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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * ONIE tlv NVMEM cells provider4 *5 * Copyright (C) 2022 Open Compute Group ONIE6 * Author: Miquel Raynal <miquel.raynal@bootlin.com>7 * Based on the nvmem driver written by: Vadym Kochan <vadym.kochan@plvision.eu>8 * Inspired by the first layout written by: Rafał Miłecki <rafal@milecki.pl>9 */10 11#include <linux/crc32.h>12#include <linux/etherdevice.h>13#include <linux/nvmem-consumer.h>14#include <linux/nvmem-provider.h>15#include <linux/of.h>16 17#define ONIE_TLV_MAX_LEN 204818#define ONIE_TLV_CRC_FIELD_SZ 619#define ONIE_TLV_CRC_SZ 420#define ONIE_TLV_HDR_ID "TlvInfo"21 22struct onie_tlv_hdr {23 u8 id[8];24 u8 version;25 __be16 data_len;26} __packed;27 28struct onie_tlv {29 u8 type;30 u8 len;31} __packed;32 33static const char *onie_tlv_cell_name(u8 type)34{35 switch (type) {36 case 0x21:37 return "product-name";38 case 0x22:39 return "part-number";40 case 0x23:41 return "serial-number";42 case 0x24:43 return "mac-address";44 case 0x25:45 return "manufacture-date";46 case 0x26:47 return "device-version";48 case 0x27:49 return "label-revision";50 case 0x28:51 return "platform-name";52 case 0x29:53 return "onie-version";54 case 0x2A:55 return "num-macs";56 case 0x2B:57 return "manufacturer";58 case 0x2C:59 return "country-code";60 case 0x2D:61 return "vendor";62 case 0x2E:63 return "diag-version";64 case 0x2F:65 return "service-tag";66 case 0xFD:67 return "vendor-extension";68 case 0xFE:69 return "crc32";70 default:71 break;72 }73 74 return NULL;75}76 77static int onie_tlv_mac_read_cb(void *priv, const char *id, int index,78 unsigned int offset, void *buf,79 size_t bytes)80{81 eth_addr_add(buf, index);82 83 return 0;84}85 86static nvmem_cell_post_process_t onie_tlv_read_cb(u8 type, u8 *buf)87{88 switch (type) {89 case 0x24:90 return &onie_tlv_mac_read_cb;91 default:92 break;93 }94 95 return NULL;96}97 98static int onie_tlv_add_cells(struct device *dev, struct nvmem_device *nvmem,99 size_t data_len, u8 *data)100{101 struct nvmem_cell_info cell = {};102 struct device_node *layout;103 struct onie_tlv tlv;104 unsigned int hdr_len = sizeof(struct onie_tlv_hdr);105 unsigned int offset = 0;106 int ret;107 108 layout = of_nvmem_layout_get_container(nvmem);109 if (!layout)110 return -ENOENT;111 112 while (offset < data_len) {113 memcpy(&tlv, data + offset, sizeof(tlv));114 if (offset + tlv.len >= data_len) {115 dev_err(dev, "Out of bounds field (0x%x bytes at 0x%x)\n",116 tlv.len, hdr_len + offset);117 break;118 }119 120 cell.name = onie_tlv_cell_name(tlv.type);121 if (!cell.name)122 continue;123 124 cell.offset = hdr_len + offset + sizeof(tlv.type) + sizeof(tlv.len);125 cell.bytes = tlv.len;126 cell.np = of_get_child_by_name(layout, cell.name);127 cell.read_post_process = onie_tlv_read_cb(tlv.type, data + offset + sizeof(tlv));128 129 ret = nvmem_add_one_cell(nvmem, &cell);130 if (ret) {131 of_node_put(layout);132 return ret;133 }134 135 offset += sizeof(tlv) + tlv.len;136 }137 138 of_node_put(layout);139 140 return 0;141}142 143static bool onie_tlv_hdr_is_valid(struct device *dev, struct onie_tlv_hdr *hdr)144{145 if (memcmp(hdr->id, ONIE_TLV_HDR_ID, sizeof(hdr->id))) {146 dev_err(dev, "Invalid header\n");147 return false;148 }149 150 if (hdr->version != 0x1) {151 dev_err(dev, "Invalid version number\n");152 return false;153 }154 155 return true;156}157 158static bool onie_tlv_crc_is_valid(struct device *dev, size_t table_len, u8 *table)159{160 struct onie_tlv crc_hdr;161 u32 read_crc, calc_crc;162 __be32 crc_be;163 164 memcpy(&crc_hdr, table + table_len - ONIE_TLV_CRC_FIELD_SZ, sizeof(crc_hdr));165 if (crc_hdr.type != 0xfe || crc_hdr.len != ONIE_TLV_CRC_SZ) {166 dev_err(dev, "Invalid CRC field\n");167 return false;168 }169 170 /* The table contains a JAMCRC, which is XOR'ed compared to the original171 * CRC32 implementation as known in the Ethernet world.172 */173 memcpy(&crc_be, table + table_len - ONIE_TLV_CRC_SZ, ONIE_TLV_CRC_SZ);174 read_crc = be32_to_cpu(crc_be);175 calc_crc = crc32(~0, table, table_len - ONIE_TLV_CRC_SZ) ^ 0xFFFFFFFF;176 if (read_crc != calc_crc) {177 dev_err(dev, "Invalid CRC read: 0x%08x, expected: 0x%08x\n",178 read_crc, calc_crc);179 return false;180 }181 182 return true;183}184 185static int onie_tlv_parse_table(struct nvmem_layout *layout)186{187 struct nvmem_device *nvmem = layout->nvmem;188 struct device *dev = &layout->dev;189 struct onie_tlv_hdr hdr;190 size_t table_len, data_len, hdr_len;191 u8 *table, *data;192 int ret;193 194 ret = nvmem_device_read(nvmem, 0, sizeof(hdr), &hdr);195 if (ret < 0)196 return ret;197 198 if (!onie_tlv_hdr_is_valid(dev, &hdr)) {199 dev_err(dev, "Invalid ONIE TLV header\n");200 return -EINVAL;201 }202 203 hdr_len = sizeof(hdr.id) + sizeof(hdr.version) + sizeof(hdr.data_len);204 data_len = be16_to_cpu(hdr.data_len);205 table_len = hdr_len + data_len;206 if (table_len > ONIE_TLV_MAX_LEN) {207 dev_err(dev, "Invalid ONIE TLV data length\n");208 return -EINVAL;209 }210 211 table = devm_kmalloc(dev, table_len, GFP_KERNEL);212 if (!table)213 return -ENOMEM;214 215 ret = nvmem_device_read(nvmem, 0, table_len, table);216 if (ret != table_len)217 return ret;218 219 if (!onie_tlv_crc_is_valid(dev, table_len, table))220 return -EINVAL;221 222 data = table + hdr_len;223 ret = onie_tlv_add_cells(dev, nvmem, data_len, data);224 if (ret)225 return ret;226 227 return 0;228}229 230static int onie_tlv_probe(struct nvmem_layout *layout)231{232 layout->add_cells = onie_tlv_parse_table;233 234 return nvmem_layout_register(layout);235}236 237static void onie_tlv_remove(struct nvmem_layout *layout)238{239 nvmem_layout_unregister(layout);240}241 242static const struct of_device_id onie_tlv_of_match_table[] = {243 { .compatible = "onie,tlv-layout", },244 {},245};246MODULE_DEVICE_TABLE(of, onie_tlv_of_match_table);247 248static struct nvmem_layout_driver onie_tlv_layout = {249 .driver = {250 .name = "onie-tlv-layout",251 .of_match_table = onie_tlv_of_match_table,252 },253 .probe = onie_tlv_probe,254 .remove = onie_tlv_remove,255};256module_nvmem_layout_driver(onie_tlv_layout);257 258MODULE_LICENSE("GPL");259MODULE_AUTHOR("Miquel Raynal <miquel.raynal@bootlin.com>");260MODULE_DESCRIPTION("NVMEM layout driver for Onie TLV table parsing");261