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/*
* This file is part of the coreboot project.
*
* Copyright 2013 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.
*/
#include <assert.h>
#include <boot_device.h>
#include <cbfs.h> /* This driver serves as a CBFS media source. */
#include <console/console.h>
#include <soc/alternate_cbfs.h>
#include <soc/power.h>
#include <soc/spi.h>
#include <stdlib.h>
#include <string.h>
#include <symbols.h>
/* This allows USB A-A firmware upload from a compatible host in four parts:
* The first two are the bare BL1 and the coreboot boot block, which are just
* written to their respective loading addresses. These transfers are initiated
* by the IROM / BL1, so this code has nothing to do with them.
*
* The third transfer is a valid CBFS image that contains only the romstage,
* and must be small enough to fit into the PRE_RAM CBFS cache in
* IRAM. It is loaded when this function gets called in the boot block, and
* the normal CBFS code extracts the romstage from it.
*
* The fourth transfer is also a CBFS image, but can be of arbitrary size and
* should contain all available stages/payloads/etc. It is loaded when this
* function is called a second time at the end of the romstage, and copied to
* the romstage/ramstage CBFS cache in DRAM. It will reside there for the
* rest of the firmware's lifetime and all subsequent stages (which will not
* have __PRE_RAM__ defined) can just directly reference it there.
*/
static int usb_cbfs_open(void)
{
#ifdef __PRE_RAM__
static int first_run = 1;
int (*irom_load_usb)(void) = *irom_load_image_from_usb_ptr;
if (!first_run)
return 0;
if (!irom_load_usb()) {
printk(BIOS_EMERG, "Unable to load CBFS image via USB!\n");
return -1;
}
/*
* We need to trust the host/irom to copy the image to our
* _cbfs_cache address... there is no way to control or even
* check the transfer size or target address from our side.
*/
printk(BIOS_DEBUG, "USB A-A transfer successful, CBFS image should now"
" be at %p\n", _cbfs_cache);
first_run = 0;
#endif
return 0;
}
/*
* SDMMC works very similar to USB A-A: we copy the CBFS image into memory
* and read it from there. While SDMMC would also allow direct block by block
* on-demand reading, we might run into problems if we call back into the IROM
* in very late boot stages (e.g. after initializing/changing MMC clocks)... so
* this seems like a safer approach. It also makes it easy to pass our image
* down to payloads.
*/
static int sdmmc_cbfs_open(void)
{
#ifdef __PRE_RAM__
/*
* In the bootblock, we just copy the small part that fits in the buffer
* and hope that it's enough (since the romstage is currently always the
* first component in the image, this should work out). In the romstage,
* we copy until our cache is full (currently 12M) to avoid the pain of
* figuring out the true image size from in here. Since this is mainly a
* developer/debug boot mode, those shortcomings should be bearable.
*/
const u32 count = REGION_SIZE(cbfs_cache) / 512;
static int first_run = 1;
int (*irom_load_sdmmc)(u32 start, u32 count, void *dst) =
*irom_sdmmc_read_blocks_ptr;
if (!first_run)
return 0;
if (!irom_load_sdmmc(1, count, _cbfs_cache)) {
printk(BIOS_EMERG, "Unable to load CBFS image from SDMMC!\n");
return -1;
}
printk(BIOS_DEBUG, "SDMMC read successful, CBFS image should now be"
" at %p\n", _cbfs_cache);
first_run = 0;
#endif
return 0;
}
static struct mem_region_device alternate_rdev =
MEM_REGION_DEV_RO_INIT(NULL, 0);
const struct region_device *boot_device_ro(void)
{
if (*iram_secondary_base == SECONDARY_BASE_BOOT_USB)
return &alternate_rdev.rdev;
switch (exynos_power->om_stat & OM_STAT_MASK) {
case OM_STAT_SDMMC:
return &alternate_rdev.rdev;
case OM_STAT_SPI:
return exynos_spi_boot_device();
default:
printk(BIOS_EMERG, "Exynos OM_STAT value 0x%x not supported!\n",
exynos_power->om_stat);
return NULL;
}
}
void boot_device_init(void)
{
mem_region_device_ro_init(&alternate_rdev, _cbfs_cache,
REGION_SIZE(cbfs_cache));
if (*iram_secondary_base == SECONDARY_BASE_BOOT_USB) {
printk(BIOS_DEBUG, "Using Exynos alternate boot mode USB A-A\n");
usb_cbfs_open();
return;
}
switch (exynos_power->om_stat & OM_STAT_MASK) {
case OM_STAT_SDMMC:
printk(BIOS_DEBUG, "Using Exynos alternate boot mode SDMMC\n");
sdmmc_cbfs_open();
break;
case OM_STAT_SPI:
exynos_init_spi_boot_device();
break;
default:
printk(BIOS_EMERG, "Exynos OM_STAT value 0x%x not supported!\n",
exynos_power->om_stat);
}
}
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