drivers/vpd: Add VPD support

VPD reference: https://chromium.googlesource.com/chromiumos/platform/vpd/+/master/README.md

Copy ChromeOS VPD driver to add support for VPD without CROMEOS.
Possible use case:
* Storing calibration data
* Storing MAC address
* Storing serial
* Storing boot options

+ Now it's possible to define the VPD space by choosing
  one of the following enums: VPD_ANY, VPD_RW, VPD_RO.
+ CHROMEOS selects now VPD as part of it.
+ VPD is implemented as driver.

Change-Id: Id9263bd39bf25d024e93daa57053fefcb1adc53a
Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com>
Reviewed-on: https://review.coreboot.org/25046
Reviewed-by: David Hendricks <david.hendricks@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/drivers/vpd/Kconfig

@@ -0,0 +1,28 @@
+##
+## This file is part of the coreboot project.
+##
+## Copyright (C) 2012 The Chromium OS Authors.  All rights reserved.
+##
+## This program is free software; you can redistribute it and/or modify
+## it under the terms of the GNU General Public License as published by
+## the Free Software Foundation; version 2 of the License.
+##
+## This program is distributed in the hope that it will be useful,
+## but WITHOUT ANY WARRANTY; without even the implied warranty of
+## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+## GNU General Public License for more details.
+##
+
+config VPD
+	bool "Support for Vital Product Data tables"
+	default n
+	help
+	  Enable support for flash based vital product data.
+
+if VPD
+
+config VPD_DEBUG
+	bool "Enable VPD debug output"
+	default n
+
+endif

src/drivers/vpd/Makefile.inc

@@ -0,0 +1,2 @@
+romstage-$(CONFIG_VPD) += lib_vpd.c
+ramstage-$(CONFIG_VPD) += vpd.c lib_vpd.c

src/drivers/vpd/lib_vpd.c

@@ -0,0 +1,113 @@
+/*
+ * Copyright (c) 2014 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ *
+ */
+#include <assert.h>
+#include "lib_vpd.h"
+
+/* Given an encoded string, this functions decodes the length field which varies
+ * from 1 byte to many bytes.
+ *
+ * The in points the actual byte going to be decoded. The *length returns
+ * the decoded length field. The number of consumed bytes will be stroed in
+ * decoded_len.
+ *
+ * Returns VPD_FAIL if more bit is 1, but actually reaches the end of string.
+ */
+int decodeLen(const int32_t max_len,
+	      const uint8_t *in,
+	      int32_t *length,
+	      int32_t *decoded_len)
+{
+	uint8_t more;
+	int i = 0;
+
+	assert(length);
+	assert(decoded_len);
+
+	*length = 0;
+	do {
+		if (i >= max_len)
+			return VPD_FAIL;
+
+		more = in[i] & 0x80;
+		*length <<= 7;
+		*length |= in[i] & 0x7f;
+		++i;
+	} while (more);
+
+	*decoded_len = i;
+
+	return VPD_OK;
+}
+
+/* Given the encoded string, this function invokes callback with extracted
+ * (key, value). The *consumed will be plused the number of bytes consumed in
+ * this function.
+ *
+ * The input_buf points to the first byte of the input buffer.
+ *
+ * The *consumed starts from 0, which is actually the next byte to be decoded.
+ * It can be non-zero to be used in multiple calls.
+ *
+ * If one entry is successfully decoded, sends it to callback and returns the
+ * result.
+ */
+int decodeVpdString(const int32_t max_len,
+		    const uint8_t *input_buf,
+		    int32_t *consumed,
+		    VpdDecodeCallback callback,
+		    void *callback_arg)
+{
+	int type;
+	int32_t key_len, value_len;
+	int32_t decoded_len;
+	const uint8_t *key, *value;
+
+	/* type */
+	if (*consumed >= max_len)
+		return VPD_FAIL;
+
+	type = input_buf[*consumed];
+	switch (type) {
+	case VPD_TYPE_INFO:
+	case VPD_TYPE_STRING:
+		(*consumed)++;
+		/* key */
+		if (VPD_OK != decodeLen(max_len - *consumed,
+					&input_buf[*consumed], &key_len,
+					&decoded_len) ||
+				*consumed + decoded_len >= max_len) {
+				return VPD_FAIL;
+		}
+
+		*consumed += decoded_len;
+		key = &input_buf[*consumed];
+		*consumed += key_len;
+
+		/* value */
+		if (VPD_OK != decodeLen(max_len - *consumed,
+					&input_buf[*consumed],
+					&value_len, &decoded_len) ||
+					*consumed + decoded_len > max_len) {
+					return VPD_FAIL;
+		}
+		*consumed += decoded_len;
+		value = &input_buf[*consumed];
+		*consumed += value_len;
+
+		if (type == VPD_TYPE_STRING)
+			return callback(key, key_len, value, value_len,
+					callback_arg);
+
+		return VPD_OK;
+
+	default:
+		return VPD_FAIL;
+	break;
+	}
+
+	return VPD_OK;
+}

src/drivers/vpd/vpd.c

@@ -5,14 +5,13 @@
  */
 
 #include <console/console.h>
-
 #include <cbmem.h>
 #include <fmap.h>
 #include <stdlib.h>
 #include <string.h>
 #include <timestamp.h>
 
-#include "cros_vpd.h"
+#include "vpd.h"
 #include "lib_vpd.h"
 #include "vpd_tables.h"
 
@@ -178,7 +177,7 @@ static int vpd_gets_callback(const uint8_t *key, int32_t key_len,
 	return VPD_FAIL;
 }
 
-const void *cros_vpd_find(const char *key, int *size)
+const void *vpd_find(const char *key, int *size, enum vpd_region region)
 {
 	struct vpd_gets_arg arg = {0};
 	int consumed = 0;
@@ -191,7 +190,15 @@ const void *cros_vpd_find(const char *key, int *size)
 	arg.key = (const uint8_t *)key;
 	arg.key_len = strlen(key);
 
-	while (VPD_OK == decodeVpdString(vpd->ro_size, vpd->blob, &consumed,
+	if (region == VPD_ANY || region == VPD_RO)
+		while (VPD_OK == decodeVpdString(vpd->ro_size, vpd->blob,
+		       &consumed, vpd_gets_callback, &arg)) {
+		/* Iterate until found or no more entries. */
+		}
+
+	if (!arg.matched && region != VPD_RO)
+		while (VPD_OK == decodeVpdString(vpd->rw_size,
+		       vpd->blob + vpd->ro_size, &consumed,
 		       vpd_gets_callback, &arg)) {
 		/* Iterate until found or no more entries. */
 		}
@@ -203,12 +210,12 @@ const void *cros_vpd_find(const char *key, int *size)
 	return arg.value;
 }
 
-char *cros_vpd_gets(const char *key, char *buffer, int size)
+char *vpd_gets(const char *key, char *buffer, int size, enum vpd_region region)
 {
 	const void *string_address;
 	int string_size;
 
-	string_address = cros_vpd_find(key, &string_size);
+	string_address = vpd_find(key, &string_size, region);
 
 	if (!string_address)
 		return NULL;

src/drivers/vpd/vpd.h

@@ -4,12 +4,14 @@
  * found in the LICENSE file.
  */
 
-#ifndef __CROS_VPD_H__
-#define __CROS_VPD_H__
-
-#define CROS_VPD_REGION_NAME "region"
-#define CROS_VPD_WIFI_SAR_NAME "wifi_sar"
+#ifndef __VPD_H__
+#define __VPD_H__
 
+enum vpd_region {
+	VPD_ANY = 0,
+	VPD_RO = 1,
+	VPD_RW = 2
+};
 /*
  * Reads VPD string value by key.
  *
@@ -19,7 +21,7 @@
  *
  * Returns NULL if key is not found, otherwise buffer.
  */
-char *cros_vpd_gets(const char *key, char *buffer, int size);
+char *vpd_gets(const char *key, char *buffer, int size, enum vpd_region region);
 
 /*
  * Find VPD value by key.
@@ -35,6 +37,6 @@ char *cros_vpd_gets(const char *key, char *buffer, int size);
  * Returns NULL if key is not found.
  */
 
-const void *cros_vpd_find(const char *key, int *size);
+const void *vpd_find(const char *key, int *size, enum vpd_region region);
 
-#endif  /* __CROS_VPD_H__ */
+#endif  /* __VPD_H__ */

src/mainboard/google/reef/variants/snappy/mainboard.c

@@ -16,7 +16,7 @@
 #include <string.h>
 #include <baseboard/variants.h>
 #include <ec/google/chromeec/ec.h>
-#include <vendorcode/google/chromeos/cros_vpd.h>
+#include <drivers/vpd/vpd.h>
 #include <soc/cpu.h>
 #include <soc/intel/apollolake/chip.h>
 
@@ -59,7 +59,7 @@ uint8_t variant_board_sku(void)
 	if (!IS_ENABLED(CONFIG_CHROMEOS))
 		return board_sku_num;
 
-	if (!cros_vpd_gets(vpd_skuid, vpd_buffer, ARRAY_SIZE(vpd_buffer)))
+	if (!vpd_gets(vpd_skuid, vpd_buffer, ARRAY_SIZE(vpd_buffer), VPD_ANY))
 		return board_sku_num;
 
 	vpd_len = strlen(vpd_buffer);

src/vendorcode/google/chromeos/Kconfig

@@ -24,6 +24,7 @@ config CHROMEOS
 	select ELOG if BOOT_DEVICE_SUPPORTS_WRITES
 	select COLLECT_TIMESTAMPS
 	select VBOOT
+	select VPD
 	help
 	  Enable ChromeOS specific features like the GPIO sub table in
 	  the coreboot table. NOTE: Enabling this option on an unsupported

src/vendorcode/google/chromeos/Makefile.inc

@@ -17,8 +17,7 @@ ramstage-$(CONFIG_ELOG) += elog.c
 ramstage-$(CONFIG_HAVE_ACPI_TABLES) += gnvs.c
 ramstage-$(CONFIG_HAVE_ACPI_TABLES) += acpi.c
 ramstage-$(CONFIG_CHROMEOS_RAMOOPS) += ramoops.c
-romstage-y += vpd_decode.c
-ramstage-y += vpd_decode.c cros_vpd.c vpd_mac.c vpd_serialno.c vpd_calibration.c
+ramstage-y += vpd_mac.c vpd_serialno.c vpd_calibration.c
 ramstage-$(CONFIG_CHROMEOS_DISABLE_PLATFORM_HIERARCHY_ON_RESUME) += tpm2.c
 ramstage-$(CONFIG_HAVE_REGULATORY_DOMAIN) += wrdd.c
 ramstage-$(CONFIG_USE_SAR) += sar.c

src/vendorcode/google/chromeos/sar.c

@@ -19,9 +19,10 @@
 #include <types.h>
 #include <string.h>
 #include <sar.h>
-#include "cros_vpd.h"
+#include <drivers/vpd/vpd.h>
 
 #define WIFI_SAR_CBFS_FILENAME	"wifi_sar_defaults.hex"
+#define CROS_VPD_WIFI_SAR_NAME	"wifi_sar"
 
 static int load_sar_file_from_cbfs(void *buf, size_t buffer_size)
 {
@@ -55,7 +56,7 @@ For [WGDS_VERSION] 0x00,
 int get_wifi_sar_limits(struct wifi_sar_limits *sar_limits)
 {
 	const char *wifi_sar_limit_key = CROS_VPD_WIFI_SAR_NAME;
-	/* cros_vpd_gets() reads in one less than size characters from the VPD
+	/* vpd_gets() reads in one less than size characters from the VPD
 	 * with a terminating null byte ('\0') stored as the last character into
 	 * the buffer, thus the increasing by 1 for buffer_size. */
 	const size_t buffer_size = (sizeof(struct wifi_sar_limits) /
@@ -79,8 +80,8 @@ int get_wifi_sar_limits(struct wifi_sar_limits *sar_limits)
 	}
 
 	/* Try to read the SAR limit entry from VPD */
-	if (!cros_vpd_gets(wifi_sar_limit_key, wifi_sar_limit_str,
-							 buffer_size)) {
+	if (!vpd_gets(wifi_sar_limit_key, wifi_sar_limit_str,
+							 buffer_size, VPD_ANY)) {
 		printk(BIOS_ERR, "Error: Could not locate '%s' in VPD.\n",
 				wifi_sar_limit_key);
 

src/vendorcode/google/chromeos/vpd_calibration.c

@@ -19,7 +19,7 @@
 #include <string.h>
 
 #include <vendorcode/google/chromeos/chromeos.h>
-#include <vendorcode/google/chromeos/cros_vpd.h>
+#include <drivers/vpd/vpd.h>
 
 /*
  * This file provides functions looking in the VPD for WiFi calibration data,
@@ -112,7 +112,7 @@ static size_t fill_up_entries_cache(struct vpd_blob_cache_t *cache,
 			strcpy(cache->key_name, templates[i]);
 			cache->key_name[index_location] = j + '0';
 
-			payload = cros_vpd_find(cache->key_name, &payload_size);
+			payload = vpd_find(cache->key_name, &payload_size, VPD_ANY);
 			if (!payload)
 				continue;
 

src/vendorcode/google/chromeos/vpd_decode.c

@@ -1,89 +0,0 @@
-/*
- * Copyright (c) 2014 The Chromium OS Authors. All rights reserved.
- * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- *
- */
-#include <assert.h>
-#include "lib_vpd.h"
-
-int decodeLen(
-    const int32_t max_len,
-    const uint8_t *in,
-    int32_t *length,
-    int32_t *decoded_len) {
-  uint8_t more;
-  int i = 0;
-
-  assert(length);
-  assert(decoded_len);
-
-  *length = 0;
-  do {
-    if (i >= max_len) return VPD_FAIL;
-    more = in[i] & 0x80;
-    *length <<= 7;
-    *length |= in[i] & 0x7f;
-    ++i;
-  } while (more);
-
-  *decoded_len = i;
-
-  return VPD_OK;
-}
-
-/* Sequentially decodes type, key, and value.
- */
-int decodeVpdString(
-    const int32_t max_len,
-    const uint8_t *input_buf,
-    int32_t *consumed,
-    VpdDecodeCallback callback,
-    void *callback_arg) {
-  int type;
-  int32_t key_len, value_len;
-  int32_t decoded_len;
-  const uint8_t *key, *value;
-
-  /* type */
-  if (*consumed >= max_len)
-    return VPD_FAIL;
-
-  type = input_buf[*consumed];
-  switch (type) {
-    case VPD_TYPE_INFO:
-    case VPD_TYPE_STRING:
-      (*consumed)++;
-
-      /* key */
-      if (VPD_OK != decodeLen(max_len - *consumed, &input_buf[*consumed],
-                              &key_len, &decoded_len) ||
-          *consumed + decoded_len >= max_len) {
-        return VPD_FAIL;
-      }
-
-      *consumed += decoded_len;
-      key = &input_buf[*consumed];
-      *consumed += key_len;
-
-      /* value */
-      if (VPD_OK != decodeLen(max_len - *consumed, &input_buf[*consumed],
-                              &value_len, &decoded_len) ||
-          *consumed + decoded_len > max_len) {
-        return VPD_FAIL;
-      }
-      *consumed += decoded_len;
-      value = &input_buf[*consumed];
-      *consumed += value_len;
-
-      if (type == VPD_TYPE_STRING)
-        return callback(key, key_len, value, value_len, callback_arg);
-
-      return VPD_OK;
-
-    default:
-      return VPD_FAIL;
-      break;
-  }
-  return VPD_OK;
-}

src/vendorcode/google/chromeos/vpd_mac.c

@@ -17,7 +17,7 @@
 #include <console/console.h>
 #include <string.h>
 
-#include <vendorcode/google/chromeos/cros_vpd.h>
+#include <drivers/vpd/vpd.h>
 
 /*
  * Decode string representation of the MAC address (a string of 12 hex
@@ -84,8 +84,8 @@ void lb_table_add_macs_from_vpd(struct lb_header *header)
 			 * If there are no more MAC addresses of this template
 			 * in the VPD - move on.
 			 */
-			if (!cros_vpd_gets(mac_addr_key, mac_addr_str,
-					   sizeof(mac_addr_str)))
+			if (!vpd_gets(mac_addr_key, mac_addr_str,
+					   sizeof(mac_addr_str), VPD_ANY))
 				break;
 
 			if (!macs) {

src/vendorcode/google/chromeos/vpd_serialno.c

@@ -18,7 +18,7 @@
 #include <assert.h>
 #include <string.h>
 
-#include <vendorcode/google/chromeos/cros_vpd.h>
+#include <drivers/vpd/vpd.h>
 
 void lb_table_add_serialno_from_vpd(struct lb_header *header)
 {
@@ -27,8 +27,8 @@ void lb_table_add_serialno_from_vpd(struct lb_header *header)
 	char serialno[32];
 	size_t len;
 
-	if (!cros_vpd_gets(serialno_key, serialno,
-				sizeof(serialno))) {
+	if (!vpd_gets(serialno_key, serialno,
+				sizeof(serialno), VPD_ANY)) {
 		printk(BIOS_ERR, "no serial number in vpd\n");
 		return;
 	}

src/vendorcode/google/chromeos/wrdd.c

@@ -18,7 +18,9 @@
 #include <types.h>
 #include <string.h>
 #include <wrdd.h>
-#include "cros_vpd.h"
+#include <drivers/vpd/vpd.h>
+
+#define CROS_VPD_REGION_NAME	"region"
 
 /*
  * wrdd_domain_value is ISO 3166-2
@@ -59,8 +61,8 @@ uint16_t wifi_regulatory_domain(void)
 	char *separator;
 
 	/* If not found for any reason fall backto the default value */
-	if (!cros_vpd_gets(wrdd_domain_key, wrdd_domain_code,
-		ARRAY_SIZE(wrdd_domain_code))) {
+	if (!vpd_gets(wrdd_domain_key, wrdd_domain_code,
+		ARRAY_SIZE(wrdd_domain_code), VPD_ANY)) {
 		printk(BIOS_DEBUG,
 		"Error: Could not locate '%s' in VPD\n", wrdd_domain_key);
 		return WRDD_DEFAULT_REGULATORY_DOMAIN;