[U-Boot] [PATCH v3 8/8] palmtreo680: add utility that writes u-boot to flash

[Marek Vasut <marex@denx.de>]

Dear Mike Dunn,

> This adds a userspace linux utility that writes the u-boot image to an mtd
> partition on the docg4 nand flash.
> 
> A special utility is required to do this because u-boot is partially loaded
> by an initial program loader (IPL) that is permanently programmed to the
> boot region of the flash.  This IPL expects the image to be written in a
> unique format. The characteristics of this format can be summarized as
> follows: - Flash blocks to be loaded must have a magic number in the oob
> bytes of the first page of the block.
>   - Each page must be written redundantly in the subsequent page.
>   - The integrated flash controller's "reliable mode" is used, requiring
> that alternate 2k regions (4 pages) are skipped when writing.
> For these reasons, a u-boot image can not be written using nandwrite from
> mtd-utils.
> 
> Signed-off-by: Mike Dunn <mikedunn@newsguy.com>
> ---
> Changelog:
>   v3: new patch; split off from patch 7 in v2 of patchset
> 
>  tools/palmtreo680/flash_u-boot.c |  167
> ++++++++++++++++++++++++++++++++++++++ 1 files changed, 167 insertions(+),
> 0 deletions(-)
>  create mode 100644 tools/palmtreo680/flash_u-boot.c
> 
> diff --git a/tools/palmtreo680/flash_u-boot.c
> b/tools/palmtreo680/flash_u-boot.c new file mode 100644
> index 0000000..97b336f
> --- /dev/null
> +++ b/tools/palmtreo680/flash_u-boot.c
> @@ -0,0 +1,167 @@
> +/*
> + * Copyright (C) 2013 Mike Dunn <mikedunn@newsguy.com>
> + *
> + * This file is released under the terms of GPL v2 and any later version.
> + * See the file COPYING in the root directory of the source tree for
> details. + *
> + *
> + * This is a userspace Linux utility that, when run on the Treo 680, will
> + * program u-boot to flash.  The docg4 driver *must* be loaded with the
> + * reliable_mode and ignore_badblocks parameters enabled:
> + *
> + *        modprobe docg4 ignore_badblocks=1 reliable_mode=1
> + *
> + * This utility writes the concatenated spl + u-boot image to the start of
> the + * mtd device in the format expected by the IPL/SPL.  The image file
> and mtd + * device node are passed to the utility as arguments.  The
> blocks must have + * been erased beforehand.
> + *
> + * When you compile this, note that it links to libmtd from mtd-utils, so
> ensure + * that your include and lib paths include this.
> + */
> +
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include <sys/stat.h>
> +#include <fcntl.h>
> +#include <string.h>
> +#include <sys/types.h>
> +#include <unistd.h>
> +#include <errno.h>
> +#include <mtd/mtd-user.h>
> +#include "libmtd.h"
> +
> +#define RELIABLE_BLOCKSIZE  0x10000 /* block capacity in reliable mode */
> +#define STANDARD_BLOCKSIZE  0x40000 /* block capacity in normal mode */
> +#define PAGESIZE 512
> +#define PAGES_PER_BLOCK 512
> +#define OOBSIZE 7		/* available to user (16 total) */
> +
> +uint8_t ff_oob[OOBSIZE] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
> +
> +/* this is the magic number the IPL looks for (ASCII "BIPO") */
> +uint8_t page0_oob[OOBSIZE] = {'B', 'I', 'P', 'O', 0xff, 0xff, 0xff};
> +
> +int main(int argc, char * const argv[])
> +{
> +	int devfd, datafd, num_blocks, block;
> +	off_t file_size;
> +	libmtd_t mtd_desc;
> +	struct mtd_dev_info devinfo;
> +	uint8_t *blockbuf;
> +	char response[8];
> +
> +	if (argc != 3) {
> +		printf("usage: %s <image file> <mtd dev node>\n", argv[0]);
> +		exit(-1);

Use proper errno and "return" as you're returning from main() anyway.

> +	}
> +
> +	mtd_desc = libmtd_open();
> +	if (mtd_desc == NULL) {
> +		fprintf(stderr, "can't initialize libmtd\n");
> +		exit(-1);
> +	}
> +
> +	/* open the spl image file and mtd device */
> +	datafd = open(argv[1], O_RDONLY);
> +	if (datafd == -1) {
> +		perror(argv[1]);
> +		exit(-1);
> +	}
> +	devfd = open(argv[2], O_WRONLY);
> +	if (devfd == -1) {
> +		perror(argv[2]);
> +		exit(-1);
> +	}
> +	if (mtd_get_dev_info(mtd_desc, argv[2], &devinfo) < 0) {
> +		fprintf(stderr, "mtd_get_dev_info failed\n");
> +		exit(-1);
> +	}
> +
> +	/* determine the number of blocks needed by the image */
> +	file_size = lseek(datafd, 0, SEEK_END);
> +	if (file_size == (off_t)-1) {
> +		perror("lseek");
> +		exit(-1);
> +	}
> +	num_blocks = (file_size + RELIABLE_BLOCKSIZE - 1) / RELIABLE_BLOCKSIZE;
> +	file_size = lseek(datafd, 0, SEEK_SET);
> +	if (file_size == (off_t)-1) {
> +		perror("lseek");
> +		exit(-1);
> +	}
> +	printf("The mtd partition contains %d blocks\n", devinfo.eb_cnt);
> +	printf("U-boot will occupy %d blocks\n", num_blocks);
> +	if (num_blocks > devinfo.eb_cnt) {
> +		fprintf(stderr, "Insufficient blocks on partition\n");
> +		exit(-1);
> +	}
> +
> +	printf("IMPORTANT: These blocks must be in an erased state!\n");
> +	printf("Do you want to proceed?\n");
> +	scanf("%s", response);
> +	if ((response[0] != 'y') && (response[0] != 'Y')) {
> +		printf("Exiting\n");
> +		close(devfd);
> +		close(datafd);
> +		exit(-1);
> +	}
> +
> +	blockbuf = malloc(RELIABLE_BLOCKSIZE);

Do you not want to use some calloc() here to make sure the "blockbuf" is zeroed?

> +	if (blockbuf == NULL) {
> +		perror("malloc");
> +		exit(-1);
> +	}
> +
> +	for (block = 0; block < num_blocks; block++) {
> +		int ofs, page;
> +		ssize_t read_ret;
> +		uint8_t *pagebuf = blockbuf, *buf = blockbuf;
> +		uint8_t *oobbuf = page0_oob; /* magic num in oob of 1st page */
> +		size_t len = RELIABLE_BLOCKSIZE;
> +		int ret;
> +
> +		/* read data for one block from file */
> +		while (len != 0 && (read_ret = read(datafd, buf, len)) != 0) {

Uh, this really might be a candidate for IOCCC, split this please ...

> +			if (read_ret == -1) {
> +				if (errno == EINTR)
> +					continue;
> +				perror("read");
> +				exit(-1);
> +			}
> +			len -= read_ret;
> +			buf += read_ret;
> +		}
> +
> +		printf("Block %d: writing\r", block + 1);
> +		fflush(stdout);
> +
> +		for (page = 0, ofs = 0;
> +		     page < PAGES_PER_BLOCK;
> +		     page++, ofs += PAGESIZE) {
> +			if (page & 0x04)  /* Odd-numbered 2k page */
> +				continue; /* skipped in reliable mode */
> +
> +			ret = mtd_write(mtd_desc, &devinfo, devfd, block, ofs,
> +					pagebuf, PAGESIZE, oobbuf, OOBSIZE,
> +					MTD_OPS_PLACE_OOB);
> +			if (ret) {
> +				fprintf(stderr,
> +					"\nmtd_write returned %d on block %d, 
ofs %x\n",
> +					ret, block + 1, ofs);
> +				exit(-1);
> +			}
> +			oobbuf = ff_oob;  /* oob for subsequent pages */
> +
> +			if (page & 0x01)  /* odd-numbered subpage */
> +				pagebuf += PAGESIZE;
> +		}
> +	}
> +
> +	printf("\nDone\n");
> +
> +	close(devfd);
> +	close(datafd);
> +	free(blockbuf);
> +	return 0;
> +}