Re: [PATCH 1/2] efi: Add efitextmode command for getting/setting the text mode resolution

[Paul Menzel]

Dear Glenn,


Thank you for the patch.

Am 12.05.22 um 05:07 schrieb Glenn Washburn:
> This command is meant to behave similarly to the 'mode' command of the EFI
> Shell application. One difference is that to set the mode the mode number
> is given, not the rows and columns of the desired mode. Also supported are
> the arguments "min" and "max", which set the mode to the minimum and
> maximum mode respectively as calculated by the columns * rows of that mode.

Did you test this also with QEMU and OVMF?


Kind regards,

Paul


> Signed-off-by: Glenn Washburn <development@efficientek.com>
> ---
>   grub-core/Makefile.core.def          |   6 ++
>   grub-core/commands/efi/efitextmode.c | 118 +++++++++++++++++++++++++++
>   2 files changed, 124 insertions(+)
>   create mode 100644 grub-core/commands/efi/efitextmode.c
>
> diff --git a/grub-core/Makefile.core.def b/grub-core/Makefile.core.def
> index 726f51be7..b22e48f0f 100644
> --- a/grub-core/Makefile.core.def
> +++ b/grub-core/Makefile.core.def
> @@ -813,6 +813,12 @@ module = {
>     enable = efi;
>   };
>   
> +module = {
> +  name = efitextmode;
> +  efi = commands/efi/efitextmode.c;
> +  enable = efi;
> +};
> +
>   module = {
>     name = blocklist;
>     common = commands/blocklist.c;
> diff --git a/grub-core/commands/efi/efitextmode.c 
> b/grub-core/commands/efi/efitextmode.c
> new file mode 100644
> index 000000000..fb72aa6f3
> --- /dev/null
> +++ b/grub-core/commands/efi/efitextmode.c
> @@ -0,0 +1,118 @@
> +/* efitextmode.c - command to get/set text mode resolution */
> +/*
> + *  GRUB  --  GRand Unified Bootloader
> + *  Copyright (C) 2003,2005,2006,2007,2009  Free Software Foundation, Inc.
> + *
> + *  GRUB is free software: you can redistribute it and/or modify
> + *  it under the terms of the GNU General Public License as published by
> + *  the Free Software Foundation, either version 3 of the License, or
> + *  (at your option) any later version.
> + *
> + *  GRUB is distributed in the hope that it will be useful,
> + *  but WITHOUT ANY WARRANTY; without even the implied warranty of
> + *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + *  GNU General Public License for more details.
> + *
> + *  You should have received a copy of the GNU General Public License
> + *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
> + */
> +
> +#include <grub/dl.h>
> +#include <grub/misc.h>
> +#include <grub/mm.h>
> +#include <grub/command.h>
> +#include <grub/i18n.h>
> +#include <grub/efi/efi.h>
> +#include <grub/efi/api.h>
> +
> +GRUB_MOD_LICENSE ("GPLv3+");
> +
> +static grub_err_t
> +grub_cmd_efitextmode (grub_command_t cmd __attribute__ ((unused)),
> +                     int argc, char **args)
> +{
> +  grub_efi_simple_text_output_interface_t *o;
> +  unsigned long mode;
> +  const char *p = NULL;
> +  grub_efi_status_t status;
> +  grub_efi_uintn_t columns, rows;
> +  grub_efi_int32_t i;
> +
> +  if (argc > 1)
> +    return grub_error (GRUB_ERR_BAD_ARGUMENT, N_("at most one argument 
> expected"));
> +
> +  o = grub_efi_system_table->con_out;
> +
> +  if (argc == 1)
> +    {
> +      if (grub_strcmp (args[0], "min") == 0)
> +       mode = 0;
> +      else if (grub_strcmp (args[0], "max") == 0)
> +       mode = o->mode->max_mode - 1;
> +      else
> +       {
> +         mode = grub_strtoul (args[0], &p, 0);
> +
> +         if (grub_errno != GRUB_ERR_NONE)
> +           return grub_errno;
> +
> +         if (*args[0] == '\0' || *p != '\0')
> +           return grub_error (GRUB_ERR_BAD_ARGUMENT,
> +                              N_("non-numeric or invalid mode `%s'"),
> +                              args[0]);
> +       }
> +
> +      if (mode < (unsigned long) o->mode->max_mode)
> +       {
> +         if (mode != (unsigned long) o->mode->mode)
> +           {
> +             status = efi_call_2 (o->set_mode, o, (grub_efi_int32_t) mode);
> +             if (status == GRUB_EFI_SUCCESS)
> +               ;
> +             else if (status == GRUB_EFI_DEVICE_ERROR)
> +               return grub_error (GRUB_ERR_BAD_DEVICE,
> +                                  N_("device error: could not set requested"
> +                                     " mode"));
> +             else if (status == GRUB_EFI_UNSUPPORTED)
> +               return grub_error (GRUB_ERR_OUT_OF_RANGE,
> +                                  N_("invalid mode: number not valid"));
> +             else
> +               return grub_error (GRUB_ERR_BAD_OS,
> +                                  N_("unexpected EFI error number: `%u'"),
> +                                  (unsigned) status);
> +           }
> +       }
> +      else
> +       return grub_error (GRUB_ERR_BAD_ARGUMENT,
> +                          N_("invalid mode: `%lu' is greater than maximum"
> +                             " mode `%lu'"),
> +                          mode, (unsigned long) o->mode->max_mode);
> +    }
> +
> +  if (argc == 0)
> +    {
> +      grub_printf_ (N_("Available modes for console output device.\n"));
> +
> +      for (i=0; i < o->mode->max_mode; i++)
> +       if (GRUB_EFI_SUCCESS == efi_call_4 (o->query_mode, o, i,
> +                                           &columns, &rows))
> +         grub_printf_ (N_(" [%lu]  Col %5u Row %5u %c\n"),
> +                       (unsigned long) i, (unsigned) columns, (unsigned) rows,
> +                       (i == o->mode->mode) ? '*' : ' ');
> +    }
> +
> +  return GRUB_ERR_NONE;
> +}
> +
> +static grub_command_t cmd;
> +
> +GRUB_MOD_INIT(cmp)
> +{
> +  cmd = grub_register_command ("efitextmode", grub_cmd_efitextmode,
> +                              N_("[min|max|mode_num]"), N_("Get or set EFI text 
> mode."));
> +}
> +
> +GRUB_MOD_FINI(cmp)
> +{
> +  grub_unregister_command (cmd);
> +}