On Mon, Oct 22, 2018 at 08:42:32AM +0100, Alexander Graf wrote:
> 
> 
> On 22.10.18 08:22, AKASHI Takahiro wrote:
> > On Mon, Oct 22, 2018 at 01:40:05PM +0900, 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.aka...@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"
> >> +          "fi;\0"
> >>  #define SCAN_DEV_FOR_EFI "run scan_dev_for_efi;"
> >> +#define BOOT_EFI_BOOT_MANAGER "bootefi bootmgr;"
> >>  #else
> >>  #define BOOTENV_SHARED_EFI
> >>  #define SCAN_DEV_FOR_EFI
> >> +#define BOOT_EFI_BOOT_MANAGER
> >>  #endif
> >>  
> >>  #ifdef CONFIG_SATA
> >> @@ -409,6 +410,7 @@
> >>    BOOT_TARGET_DEVICES(BOOTENV_DEV)                                  \
> >>    \
> >>    "distro_bootcmd=" BOOTENV_SET_SCSI_NEED_INIT                      \
> >> +          BOOT_EFI_BOOT_MANAGER                                     \
> > 
> > The last-minute change may have introduced a problem.
> > By moving "bootmgr" from scan_dev_for_efi" to here,
> > grub fails to start a grub.cfg menu, saying
> >   "error: no such device: /.disk/info."
> > 
> > Do you have any ideas?
> 
> I would guess that bootmgr doesn't set the loaded image target correctly
> and before it just happened to work because there was a load command
> before the bootmgr command?

The root cause was that efi_init_obj_list(), particularly efi_disk_register(),
is executed only once.
In my case, efi bootmgr is called before "usb start" in scan_dev_for_efi,
and any USB devices will not be added to efi object list forever.
Therefore, later on, grub itself can start but cannot detect/access its own
boot device (USB mass storage) via efi interface.

I think we can fix this problem in several ways:
1. run all 'device-scanning' commands, like "usb start" and "scsi scan,"
   before calling bootmgr in distro_bootcmd,
2. modify efi_obj_init_list() to check and register newly-detected devices,
3. add a device to efi object list dynamically whenever a 'device-scanning'
   command detects one,
4. search and check for a device on-the-fly with each efi device path
   (or handle?) specified in efi interface

What do you think?

-Takahiro Akashi

> https://github.com/u-boot/u-boot/blob/master/cmd/fs.c#L26
> 
> 
> Alex
_______________________________________________
U-Boot mailing list
U-Boot@lists.denx.de
https://lists.denx.de/listinfo/u-boot

Reply via email to