From acfa9bdfa7391f1872aa67bc6e4d3cd38e11d6c9 Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Sun, 24 Apr 2022 23:31:17 -0600 Subject: [PATCH] bootstd: Add an implementation of EFI boot Add a bootmeth driver which handles EFI boot, using EFI_LOADER. In effect, this provides the same functionality as the 'bootefi' command and shares the same code. But the interface into it is via a bootmeth, so it does not require any special scripts, etc. For now this requires the 'bootefi' command be enabled. Future work may tidy this up so that it can be used without CONFIG_CMDLINE being enabled. There was much discussion about whether this is needed, but it seems that it is, at least for now. Signed-off-by: Simon Glass --- boot/Kconfig | 21 +++++ boot/Makefile | 1 + boot/bootmeth_efi.c | 188 ++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 210 insertions(+) create mode 100644 boot/bootmeth_efi.c diff --git a/boot/Kconfig b/boot/Kconfig index 9e02a7549a..0bfea2791d 100644 --- a/boot/Kconfig +++ b/boot/Kconfig @@ -349,6 +349,27 @@ config BOOTMETH_DISTRO_PXE This provides a way to try out standard boot on an existing boot flow. +config BOOTMETH_EFILOADER + bool "Bootdev support for EFI boot" + depends on CMD_BOOTEFI + default y + help + Enables support for EFI boot using bootdevs. This makes the + bootdevs look for a 'boot.efi' on each filesystem + they scan. The resulting file is booted after enabling U-Boot's + EFI loader support. + + The depends on the architecture of the board: + + aa64 - aarch64 (ARM 64-bit) + arm - ARM 32-bit + ia32 - x86 32-bit + x64 - x86 64-bit + riscv32 - RISC-V 32-bit + riscv64 - RISC-V 64-bit + + This provides a way to try out standard boot on an existing boot flow. + endif config LEGACY_IMAGE_FORMAT diff --git a/boot/Makefile b/boot/Makefile index 9c9613d22a..4f9267687f 100644 --- a/boot/Makefile +++ b/boot/Makefile @@ -26,6 +26,7 @@ obj-$(CONFIG_$(SPL_TPL_)BOOTSTD) += bootstd-uclass.o obj-$(CONFIG_$(SPL_TPL_)BOOTMETH_DISTRO) += bootmeth_distro.o obj-$(CONFIG_$(SPL_TPL_)BOOTMETH_DISTRO_PXE) += bootmeth_pxe.o +obj-$(CONFIG_$(SPL_TPL_)BOOTMETH_EFILOADER) += bootmeth_efi.o obj-$(CONFIG_$(SPL_TPL_)OF_LIBFDT) += image-fdt.o obj-$(CONFIG_$(SPL_TPL_)FIT_SIGNATURE) += fdt_region.o diff --git a/boot/bootmeth_efi.c b/boot/bootmeth_efi.c new file mode 100644 index 0000000000..d5438eb67b --- /dev/null +++ b/boot/bootmeth_efi.c @@ -0,0 +1,188 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Bootmethod for distro boot via EFI + * + * Copyright 2021 Google LLC + * Written by Simon Glass + */ + +#define LOG_CATEGORY UCLASS_BOOTSTD + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define EFI_DIRNAME "efi/boot/" + +/** + * get_efi_leafname() - Get the leaf name for the EFI file we expect + * + * @str: Place to put leaf name for this architecture, e.g. "bootaa64.efi". + * Must have at least 16 bytes of space + * @max_len: Length of @str, must be >=16 + */ +static int get_efi_leafname(char *str, int max_len) +{ + const char *base; + + if (max_len < 16) + return log_msg_ret("spc", -ENOSPC); + if (IS_ENABLED(CONFIG_ARM64)) + base = "bootaa64"; + else if (IS_ENABLED(CONFIG_ARM)) + base = "bootarm"; + else if (IS_ENABLED(CONFIG_X86_RUN_32BIT)) + base = "bootia32"; + else if (IS_ENABLED(CONFIG_X86_RUN_64BIT)) + base = "bootx64"; + else if (IS_ENABLED(CONFIG_ARCH_RV32I)) + base = "bootriscv32"; + else if (IS_ENABLED(CONFIG_ARCH_RV64I)) + base = "bootriscv64"; + else if (IS_ENABLED(CONFIG_SANDBOX)) + base = "bootsbox"; + else + return -EINVAL; + + strcpy(str, base); + strcat(str, ".efi"); + + return 0; +} + +static int efiload_read_file(struct blk_desc *desc, struct bootflow *bflow) +{ + const struct udevice *media_dev; + int size = bflow->size; + const char *dev_name; + char devnum_str[9]; + char dirname[200]; + char *last_slash; + int ret; + + ret = bootmeth_alloc_file(bflow, 0x2000000, 0x10000); + if (ret) + return log_msg_ret("read", ret); + + /* + * This is a horrible hack to tell EFI about this boot device. Once we + * unify EFI with the rest of U-Boot we can clean this up. The same hack + * exists in multiple places, e.g. in the fs, tftp and load commands. + * + * Once we can clean up the EFI code to make proper use of driver model, + * this can go away. + */ + media_dev = dev_get_parent(bflow->dev); + snprintf(devnum_str, sizeof(devnum_str), "%x", dev_seq(media_dev)); + + strlcpy(dirname, bflow->fname, sizeof(dirname)); + last_slash = strrchr(dirname, '/'); + if (last_slash) + *last_slash = '\0'; + + log_debug("setting bootdev %s, %s, %s, %p, %x\n", + dev_get_uclass_name(media_dev), devnum_str, bflow->fname, + bflow->buf, size); + dev_name = device_get_uclass_id(media_dev) == UCLASS_MASS_STORAGE ? + "usb" : dev_get_uclass_name(media_dev); + efi_set_bootdev(dev_name, devnum_str, bflow->fname, bflow->buf, size); + + return 0; +} + +static int distro_efi_check(struct udevice *dev, struct bootflow_iter *iter) +{ + int ret; + + /* This only works on block devices */ + ret = bootflow_iter_uses_blk_dev(iter); + if (ret) + return log_msg_ret("blk", ret); + + return 0; +} + +static int distro_efi_read_bootflow(struct udevice *dev, struct bootflow *bflow) +{ + struct blk_desc *desc = NULL; + char fname[sizeof(EFI_DIRNAME) + 16]; + int ret; + + /* We require a partition table */ + if (!bflow->part) + return -ENOENT; + + strcpy(fname, EFI_DIRNAME); + ret = get_efi_leafname(fname + strlen(fname), + sizeof(fname) - strlen(fname)); + if (ret) + return log_msg_ret("leaf", ret); + + if (bflow->blk) + desc = dev_get_uclass_plat(bflow->blk); + ret = bootmeth_try_file(bflow, desc, NULL, fname); + if (ret) + return log_msg_ret("try", ret); + + ret = efiload_read_file(desc, bflow); + if (ret) + return log_msg_ret("read", -EINVAL); + + return 0; +} + +int distro_efi_boot(struct udevice *dev, struct bootflow *bflow) +{ + char cmd[50]; + + /* + * At some point we can add a real interface to bootefi so we can call + * this directly. For now, go through the CLI like distro boot. + */ + snprintf(cmd, sizeof(cmd), "bootefi %lx %lx", + (ulong)map_to_sysmem(bflow->buf), + (ulong)map_to_sysmem(gd->fdt_blob)); + if (run_command(cmd, 0)) + return log_msg_ret("run", -EINVAL); + + return 0; +} + +static int distro_bootmeth_efi_bind(struct udevice *dev) +{ + struct bootmeth_uc_plat *plat = dev_get_uclass_plat(dev); + + plat->desc = IS_ENABLED(CONFIG_BOOTSTD_FULL) ? + "EFI boot from an .efi file" : "EFI"; + + return 0; +} + +static struct bootmeth_ops distro_efi_bootmeth_ops = { + .check = distro_efi_check, + .read_bootflow = distro_efi_read_bootflow, + .read_file = bootmeth_common_read_file, + .boot = distro_efi_boot, +}; + +static const struct udevice_id distro_efi_bootmeth_ids[] = { + { .compatible = "u-boot,distro-efi" }, + { } +}; + +U_BOOT_DRIVER(bootmeth_efi) = { + .name = "bootmeth_efi", + .id = UCLASS_BOOTMETH, + .of_match = distro_efi_bootmeth_ids, + .ops = &distro_efi_bootmeth_ops, + .bind = distro_bootmeth_efi_bind, +};