[PATCH 09/10] efi: Support showing tables

[Simon Glass]

Hi Heinrich,

On Mon, 6 Mar 2023 at 01:39, Heinrich Schuchardt <xypron.glpk at gmx.de> wrote:
>
> On 2/26/23 02:33, Simon Glass wrote:
> > Add a command to display the tables provided by EFI.
> >
> > Signed-off-by: Simon Glass <sjg at chromium.org>
> > ---
> >
> >   cmd/efi.c             | 40 +++++++++++++++++++++++++++++++++++++++-
> >   doc/usage/cmd/efi.rst | 22 ++++++++++++++++++++++
> >   2 files changed, 61 insertions(+), 1 deletion(-)
> >
> > diff --git a/cmd/efi.c b/cmd/efi.c
> > index c0384e0db28..86988d9e9e2 100644
> > --- a/cmd/efi.c
> > +++ b/cmd/efi.c
> > @@ -7,10 +7,12 @@
> >   #include <common.h>
> >   #include <command.h>
> >   #include <efi.h>
> > +#include <efi_api.h>
> >   #include <errno.h>
> >   #include <log.h>
> >   #include <malloc.h>
> >   #include <sort.h>
> > +#include <uuid.h>
> >   #include <asm/global_data.h>
> >
> >   DECLARE_GLOBAL_DATA_PTR;
> > @@ -273,8 +275,43 @@ done:
> >       return ret ? CMD_RET_FAILURE : 0;
> >   }
> >
> > +static int do_efi_tables(struct cmd_tbl *cmdtp, int flag, int argc,
> > +                      char *const argv[])
>
>
> We already have function do_efi_show_tables() to print the list of EFI
> configuration tables. Please, avoid code duplication.

OK I created a separate file.

Of course the 'efidebug' command cannot be used in the app or payload,
since it did not create the systab.

>
> > +{
> > +     struct efi_system_table *systab;
> > +     int i;
> > +
> > +     if (IS_ENABLED(CONFIG_EFI_APP)) {
> > +             systab = efi_get_sys_table();
> > +             if (!systab) {
> > +                     printf("Cannot read system table\n");
> > +                     return CMD_RET_FAILURE;
> > +             }
> > +     } else {
> > +             int size;
> > +             int ret;
> > +
> > +             ret = efi_info_get(EFIET_SYS_TABLE, (void **)&systab, &size);
> > +             if (ret) {
> > +                     printf("Cannot find EFI system table (err=%d)\n", ret);
> > +                     return CMD_RET_FAILURE;
> > +             }
> > +     }
> > +     for (i = 0; i < systab->nr_tables; i++) {
> > +             struct efi_configuration_table *tab = &systab->tables[i];
> > +             char guid_str[37];
> > +
> > +             uuid_bin_to_str(tab->guid.b, guid_str, 1);
> > +             printf("%p  %s  %s\n", tab->table, guid_str,
> > +                    uuid_guid_get_str(tab->guid.b));
>
>
> do_efi_show_tables() does this with printf("%pUl (%pUs)\n",..).
>
> > +     }
> > +
> > +     return 0;
> > +}
> > +
> >   static struct cmd_tbl efi_commands[] = {
> >       U_BOOT_CMD_MKENT(mem, 1, 1, do_efi_mem, "", ""),
> > +     U_BOOT_CMD_MKENT(tables, 1, 1, do_efi_tables, "", ""),
> >   };
> >
> >   static int do_efi(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[])
> > @@ -298,5 +335,6 @@ static int do_efi(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[])
> >   U_BOOT_CMD(
> >       efi,     3,      1,      do_efi,
> >       "EFI access",
> > -     "mem [all]        Dump memory information [include boot services]"
> > +     "mem [all]        Dump memory information [include boot services]\n"
> > +     "tables               Dump tables"
> >   );
> > diff --git a/doc/usage/cmd/efi.rst b/doc/usage/cmd/efi.rst
> > index c029c423879..2424d3bb587 100644
> > --- a/doc/usage/cmd/efi.rst
> > +++ b/doc/usage/cmd/efi.rst
> > @@ -10,6 +10,7 @@ Synopsis
> >   ::
> >
> >       efi mem [all]
> > +    efi tables
> >
> >   Description
> >   -----------
> > @@ -54,6 +55,14 @@ Attributes
> >       Shows a code for memory attributes. The key for this is shown below the
> >       table.
> >
> > +efi tables
> > +~~~~~~~~~~
> > +
> > +This shows a list of the EFI tables provided in the system table. These use
> > +GUIDs so it is not possible in general to show the name of a table. But some
> > +effort is made to provide a useful table, where the GUID is known by U-Boot.
> > +
> > +
> >   Example
> >   -------
> >
> > @@ -195,3 +204,16 @@ Example
> >        f: uncached, write-coalescing, write-through, write-back
> >       rf: uncached, write-coalescing, write-through, write-back, needs runtime mapping
> >        1: uncached
> > +
> > +
> > +    => efi tables
> > +    000000001f8eda98  ee4e5898-3914-4259-9d6e-dc7bd79403cf  EFI_LZMA_COMPRESSED
> > +    000000001ff2ace0  05ad34ba-6f02-4214-952e-4da0398e2bb9  EFI_DXE_SERVICES
> > +    000000001f8ea018  7739f24c-93d7-11d4-9a3a-0090273fc14d  EFI_HOB_LIST
> > +    000000001ff2bac0  4c19049f-4137-4dd3-9c10-8b97a83ffdfa  EFI_MEMORY_TYPE
> > +    000000001ff2cb10  49152e77-1ada-4764-b7a2-7afefed95e8b  <NULL>
>
> This is what 'efi tables' / printf("%pUl (%pUs)\n",..). would output for
> an unknown table:
>
> 8868e871-e4f1-11d3-bc22-0080c73c8881 (8868e871-e4f1-11d3-bc22-0080c73c8881)
>
> Maybe uuid_guid_get_str() should return an empty string in case of an
> unknown GUID.

OK

>
> > +    000000001f9ac018  060cc026-4c0d-4dda-8f41-595fef00a502  EFI_MEM_STATUS_CODE_REC
> > +    000000001f9ab000  eb9d2d31-2d88-11d3-9a16-0090273fc14d  EFI_SMBIOS
> > +    000000001fb7e000  eb9d2d30-2d88-11d3-9a16-0090273fc14d  EFI_GUID_EFI_ACPI1
> > +    000000001fb7e014  8868e871-e4f1-11d3-bc22-0080c73c8881  EFI_GUID_EFI_ACPI2
> > +    000000001e550018  dcfa911d-26eb-469f-a220-38b7dc461220  <NULL>
>
> Who would care about the address of the table?

Me when I am looking at them!

Regards,
Simon