diff options
Diffstat (limited to 'drivers/nvmem/layouts/onie-tlv.c')
| -rw-r--r-- | drivers/nvmem/layouts/onie-tlv.c | 244 |
1 files changed, 244 insertions, 0 deletions
diff --git a/drivers/nvmem/layouts/onie-tlv.c b/drivers/nvmem/layouts/onie-tlv.c new file mode 100644 index 0000000000..59fc87ccfc --- /dev/null +++ b/drivers/nvmem/layouts/onie-tlv.c @@ -0,0 +1,244 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * ONIE tlv NVMEM cells provider + * + * Copyright (C) 2022 Open Compute Group ONIE + * Author: Miquel Raynal <miquel.raynal@bootlin.com> + * Based on the nvmem driver written by: Vadym Kochan <vadym.kochan@plvision.eu> + * Inspired by the first layout written by: Rafał Miłecki <rafal@milecki.pl> + */ + +#include <linux/crc32.h> +#include <linux/etherdevice.h> +#include <linux/nvmem-consumer.h> +#include <linux/nvmem-provider.h> +#include <linux/of.h> + +#define ONIE_TLV_MAX_LEN 2048 +#define ONIE_TLV_CRC_FIELD_SZ 6 +#define ONIE_TLV_CRC_SZ 4 +#define ONIE_TLV_HDR_ID "TlvInfo" + +struct onie_tlv_hdr { + u8 id[8]; + u8 version; + __be16 data_len; +} __packed; + +struct onie_tlv { + u8 type; + u8 len; +} __packed; + +static const char *onie_tlv_cell_name(u8 type) +{ + switch (type) { + case 0x21: + return "product-name"; + case 0x22: + return "part-number"; + case 0x23: + return "serial-number"; + case 0x24: + return "mac-address"; + case 0x25: + return "manufacture-date"; + case 0x26: + return "device-version"; + case 0x27: + return "label-revision"; + case 0x28: + return "platform-name"; + case 0x29: + return "onie-version"; + case 0x2A: + return "num-macs"; + case 0x2B: + return "manufacturer"; + case 0x2C: + return "country-code"; + case 0x2D: + return "vendor"; + case 0x2E: + return "diag-version"; + case 0x2F: + return "service-tag"; + case 0xFD: + return "vendor-extension"; + case 0xFE: + return "crc32"; + default: + break; + } + + return NULL; +} + +static int onie_tlv_mac_read_cb(void *priv, const char *id, int index, + unsigned int offset, void *buf, + size_t bytes) +{ + eth_addr_add(buf, index); + + return 0; +} + +static nvmem_cell_post_process_t onie_tlv_read_cb(u8 type, u8 *buf) +{ + switch (type) { + case 0x24: + return &onie_tlv_mac_read_cb; + default: + break; + } + + return NULL; +} + +static int onie_tlv_add_cells(struct device *dev, struct nvmem_device *nvmem, + size_t data_len, u8 *data) +{ + struct nvmem_cell_info cell = {}; + struct device_node *layout; + struct onie_tlv tlv; + unsigned int hdr_len = sizeof(struct onie_tlv_hdr); + unsigned int offset = 0; + int ret; + + layout = of_nvmem_layout_get_container(nvmem); + if (!layout) + return -ENOENT; + + while (offset < data_len) { + memcpy(&tlv, data + offset, sizeof(tlv)); + if (offset + tlv.len >= data_len) { + dev_err(dev, "Out of bounds field (0x%x bytes at 0x%x)\n", + tlv.len, hdr_len + offset); + break; + } + + cell.name = onie_tlv_cell_name(tlv.type); + if (!cell.name) + continue; + + cell.offset = hdr_len + offset + sizeof(tlv.type) + sizeof(tlv.len); + cell.bytes = tlv.len; + cell.np = of_get_child_by_name(layout, cell.name); + cell.read_post_process = onie_tlv_read_cb(tlv.type, data + offset + sizeof(tlv)); + + ret = nvmem_add_one_cell(nvmem, &cell); + if (ret) { + of_node_put(layout); + return ret; + } + + offset += sizeof(tlv) + tlv.len; + } + + of_node_put(layout); + + return 0; +} + +static bool onie_tlv_hdr_is_valid(struct device *dev, struct onie_tlv_hdr *hdr) +{ + if (memcmp(hdr->id, ONIE_TLV_HDR_ID, sizeof(hdr->id))) { + dev_err(dev, "Invalid header\n"); + return false; + } + + if (hdr->version != 0x1) { + dev_err(dev, "Invalid version number\n"); + return false; + } + + return true; +} + +static bool onie_tlv_crc_is_valid(struct device *dev, size_t table_len, u8 *table) +{ + struct onie_tlv crc_hdr; + u32 read_crc, calc_crc; + __be32 crc_be; + + memcpy(&crc_hdr, table + table_len - ONIE_TLV_CRC_FIELD_SZ, sizeof(crc_hdr)); + if (crc_hdr.type != 0xfe || crc_hdr.len != ONIE_TLV_CRC_SZ) { + dev_err(dev, "Invalid CRC field\n"); + return false; + } + + /* The table contains a JAMCRC, which is XOR'ed compared to the original + * CRC32 implementation as known in the Ethernet world. + */ + memcpy(&crc_be, table + table_len - ONIE_TLV_CRC_SZ, ONIE_TLV_CRC_SZ); + read_crc = be32_to_cpu(crc_be); + calc_crc = crc32(~0, table, table_len - ONIE_TLV_CRC_SZ) ^ 0xFFFFFFFF; + if (read_crc != calc_crc) { + dev_err(dev, "Invalid CRC read: 0x%08x, expected: 0x%08x\n", + read_crc, calc_crc); + return false; + } + + return true; +} + +static int onie_tlv_parse_table(struct device *dev, struct nvmem_device *nvmem, + struct nvmem_layout *layout) +{ + struct onie_tlv_hdr hdr; + size_t table_len, data_len, hdr_len; + u8 *table, *data; + int ret; + + ret = nvmem_device_read(nvmem, 0, sizeof(hdr), &hdr); + if (ret < 0) + return ret; + + if (!onie_tlv_hdr_is_valid(dev, &hdr)) { + dev_err(dev, "Invalid ONIE TLV header\n"); + return -EINVAL; + } + + hdr_len = sizeof(hdr.id) + sizeof(hdr.version) + sizeof(hdr.data_len); + data_len = be16_to_cpu(hdr.data_len); + table_len = hdr_len + data_len; + if (table_len > ONIE_TLV_MAX_LEN) { + dev_err(dev, "Invalid ONIE TLV data length\n"); + return -EINVAL; + } + + table = devm_kmalloc(dev, table_len, GFP_KERNEL); + if (!table) + return -ENOMEM; + + ret = nvmem_device_read(nvmem, 0, table_len, table); + if (ret != table_len) + return ret; + + if (!onie_tlv_crc_is_valid(dev, table_len, table)) + return -EINVAL; + + data = table + hdr_len; + ret = onie_tlv_add_cells(dev, nvmem, data_len, data); + if (ret) + return ret; + + return 0; +} + +static const struct of_device_id onie_tlv_of_match_table[] = { + { .compatible = "onie,tlv-layout", }, + {}, +}; +MODULE_DEVICE_TABLE(of, onie_tlv_of_match_table); + +static struct nvmem_layout onie_tlv_layout = { + .name = "ONIE tlv layout", + .of_match_table = onie_tlv_of_match_table, + .add_cells = onie_tlv_parse_table, +}; +module_nvmem_layout_driver(onie_tlv_layout); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Miquel Raynal <miquel.raynal@bootlin.com>"); +MODULE_DESCRIPTION("NVMEM layout driver for Onie TLV table parsing"); |