| /* |
| * This file is part of the coreboot project. |
| * |
| * Copyright 2014 Google Inc. |
| * |
| * 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. |
| */ |
| |
| /* |
| * This file provides a common CBFS wrapper for SPI storage. SPI driver |
| * context is expanded with the buffer descriptor used to store data read from |
| * SPI. |
| */ |
| |
| #include <boot_device.h> |
| #include <spi_flash.h> |
| #include <symbols.h> |
| #include <cbmem.h> |
| |
| static struct spi_flash *spi_flash_info; |
| |
| static ssize_t spi_readat(const struct region_device *rd, void *b, |
| size_t offset, size_t size) |
| { |
| if (spi_flash_info->read(spi_flash_info, offset, size, b)) |
| return -1; |
| return size; |
| } |
| |
| static const struct region_device_ops spi_ops = { |
| .mmap = mmap_helper_rdev_mmap, |
| .munmap = mmap_helper_rdev_munmap, |
| .readat = spi_readat, |
| }; |
| |
| static struct mmap_helper_region_device mdev = |
| MMAP_HELPER_REGION_INIT(&spi_ops, 0, CONFIG_ROM_SIZE); |
| |
| static void switch_to_postram_cache(int unused) |
| { |
| /* |
| * Call boot_device_init() to ensure spi_flash is initialized before |
| * backing mdev with postram cache. This prevents the mdev backing from |
| * being overwritten if spi_flash was not accessed before dram was up. |
| */ |
| boot_device_init(); |
| if (_preram_cbfs_cache != _postram_cbfs_cache) |
| mmap_helper_device_init(&mdev, _postram_cbfs_cache, |
| _postram_cbfs_cache_size); |
| } |
| ROMSTAGE_CBMEM_INIT_HOOK(switch_to_postram_cache); |
| |
| void boot_device_init(void) |
| { |
| int bus = CONFIG_BOOT_MEDIA_SPI_BUS; |
| int cs = 0; |
| |
| if (spi_flash_info != NULL) |
| return; |
| |
| spi_flash_info = spi_flash_probe(bus, cs); |
| |
| mmap_helper_device_init(&mdev, _cbfs_cache, _cbfs_cache_size); |
| } |
| |
| /* Return the CBFS boot device. */ |
| const struct region_device *boot_device_ro(void) |
| { |
| if (spi_flash_info == NULL) |
| return NULL; |
| |
| return &mdev.rdev; |
| } |