[U-Boot] [PATCH v3 1/1] efi_loader: rework fdt handling in distro boot script

Alexander Graf
2018-12-02T22:58:45Z

On 27.11.18 01:33, AKASHI Takahiro wrote:
> The current scenario for default UEFI booting, scan_dev_for_efi, has
> several issues:
> * load dtb dynamically even if its loacation (device) is not the same
> as BOOTEFI_NAME binary's, (reported by Alex)
> * invoke 'bootmgr' only if BOOTEFI_NAME binary does exit even though
> 'bootmgr' can and should work independently whether or not the binary
> exist,
> * in addition, invoke 'bootmgr' with dynamically-loaded dtb.
> This behavior is not expected. (reported by Alex)
> * always assume that a 'fdtfile' variable is defined,
> ("test -e ${devtype} ${devnum}:${distro_bootpart} "${prefix}${efi_fdtfile}"
> always returns true even if fdtfile is NULL with prefix=="/".)
> * redundantly check for 'fdt_addr_r' in boot_efi_binary
>
> In this patch, all the issues above are sorted out.
> Please note that the default behavior can be customized with:
> fdtfile: a dtb file name
> efi_dtb_prefixes: a list of paths for searching for a dtb file
>
> (this feature does work even without this patch.)
>
> Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
> ---
> include/config_distro_bootcmd.h | 38 +++++++++++++++++----------------
> 1 file changed, 20 insertions(+), 18 deletions(-)
>
> diff --git a/include/config_distro_bootcmd.h b/include/config_distro_bootcmd.h
> index 373fee78a999..256698309eb9 100644
> --- a/include/config_distro_bootcmd.h
> +++ b/include/config_distro_bootcmd.h
> @@ -115,7 +115,7 @@
> */
> #define BOOTENV_EFI_SET_FDTFILE_FALLBACK \
> "if test -z \"${fdtfile}\" -a -n \"${soc}\"; then " \
> - "setenv efi_fdtfile ${soc}-${board}${boardver}.dtb; " \
> + "efi_fdtfile=${soc}-${board}${boardver}.dtb; " \
> "fi; "
> #else
> #define BOOTENV_EFI_SET_FDTFILE_FALLBACK
> @@ -124,26 +124,20 @@
>
> #define BOOTENV_SHARED_EFI \
> "boot_efi_binary=" \
> - "if fdt addr ${fdt_addr_r}; then " \
> - "bootefi bootmgr ${fdt_addr_r};" \
> - "else " \
> - "bootefi bootmgr ${fdtcontroladdr};" \
> - "fi;" \
> "load ${devtype} ${devnum}:${distro_bootpart} " \
> "${kernel_addr_r} efi/boot/"BOOTEFI_NAME"; " \
> - "if fdt addr ${fdt_addr_r}; then " \
> - "bootefi ${kernel_addr_r} ${fdt_addr_r};" \
> - "else " \
> - "bootefi ${kernel_addr_r} ${fdtcontroladdr};" \
> - "fi\0" \
> + "bootefi ${kernel_addr_r} ${efi_fdt_addr};\0" \
> \
> "load_efi_dtb=" \
> - "load ${devtype} ${devnum}:${distro_bootpart} " \
> - "${fdt_addr_r} ${prefix}${efi_fdtfile}\0" \
> + "load ${devtype} ${devnum}:${distro_bootpart} " \
> + "${fdt_addr_r} ${prefix}${efi_fdtfile}; " \
> + "if fdt addr ${fdt_addr_r}; then " \
> + "efi_fdt_addr=${fdt_addr_r}; " \
> + "fi;\0" \
> \
> "efi_dtb_prefixes=/ /dtb/ /dtb/current/\0" \
> - "scan_dev_for_efi=" \
> - "setenv efi_fdtfile ${fdtfile}; " \
> + "set_efi_fdt_addr=" \
> + "efi_fdtfile=${fdtfile}; " \
> BOOTENV_EFI_SET_FDTFILE_FALLBACK \
> "for prefix in ${efi_dtb_prefixes}; do " \
> "if test -e ${devtype} " \
> @@ -151,19 +145,26 @@
> "${prefix}${efi_fdtfile}; then " \
> "run load_efi_dtb; " \
> "fi;" \
> - "done;" \
> + "done;\0" \
> + \
> + "scan_dev_for_efi=" \
> "if test -e ${devtype} ${devnum}:${distro_bootpart} " \
> "efi/boot/"BOOTEFI_NAME"; then " \
> "echo Found EFI removable media binary " \
> "efi/boot/"BOOTEFI_NAME"; " \
> + "efi_fdt_addr=${fdtcontroladdr}; " \
> + "if test -n \"${fdtfile}\"; then " \
> + "run set_efi_fdt_addr; " \
> + "fi; " \
> "run boot_efi_binary; " \
> "echo EFI LOAD FAILED: continuing...; " \
> - "fi; " \
> - "setenv efi_fdtfile\0"

This drops the bit that unsets the variable. So after the script, your
env will be different from before the script. Please run

U-Boot# printenv
U-Boot# boot (w/o any efi payload to boot)
U-Boot# printenv

Then diff the two environments. They should be identical.

Alex