| /* SPDX-License-Identifier: GPL-2.0-only */ |
| |
| #include <assert.h> |
| #include <device/pci_ops.h> |
| #include <delay.h> |
| #include <console/console.h> |
| #include <crc_byte.h> |
| #include <device/smbus_host.h> |
| #include <soc/intel/common/block/smbus/smbuslib.h> |
| #include <types.h> |
| |
| #include "variants/baseboard/include/eeprom.h" |
| |
| #define I2C_ADDR_EEPROM 0x57 |
| |
| /* |
| * Check Signature in EEPROM (M24C32-FMN6TP) |
| * If signature is there we assume that that the content is valid |
| */ |
| int check_signature(const size_t offset, const uint64_t signature) |
| { |
| u8 blob[8] = {0}; |
| |
| if (!read_write_config(blob, offset, 0, ARRAY_SIZE(blob))) { |
| /* Check signature */ |
| if (*(uint64_t *)blob == signature) { |
| printk(BIOS_DEBUG, "CFG EEPROM: Signature valid.\n"); |
| return 1; |
| } |
| printk(BIOS_DEBUG, "CFG EEPROM: Signature invalid - skipping option write.\n"); |
| return 0; |
| } |
| return 0; |
| } |
| |
| /* |
| * Read board settings from the EEPROM and verify their checksum. |
| * If checksum is valid, we assume the settings are sane as well. |
| */ |
| static bool get_board_settings_from_eeprom(struct eeprom_board_settings *board_cfg) |
| { |
| const size_t board_settings_offset = offsetof(struct eeprom_layout, BoardSettings); |
| |
| if (read_write_config(board_cfg, board_settings_offset, 0, sizeof(*board_cfg))) { |
| printk(BIOS_ERR, "CFG EEPROM: Failed to read board settings\n"); |
| return false; |
| } |
| |
| const uint32_t crc = |
| CRC(&board_cfg->raw_settings, sizeof(board_cfg->raw_settings), crc32_byte); |
| |
| if (crc != board_cfg->signature) { |
| printk(BIOS_ERR, "CFG EEPROM: Board settings have invalid checksum\n"); |
| return false; |
| } |
| return true; |
| } |
| |
| struct eeprom_board_settings *get_board_settings(void) |
| { |
| static struct eeprom_board_settings board_cfg = {0}; |
| |
| /* Tri-state: -1: settings are invalid, 0: uninitialized, 1: settings are valid */ |
| static int checked_valid = 0; |
| |
| if (checked_valid == 0) { |
| const bool success = get_board_settings_from_eeprom(&board_cfg); |
| checked_valid = success ? 1 : -1; |
| } |
| return checked_valid > 0 ? &board_cfg : NULL; |
| } |
| |
| struct eeprom_bmc_settings *get_bmc_settings(void) |
| { |
| const size_t bmc_settings_offset = offsetof(struct eeprom_layout, BMCSettings); |
| static struct eeprom_bmc_settings bmc_cfg = {0}; |
| |
| /* 0: uninitialized, 1: settings are valid */ |
| static int valid = 0; |
| |
| if (valid == 0) { |
| if (read_write_config(&bmc_cfg, bmc_settings_offset, 0, sizeof(bmc_cfg))) { |
| printk(BIOS_ERR, "CFG EEPROM: Failed to read BMC settings\n"); |
| return NULL; |
| } |
| valid = 1; |
| } |
| return &bmc_cfg; |
| } |
| |
| uint8_t get_bmc_hsi(void) |
| { |
| uint8_t hsi = 0; |
| struct eeprom_bmc_settings *s = get_bmc_settings(); |
| if (s) |
| hsi = s->hsi; |
| printk(BIOS_DEBUG, "CFG EEPROM: HSI 0x%x\n", hsi); |
| |
| return hsi; |
| } |
| |
| /* Read data from offset and write it to offset in UPD */ |
| bool read_write_config(void *blob, size_t read_offset, size_t write_offset, size_t size) |
| { |
| int ret = 0; |
| |
| u32 smb_ctrl_reg = pci_read_config32(PCH_DEV_SMBUS, HOSTC); |
| pci_write_config32(PCH_DEV_SMBUS, HOSTC, smb_ctrl_reg | I2C_EN); |
| |
| printk(BIOS_SPEW, "%s\tOffset: %04zx\tSize: %02zx\n", __func__, |
| read_offset, size); |
| |
| /* We can always read two bytes at a time */ |
| for (size_t i = 0; i < size; i = i + 2) { |
| u8 tmp[2] = {0}; |
| |
| ret = do_smbus_process_call(SMBUS_IO_BASE, I2C_ADDR_EEPROM, 0, |
| swab16(read_offset + i), (uint16_t *)&tmp[0]); |
| if (ret < 0) |
| break; |
| |
| /* Write to UPD */ |
| uint8_t *writePointer = (uint8_t *)blob + write_offset + i; |
| if (size > 1 && (size % 2 == 0)) |
| memcpy(writePointer, tmp, 2); |
| else |
| *writePointer = tmp[0]; |
| } |
| |
| /* Restore I2C_EN bit */ |
| pci_write_config32(PCH_DEV_SMBUS, HOSTC, smb_ctrl_reg); |
| |
| return ret; |
| } |
| |
| void report_eeprom_error(const size_t off) |
| { |
| printk(BIOS_ERR, "MB: Failed to read from EEPROM at addr. 0x%zx\n", off); |
| } |
| |
| /* |
| * Write a single byte into the EEPROM at specified offset. |
| * Returns true on error, false on success. |
| */ |
| static bool write_byte_eeprom(const uint8_t data, const uint16_t write_offset) |
| { |
| int ret = 0; |
| |
| printk(BIOS_SPEW, "CFG EEPROM: Writing %x at %x\n", data, write_offset); |
| |
| const uint32_t smb_ctrl_reg = pci_read_config32(PCH_DEV_SMBUS, HOSTC); |
| pci_write_config32(PCH_DEV_SMBUS, HOSTC, smb_ctrl_reg | I2C_EN); |
| |
| /* |
| * The EEPROM expects two address bytes. |
| * Use the first byte of the block data as second address byte. |
| */ |
| uint8_t buffer[2] = { |
| write_offset & 0xff, |
| data, |
| }; |
| |
| for (size_t retry = 3; retry > 0; retry--) { |
| /* The EEPROM NACKs request when busy writing */ |
| ret = do_smbus_block_write(SMBUS_IO_BASE, I2C_ADDR_EEPROM, |
| (write_offset >> 8) & 0xff, |
| sizeof(buffer), buffer); |
| if (ret == sizeof(buffer)) |
| break; |
| /* Maximum of 5 milliseconds write duration */ |
| mdelay(5); |
| } |
| |
| /* Restore I2C_EN bit */ |
| pci_write_config32(PCH_DEV_SMBUS, HOSTC, smb_ctrl_reg); |
| |
| return ret != sizeof(buffer); |
| } |
| |
| /* |
| * Write board layout if it has changed into EEPROM. |
| * Return true on error, false on success. |
| */ |
| bool write_board_settings(const struct eeprom_board_layout *new_layout) |
| { |
| const size_t off = offsetof(struct eeprom_layout, BoardLayout); |
| struct eeprom_board_layout old_layout = {0}; |
| bool ret = false; |
| bool changed = false; |
| |
| /* Read old settings */ |
| if (read_write_config(&old_layout, off, 0, sizeof(old_layout))) { |
| printk(BIOS_ERR, "CFG EEPROM: Read operation failed\n"); |
| return true; |
| } |
| |
| assert(sizeof(old_layout) == sizeof(*new_layout)); |
| const uint8_t *const old = (const uint8_t *)&old_layout; |
| const uint8_t *const new = (const uint8_t *)new_layout; |
| |
| /* Compare with new settings and only write changed bytes */ |
| for (size_t i = 0; i < sizeof(old_layout); i++) { |
| if (old[i] != new[i]) { |
| changed = true; |
| if (write_byte_eeprom(new[i], off + i)) { |
| printk(BIOS_ERR, "CFG EEPROM: Write operation failed\n"); |
| ret = true; |
| break; |
| } |
| } |
| } |
| |
| printk(BIOS_DEBUG, "CFG EEPROM: Board Layout up%s\n", changed ? "dated" : " to date"); |
| |
| return ret; |
| } |