u-boot/cmd/bcb.c
Eugeniu Rosca 37f1811a0b cmd: bcb: Apply non-functional refinements
These have been reported by Simon in [1] and fixed in [2].
However, since [1] has already been pushed to u-boot/master, the
improvements incorporated in [2] are now extracted and resubmitted.

The changes are in the area of coding style and best practices:
* s/field/fieldp/, s/size/sizep/, to convey that the variables return
  an output to the caller
* s/err_1/err_read_fail/, s/err_2/err_too_small/, to be more descriptive
* Made sure 'static int do_bcb_load' appears on the same line
* Placed a `/*` on top of multi-line comment

[1] https://patchwork.ozlabs.org/patch/1104244/#2200259
[2] https://patchwork.ozlabs.org/cover/1128661/
   ("[v4,0/4] Add 'bcb' command to read/modify/write Android BCB")

Fixes: db7b7a05b2 ("cmd: Add 'bcb' command to read/modify/write BCB fields")
Reported-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Eugeniu Rosca <erosca@de.adit-jv.com>
Reviewed-by: Sam Protsenko <semen.protsenko@linaro.org>
2019-07-24 13:16:29 -04:00

338 lines
7.7 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2019 Eugeniu Rosca <rosca.eugeniu@gmail.com>
*
* Command to read/modify/write Android BCB fields
*/
#include <android_bootloader_message.h>
#include <command.h>
#include <common.h>
enum bcb_cmd {
BCB_CMD_LOAD,
BCB_CMD_FIELD_SET,
BCB_CMD_FIELD_CLEAR,
BCB_CMD_FIELD_TEST,
BCB_CMD_FIELD_DUMP,
BCB_CMD_STORE,
};
static int bcb_dev = -1;
static int bcb_part = -1;
static struct bootloader_message bcb = { { 0 } };
static int bcb_cmd_get(char *cmd)
{
if (!strcmp(cmd, "load"))
return BCB_CMD_LOAD;
if (!strcmp(cmd, "set"))
return BCB_CMD_FIELD_SET;
if (!strcmp(cmd, "clear"))
return BCB_CMD_FIELD_CLEAR;
if (!strcmp(cmd, "test"))
return BCB_CMD_FIELD_TEST;
if (!strcmp(cmd, "store"))
return BCB_CMD_STORE;
if (!strcmp(cmd, "dump"))
return BCB_CMD_FIELD_DUMP;
else
return -1;
}
static int bcb_is_misused(int argc, char *const argv[])
{
int cmd = bcb_cmd_get(argv[0]);
switch (cmd) {
case BCB_CMD_LOAD:
case BCB_CMD_FIELD_SET:
if (argc != 3)
goto err;
break;
case BCB_CMD_FIELD_TEST:
if (argc != 4)
goto err;
break;
case BCB_CMD_FIELD_CLEAR:
if (argc != 1 && argc != 2)
goto err;
break;
case BCB_CMD_STORE:
if (argc != 1)
goto err;
break;
case BCB_CMD_FIELD_DUMP:
if (argc != 2)
goto err;
break;
default:
printf("Error: 'bcb %s' not supported\n", argv[0]);
return -1;
}
if (cmd != BCB_CMD_LOAD && (bcb_dev < 0 || bcb_part < 0)) {
printf("Error: Please, load BCB first!\n");
return -1;
}
return 0;
err:
printf("Error: Bad usage of 'bcb %s'\n", argv[0]);
return -1;
}
static int bcb_field_get(char *name, char **fieldp, int *sizep)
{
if (!strcmp(name, "command")) {
*fieldp = bcb.command;
*sizep = sizeof(bcb.command);
} else if (!strcmp(name, "status")) {
*fieldp = bcb.status;
*sizep = sizeof(bcb.status);
} else if (!strcmp(name, "recovery")) {
*fieldp = bcb.recovery;
*sizep = sizeof(bcb.recovery);
} else if (!strcmp(name, "stage")) {
*fieldp = bcb.stage;
*sizep = sizeof(bcb.stage);
} else if (!strcmp(name, "reserved")) {
*fieldp = bcb.reserved;
*sizep = sizeof(bcb.reserved);
} else {
printf("Error: Unknown bcb field '%s'\n", name);
return -1;
}
return 0;
}
static int do_bcb_load(cmd_tbl_t *cmdtp, int flag, int argc,
char * const argv[])
{
struct blk_desc *desc;
disk_partition_t info;
u64 cnt;
char *endp;
int part, ret;
ret = blk_get_device_by_str("mmc", argv[1], &desc);
if (ret < 0)
goto err_read_fail;
part = simple_strtoul(argv[2], &endp, 0);
if (*endp == '\0') {
ret = part_get_info(desc, part, &info);
if (ret)
goto err_read_fail;
} else {
part = part_get_info_by_name(desc, argv[2], &info);
if (part < 0) {
ret = part;
goto err_read_fail;
}
}
cnt = DIV_ROUND_UP(sizeof(struct bootloader_message), info.blksz);
if (cnt > info.size)
goto err_too_small;
if (blk_dread(desc, info.start, cnt, &bcb) != cnt) {
ret = -EIO;
goto err_read_fail;
}
bcb_dev = desc->devnum;
bcb_part = part;
debug("%s: Loaded from mmc %d:%d\n", __func__, bcb_dev, bcb_part);
return CMD_RET_SUCCESS;
err_read_fail:
printf("Error: mmc %s:%s read failed (%d)\n", argv[1], argv[2], ret);
goto err;
err_too_small:
printf("Error: mmc %s:%s too small!", argv[1], argv[2]);
goto err;
err:
bcb_dev = -1;
bcb_part = -1;
return CMD_RET_FAILURE;
}
static int do_bcb_set(cmd_tbl_t *cmdtp, int flag, int argc,
char * const argv[])
{
int size, len;
char *field, *str, *found;
if (bcb_field_get(argv[1], &field, &size))
return CMD_RET_FAILURE;
len = strlen(argv[2]);
if (len >= size) {
printf("Error: sizeof('%s') = %d >= %d = sizeof(bcb.%s)\n",
argv[2], len, size, argv[1]);
return CMD_RET_FAILURE;
}
str = argv[2];
field[0] = '\0';
while ((found = strsep(&str, ":"))) {
if (field[0] != '\0')
strcat(field, "\n");
strcat(field, found);
}
return CMD_RET_SUCCESS;
}
static int do_bcb_clear(cmd_tbl_t *cmdtp, int flag, int argc,
char * const argv[])
{
int size;
char *field;
if (argc == 1) {
memset(&bcb, 0, sizeof(bcb));
return CMD_RET_SUCCESS;
}
if (bcb_field_get(argv[1], &field, &size))
return CMD_RET_FAILURE;
memset(field, 0, size);
return CMD_RET_SUCCESS;
}
static int do_bcb_test(cmd_tbl_t *cmdtp, int flag, int argc,
char * const argv[])
{
int size;
char *field;
char *op = argv[2];
if (bcb_field_get(argv[1], &field, &size))
return CMD_RET_FAILURE;
if (*op == '=' && *(op + 1) == '\0') {
if (!strncmp(argv[3], field, size))
return CMD_RET_SUCCESS;
else
return CMD_RET_FAILURE;
} else if (*op == '~' && *(op + 1) == '\0') {
if (!strstr(field, argv[3]))
return CMD_RET_FAILURE;
else
return CMD_RET_SUCCESS;
} else {
printf("Error: Unknown operator '%s'\n", op);
}
return CMD_RET_FAILURE;
}
static int do_bcb_dump(cmd_tbl_t *cmdtp, int flag, int argc,
char * const argv[])
{
int size;
char *field;
if (bcb_field_get(argv[1], &field, &size))
return CMD_RET_FAILURE;
print_buffer((ulong)field - (ulong)&bcb, (void *)field, 1, size, 16);
return CMD_RET_SUCCESS;
}
static int do_bcb_store(cmd_tbl_t *cmdtp, int flag, int argc,
char * const argv[])
{
struct blk_desc *desc;
disk_partition_t info;
u64 cnt;
int ret;
desc = blk_get_devnum_by_type(IF_TYPE_MMC, bcb_dev);
if (!desc) {
ret = -ENODEV;
goto err;
}
ret = part_get_info(desc, bcb_part, &info);
if (ret)
goto err;
cnt = DIV_ROUND_UP(sizeof(struct bootloader_message), info.blksz);
if (blk_dwrite(desc, info.start, cnt, &bcb) != cnt) {
ret = -EIO;
goto err;
}
return CMD_RET_SUCCESS;
err:
printf("Error: mmc %d:%d write failed (%d)\n", bcb_dev, bcb_part, ret);
return CMD_RET_FAILURE;
}
static cmd_tbl_t cmd_bcb_sub[] = {
U_BOOT_CMD_MKENT(load, CONFIG_SYS_MAXARGS, 1, do_bcb_load, "", ""),
U_BOOT_CMD_MKENT(set, CONFIG_SYS_MAXARGS, 1, do_bcb_set, "", ""),
U_BOOT_CMD_MKENT(clear, CONFIG_SYS_MAXARGS, 1, do_bcb_clear, "", ""),
U_BOOT_CMD_MKENT(test, CONFIG_SYS_MAXARGS, 1, do_bcb_test, "", ""),
U_BOOT_CMD_MKENT(dump, CONFIG_SYS_MAXARGS, 1, do_bcb_dump, "", ""),
U_BOOT_CMD_MKENT(store, CONFIG_SYS_MAXARGS, 1, do_bcb_store, "", ""),
};
static int do_bcb(cmd_tbl_t *cmdtp, int flag, int argc, char *const argv[])
{
cmd_tbl_t *c;
if (argc < 2)
return CMD_RET_USAGE;
argc--;
argv++;
c = find_cmd_tbl(argv[0], cmd_bcb_sub, ARRAY_SIZE(cmd_bcb_sub));
if (!c)
return CMD_RET_USAGE;
if (bcb_is_misused(argc, argv)) {
/*
* We try to improve the user experience by reporting the
* root-cause of misusage, so don't return CMD_RET_USAGE,
* since the latter prints out the full-blown help text
*/
return CMD_RET_FAILURE;
}
return c->cmd(cmdtp, flag, argc, argv);
}
U_BOOT_CMD(
bcb, CONFIG_SYS_MAXARGS, 1, do_bcb,
"Load/set/clear/test/dump/store Android BCB fields",
"load <dev> <part> - load BCB from mmc <dev>:<part>\n"
"bcb set <field> <val> - set BCB <field> to <val>\n"
"bcb clear [<field>] - clear BCB <field> or all fields\n"
"bcb test <field> <op> <val> - test BCB <field> against <val>\n"
"bcb dump <field> - dump BCB <field>\n"
"bcb store - store BCB back to mmc\n"
"\n"
"Legend:\n"
"<dev> - MMC device index containing the BCB partition\n"
"<part> - MMC partition index or name containing the BCB\n"
"<field> - one of {command,status,recovery,stage,reserved}\n"
"<op> - the binary operator used in 'bcb test':\n"
" '=' returns true if <val> matches the string stored in <field>\n"
" '~' returns true if <val> matches a subset of <field>'s string\n"
"<val> - string/text provided as input to bcb {set,test}\n"
" NOTE: any ':' character in <val> will be replaced by line feed\n"
" during 'bcb set' and used as separator by upper layers\n"
);