From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001

From: Hans de Goede <hdegoede@redhat.com>

Date: Tue, 6 Mar 2018 17:11:15 +0100

Subject: [PATCH] EFI: console: Do not set text-mode until we actually need it

If we're running with a hidden menu we may never need text mode, so do not

change the video-mode to text until we actually need it.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>

---

 grub-core/term/efi/console.c | 65 ++++++++++++++++++++++++++++++--------------

 1 file changed, 44 insertions(+), 21 deletions(-)

diff --git a/grub-core/term/efi/console.c b/grub-core/term/efi/console.c

index 4840cc59d..051633d71 100644

--- a/grub-core/term/efi/console.c

+++ b/grub-core/term/efi/console.c

@@ -24,6 +24,11 @@

 #include <grub/efi/api.h>

 #include <grub/efi/console.h>

+static grub_err_t grub_prepare_for_text_output(struct grub_term_output *term);

+

+static int text_mode_available = -1;

+static int text_colorstate = -1;

+

 static grub_uint32_t

 map_char (grub_uint32_t c)

 {

@@ -66,14 +71,14 @@ map_char (grub_uint32_t c)

 }

 static void

-grub_console_putchar (struct grub_term_output *term __attribute__ ((unused)),

+grub_console_putchar (struct grub_term_output *term,

 		      const struct grub_unicode_glyph *c)

 {

   grub_efi_char16_t str[2 + 30];

   grub_efi_simple_text_output_interface_t *o;

   unsigned i, j;

-  if (grub_efi_is_finished)

+  if (grub_prepare_for_text_output (term))

     return;

   o = grub_efi_system_table->con_out;

@@ -223,14 +228,15 @@ grub_console_getkey (struct grub_term_input *term)

 }

 static struct grub_term_coordinate

-grub_console_getwh (struct grub_term_output *term __attribute__ ((unused)))

+grub_console_getwh (struct grub_term_output *term)

 {

   grub_efi_simple_text_output_interface_t *o;

   grub_efi_uintn_t columns, rows;

   o = grub_efi_system_table->con_out;

-  if (grub_efi_is_finished || efi_call_4 (o->query_mode, o, o->mode->mode,

-					  &columns, &rows) != GRUB_EFI_SUCCESS)

+  if (grub_prepare_for_text_output (term) != GRUB_ERR_NONE ||

+      efi_call_4 (o->query_mode, o, o->mode->mode,

+		  &columns, &rows) != GRUB_EFI_SUCCESS)

     {

       /* Why does this fail?  */

       columns = 80;

@@ -245,7 +251,7 @@ grub_console_getxy (struct grub_term_output *term __attribute__ ((unused)))

 {

   grub_efi_simple_text_output_interface_t *o;

-  if (grub_efi_is_finished)

+  if (grub_efi_is_finished || text_mode_available != 1)

     return (struct grub_term_coordinate) { 0, 0 };

   o = grub_efi_system_table->con_out;

@@ -253,12 +259,12 @@ grub_console_getxy (struct grub_term_output *term __attribute__ ((unused)))

 }

 static void

-grub_console_gotoxy (struct grub_term_output *term __attribute__ ((unused)),

+grub_console_gotoxy (struct grub_term_output *term,

 		     struct grub_term_coordinate pos)

 {

   grub_efi_simple_text_output_interface_t *o;

-  if (grub_efi_is_finished)

+  if (grub_prepare_for_text_output (term))

     return;

   o = grub_efi_system_table->con_out;

@@ -271,7 +277,7 @@ grub_console_cls (struct grub_term_output *term __attribute__ ((unused)))

   grub_efi_simple_text_output_interface_t *o;

   grub_efi_int32_t orig_attr;

-  if (grub_efi_is_finished)

+  if (grub_efi_is_finished || text_mode_available != 1)

     return;

   o = grub_efi_system_table->con_out;

@@ -291,6 +297,12 @@ grub_console_setcolorstate (struct grub_term_output *term

   if (grub_efi_is_finished)

     return;

+  if (text_mode_available != 1) {

+    /* Avoid "color_normal" environment writes causing a switch to textmode */

+    text_colorstate = state;

+    return;

+  }

+

   o = grub_efi_system_table->con_out;

   switch (state) {

@@ -315,7 +327,7 @@ grub_console_setcursor (struct grub_term_output *term __attribute__ ((unused)),

 {

   grub_efi_simple_text_output_interface_t *o;

-  if (grub_efi_is_finished)

+  if (grub_efi_is_finished || text_mode_available != 1)

     return;

   o = grub_efi_system_table->con_out;

@@ -323,18 +335,38 @@ grub_console_setcursor (struct grub_term_output *term __attribute__ ((unused)),

 }

 static grub_err_t

-grub_efi_console_output_init (struct grub_term_output *term)

+grub_prepare_for_text_output(struct grub_term_output *term)

 {

-  grub_efi_set_text_mode (1);

+  if (grub_efi_is_finished)

+    return GRUB_ERR_BAD_DEVICE;

+

+  if (text_mode_available != -1)

+    return text_mode_available ? 0 : GRUB_ERR_BAD_DEVICE;

+

+  if (! grub_efi_set_text_mode (1))

+    {

+      /* This really should never happen */

+      grub_error (GRUB_ERR_BAD_DEVICE, "cannot set text mode");

+      text_mode_available = 0;

+      return GRUB_ERR_BAD_DEVICE;

+    }

+

   grub_console_setcursor (term, 1);

+  if (text_colorstate != -1)

+    grub_console_setcolorstate (term, text_colorstate);

+  text_mode_available = 1;

   return 0;

 }

 static grub_err_t

 grub_efi_console_output_fini (struct grub_term_output *term)

 {

+  if (text_mode_available != 1)

+    return 0;

+

   grub_console_setcursor (term, 0);

   grub_efi_set_text_mode (0);

+  text_mode_available = -1;

   return 0;

 }

@@ -348,7 +380,6 @@ static struct grub_term_input grub_console_term_input =

 static struct grub_term_output grub_console_term_output =

   {

     .name = "console",

-    .init = grub_efi_console_output_init,

     .fini = grub_efi_console_output_fini,

     .putchar = grub_console_putchar,

     .getwh = grub_console_getwh,

@@ -364,14 +395,6 @@ static struct grub_term_output grub_console_term_output =

 void

 grub_console_init (void)

 {

-  /* FIXME: it is necessary to consider the case where no console control

-     is present but the default is already in text mode.  */

-  if (! grub_efi_set_text_mode (1))

-    {

-      grub_error (GRUB_ERR_BAD_DEVICE, "cannot set text mode");

-      return;

-    }

-

   grub_term_register_output ("console", &grub_console_term_output);

   grub_term_register_input ("console", &grub_console_term_input);

 }