From efeccfe7f3b3d45f9a94f4eb62f4548b1a2fbfb5 Mon Sep 17 00:00:00 2001 From: Sam Protsenko Date: Thu, 18 May 2017 15:04:59 +0300 Subject: [PATCH] fastboot: Add support for flashing zImage This patch adds support for flashing zImage to the Android boot partition on eMMC. Usage: $ fastboot flash zImage It's based on [1]. [1] http://omapzoom.org/?p=repo/u-boot.git;a=commit;h=3393b908c1e848bba3706612cbe50aa8970720b3 Signed-off-by: Sam Protsenko --- common/fb_mmc.c | 168 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 168 insertions(+) diff --git a/common/fb_mmc.c b/common/fb_mmc.c index 866982e41c..2113b6c372 100644 --- a/common/fb_mmc.c +++ b/common/fb_mmc.c @@ -13,6 +13,8 @@ #include #include #include +#include +#include /* * FIXME: Ensure we always set these names via Kconfig once xxx_PARTITION is @@ -27,6 +29,8 @@ #define CONFIG_FASTBOOT_MBR_NAME "mbr" #endif +#define BOOT_PARTITION_NAME "boot" + struct fb_mmc_sparse { struct blk_desc *dev_desc; }; @@ -99,6 +103,163 @@ static void write_raw_image(struct blk_desc *dev_desc, disk_partition_t *info, fastboot_okay(""); } +#ifdef CONFIG_ANDROID_BOOT_IMAGE +/** + * Read Android boot image header from boot partition. + * + * @param[in] dev_desc MMC device descriptor + * @param[in] info Boot partition info + * @param[out] hdr Where to store read boot image header + * + * @return Boot image header sectors count or 0 on error + */ +static lbaint_t fb_mmc_get_boot_header(struct blk_desc *dev_desc, + disk_partition_t *info, + struct andr_img_hdr *hdr) +{ + ulong sector_size; /* boot partition sector size */ + lbaint_t hdr_sectors; /* boot image header sectors count */ + int res; + + /* Calculate boot image sectors count */ + sector_size = info->blksz; + hdr_sectors = DIV_ROUND_UP(sizeof(struct andr_img_hdr), sector_size); + if (hdr_sectors == 0) { + error("invalid number of boot sectors: 0"); + fastboot_fail("invalid number of boot sectors: 0"); + return 0; + } + + /* Read the boot image header */ + res = blk_dread(dev_desc, info->start, hdr_sectors, (void *)hdr); + if (res == 0) { + error("cannot read header from boot partition"); + fastboot_fail("cannot read header from boot partition"); + return 0; + } + + /* Check boot header magic string */ + res = android_image_check_header(hdr); + if (res != 0) { + error("bad boot image magic"); + fastboot_fail("boot partition not initialized"); + return 0; + } + + return hdr_sectors; +} + +/** + * Write downloaded zImage to boot partition and repack it properly. + * + * @param dev_desc MMC device descriptor + * @param download_buffer Address to fastboot buffer with zImage in it + * @param download_bytes Size of fastboot buffer, in bytes + * + * @return 0 on success or -1 on error + */ +static int fb_mmc_update_zimage(struct blk_desc *dev_desc, + void *download_buffer, + unsigned int download_bytes) +{ + u32 hdr_addr; /* boot image header address */ + struct andr_img_hdr *hdr; /* boot image header */ + lbaint_t hdr_sectors; /* boot image header sectors */ + u8 *ramdisk_buffer; + u32 ramdisk_sector_start; + u32 ramdisk_sectors; + u32 kernel_sector_start; + u32 kernel_sectors; + u32 sectors_per_page; + disk_partition_t info; + int res; + + puts("Flashing zImage\n"); + + /* Get boot partition info */ + res = part_get_info_by_name(dev_desc, BOOT_PARTITION_NAME, &info); + if (res < 0) { + error("cannot find boot partition"); + fastboot_fail("cannot find boot partition"); + return -1; + } + + /* Put boot image header in fastboot buffer after downloaded zImage */ + hdr_addr = (u32)download_buffer + ALIGN(download_bytes, PAGE_SIZE); + hdr = (struct andr_img_hdr *)hdr_addr; + + /* Read boot image header */ + hdr_sectors = fb_mmc_get_boot_header(dev_desc, &info, hdr); + if (hdr_sectors == 0) { + error("unable to read boot image header"); + fastboot_fail("unable to read boot image header"); + return -1; + } + + /* Check if boot image has second stage in it (we don't support it) */ + if (hdr->second_size > 0) { + error("moving second stage is not supported yet"); + fastboot_fail("moving second stage is not supported yet"); + return -1; + } + + /* Extract ramdisk location */ + sectors_per_page = hdr->page_size / info.blksz; + ramdisk_sector_start = info.start + sectors_per_page; + ramdisk_sector_start += DIV_ROUND_UP(hdr->kernel_size, hdr->page_size) * + sectors_per_page; + ramdisk_sectors = DIV_ROUND_UP(hdr->ramdisk_size, hdr->page_size) * + sectors_per_page; + + /* Read ramdisk and put it in fastboot buffer after boot image header */ + ramdisk_buffer = (u8 *)hdr + (hdr_sectors * info.blksz); + res = blk_dread(dev_desc, ramdisk_sector_start, ramdisk_sectors, + ramdisk_buffer); + if (res == 0) { + error("cannot read ramdisk from boot partition"); + fastboot_fail("cannot read ramdisk from boot partition"); + return -1; + } + + /* Write new kernel size to boot image header */ + hdr->kernel_size = download_bytes; + res = blk_dwrite(dev_desc, info.start, hdr_sectors, (void *)hdr); + if (res == 0) { + error("cannot writeback boot image header"); + fastboot_fail("cannot write back boot image header"); + return -1; + } + + /* Write the new downloaded kernel */ + kernel_sector_start = info.start + sectors_per_page; + kernel_sectors = DIV_ROUND_UP(hdr->kernel_size, hdr->page_size) * + sectors_per_page; + res = blk_dwrite(dev_desc, kernel_sector_start, kernel_sectors, + download_buffer); + if (res == 0) { + error("cannot write new kernel"); + fastboot_fail("cannot write new kernel"); + return -1; + } + + /* Write the saved ramdisk back */ + ramdisk_sector_start = info.start + sectors_per_page; + ramdisk_sector_start += DIV_ROUND_UP(hdr->kernel_size, hdr->page_size) * + sectors_per_page; + res = blk_dwrite(dev_desc, ramdisk_sector_start, ramdisk_sectors, + ramdisk_buffer); + if (res == 0) { + error("cannot write back original ramdisk"); + fastboot_fail("cannot write back original ramdisk"); + return -1; + } + + puts("........ zImage was updated in boot partition\n"); + fastboot_okay(""); + return 0; +} +#endif + void fb_mmc_flash_write(const char *cmd, void *download_buffer, unsigned int download_bytes) { @@ -153,6 +314,13 @@ void fb_mmc_flash_write(const char *cmd, void *download_buffer, } #endif +#ifdef CONFIG_ANDROID_BOOT_IMAGE + if (strncasecmp(cmd, "zimage", 6) == 0) { + fb_mmc_update_zimage(dev_desc, download_buffer, download_bytes); + return; + } +#endif + if (part_get_info_by_name_or_alias(dev_desc, cmd, &info) < 0) { error("cannot find partition: '%s'\n", cmd); fastboot_fail("cannot find partition"); -- 2.39.5