[U-Boot] [PATCH v5 24/30] efi_loader: Add distro boot script for removable media

Alexander Graf
2016-03-09T23:05:12Z

On 04.03.16 01:10, Alexander Graf wrote:
> UEFI defines a simple boot protocol for removable media. There we should look
> at the EFI (first GPT FAT) partition and search for /efi/boot/bootXXX.efi with
> XXX being different between different platforms (x86, x64, arm, aa64, ...).
>
> This patch implements a simple version of that protocol for the default distro
> boot script. With this we can automatically boot from valid UEFI enabled
> removable media.
>
> Because from all I could see U-Boot by default doesn't deliver device tree
> blobs with its firmware, we also need to load the dtb from somewhere. Traverse
> the same EFI partition for an fdt file that fits our current board so that
> an OS receives a valid device tree when booted automatically.
>
> Signed-off-by: Alexander Graf <agraf@suse.de>
> Reviewed-by: Simon Glass <sjg@chromium.org>
> ---
> include/config_distro_bootcmd.h | 47 ++++++++++++++++++++++++++++++++++++++++-
> 1 file changed, 46 insertions(+), 1 deletion(-)
>
> diff --git a/include/config_distro_bootcmd.h b/include/config_distro_bootcmd.h
> index 37c6b43..c19f1b0 100644
> --- a/include/config_distro_bootcmd.h
> +++ b/include/config_distro_bootcmd.h
> @@ -90,6 +90,48 @@
> BOOT_TARGET_DEVICES_references_UBIFS_without_CONFIG_CMD_UBIFS
> #endif
>
> +#ifdef CONFIG_EFI_LOADER
> +#if defined(CONFIG_ARM64)
> +#define BOOTEFI_NAME "bootaa64.efi"
> +#elif defined(CONFIG_ARM)
> +#define BOOTEFI_NAME "bootarm.efi"
> +#endif
> +#endif
> +
> +#ifdef BOOTEFI_NAME
> +#define BOOTENV_SHARED_EFI \
> + "boot_efi_binary=" \
> + "load ${devtype} ${devnum}:${distro_bootpart} " \
> + "${kernel_addr_r} efi/boot/"BOOTEFI_NAME"; " \
> + "bootefi ${kernel_addr_r}\0" \
> + \
> + "load_efi_dtb=" \
> + "load ${devtype} ${devnum}:${distro_bootpart} " \
> + "${fdt_addr_r} ${prefix}${fdt_name}; " \
> + "fdt addr ${fdt_addr_r}\0" \
> + \
> + "efi_dtb_prefixes=/ /dtb/ /dtb/current/\0" \
> + "scan_dev_for_efi=" \
> + "for prefix in ${efi_dtb_prefixes}; do " \
> + "if test -e ${devtype} " \
> + "${devnum}:${distro_bootpart} " \
> + "${prefix}${fdt_name}; then " \
> + "run load_efi_dtb; " \
> + "fi;" \
> + "done;" \
> + "if test -e ${devtype} ${devnum}:${distro_bootpart} " \
> + "efi/boot/"BOOTEFI_NAME"; then " \
> + "echo Found EFI removable media binary " \
> + "efi/boot/"BOOTEFI_NAME"; " \
> + "run boot_efi_binary; " \
> + "echo EFI LOAD FAILED: continuing...; " \
> + "fi; "

Whoever applies this, please also apply the patch below on top and
squash it in (or tell me to resend). Without the fix, we end up slurping
the boot_prefix variable into the scan_dev_for_efi variable.

Alex

diff --git a/include/config_distro_bootcmd.h
b/include/config_distro_bootcmd.h
index e7d7002..ad9045e 100644
--- a/include/config_distro_bootcmd.h
+++ b/include/config_distro_bootcmd.h
@@ -125,7 +125,7 @@
"efi/boot/"BOOTEFI_NAME"; " \
"run boot_efi_binary; " \
"echo EFI LOAD FAILED: continuing...; " \
- "fi; "
+ "fi; \0"
#define SCAN_DEV_FOR_EFI "run scan_dev_for_efi;"
#else
#define BOOTENV_SHARED_EFI