coreboot-kgpe-d16/src/lib/cbfs_spi.c

96 lines
2.5 KiB
C

/*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
/*
* 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 <cbfs.h>
#include <spi_flash.h>
/* SPI flash as CBFS media. */
struct cbfs_spi_context {
struct spi_flash *spi_flash_info;
struct cbfs_simple_buffer buffer;
};
static struct cbfs_spi_context spi_context;
static int cbfs_media_open(struct cbfs_media *media)
{
return 0;
}
static int cbfs_media_close(struct cbfs_media *media)
{
return 0;
}
static size_t cbfs_media_read(struct cbfs_media *media,
void *dest, size_t offset,
size_t count)
{
struct cbfs_spi_context *context = media->context;
return context->spi_flash_info->read
(context->spi_flash_info, offset, count, dest) ? 0 : count;
}
static void *cbfs_media_map(struct cbfs_media *media,
size_t offset, size_t count)
{
struct cbfs_spi_context *context = media->context;
return cbfs_simple_buffer_map(&context->buffer, media, offset, count);
}
static void *cbfs_media_unmap(struct cbfs_media *media,
const void *address)
{
struct cbfs_spi_context *context = media->context;
return cbfs_simple_buffer_unmap(&context->buffer, address);
}
int init_default_cbfs_media(struct cbfs_media *media)
{
if (spi_context.buffer.buffer)
return 0; /* It has been already initialized. */
spi_context.spi_flash_info = spi_flash_probe
(CONFIG_BOOT_MEDIA_SPI_BUS, 0);
if (!spi_context.spi_flash_info)
return -1;
spi_context.buffer.buffer = (void *)CONFIG_CBFS_CACHE_ADDRESS;
spi_context.buffer.size = CONFIG_CBFS_CACHE_SIZE;
media->context = &spi_context;
media->open = cbfs_media_open;
media->close = cbfs_media_close;
media->read = cbfs_media_read;
media->map = cbfs_media_map;
media->unmap = cbfs_media_unmap;
return 0;
}