Allow passing the partition name to "part start" and "part size" commands, so we can avoid magic numbers in the environment.
Consider one real use-case: in include/environment/ti/boot.h we have commands like these:
setenv boot_part 9 part start mmc ${mmcdev} ${boot_part} boot_start part size mmc ${mmcdev} ${boot_part} boot_size mmc read ${loadaddr} ${boot_start} ${boot_size}
Now suppose that we have changed the partition table and boot_part now is 10. We will need to fix commands above. And anyone who relies on these boot commands, will need to change them accordingly, too (this was an actual case in our lab while testing Linux boot on Android environment).
By providing the option to pass partition name instead, we fix mentioned issue, by eliminating the necessity to use magic numbers.
Signed-off-by: Sam Protsenko semen.protsenko@linaro.org --- cmd/part.c | 36 +++++++++++++++++++++++++----------- 1 file changed, 25 insertions(+), 11 deletions(-)
diff --git a/cmd/part.c b/cmd/part.c index 746bf40b2d..fd8825a7ec 100644 --- a/cmd/part.c +++ b/cmd/part.c @@ -113,6 +113,7 @@ static int do_part_start(int argc, char * const argv[]) struct blk_desc *desc; disk_partition_t info; char buf[512] = { 0 }; + char *endp; int part; int err; int ret; @@ -122,15 +123,20 @@ static int do_part_start(int argc, char * const argv[]) if (argc > 4) return CMD_RET_USAGE;
- part = simple_strtoul(argv[2], NULL, 0); - ret = blk_get_device_by_str(argv[0], argv[1], &desc); if (ret < 0) return 1;
- err = part_get_info(desc, part, &info); - if (err) - return 1; + part = simple_strtoul(argv[2], &endp, 0); + if (*endp == '\0') { + err = part_get_info(desc, part, &info); + if (err) + return 1; + } else { + part = part_get_info_by_name(desc, argv[2], &info); + if (part == -1) + return 1; + }
snprintf(buf, sizeof(buf), LBAF, info.start);
@@ -147,6 +153,7 @@ static int do_part_size(int argc, char * const argv[]) struct blk_desc *desc; disk_partition_t info; char buf[512] = { 0 }; + char *endp; int part; int err; int ret; @@ -156,15 +163,20 @@ static int do_part_size(int argc, char * const argv[]) if (argc > 4) return CMD_RET_USAGE;
- part = simple_strtoul(argv[2], NULL, 0); - ret = blk_get_device_by_str(argv[0], argv[1], &desc); if (ret < 0) return 1;
- err = part_get_info(desc, part, &info); - if (err) - return 1; + part = simple_strtoul(argv[2], &endp, 0); + if (*endp == '\0') { + err = part_get_info(desc, part, &info); + if (err) + return 1; + } else { + part = part_get_info_by_name(desc, argv[2], &info); + if (part == -1) + return 1; + }
snprintf(buf, sizeof(buf), LBAF, info.size);
@@ -207,6 +219,8 @@ U_BOOT_CMD( " flags can be -bootable (list only bootable partitions)\n" "part start <interface> <dev> <part> <varname>\n" " - set environment variable to the start of the partition (in blocks)\n" + " part can be either partition number or partition name\n" "part size <interface> <dev> <part> <varname>\n" - " - set environment variable to the size of the partition (in blocks)" + " - set environment variable to the size of the partition (in blocks)\n" + " part can be either partition number or partition name" );