1 // SPDX-License-Identifier: GPL-2.0-only
3 * ONIE tlv NVMEM cells provider
5 * Copyright (C) 2022 Open Compute Group ONIE
6 * 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>
11 #include <linux/crc32.h>
12 #include <linux/etherdevice.h>
13 #include <linux/nvmem-consumer.h>
14 #include <linux/nvmem-provider.h>
17 #define ONIE_TLV_MAX_LEN 2048
18 #define ONIE_TLV_CRC_FIELD_SZ 6
19 #define ONIE_TLV_CRC_SZ 4
20 #define ONIE_TLV_HDR_ID "TlvInfo"
33 static const char *onie_tlv_cell_name(u8 type)
37 return "product-name";
41 return "serial-number";
45 return "manufacture-date";
47 return "device-version";
49 return "label-revision";
51 return "platform-name";
53 return "onie-version";
57 return "manufacturer";
59 return "country-code";
63 return "diag-version";
67 return "vendor-extension";
77 static int onie_tlv_mac_read_cb(void *priv, const char *id, int index,
78 unsigned int offset, void *buf,
81 eth_addr_add(buf, index);
86 static nvmem_cell_post_process_t onie_tlv_read_cb(u8 type, u8 *buf)
90 return &onie_tlv_mac_read_cb;
98 static int onie_tlv_add_cells(struct device *dev, struct nvmem_device *nvmem,
99 size_t data_len, u8 *data)
101 struct nvmem_cell_info cell = {};
102 struct device_node *layout;
104 unsigned int hdr_len = sizeof(struct onie_tlv_hdr);
105 unsigned int offset = 0;
108 layout = of_nvmem_layout_get_container(nvmem);
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);
120 cell.name = onie_tlv_cell_name(tlv.type);
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));
129 ret = nvmem_add_one_cell(nvmem, &cell);
135 offset += sizeof(tlv) + tlv.len;
143 static bool onie_tlv_hdr_is_valid(struct device *dev, struct onie_tlv_hdr *hdr)
145 if (memcmp(hdr->id, ONIE_TLV_HDR_ID, sizeof(hdr->id))) {
146 dev_err(dev, "Invalid header\n");
150 if (hdr->version != 0x1) {
151 dev_err(dev, "Invalid version number\n");
158 static bool onie_tlv_crc_is_valid(struct device *dev, size_t table_len, u8 *table)
160 struct onie_tlv crc_hdr;
161 u32 read_crc, calc_crc;
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");
170 /* The table contains a JAMCRC, which is XOR'ed compared to the original
171 * CRC32 implementation as known in the Ethernet world.
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",
185 static int onie_tlv_parse_table(struct nvmem_layout *layout)
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;
194 ret = nvmem_device_read(nvmem, 0, sizeof(hdr), &hdr);
198 if (!onie_tlv_hdr_is_valid(dev, &hdr)) {
199 dev_err(dev, "Invalid ONIE TLV header\n");
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");
211 table = devm_kmalloc(dev, table_len, GFP_KERNEL);
215 ret = nvmem_device_read(nvmem, 0, table_len, table);
216 if (ret != table_len)
219 if (!onie_tlv_crc_is_valid(dev, table_len, table))
222 data = table + hdr_len;
223 ret = onie_tlv_add_cells(dev, nvmem, data_len, data);
230 static int onie_tlv_probe(struct nvmem_layout *layout)
232 layout->add_cells = onie_tlv_parse_table;
234 return nvmem_layout_register(layout);
237 static void onie_tlv_remove(struct nvmem_layout *layout)
239 nvmem_layout_unregister(layout);
242 static const struct of_device_id onie_tlv_of_match_table[] = {
243 { .compatible = "onie,tlv-layout", },
246 MODULE_DEVICE_TABLE(of, onie_tlv_of_match_table);
248 static struct nvmem_layout_driver onie_tlv_layout = {
250 .owner = THIS_MODULE,
251 .name = "onie-tlv-layout",
252 .of_match_table = onie_tlv_of_match_table,
254 .probe = onie_tlv_probe,
255 .remove = onie_tlv_remove,
257 module_nvmem_layout_driver(onie_tlv_layout);
259 MODULE_LICENSE("GPL");
260 MODULE_AUTHOR("Miquel Raynal <miquel.raynal@bootlin.com>");
261 MODULE_DESCRIPTION("NVMEM layout driver for Onie TLV table parsing");