diff options
Diffstat (limited to 'src/drivers/spi/cbfs_spi.c')
-rw-r--r-- | src/drivers/spi/cbfs_spi.c | 80 |
1 files changed, 80 insertions, 0 deletions
diff --git a/src/drivers/spi/cbfs_spi.c b/src/drivers/spi/cbfs_spi.c new file mode 100644 index 0000000000..bbe9125dd5 --- /dev/null +++ b/src/drivers/spi/cbfs_spi.c @@ -0,0 +1,80 @@ +/* + * 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_DEVICE_SPI_FLASH_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; +} |