--- /dev/null
+// 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 (!strncmp(cmd, "load", sizeof("load")))
+ return BCB_CMD_LOAD;
+ if (!strncmp(cmd, "set", sizeof("set")))
+ return BCB_CMD_FIELD_SET;
+ if (!strncmp(cmd, "clear", sizeof("clear")))
+ return BCB_CMD_FIELD_CLEAR;
+ if (!strncmp(cmd, "test", sizeof("test")))
+ return BCB_CMD_FIELD_TEST;
+ if (!strncmp(cmd, "store", sizeof("store")))
+ return BCB_CMD_STORE;
+ if (!strncmp(cmd, "dump", sizeof("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:
+ if (argc != 3)
+ goto err;
+ break;
+ 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 **field, int *size)
+{
+ if (!strncmp(name, "command", sizeof("command"))) {
+ *field = bcb.command;
+ *size = sizeof(bcb.command);
+ } else if (!strncmp(name, "status", sizeof("status"))) {
+ *field = bcb.status;
+ *size = sizeof(bcb.status);
+ } else if (!strncmp(name, "recovery", sizeof("recovery"))) {
+ *field = bcb.recovery;
+ *size = sizeof(bcb.recovery);
+ } else if (!strncmp(name, "stage", sizeof("stage"))) {
+ *field = bcb.stage;
+ *size = sizeof(bcb.stage);
+ } else if (!strncmp(name, "reserved", sizeof("reserved"))) {
+ *field = bcb.reserved;
+ *size = 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_1;
+
+ part = simple_strtoul(argv[2], &endp, 0);
+ if (*endp == '\0') {
+ ret = part_get_info(desc, part, &info);
+ if (ret)
+ goto err_1;
+ } else {
+ part = part_get_info_by_name(desc, argv[2], &info);
+ if (part < 0) {
+ ret = part;
+ goto err_1;
+ }
+ }
+
+ cnt = DIV_ROUND_UP(sizeof(struct bootloader_message), info.blksz);
+ if (cnt > info.size)
+ goto err_2;
+
+ if (blk_dread(desc, info.start, cnt, &bcb) != cnt) {
+ ret = -EIO;
+ goto err_1;
+ }
+
+ 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_1:
+ printf("Error: mmc %s:%s read failed (%d)\n", argv[1], argv[2], ret);
+ goto err;
+err_2:
+ 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"
+);