", buf[i + j]);
> +		printf("\n");
> +		i += 8;
> +	}
> +}
> +
> +static void mtd_show_parts(struct mtd_info *mtd, int level)
> +{
> +	struct mtd_info *part;
> +	int i;
> +
> +	if (list_empty(&mtd->partitions))
> +		return;
> +
> +	list_for_each_entry(part, &mtd->partitions, node) {
> +		for (i = 0; i < level; i++)
> +			printf("\t");
> +		printf("* %s\n", part->name);
> +		for (i = 0; i < level; i++)
> +			printf("\t");
> +		printf("  > Offset: 0x%llx bytes\n", part->offset);
> +		for (i = 0; i < level; i++)
> +			printf("\t");
> +		printf("  > Size: 0x%llx bytes\n", part->size);
> +
> +		mtd_show_parts(part, level + 1);
> +	}
> +}
> +
> +static void mtd_show_device(struct mtd_info *mtd)
> +{
> +	/* Device */
> +	printf("* %s", mtd->name);
> +	if (mtd->dev)
> +		printf(" [device: %s] [parent: %s] [driver: %s]",
> +		       mtd->dev->name, mtd->dev->parent->name,
> +		       mtd->dev->driver->name);
> +	printf("\n");
> +
> +	/* MTD device information */
> +	printf("  > type: ");
> +	switch (mtd->type) {
> +	case MTD_RAM:
> +		printf("RAM\n");
> +		break;
> +	case MTD_ROM:
> +		printf("ROM\n");
> +		break;
> +	case MTD_NORFLASH:
> +		printf("NOR flash\n");
> +		break;
> +	case MTD_NANDFLASH:
> +		printf("NAND flash\n");
> +		break;
> +	case MTD_DATAFLASH:
> +		printf("Data flash\n");
> +		break;
> +	case MTD_UBIVOLUME:
> +		printf("UBI volume\n");
> +		break;
> +	case MTD_MLCNANDFLASH:
> +		printf("MLC NAND flash\n");
> +		break;
> +	case MTD_ABSENT:
> +	default:
> +		printf("Unknown\n");
> +		break;
> +	}
> +
> +	printf("  > Size: 0x%llx bytes\n", mtd->size);
> +	printf("  > Block: 0x%x bytes\n", mtd->erasesize);
> +	printf("  > Min I/O: 0x%x bytes\n", mtd->writesize);
> +
> +	if (mtd->oobsize) {
> +		printf("  > OOB size: %u bytes\n", mtd->oobsize);
> +		printf("  > OOB available: %u bytes\n", mtd->oobavail);
> +	}
> +
> +	if (mtd->ecc_strength) {
> +		printf("  > ECC strength: %u bits\n", mtd->ecc_strength);
> +		printf("  > ECC step size: %u bytes\n", mtd->ecc_step_size);
> +		printf("  > Bitflip threshold: %u bits\n",
> +		       mtd->bitflip_threshold);
> +	}
> +
> +	/* MTD partitions, if any */
> +	mtd_show_parts(mtd, 1);
> +}
> +
> +/*
> + * Ensure the MTD device partition list has been initialized already (needed for
> + * non DM-compliant devices).
> + */
> +static void mtd_quirk_init_non_dm_device_lists(void)
> +{
> +	struct mtd_info *mtd;
> +
> +	mtd_for_each_device(mtd) {
> +		if (!mtd_is_partition(mtd) && !mtd->partitions.next) {
> +			INIT_LIST_HEAD(&mtd->partitions);
> +			INIT_LIST_HEAD(&mtd->node);
> +		}
> +	}
> +}
> +
> +#if IS_ENABLED(CONFIG_DM)
> +static void mtd_probe_uclass_mtd_devs(void)
> +{
> +	struct udevice *dev;
> +	int idx = 0;
> +
> +	/* Probe devices with DM compliant drivers */
> +	while (!uclass_find_device(UCLASS_MTD, idx, &dev) && dev) {
> +		mtd_probe(dev);
> +		idx++;
> +	}
> +}
> +#else
> +static void mtd_probe_uclass_mtd_devs(void) { }
> +#endif
> +
> +int mtd_probe_devices(void)
> +{
> +	const char *mtdparts = env_get("mtdparts");
> +
> +	mtd_quirk_init_non_dm_device_lists();
> +
> +	mtd_probe_uclass_mtd_devs();
> +
> +	/* Create the partitions defined in mtdparts, here the fun begins */
> +
> +	/* Ignore the extra 'mtdparts=' prefix if any */
> +	if (strstr(mtdparts, "mtdparts="))
> +		mtdparts += 9;
> +
> +	/* For each MTD device in mtdparts */
> +	while (mtdparts[0] != '\0') {

Hm, so you're unconditionally re-parsing mtdparts, even if nothing
changed since the last time you parsed it? Might be expensing if mtd
read/write is called iteratively on small MTD portions.

> +		struct mtd_partition *parts;
> +		struct list_head *iterator;
> +		bool part_in_use = false;
> +		struct mtd_info *parent;
> +		char mtdname[MTD_NAME_MAX_LEN];
> +		int mtdname_len, len, ret;
> +
> +		mtdname_len = strchr(mtdparts, ':') - mtdparts;

What if mtdparts is malformed? strchr() might return NULL if it didn't
find ':', and you probably want to stop parsing mtdparts in that case.

> +		strncpy(mtdname, mtdparts, mtdname_len);
> +		mtdname[mtdname_len] = '\0';
> +		/* Move the pointer forward (including the ':') */
> +		mtdparts += mtdname_len + 1;
> +		parent = get_mtd_device_nm(mtdname);
> +		if (IS_ERR_OR_NULL(parent)) {
> +			char altname[MTD_NAME_MAX_LEN];
> +
> +			/*
> +			 * The MTD device named "mtdname" does not exist. Try to
> +			 * find a correspondance with an MTD device having the
> +			 * same type and number as defined in the mtdids.
> +			 */
> +			printf("No device named %s\n", mtdname);
> +
> +			ret = mtdparts_init();
> +			if (ret) {
> +				printf("Could not initialize mtdparts\n");
> +				return ret;
> +			}
> +
> +			ret = mtdids_search_alternate_name(mtdname, altname,
> +							   MTD_NAME_MAX_LEN);
> +			if (ret)  {
> +				printf("Did not found an equivalent in mtdids\n");
> +				return ret;
> +			}
> +
> +			parent = get_mtd_device_nm(altname);
> +			if (IS_ERR_OR_NULL(parent)) {
> +				printf("No device named %s\n", altname);
> +				return -EINVAL;
> +			}
> +		}
> +		put_mtd_device(parent);
> +
> +		/*
> +		 * Parse the MTD device partitions. It will update the mtdparts
> +		 * pointer, create an array of parts (that must be freed), and
> +		 * return the number of partition structures in the array.
> +		 */
> +		ret = mtdparts_parse_part(parent, &mtdparts, &parts, &len);
> +		if (ret) {
> +			printf("Could not parse device %s\n", parent->name);
> +			return -EINVAL;
> +		}
> +
> +		if (!len)
> +			continue;
> +
> +		/* Check that no partition is actually in use */
> +		list_for_each(iterator, &parent->partitions) {
> +			struct mtd_info *p = mtd_part_node_to_info(iterator);
> +
> +			if (p->usecount) {
> +				printf("MTD partition \"%s\" already in use.\n",
> +				       p->name);
> +				part_in_use = true;
> +			}
> +		}
> +
> +		if (part_in_use) {
> +			printf("Not reconstructing partition list for MTD device %s\n",
> +			       parent->name);
> +			continue;
> +		}
> +
> +		/* Free the existing partitions */
> +		del_mtd_partitions(parent);
> +
> +		/* Create the new MTD partitions */
> +		add_mtd_partitions(parent, parts, len);
> +		free(parts);
> +	}
> +
> +	return 0;
> +}
> +
> +static uint mtd_len_to_pages(struct mtd_info *mtd, u64 len)
> +{
> +	do_div(len, mtd->writesize);
> +
> +	return len;
> +}
> +
> +static bool mtd_is_aligned_with_min_io_size(struct mtd_info *mtd, u64 size)
> +{
> +	return do_div(size, mtd->writesize);
> +}
> +
> +static bool mtd_is_aligned_with_block_size(struct mtd_info *mtd, u64 size)
> +{
> +	return do_div(size, mtd->erasesize);
> +}
> +
> +static int do_mtd_list(void)
> +{
> +	struct mtd_info *mtd;
> +	int dev_nb = 0;
> +
> +	/* Ensure all devices (and their partitions) are probed */
> +	mtd_probe_devices();
> +
> +	printf("List of MTD devices:\n");
> +	mtd_for_each_device(mtd) {
> +		if (!mtd_is_partition(mtd))
> +			mtd_show_device(mtd);

I would print partitions too, and if possible, put them under the
master device with an extra level of indentation.

> +
> +		dev_nb++;
> +	}
> +
> +	if (!dev_nb) {
> +		printf("No MTD device found\n");
> +		return CMD_RET_FAILURE;
> +	}
> +
> +	return 0;
> +}
> +
> +static int do_mtd(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
> +{
> +	struct mtd_info *mtd;
> +	const char *cmd;
> +	char *mtdname;
> +	int ret;
> +
> +	/* All MTD commands need at least two arguments */
> +	if (argc < 2)
> +		return CMD_RET_USAGE;
> +
> +	/* Parse the command name and its optional suffixes */
> +	cmd = argv[1];
> +
> +	/* List the MTD devices if that is what the user wants */
> +	if (strcmp(cmd, "list") == 0)
> +		return do_mtd_list();
> +
> +	/*
> +	 * The remaining commands require also at least a device ID.
> +	 * Check the selected device is valid. Ensure it is probed.
> +	 */
> +	if (argc < 3)
> +		return CMD_RET_USAGE;
> +
> +	mtdname = argv[2];
> +	mtd = get_mtd_device_nm(mtdname);
> +	if (IS_ERR_OR_NULL(mtd)) {
> +		mtd_probe_devices();

Actually this should be done unconditionally, just in case the object
returned by get_mtd_device_nm() is a partition. mtdparts env var might
have changed between the 2 mtd xxx calls, and the partition we've been
given might no longer be valid. The solution would be to avoid
re-parsing things when mtdparts didn't change (you can check that
in mtd_probe_devices()).

> +		mtd = get_mtd_device_nm(mtdname);
> +		if (IS_ERR_OR_NULL(mtd)) {
> +			printf("MTD device %s not found, ret %ld\n",
> +			       mtdname, PTR_ERR(mtd));
> +			return 1;

			return CMD_RET_FAILURE;

> +		}
> +	}
> +	put_mtd_device(mtd);
> +

Why do you call put_mtd_device() here? You should retain the reference
until you're done interacting with the device.


More information about the U-Boot mailing list