mips: mt76xx: gardena-smart-gateway: Add factory data variable handling

Some factory data is stored in the SPI NOR and needs to get extracted
from there into U-Boot environment variables.

This patch also includes a board-specific command "fd_write" to
provide some dummy / default values for this factory-data in the SPI
NOR flash. This should only be necessary for testing purposes though.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
diff --git a/board/gardena/smart-gateway-mt7688/board.c b/board/gardena/smart-gateway-mt7688/board.c
index 3a1838e..6e11077 100644
--- a/board/gardena/smart-gateway-mt7688/board.c
+++ b/board/gardena/smart-gateway-mt7688/board.c
@@ -4,11 +4,44 @@
  */
 
 #include <common.h>
+#include <environment.h>
 #include <led.h>
+#include <net.h>
+#include <spi.h>
+#include <spi_flash.h>
+#include <uuid.h>
+#include <linux/ctype.h>
 #include <linux/io.h>
 
 #define MT76XX_AGPIO_CFG	0x1000003c
 
+#define FACTORY_DATA_OFFS	0xc0000
+#define FACTORY_DATA_SECT_SIZE	0x10000
+#if ((CONFIG_ENV_OFFSET_REDUND + CONFIG_ENV_SIZE_REDUND) > FACTORY_DATA_OFFS)
+#error "U-Boot image with environment too big (overlapping with factory-data)!"
+#endif
+#define FACTORY_DATA_USER_OFFS	0x140
+#define FACTORY_DATA_SIZE	0x1f0
+#define FACTORY_DATA_CRC_LEN	(FACTORY_DATA_SIZE -			\
+				 FACTORY_DATA_USER_OFFS - sizeof(u32))
+
+#define FACTORY_DATA_MAGIC	0xCAFEBABE
+
+struct factory_data_values {
+	u8 pad_1[4];
+	u8 wifi_mac[6];		/* offs: 0x004: binary value */
+	u8 pad_2[30];
+	u8 eth_mac[6];		/* offs: 0x028: binary value */
+	u8 pad_3[FACTORY_DATA_USER_OFFS - 4 - 6 - 30 - 6];
+	/* User values start here at offset 0x140 */
+	u32 crc;
+	u32 magic;
+	u32 version;
+	char ipr_id[UUID_STR_LEN];	/* UUID as string w/o ending \0 */
+	char hqv_id[UUID_STR_LEN];	/* UUID as string w/o ending \0 */
+	char unielec_id[UUID_STR_LEN];	/* UUID as string w/o ending \0 */
+};
+
 int board_early_init_f(void)
 {
 	void __iomem *gpio_mode;
@@ -20,10 +53,246 @@
 	return 0;
 }
 
+static bool prepare_uuid_var(const char *fd_ptr, const char *env_var_name,
+			     char errorchar)
+{
+	char str[UUID_STR_LEN + 1] = { 0 };	/* Enough for UUID stuff */
+	bool env_updated = false;
+	char *env;
+	int i;
+
+	memcpy(str, fd_ptr, UUID_STR_LEN);
+
+	/* Convert non-ascii character to 'X' */
+	for (i = 0; i < UUID_STR_LEN; i++) {
+		if (!(isascii(str[i]) && isprint(str[i])))
+			str[i] = errorchar;
+	}
+
+	env = env_get(env_var_name);
+	if (strcmp(env, str)) {
+		env_set(env_var_name, str);
+		env_updated = true;
+	}
+
+	return env_updated;
+}
+
+static void factory_data_env_config(void)
+{
+	struct factory_data_values *fd;
+	struct spi_flash *sf;
+	int env_updated = 0;
+	char str[UUID_STR_LEN + 1];	/* Enough for UUID stuff */
+	char *env;
+	u8 *buf;
+	u32 crc;
+	int ret;
+	u8 *ptr;
+
+	buf = malloc(FACTORY_DATA_SIZE);
+	if (!buf) {
+		printf("F-Data:Unable to allocate buffer\n");
+		return;
+	}
+
+	/*
+	 * Get values from factory-data area in SPI NOR
+	 */
+	sf = spi_flash_probe(CONFIG_SF_DEFAULT_BUS,
+			     CONFIG_SF_DEFAULT_CS,
+			     CONFIG_SF_DEFAULT_SPEED,
+			     CONFIG_SF_DEFAULT_MODE);
+	if (!sf) {
+		printf("F-Data:Unable to access SPI NOR flash\n");
+		goto err_free;
+	}
+
+	ret = spi_flash_read(sf, FACTORY_DATA_OFFS, FACTORY_DATA_SIZE,
+			     (void *)buf);
+	if (ret) {
+		printf("F-Data:Unable to read factory-data from SPI NOR\n");
+		goto err_spi_flash;
+	}
+
+	fd = (struct factory_data_values *)buf;
+
+	if (fd->magic != FACTORY_DATA_MAGIC)
+		printf("F-Data:Magic value not correct\n");
+
+	crc = crc32(0, (u8 *)&fd->magic, FACTORY_DATA_CRC_LEN);
+	if (crc != fd->crc)
+		printf("F-Data:CRC not correct\n");
+	else
+		printf("F-Data:factory-data version %x detected\n",
+		       fd->version);
+
+	/* Handle wifi_mac env variable */
+	ptr = fd->wifi_mac;
+	sprintf(str, "%pM", ptr);
+	if (!is_valid_ethaddr(ptr))
+		printf("F-Data:Invalid MAC addr: wifi_mac %s\n", str);
+
+	env = env_get("wifiaddr");
+	if (strcmp(env, str)) {
+		env_set("wifiaddr", str);
+		env_updated = 1;
+	}
+
+	/* Handle eth_mac env variable */
+	ptr = fd->eth_mac;
+	sprintf(str, "%pM", ptr);
+	if (!is_valid_ethaddr(ptr))
+		printf("F-Data:Invalid MAC addr: eth_mac %s\n", str);
+
+	env = env_get("ethaddr");
+	if (strcmp(env, str)) {
+		env_set("ethaddr", str);
+		env_updated = 1;
+	}
+
+	/* Handle UUID env variables */
+	env_updated |= prepare_uuid_var(fd->ipr_id, "linuxmoduleid", 'X');
+	env_updated |= prepare_uuid_var(fd->hqv_id, "linuxmodulehqvid", '\0');
+	env_updated |= prepare_uuid_var(fd->unielec_id,
+					"linuxmoduleunielecid", '\0');
+
+	/* Check if the environment was updated and needs to get stored */
+	if (env_updated != 0) {
+		printf("F-Data:Values don't match env values -> saving\n");
+		env_save();
+	} else {
+		debug("F-Data:Values match current env values\n");
+	}
+
+err_spi_flash:
+	spi_flash_free(sf);
+
+err_free:
+	free(buf);
+}
+
 int board_late_init(void)
 {
 	if (IS_ENABLED(CONFIG_LED))
 		led_default_state();
 
+	factory_data_env_config();
+
 	return 0;
 }
+
+static void copy_or_generate_uuid(char *fd_ptr, const char *env_var_name)
+{
+	char str[UUID_STR_LEN + 1] = { 0 };	/* Enough for UUID stuff */
+	char *env;
+
+	/* Don't use the UUID dest place, as the \0 char won't fit */
+	env = env_get(env_var_name);
+	if (env)
+		strncpy(str, env, UUID_STR_LEN);
+	else
+		gen_rand_uuid_str(str, UUID_STR_FORMAT_STD);
+
+	memcpy(fd_ptr, str, UUID_STR_LEN);
+}
+
+/*
+ * Helper function to provide some sane factory-data values for testing
+ * purpose, when these values are not programmed correctly
+ */
+int do_fd_write(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
+{
+	struct factory_data_values *fd;
+	struct spi_flash *sf;
+	u8 *buf;
+	int ret = CMD_RET_FAILURE;
+
+	buf = malloc(FACTORY_DATA_SECT_SIZE);
+	if (!buf) {
+		printf("F-Data:Unable to allocate buffer\n");
+		return CMD_RET_FAILURE;
+	}
+
+	sf = spi_flash_probe(CONFIG_SF_DEFAULT_BUS,
+			     CONFIG_SF_DEFAULT_CS,
+			     CONFIG_SF_DEFAULT_SPEED,
+			     CONFIG_SF_DEFAULT_MODE);
+	if (!sf) {
+		printf("F-Data:Unable to access SPI NOR flash\n");
+		goto err_free;
+	}
+
+	/* Generate the factory-data struct */
+
+	/* Fist read complete sector into buffer */
+	ret = spi_flash_read(sf, FACTORY_DATA_OFFS, FACTORY_DATA_SECT_SIZE,
+			     (void *)buf);
+	if (ret) {
+		printf("F-Data:spi_flash_read failed (%d)\n", ret);
+		goto err_spi_flash;
+	}
+
+	fd = (struct factory_data_values *)buf;
+	fd->magic = FACTORY_DATA_MAGIC;
+	fd->version = 0x1;
+
+	/* Use existing MAC and UUID values or generate some random ones */
+	if (!eth_env_get_enetaddr("wifiaddr", fd->wifi_mac)) {
+		net_random_ethaddr(fd->wifi_mac);
+		/* to get a different seed value for the MAC address */
+		mdelay(10);
+	}
+
+	if (!eth_env_get_enetaddr("ethaddr", fd->eth_mac))
+		net_random_ethaddr(fd->eth_mac);
+
+	copy_or_generate_uuid(fd->ipr_id, "linuxmoduleid");
+	copy_or_generate_uuid(fd->hqv_id, "linuxmodulehqvid");
+	copy_or_generate_uuid(fd->unielec_id, "linuxmoduleunielecid");
+
+	printf("New factory-data values:\n");
+	printf("wifiaddr=%pM\n", fd->wifi_mac);
+	printf("ethaddr=%pM\n", fd->eth_mac);
+
+	/*
+	 * We don't have the \0 char at the end, so we need to specify the
+	 * length in the printf format instead
+	 */
+	printf("linuxmoduleid=%." __stringify(UUID_STR_LEN) "s\n", fd->ipr_id);
+	printf("linuxmodulehqvid=%." __stringify(UUID_STR_LEN) "s\n",
+	       fd->hqv_id);
+	printf("linuxmoduleunielecid=%." __stringify(UUID_STR_LEN) "s\n",
+	       fd->unielec_id);
+
+	fd->crc = crc32(0, (u8 *)&fd->magic, FACTORY_DATA_CRC_LEN);
+
+	ret = spi_flash_erase(sf, FACTORY_DATA_OFFS, FACTORY_DATA_SECT_SIZE);
+	if (ret) {
+		printf("F-Data:spi_flash_erase failed (%d)\n", ret);
+		goto err_spi_flash;
+	}
+
+	ret = spi_flash_write(sf, FACTORY_DATA_OFFS, FACTORY_DATA_SECT_SIZE,
+			      buf);
+	if (ret) {
+		printf("F-Data:spi_flash_write failed (%d)\n", ret);
+		goto err_spi_flash;
+	}
+
+	printf("F-Data:factory-data values written to SPI NOR flash\n");
+
+err_spi_flash:
+	spi_flash_free(sf);
+
+err_free:
+	free(buf);
+
+	return ret;
+}
+
+U_BOOT_CMD(
+	fd_write,	1,	0,	do_fd_write,
+	"Write test factory-data values to SPI NOR",
+	"\n"
+);