[U-Boot] [PATCH 1/2] efi_loader: rework fdt handling in distro boot script

[Alexander Graf]

On 12.10.18 07:07, AKASHI Takahiro wrote:
> The current scenario for default UEFI booting, scan_dev_for_efi, has
> several issues:
> * invoke 'bootmgr' only if BOOTEFI_NAME binary does exit even though
>   'bootmgr' can and should work independently whether or not the binary
>   exist,
> * always assume that a 'fdtfile' variable is defined,
> * redundantly check for 'fdt_addr_r' in boot_efi_binary
> 
> In this patch, all the issues above are sorted out.
> 
> Signed-off-by: AKASHI Takahiro <takahiro.akashi at linaro.org>
> ---
>  include/config_distro_bootcmd.h | 43 ++++++++++++++++-----------------
>  1 file changed, 21 insertions(+), 22 deletions(-)
> 
> diff --git a/include/config_distro_bootcmd.h b/include/config_distro_bootcmd.h
> index 373fee78a999..76e12b7bf4ee 100644
> --- a/include/config_distro_bootcmd.h
> +++ b/include/config_distro_bootcmd.h
> @@ -124,42 +124,41 @@
>  
>  #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"         \
> +			"${fdt_addr_r} ${prefix}${efi_fdtfile};"	  \
> +		"if fdt addr ${fdt_addr_r}; then "			  \
> +			"setenv efi_fdt_addr ${fdt_addr_r}; "		  \
> +		"else; "						  \
> +			"setenv efi_fdt_addr ${fdtcontroladdr}; "	  \
> +		"fi;\0"							  \
>  	\
> -	"efi_dtb_prefixes=/ /dtb/ /dtb/current/\0"                        \
> -	"scan_dev_for_efi="                                               \
> +	"set_efi_fdt_addr="						  \
>  		"setenv efi_fdtfile ${fdtfile}; "                         \
>  		BOOTENV_EFI_SET_FDTFILE_FALLBACK                          \
> -		"for prefix in ${efi_dtb_prefixes}; do "                  \

I fail to see where the prefix logic went? Without that, our distro's
dtb loading will break.

> -			"if test -e ${devtype} "                          \
> -					"${devnum}:${distro_bootpart} "   \
> -					"${prefix}${efi_fdtfile}; then "  \
> -				"run load_efi_dtb; "                      \
> -			"fi;"                                             \
> -		"done;"                                                   \
> +		"if test x${efi_fdtfile} != x -a x{$fdt_addr_r} != x ; then " \
> +			"run load_efi_dtb; "				  \
> +		"else; "						  \
> +			"setenv efi_fdt_addr ${fdtcontroladdr}; "	  \
> +		"fi; "							  \

Just unconditionally set efi_fdt_addr=$fdtcontrolladdr before the check
(and invocation of load_efi_dtb). That way you don't need to check for
the failure case in load_efi_dtb again.


Alex

> +		"setenv efi_fdtfile\0"					  \
> +	\
> +	"efi_dtb_prefixes=/ /dtb/ /dtb/current/\0"                        \
> +	"scan_dev_for_efi="                                               \
> +		"run set_efi_fdt_addr; "				  \
> +		"bootefi bootmgr ${efi_fdt_addr};"			  \
>  		"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; "                                                    \
> -		"setenv efi_fdtfile\0"
> +		"fi; "							  \
> +		"setenv efi_fdt_addr\0"
>  #define SCAN_DEV_FOR_EFI "run scan_dev_for_efi;"
>  #else
>  #define BOOTENV_SHARED_EFI
>