/* vi: set sw=4 ts=4: */
/* eraseall.c -- erase the whole of a MTD device
 *
 * Ported to busybox from mtd-utils.
 *
 * Copyright (C) 2000 Arcom Control System Ltd
 *
 * Renamed to flash_eraseall.c
 *
 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
 */
//config:config FLASH_ERASEALL
//config:       bool "flash_eraseall"
//config:       default n  # doesn't build on Ubuntu 8.04
//config:       help
//config:         The flash_eraseall binary from mtd-utils as of git head c4c6a59eb.
//config:         This utility is used to erase the whole MTD device.

//applet:IF_FLASH_ERASEALL(APPLET(flash_eraseall, BB_DIR_USR_SBIN, BB_SUID_DROP))

//kbuild:lib-$(CONFIG_FLASH_ERASEALL) += flash_eraseall.o

//usage:#define flash_eraseall_trivial_usage
//usage:       "[-jNq] MTD_DEVICE"
//usage:#define flash_eraseall_full_usage "\n\n"
//usage:       "Erase an MTD device\n"
//usage:     "\n        -j      Format the device for jffs2"
//usage:     "\n        -N      Don't skip bad blocks"
//usage:     "\n        -q      Don't display progress messages"

#include "libbb.h"
#include <mtd/mtd-user.h>
#include <linux/jffs2.h>

#define OPTION_J  (1 << 0)
#define OPTION_N  (1 << 1)
#define OPTION_Q  (1 << 2)
#define IS_NAND   (1 << 3)

/* mtd/jffs2-user.h used to have this atrocity:
extern int target_endian;

#define t16(x) ({ __u16 __b = (x); (target_endian==__BYTE_ORDER)?__b:bswap_16(__b); })
#define t32(x) ({ __u32 __b = (x); (target_endian==__BYTE_ORDER)?__b:bswap_32(__b); })

#define cpu_to_je16(x) ((jint16_t){t16(x)})
#define cpu_to_je32(x) ((jint32_t){t32(x)})
#define cpu_to_jemode(x) ((jmode_t){t32(x)})

#define je16_to_cpu(x) (t16((x).v16))
#define je32_to_cpu(x) (t32((x).v32))
#define jemode_to_cpu(x) (t32((x).m))

but mtd/jffs2-user.h is gone now (at least 2.6.31.6 does not have it anymore)
*/

/* We always use native endianness */
#undef cpu_to_je16
#undef cpu_to_je32
#define cpu_to_je16(v) ((jint16_t){(v)})
#define cpu_to_je32(v) ((jint32_t){(v)})

static void show_progress(mtd_info_t *meminfo, erase_info_t *erase)
{
        printf("\rErasing %u Kibyte @ %x - %2u%% complete.",
                (unsigned)meminfo->erasesize / 1024,
                erase->start,
                (unsigned) ((unsigned long long) erase->start * 100 / meminfo->size)
        );
        fflush_all();
}

int flash_eraseall_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int flash_eraseall_main(int argc UNUSED_PARAM, char **argv)
{
        struct jffs2_unknown_node cleanmarker;
        mtd_info_t meminfo;
        int fd, clmpos, clmlen;
        erase_info_t erase;
        struct stat st;
        unsigned int flags;
        char *mtd_name;

        opt_complementary = "=1";
        flags = getopt32(argv, "jNq");

        mtd_name = argv[optind];
        fd = xopen(mtd_name, O_RDWR);
        fstat(fd, &st);
        if (!S_ISCHR(st.st_mode))
                bb_error_msg_and_die("%s: not a char device", mtd_name);

        xioctl(fd, MEMGETINFO, &meminfo);
        erase.length = meminfo.erasesize;
        if (meminfo.type == MTD_NANDFLASH)
                flags |= IS_NAND;

        clmpos = 0;
        clmlen = 8;
        if (flags & OPTION_J) {
                uint32_t *crc32_table;

                crc32_table = crc32_filltable(NULL, 0);

                cleanmarker.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
                cleanmarker.nodetype = cpu_to_je16(JFFS2_NODETYPE_CLEANMARKER);
                if (!(flags & IS_NAND))
                        cleanmarker.totlen = cpu_to_je32(sizeof(struct jffs2_unknown_node));
                else {
                        struct nand_oobinfo oobinfo;

                        xioctl(fd, MEMGETOOBSEL, &oobinfo);

                        /* Check for autoplacement */
                        if (oobinfo.useecc == MTD_NANDECC_AUTOPLACE) {
                                /* Get the position of the free bytes */
                                clmpos = oobinfo.oobfree[0][0];
                                clmlen = oobinfo.oobfree[0][1];
                                if (clmlen > 8)
                                        clmlen = 8;
                                if (clmlen == 0)
                                        bb_error_msg_and_die("autoplacement selected and no empty space in oob");
                        } else {
                                /* Legacy mode */
                                switch (meminfo.oobsize) {
                                case 8:
                                        clmpos = 6;
                                        clmlen = 2;
                                        break;
                                case 16:
                                        clmpos = 8;
                                        /*clmlen = 8;*/
                                        break;
                                case 64:
                                        clmpos = 16;
                                        /*clmlen = 8;*/
                                        break;
                                }
                        }
                        cleanmarker.totlen = cpu_to_je32(8);
                }

                cleanmarker.hdr_crc = cpu_to_je32(
                        crc32_block_endian0(0, &cleanmarker, sizeof(struct jffs2_unknown_node) - 4, crc32_table)
                );
        }

        /* Don't want to destroy progress indicator by bb_error_msg's */
        applet_name = xasprintf("\n%s: %s", applet_name, mtd_name);

        for (erase.start = 0; erase.start < meminfo.size;
             erase.start += meminfo.erasesize) {
                if (!(flags & OPTION_N)) {
                        int ret;
                        loff_t offset = erase.start;

                        ret = ioctl(fd, MEMGETBADBLOCK, &offset);
                        if (ret > 0) {
                                if (!(flags & OPTION_Q))
                                        printf("\nSkipping bad block at 0x%08x\n", erase.start);
                                continue;
                        }
                        if (ret < 0) {
                                /* Black block table is not available on certain flash
                                 * types e.g. NOR
                                 */
                                if (errno == EOPNOTSUPP) {
                                        flags |= OPTION_N;
                                        if (flags & IS_NAND)
                                                bb_error_msg_and_die("bad block check not available");
                                } else {
                                        bb_perror_msg_and_die("MEMGETBADBLOCK error");
                                }
                        }
                }

                if (!(flags & OPTION_Q))
                        show_progress(&meminfo, &erase);

                xioctl(fd, MEMERASE, &erase);

                /* format for JFFS2 ? */
                if (!(flags & OPTION_J))
                        continue;

                /* write cleanmarker */
                if (flags & IS_NAND) {
                        struct mtd_oob_buf oob;

                        oob.ptr = (unsigned char *) &cleanmarker;
                        oob.start = erase.start + clmpos;
                        oob.length = clmlen;
                        xioctl(fd, MEMWRITEOOB, &oob);
                } else {
                        xlseek(fd, erase.start, SEEK_SET);
                        /* if (lseek(fd, erase.start, SEEK_SET) < 0) {
                                bb_perror_msg("MTD %s failure", "seek");
                                continue;
                        } */
                        xwrite(fd, &cleanmarker, sizeof(cleanmarker));
                        /* if (write(fd, &cleanmarker, sizeof(cleanmarker)) != sizeof(cleanmarker)) {
                                bb_perror_msg("MTD %s failure", "write");
                                continue;
                        } */
                }
                if (!(flags & OPTION_Q))
                        printf(" Cleanmarker written at %x.", erase.start);
        }
        if (!(flags & OPTION_Q)) {
                show_progress(&meminfo, &erase);
                bb_putchar('\n');
        }

        if (ENABLE_FEATURE_CLEAN_UP)
                close(fd);
        return EXIT_SUCCESS;
}