diff options
author | Chris Ball <cjb@laptop.org> | 2012-10-19 16:49:55 -0400 |
---|---|---|
committer | Chris Ball <cjb@laptop.org> | 2012-10-19 17:28:08 -0400 |
commit | f74dfe23cd00894aa9f235374468e05acb793e17 (patch) | |
tree | b949ad457fb17ee67650da0364a32a24997bb9eb | |
parent | bf4ae7d4e936ac70eab71ee7fc85b01b4ecf8786 (diff) | |
download | mmc-utils-f74dfe23cd00894aa9f235374468e05acb793e17.tar.gz |
Support enable/disable of eMMC H/W Reset function
(Note: one-time programmable fuse.)
$ mmc hwreset enable /dev/mmcblk0
$ mmc hwreset disable /dev/mmcblk0
-rw-r--r-- | mmc.c | 10 | ||||
-rw-r--r-- | mmc.h | 4 | ||||
-rw-r--r-- | mmc_cmds.c | 59 | ||||
-rw-r--r-- | mmc_cmds.h | 2 |
4 files changed, 75 insertions, 0 deletions
@@ -80,6 +80,16 @@ static struct Command commands[] = { "Enable the eMMC BKOPS feature on <device>.\nNOTE! This is a one-time programmable (unreversible) change.", NULL }, + { do_hwreset_en, -1, + "hwreset enable", "<device>\n" + "Permanently enable the eMMC H/W Reset feature on <device>.\nNOTE! This is a one-time programmable (unreversible) change.", + NULL + }, + { do_hwreset_dis, -1, + "hwreset disable", "<device>\n" + "Permanently disable the eMMC H/W Reset feature on <device>.\nNOTE! This is a one-time programmable (unreversible) change.", + NULL + }, { 0, 0, 0, 0 } }; @@ -39,6 +39,7 @@ #define EXT_CSD_BOOT_WP 173 #define EXT_CSD_WR_REL_PARAM 166 #define EXT_CSD_BKOPS_EN 163 /* R/W */ +#define EXT_CSD_RST_N_FUNCTION 162 /* R/W */ #define EXT_CSD_NATIVE_SECTOR_SIZE 63 /* R */ #define EXT_CSD_USE_NATIVE_SECTOR 62 /* R/W */ #define EXT_CSD_DATA_SECTOR_SIZE 61 /* R */ @@ -70,6 +71,9 @@ #define EXT_CSD_BOOT_CFG_ACK (1<<6) #define EXT_CSD_BOOT_CFG_EN (0x38) #define EXT_CSD_BOOT_CFG_ACC (0x03) +#define EXT_CSD_RST_N_EN_MASK (0x03) +#define EXT_CSD_HW_RESET_EN (0x01) +#define EXT_CSD_HW_RESET_DIS (0x02) #define EXT_CSD_PART_CONFIG_ACC_MASK (0x7) #define EXT_CSD_PART_CONFIG_ACC_BOOT0 (0x1) #define EXT_CSD_PART_CONFIG_ACC_BOOT1 (0x2) @@ -280,6 +280,65 @@ int do_write_boot_en(int nargs, char **argv) return ret; } +int do_hwreset(int value, int nargs, char **argv) +{ + __u8 ext_csd[512]; + int fd, ret; + char *device; + + CHECK(nargs != 2, "Usage: mmc hwreset enable </path/to/mmcblkX>\n", + exit(1)); + + device = argv[1]; + + fd = open(device, O_RDWR); + if (fd < 0) { + perror("open"); + exit(1); + } + + ret = read_extcsd(fd, ext_csd); + if (ret) { + fprintf(stderr, "Could not read EXT_CSD from %s\n", device); + exit(1); + } + + if ((ext_csd[EXT_CSD_RST_N_FUNCTION] & EXT_CSD_RST_N_EN_MASK) == + EXT_CSD_HW_RESET_EN) { + fprintf(stderr, + "H/W Reset is already permanently enabled on %s\n", + device); + exit(1); + } + if ((ext_csd[EXT_CSD_RST_N_FUNCTION] & EXT_CSD_RST_N_EN_MASK) == + EXT_CSD_HW_RESET_DIS) { + fprintf(stderr, + "H/W Reset is already permanently disabled on %s\n", + device); + exit(1); + } + + ret = write_extcsd_value(fd, EXT_CSD_RST_N_FUNCTION, value); + if (ret) { + fprintf(stderr, + "Could not write 0x%02x to EXT_CSD[%d] in %s\n", + value, EXT_CSD_RST_N_FUNCTION, device); + exit(1); + } + + return ret; +} + +int do_hwreset_en(int nargs, char **argv) +{ + return do_hwreset(EXT_CSD_HW_RESET_EN, nargs, argv); +} + +int do_hwreset_dis(int nargs, char **argv) +{ + return do_hwreset(EXT_CSD_HW_RESET_DIS, nargs, argv); +} + int do_write_bkops_en(int nargs, char **argv) { __u8 ext_csd[512], value = 0; @@ -22,3 +22,5 @@ int do_writeprotect_set(int nargs, char **argv); int do_disable_512B_emulation(int nargs, char **argv); int do_write_boot_en(int nargs, char **argv); int do_write_bkops_en(int nargs, char **argv); +int do_hwreset_en(int nargs, char **argv); +int do_hwreset_dis(int nargs, char **argv); |