CBI: Add host command to set board info

This patch adds host command to write board information in EERPOM.

BUG=b:70294260
BRANCH=none
TEST=Run ectool cbi set <type> <value> to write BOARD_VERSION, OEM_ID,
and SKU_ID. Enable WP and verify cbi set command fails.

Change-Id: I39536d146313408ace666f350a107d89b331bf7a
Signed-off-by: Daisuke Nojiri <dnojiri@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/865570

3 files changed, 144 insertions, 2 deletions

diff --git a/common/cbi.c b/common/cbi.c
index b82d0375c2..41e8606487 100644
--- a/common/cbi.c
+++ b/common/cbi.c
@@ -9,12 +9,14 @@
 #include "console.h"
 #include "crc8.h"
 #include "cros_board_info.h"
+#include "gpio.h"
 #include "host_command.h"
 #include "i2c.h"
 #include "util.h"
 
 #define CPRINTS(format, args...) cprints(CC_SYSTEM, "CBI " format, ## args)
 
+#define EEPROM_PAGE_WRITE_SIZE	16
 static struct board_info bi;
 /* TODO: Init it to -1. On error (I2C or bad contents), retry a read and set it
  * to enum ec_error_list if it still fails. The successive calls can be
@@ -95,6 +97,38 @@ static int read_board_info(void)
 	return EC_SUCCESS;
 }
 
+static int eeprom_is_write_protected(void)
+{
+	return !gpio_get_level(GPIO_WP_L);
+}
+
+static int write_board_info(void)
+{
+	uint8_t buf[sizeof(bi) + 1];
+	/* The code is only tested for ST M24C02, whose page size for a single
+	 * write is 16 byte. To support different EEPROMs, you may need to
+	 * craft the i2c packets accordingly. */
+	_Static_assert(sizeof(bi) <= EEPROM_PAGE_WRITE_SIZE,
+		       "struct board_info exceeds page write size");
+	int rv;
+
+	if (eeprom_is_write_protected()) {
+		CPRINTS("Failed to write for WP");
+		return EC_ERROR_ACCESS_DENIED;
+	}
+
+	buf[0] = 0;	/* Offset 0 */
+	memcpy(&buf[1], &bi, sizeof(bi));
+	rv = i2c_xfer(I2C_PORT_EEPROM, I2C_ADDR_EEPROM, buf,
+		     sizeof(bi) + 1, NULL, 0, I2C_XFER_SINGLE);
+	if (rv) {
+		CPRINTS("Failed to write for %d", rv);
+		return rv;
+	}
+
+	return EC_SUCCESS;
+}
+
 int cbi_get_board_version(uint32_t *version)
 {
 	if (read_board_info())
@@ -154,3 +188,56 @@ static int hc_cbi_get(struct host_cmd_handler_args *args)
 DECLARE_HOST_COMMAND(EC_CMD_GET_CROS_BOARD_INFO,
 		     hc_cbi_get,
 		     EC_VER_MASK(0));
+
+static int hc_cbi_set(struct host_cmd_handler_args *args)
+{
+	const struct __ec_align4 ec_params_set_cbi *p = args->params;
+
+	if (p->flag & CBI_SET_INIT) {
+		memset(&bi, 0, sizeof(bi));
+		memcpy(&bi.head.magic, cbi_magic, sizeof(cbi_magic));
+		initialized = 1;
+	} else {
+		if (read_board_info())
+			return EC_RES_ERROR;
+	}
+
+	switch (p->type) {
+	case CBI_DATA_BOARD_VERSION:
+		if (p->data > UINT16_MAX)
+			return EC_RES_INVALID_PARAM;
+		bi.version = p->data;
+		break;
+	case CBI_DATA_OEM_ID:
+		if (p->data > UINT8_MAX)
+			return EC_RES_INVALID_PARAM;
+		bi.oem_id = p->data;
+		break;
+	case CBI_DATA_SKU_ID:
+		if (p->data > UINT8_MAX)
+			return EC_RES_INVALID_PARAM;
+		bi.sku_id = p->data;
+		break;
+	default:
+		return EC_RES_INVALID_PARAM;
+	}
+
+	/* Whether we're modifying existing data or creating new one,
+	 * we take over the format. */
+	bi.head.major_version = CBI_VERSION_MAJOR;
+	bi.head.minor_version = CBI_VERSION_MINOR;
+	bi.head.total_size = sizeof(bi);
+	bi.head.crc = cbi_crc8(&bi);
+
+	/* Skip write if client asks so. */
+	if (p->flag & CBI_SET_NO_SYNC)
+		return EC_RES_SUCCESS;
+
+	if (write_board_info())
+		return EC_RES_ERROR;
+
+	return EC_RES_SUCCESS;
+}
+DECLARE_HOST_COMMAND(EC_CMD_SET_CROS_BOARD_INFO,
+		     hc_cbi_set,
+		     EC_VER_MASK(0));
diff --git a/include/ec_commands.h b/include/ec_commands.h
index 23307354e1..705e54f2b1 100644
--- a/include/ec_commands.h
+++ b/include/ec_commands.h
@@ -4576,6 +4576,11 @@ struct __ec_align1 ec_params_efs_verify {
  * size to determine how big it is.
  */
 #define EC_CMD_GET_CROS_BOARD_INFO	0x011F
+/*
+ * Write info into Cros Board Info on EEPROM. Write fails if the board has
+ * hardware write-protect enabled.
+ */
+#define EC_CMD_SET_CROS_BOARD_INFO	0x0120
 
 enum cbi_data_type {
 	/* integer types */
@@ -4591,6 +4596,24 @@ struct __ec_align4 ec_params_get_cbi {
 	uint32_t type;		/* enum cbi_data_type */
 };
 
+/*
+ * Flags to control write behavior.
+ *
+ * NO_SYNC: Makes EC update data in RAM but skip writing to EEPROM. It's
+ *          useful when writing multiple fields in a row.
+ * INIT:    Need to be set when creating a new CBI from scratch. All fields
+ *          will be initialized to zero first.
+ */
+#define CBI_SET_NO_SYNC		(1 << 0)
+#define CBI_SET_INIT		(1 << 1)
+
+struct __ec_align1 ec_params_set_cbi {
+	uint32_t type;		/* enum cbi_data_type */
+	uint8_t flag;		/* CBI_SET_* */
+	uint32_t data;		/* For numeric value */
+	uint8_t raw[];		/* For string and raw data */
+};
+
 /*****************************************************************************/
 /* The command range 0x200-0x2FF is reserved for Rotor. */
 
diff --git a/util/ectool.c b/util/ectool.c
index c694e83c56..4737ac91e3 100644
--- a/util/ectool.c
+++ b/util/ectool.c
@@ -60,7 +60,7 @@ const char help_str[] =
 	"  boardversion\n"
 	"      Prints the board version\n"
 	"  cbi\n"
-	"      Get Cros Board Info\n"
+	"      Get/Set Cros Board Info\n"
 	"  chargecurrentlimit\n"
 	"      Set the maximum battery charging current\n"
 	"  chargecontrol\n"
@@ -6231,10 +6231,14 @@ static void cmd_cbi_help(char *cmd)
 {
 	fprintf(stderr,
 		"  Usage: %s get <type>\n"
+		"  Usage: %s set <type> value [flag]\n"
 		"    <type> is one of:\n"
 		"      0: BOARD_VERSION\n"
 		"      1: OEM_ID\n"
-		"      2: SKU_ID\n", cmd);
+		"      2: SKU_ID\n"
+		"    [flag] is combination of:\n"
+		"      01b: Skip write to EEPROM. Use for back-to-back writes\n"
+		"      10b: Set all fields to defaults first\n", cmd, cmd);
 }
 
 /*
@@ -6282,6 +6286,34 @@ static int cmd_cbi(int argc, char *argv[])
 			return -1;
 		}
 		return 0;
+	} else if (!strcasecmp(argv[1], "set")) {
+		struct ec_params_set_cbi p;
+		if (argc < 4) {
+			fprintf(stderr, "Invalid number of params\n");
+			cmd_cbi_help(argv[0]);
+			return -1;
+		}
+		memset(&p, 0, sizeof(p));
+		p.type = type;
+		p.data = strtol(argv[3], &e, 0);
+		if (e && *e) {
+			fprintf(stderr, "Bad value\n");
+			return -1;
+		}
+		if (argc > 4) {
+			p.flag = strtol(argv[4], &e, 0);
+			if (e && *e) {
+				fprintf(stderr, "Bad flag\n");
+				return -1;
+			}
+		}
+		rv = ec_command(EC_CMD_SET_CROS_BOARD_INFO, 0, &p, sizeof(p),
+				NULL, 0);
+		if (rv < 0) {
+			fprintf(stderr, "Error code: %d\n", rv);
+			return rv;
+		}
+		return 0;
 	}
 
 	fprintf(stderr, "Invalid sub command: %s\n", argv[1]);