diff options
Diffstat (limited to 'src/soc/samsung/exynos5250/alternate_cbfs.c')
-rw-r--r-- | src/soc/samsung/exynos5250/alternate_cbfs.c | 176 |
1 files changed, 176 insertions, 0 deletions
diff --git a/src/soc/samsung/exynos5250/alternate_cbfs.c b/src/soc/samsung/exynos5250/alternate_cbfs.c new file mode 100644 index 0000000000..10b33f0c2b --- /dev/null +++ b/src/soc/samsung/exynos5250/alternate_cbfs.c @@ -0,0 +1,176 @@ +/* + * 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. + * + * 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 + */ + + +#include <assert.h> +#include <cbfs.h> /* This driver serves as a CBFS media source. */ +#include <stdlib.h> +#include <string.h> +#include <console/console.h> +#include "alternate_cbfs.h" +#include "power.h" +#include "spi.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 alternate_cbfs_size[__BOOT_BLOCK__] 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 + * alternate_cbfs_buffer[!__BOOT_BLOCK__] 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(struct cbfs_media *media) +{ +#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 + * alternate_cbfs_buffer 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", alternate_cbfs_buffer); + 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(struct cbfs_media *media) +{ +#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 buffer 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 = alternate_cbfs_size / 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, alternate_cbfs_buffer)) { + 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", alternate_cbfs_buffer); + first_run = 0; +#endif + return 0; +} + +static int alternate_cbfs_close(struct cbfs_media *media) { return 0; } + +static size_t alternate_cbfs_read(struct cbfs_media *media, void *dest, + size_t offset, size_t count) +{ + ASSERT(offset + count < alternate_cbfs_size); + memcpy(dest, alternate_cbfs_buffer + offset, count); + return count; +} + +static void *alternate_cbfs_map(struct cbfs_media *media, size_t offset, + size_t count) +{ + ASSERT(offset + count < alternate_cbfs_size); + return alternate_cbfs_buffer + offset; +} + +static void *alternate_cbfs_unmap(struct cbfs_media *media, + const void *buffer) { return 0; } + +static int initialize_exynos_sdmmc_cbfs_media(struct cbfs_media *media) +{ + printk(BIOS_DEBUG, "Using Exynos alternate boot mode SDMMC\n"); + + media->open = sdmmc_cbfs_open; + media->close = alternate_cbfs_close; + media->read = alternate_cbfs_read; + media->map = alternate_cbfs_map; + media->unmap = alternate_cbfs_unmap; + + return 0; +} + +static int initialize_exynos_usb_cbfs_media(struct cbfs_media *media) +{ + printk(BIOS_DEBUG, "Using Exynos alternate boot mode USB A-A\n"); + + media->open = usb_cbfs_open; + media->close = alternate_cbfs_close; + media->read = alternate_cbfs_read; + media->map = alternate_cbfs_map; + media->unmap = alternate_cbfs_unmap; + + return 0; +} + +int init_default_cbfs_media(struct cbfs_media *media) +{ + if (*iram_secondary_base == SECONDARY_BASE_BOOT_USB) + return initialize_exynos_usb_cbfs_media(media); + + switch (exynos_power->om_stat & OM_STAT_MASK) { + case OM_STAT_SDMMC: + return initialize_exynos_sdmmc_cbfs_media(media); + case OM_STAT_SPI: + return initialize_exynos_spi_cbfs_media(media, + (void*)CONFIG_CBFS_CACHE_ADDRESS, + CONFIG_CBFS_CACHE_SIZE); + default: + printk(BIOS_EMERG, "Exynos OM_STAT value 0x%x not supported!\n", + exynos_power->om_stat); + return 0; + } +} |