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
> ---
> 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 000..97b336f
> --- /dev/null
> +++ b/tools/palmtreo680/flash_u-boot.c
> @@ -0,0 +1,167 @@
> +/*
> + * Copyright (C) 2013 Mike Dunn
> + *
> + * 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
> +#include
> +#include
> +#include
> +#include
> +#include
> +#include
> +#include
> +#include
> +#include "libmtd.h"
> +
> +#define RELIABLE_BLOCKSIZE 0x1 /* block capacity in reliable mode */
> +#define STANDARD_BLOCKSIZE 0x4 /* 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 \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')) {
> + pri