| /* |
| * This file is part of the coreboot project. |
| * |
| * Copyright (C) 2013 Google Inc. |
| * Copyright (C) 2014 Sage Electronic Engineering, LLC. |
| * |
| * 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. |
| */ |
| |
| #include <stdint.h> |
| #include <stddef.h> |
| #include <console/console.h> |
| #include <string.h> |
| #include <spi-generic.h> |
| #include <spi_flash.h> |
| #include <baytrail/nvm.h> |
| |
| /* This module assumes the flash is memory mapped just below 4GiB in the |
| * address space for reading. Also this module assumes an area it erased |
| * when all bytes read as all 0xff's. */ |
| |
| static struct spi_flash *flash; |
| |
| static int nvm_init(void) |
| { |
| if (flash != NULL) |
| return 0; |
| |
| spi_init(); |
| flash = spi_flash_probe(0, 0); |
| if (!flash) { |
| printk(BIOS_DEBUG, "Could not find SPI device\n"); |
| return -1; |
| } |
| |
| return 0; |
| } |
| |
| /* Convert memory mapped pointer to flash offset. */ |
| static inline uint32_t to_flash_offset(void *p) |
| { |
| return CONFIG_ROM_SIZE + (uintptr_t)p; |
| } |
| |
| int nvm_is_erased(const void *start, size_t size) |
| { |
| const uint8_t *cur = start; |
| const uint8_t erased_value = 0xff; |
| |
| while (size > 0) { |
| if (*cur != erased_value) |
| return 0; |
| cur++; |
| size--; |
| } |
| return 1; |
| } |
| |
| int nvm_erase(void *start, size_t size) |
| { |
| if (nvm_init() < 0) |
| return -1; |
| flash->erase(flash, to_flash_offset(start), size); |
| return 0; |
| } |
| |
| /* Write data to NVM. Returns 0 on success < 0 on error. */ |
| int nvm_write(void *start, const void *data, size_t size) |
| { |
| if (nvm_init() < 0) |
| return -1; |
| flash->write(flash, to_flash_offset(start), size, data); |
| return 0; |
| } |