[Xen-devel] [PATCH v2 0/3] x86: S3 resume adjustments

Jan Beulich posted 3 patches 4 years, 7 months ago
Only 0 patches received!
[Xen-devel] [PATCH v2 0/3] x86: S3 resume adjustments
Posted by Jan Beulich 4 years, 7 months ago
1: x86/ACPI: restore VESA mode upon resume from S3
2: x86: a little bit of 16-bit video mode setting code cleanup
3: x86: shrink video_{flags,mode} to {8,16} bits

Patch 1 is meant to address an issue I've observed while testing
the v1 patch that was committed already, and patch 2 is simply a
collection of misc changes noticed while putting together patch 1
as possibly worthwhile to make. Patch 3 is a result of v1 review
feedback.

Jan

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Re: [Xen-devel] [PATCH v2 0/3] x86: S3 resume adjustments
Posted by Jan Beulich 4 years, 7 months ago
On 30.08.2019 15:38, Jan Beulich wrote:
> 1: x86/ACPI: restore VESA mode upon resume from S3
> 2: x86: a little bit of 16-bit video mode setting code cleanup
> 3: x86: shrink video_{flags,mode} to {8,16} bits

And (sadly) the patches as attachments again.

Jan
x86/ACPI: restore VESA mode upon resume from S3

In order for "acpi_sleep=s3_mode" to have any effect, we should record
the video mode we switched to during boot. Since right now there's mode
setting code for VESA modes only in the resume case, record the mode
just in that one case.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
---
I'm wondering actually whether the user having to explicitly request the
mode restoration is a good model: Why would we _not_ want to restore the
mode we've set during boot? In the worst case Dom0 kernel or X will
change the mode another time.

--- a/xen/arch/x86/boot/video.S
+++ b/xen/arch/x86/boot/video.S
@@ -455,14 +455,17 @@ check_vesa:
         cmpb    $0x99, %al
         jnz     _setbad                 # Doh! No linear frame buffer.
 
+        pushw   %bx
         subb    $VIDEO_FIRST_VESA>>8, %bh
         orw     $0x4000, %bx            # Use linear frame buffer
         movw    $0x4f02, %ax            # VESA BIOS mode set call
         int     $0x10
+        popw    %bx
         cmpw    $0x004f, %ax            # AL=4f if implemented
         jnz     _setbad                 # AH=0 if OK
 
         movb    $1, bootsym(graphic_mode)  # flag graphic mode
+        movw    %bx, bootsym(video_mode)
         stc
         ret
 
x86: a little bit of 16-bit video mode setting code cleanup

To "compensate" for the code size growth by an earlier change:
- drop "trampoline" labels (in almost all cases the target label is
  reachable with an 8-bit-displacement branch anyway, and a single 16-
  bit-displacement branch is still better than a pair of two branches)
- drop an entirely dead insn from wakeup.S:mode_setw
- reduce code size in a few other (obvious I hope) cases, by more
  suitable insn/operands selection

Also drop redundant #define-s (move suitable #include a little earlier
instead) and add two alignment directives.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
---
v2: Minor adjustment to description. Re-base.

--- a/xen/arch/x86/boot/trampoline.S
+++ b/xen/arch/x86/boot/trampoline.S
@@ -176,6 +176,7 @@ start64:
 
         jmpq    *%rdi
 
+#include "video.h"
 #include "wakeup.S"
 
         .balign 8
@@ -282,8 +283,6 @@ trampoline_boot_cpu_entry:
         /* Jump to the common bootstrap entry point. */
         jmp     trampoline_protmode_entry
 
-#include "video.h"
-
         .align  2
 /* Keep in sync with cmdline.c:early_boot_opts_t type! */
 early_boot_opts:
--- a/xen/arch/x86/boot/video.S
+++ b/xen/arch/x86/boot/video.S
@@ -384,9 +384,6 @@ lmbad:  leaw    bootsym(unknt), %si
         jmp     mode_menu
 lmdef:  ret
 
-_setrec:    jmp setrec                  # Ugly...
-_set_80x25: jmp set_80x25
-
 # Setting of user mode (AX=mode ID) => CF=success
 mode_set:
         movw    %ax, bootsym(boot_vid_mode)
@@ -396,7 +393,7 @@ mode_set:
         je      setvesabysize
 
         testb   $VIDEO_RECALC>>8, %ah
-        jnz     _setrec
+        jnz     setrec
 
         cmpb    $VIDEO_FIRST_SPECIAL>>8, %ah
         jz      setspc
@@ -421,7 +418,7 @@ setspc: xorb    %bh, %bh
 
 setmenu:
         orb     %al, %al                # 80x25 is an exception
-        jz      _set_80x25
+        jz      set_80x25
         
         pushw   %bx                     # Set mode chosen from menu
         call    mode_table              # Build the mode table
@@ -441,36 +438,32 @@ check_vesa:
         cmpw    $0x004f, %ax
         jnz     setbad
 
-        leaw    vesa_mode_info, %di
-        subb    $VIDEO_FIRST_VESA>>8, %bh
-        movw    %bx, %cx                # Get mode information structure
+        leaw    vesa_mode_info, %di     # Get mode information structure
+        leaw    -VIDEO_FIRST_VESA(%bx), %cx
         movw    $0x4f01, %ax
         int     $0x10
-        addb    $VIDEO_FIRST_VESA>>8, %bh
         cmpw    $0x004f, %ax
         jnz     setbad
 
         movb    (%di), %al              # Check mode attributes.
         andb    $0x99, %al
         cmpb    $0x99, %al
-        jnz     _setbad                 # Doh! No linear frame buffer.
+        jnz     setbad                  # Doh! No linear frame buffer.
 
         pushw   %bx
         subb    $VIDEO_FIRST_VESA>>8, %bh
-        orw     $0x4000, %bx            # Use linear frame buffer
+        orb     $0x40, %bh              # Use linear frame buffer
         movw    $0x4f02, %ax            # VESA BIOS mode set call
         int     $0x10
         popw    %bx
         cmpw    $0x004f, %ax            # AL=4f if implemented
-        jnz     _setbad                 # AH=0 if OK
+        jnz     setbad                  # AH=0 if OK
 
         movb    $1, bootsym(graphic_mode)  # flag graphic mode
         movw    %bx, bootsym(video_mode)
         stc
         ret
 
-_setbad: jmp    setbad                  # Ugly...
-
 # Recalculate vertical display end registers -- this fixes various
 # inconsistencies of extended modes on many adapters. Called when
 # the VIDEO_RECALC flag is set in the mode ID.
@@ -515,7 +508,7 @@ setvesabysize:
         leaw    modelist,%si
 1:      add     $8,%si
         cmpw    $ASK_VGA,-8(%si)        # End?
-        je      _setbad
+        je      setbad
         movw    -6(%si),%ax
         cmpw    %ax,bootsym(vesa_size)+0
         jne     1b
@@ -948,6 +941,7 @@ store_edid:
 #endif
         ret
 
+                .p2align 1
 mt_end:         .word   0       # End of video mode table if built
 edit_buf:       .space  6       # Line editor buffer
 card_name:      .word   0       # Pointer to adapter name
@@ -991,6 +985,7 @@ vesa_name:      .asciz  "VESA"
 
 name_bann:      .asciz  "Video adapter: "
 
+                .p2align 1
 force_size:     .word   0       # Use this size instead of the one in BIOS vars
 
 GLOBAL(boot_vid_info)
--- a/xen/arch/x86/boot/wakeup.S
+++ b/xen/arch/x86/boot/wakeup.S
@@ -30,7 +30,7 @@ ENTRY(wakeup_start)
         jne     bogus_real_magic
 
         # for acpi_sleep=s3_bios
-        testl   $1, wakesym(video_flags)
+        testb   $1, wakesym(video_flags)
         jz      1f
         lcall   $0xc000, $3
         movw    %cs, %ax        # In case messed by BIOS
@@ -38,9 +38,9 @@ ENTRY(wakeup_start)
         movw    %ax, %ss        # Need this? How to ret if clobbered?
 
 1:      # for acpi_sleep=s3_mode
-        testl   $2, wakesym(video_flags)
+        testb   $2, wakesym(video_flags)
         jz      1f
-        movl    wakesym(video_mode), %eax
+        movw    wakesym(video_mode), %ax
         call    mode_setw
 
 1:      # Show some progress if VGA is resumed
@@ -56,48 +56,26 @@ ENTRY(wakeup_start)
 
         ljmpl   $BOOT_CS32, $bootsym_rel(wakeup_32, 6)
 
-/* This code uses an extended set of video mode numbers. These include:
- * Aliases for standard modes
- *      NORMAL_VGA (-1)
- *      EXTENDED_VGA (-2)
- *      ASK_VGA (-3)
- * Video modes numbered by menu position -- NOT RECOMMENDED because of lack
- * of compatibility when extending the table. These are between 0x00 and 0xff.
- */
-#define VIDEO_FIRST_MENU 0x0000
-
-/* Standard BIOS video modes (BIOS number + 0x0100) */
-#define VIDEO_FIRST_BIOS 0x0100
-
-/* VESA BIOS video modes (VESA number + 0x0200) */
-#define VIDEO_FIRST_VESA 0x0200
-
-/* Video7 special modes (BIOS number + 0x0900) */
-#define VIDEO_FIRST_V7 0x0900
-
 # Setting of user mode (AX=mode ID) => CF=success
 mode_setw:
         movw    %ax, %bx
         cmpb    $VIDEO_FIRST_VESA>>8, %ah
         jnc     check_vesaw
-        decb    %ah
 
 setbadw: clc
         ret
 
 check_vesaw:
         subb    $VIDEO_FIRST_VESA>>8, %bh
-        orw     $0x4000, %bx                    # Use linear frame buffer
+        orb     $0x40, %bh                      # Use linear frame buffer
         movw    $0x4f02, %ax                    # VESA BIOS mode set call
         int     $0x10
         cmpw    $0x004f, %ax                    # AL=4f if implemented
-        jnz     _setbadw                        # AH=0 if OK
+        jnz     setbadw                         # AH=0 if OK
 
         stc
         ret
 
-_setbadw: jmp    setbadw
-
 bogus_real_magic:
         movw    $0x0e00 + 'B', %fs:(0x12)
         jmp     bogus_real_magic
x86: shrink video_{flags,mode} to {8,16} bits

We really don't need them to be any wider.

Also remove the C level declaration (and hence also the GLOBAL) of
video_mode altogether; it's used in assembly code only.

Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
---
v2: New.

--- a/xen/arch/x86/boot/wakeup.S
+++ b/xen/arch/x86/boot/wakeup.S
@@ -82,10 +82,9 @@ bogus_real_magic:
 
         .align 4
 real_magic:     .long 0x12345678
-GLOBAL(video_mode)
-        .long 0
+video_mode:     .word 0
 GLOBAL(video_flags)
-        .long 0
+        .byte 0
 
         .code32
 
--- a/xen/include/asm-x86/config.h
+++ b/xen/include/asm-x86/config.h
@@ -99,7 +99,9 @@ extern char trampoline_realmode_entry[];
 extern unsigned int trampoline_xen_phys_start;
 extern unsigned char trampoline_cpu_started;
 extern char wakeup_start[];
-extern unsigned int video_mode, video_flags;
+
+extern unsigned char video_flags;
+
 extern unsigned short boot_edid_caps;
 extern unsigned char boot_edid_info[128];
 #endif
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[Xen-devel] [PATCH v2 1/3] x86/ACPI: restore VESA mode upon resume from S3
Posted by Jan Beulich 4 years, 7 months ago
In order for "acpi_sleep=s3_mode" to have any effect, we should record
the video mode we switched to during boot. Since right now there's mode
setting code for VESA modes only in the resume case, record the mode
just in that one case.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
---
I'm wondering actually whether the user having to explicitly request the
mode restoration is a good model: Why would we _not_ want to restore the
mode we've set during boot? In the worst case Dom0 kernel or X will
change the mode another time.

--- a/xen/arch/x86/boot/video.S
+++ b/xen/arch/x86/boot/video.S
@@ -455,14 +455,17 @@ check_vesa:
         cmpb    $0x99, %al
         jnz     _setbad                 # Doh! No linear frame buffer.
 
+        pushw   %bx
         subb    $VIDEO_FIRST_VESA>>8, %bh
         orw     $0x4000, %bx            # Use linear frame buffer
         movw    $0x4f02, %ax            # VESA BIOS mode set call
         int     $0x10
+        popw    %bx
         cmpw    $0x004f, %ax            # AL=4f if implemented
         jnz     _setbad                 # AH=0 if OK
 
         movb    $1, bootsym(graphic_mode)  # flag graphic mode
+        movw    %bx, bootsym(video_mode)
         stc
         ret
 


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Re: [Xen-devel] [PATCH v2 1/3] x86/ACPI: restore VESA mode upon resume from S3
Posted by Andrew Cooper 4 years, 7 months ago
On 30/08/2019 14:41, Jan Beulich wrote:
> In order for "acpi_sleep=s3_mode" to have any effect, we should record
> the video mode we switched to during boot. Since right now there's mode
> setting code for VESA modes only in the resume case, record the mode
> just in that one case.
>
> Signed-off-by: Jan Beulich <jbeulich@suse.com>

Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>

> ---
> I'm wondering actually whether the user having to explicitly request the
> mode restoration is a good model: Why would we _not_ want to restore the
> mode we've set during boot? In the worst case Dom0 kernel or X will
> change the mode another time.

By this, I presume you mean drop the acpi_sleep option entirely?

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Re: [Xen-devel] [PATCH v2 1/3] x86/ACPI: restore VESA mode upon resume from S3
Posted by Jan Beulich 4 years, 7 months ago
On 02.09.2019 12:42, Andrew Cooper wrote:
> On 30/08/2019 14:41, Jan Beulich wrote:
>> In order for "acpi_sleep=s3_mode" to have any effect, we should record
>> the video mode we switched to during boot. Since right now there's mode
>> setting code for VESA modes only in the resume case, record the mode
>> just in that one case.
>>
>> Signed-off-by: Jan Beulich <jbeulich@suse.com>
> 
> Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>

Thanks.

>> ---
>> I'm wondering actually whether the user having to explicitly request the
>> mode restoration is a good model: Why would we _not_ want to restore the
>> mode we've set during boot? In the worst case Dom0 kernel or X will
>> change the mode another time.
> 
> By this, I presume you mean drop the acpi_sleep option entirely?

Well, no, not drop it altogether. But invert the s3_mode default.

Jan


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[Xen-devel] [PATCH v2 2/3] x86: a little bit of 16-bit video mode setting code cleanup
Posted by Jan Beulich 4 years, 7 months ago
To "compensate" for the code size growth by an earlier change:
- drop "trampoline" labels (in almost all cases the target label is
  reachable with an 8-bit-displacement branch anyway, and a single 16-
  bit-displacement branch is still better than a pair of two branches)
- drop an entirely dead insn from wakeup.S:mode_setw
- reduce code size in a few other (obvious I hope) cases, by more
  suitable insn/operands selection

Also drop redundant #define-s (move suitable #include a little earlier
instead) and add two alignment directives.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
---
v2: Minor adjustment to description. Re-base.

--- a/xen/arch/x86/boot/trampoline.S
+++ b/xen/arch/x86/boot/trampoline.S
@@ -176,6 +176,7 @@ start64:
 
         jmpq    *%rdi
 
+#include "video.h"
 #include "wakeup.S"
 
         .balign 8
@@ -282,8 +283,6 @@ trampoline_boot_cpu_entry:
         /* Jump to the common bootstrap entry point. */
         jmp     trampoline_protmode_entry
 
-#include "video.h"
-
         .align  2
 /* Keep in sync with cmdline.c:early_boot_opts_t type! */
 early_boot_opts:
--- a/xen/arch/x86/boot/video.S
+++ b/xen/arch/x86/boot/video.S
@@ -384,9 +384,6 @@ lmbad:  leaw    bootsym(unknt), %si
         jmp     mode_menu
 lmdef:  ret
 
-_setrec:    jmp setrec                  # Ugly...
-_set_80x25: jmp set_80x25
-
 # Setting of user mode (AX=mode ID) => CF=success
 mode_set:
         movw    %ax, bootsym(boot_vid_mode)
@@ -396,7 +393,7 @@ mode_set:
         je      setvesabysize
 
         testb   $VIDEO_RECALC>>8, %ah
-        jnz     _setrec
+        jnz     setrec
 
         cmpb    $VIDEO_FIRST_SPECIAL>>8, %ah
         jz      setspc
@@ -421,7 +418,7 @@ setspc: xorb    %bh, %bh
 
 setmenu:
         orb     %al, %al                # 80x25 is an exception
-        jz      _set_80x25
+        jz      set_80x25
         
         pushw   %bx                     # Set mode chosen from menu
         call    mode_table              # Build the mode table
@@ -441,36 +438,32 @@ check_vesa:
         cmpw    $0x004f, %ax
         jnz     setbad
 
-        leaw    vesa_mode_info, %di
-        subb    $VIDEO_FIRST_VESA>>8, %bh
-        movw    %bx, %cx                # Get mode information structure
+        leaw    vesa_mode_info, %di     # Get mode information structure
+        leaw    -VIDEO_FIRST_VESA(%bx), %cx
         movw    $0x4f01, %ax
         int     $0x10
-        addb    $VIDEO_FIRST_VESA>>8, %bh
         cmpw    $0x004f, %ax
         jnz     setbad
 
         movb    (%di), %al              # Check mode attributes.
         andb    $0x99, %al
         cmpb    $0x99, %al
-        jnz     _setbad                 # Doh! No linear frame buffer.
+        jnz     setbad                  # Doh! No linear frame buffer.
 
         pushw   %bx
         subb    $VIDEO_FIRST_VESA>>8, %bh
-        orw     $0x4000, %bx            # Use linear frame buffer
+        orb     $0x40, %bh              # Use linear frame buffer
         movw    $0x4f02, %ax            # VESA BIOS mode set call
         int     $0x10
         popw    %bx
         cmpw    $0x004f, %ax            # AL=4f if implemented
-        jnz     _setbad                 # AH=0 if OK
+        jnz     setbad                  # AH=0 if OK
 
         movb    $1, bootsym(graphic_mode)  # flag graphic mode
         movw    %bx, bootsym(video_mode)
         stc
         ret
 
-_setbad: jmp    setbad                  # Ugly...
-
 # Recalculate vertical display end registers -- this fixes various
 # inconsistencies of extended modes on many adapters. Called when
 # the VIDEO_RECALC flag is set in the mode ID.
@@ -515,7 +508,7 @@ setvesabysize:
         leaw    modelist,%si
 1:      add     $8,%si
         cmpw    $ASK_VGA,-8(%si)        # End?
-        je      _setbad
+        je      setbad
         movw    -6(%si),%ax
         cmpw    %ax,bootsym(vesa_size)+0
         jne     1b
@@ -948,6 +941,7 @@ store_edid:
 #endif
         ret
 
+                .p2align 1
 mt_end:         .word   0       # End of video mode table if built
 edit_buf:       .space  6       # Line editor buffer
 card_name:      .word   0       # Pointer to adapter name
@@ -991,6 +985,7 @@ vesa_name:      .asciz  "VESA"
 
 name_bann:      .asciz  "Video adapter: "
 
+                .p2align 1
 force_size:     .word   0       # Use this size instead of the one in BIOS vars
 
 GLOBAL(boot_vid_info)
--- a/xen/arch/x86/boot/wakeup.S
+++ b/xen/arch/x86/boot/wakeup.S
@@ -30,7 +30,7 @@ ENTRY(wakeup_start)
         jne     bogus_real_magic
 
         # for acpi_sleep=s3_bios
-        testl   $1, wakesym(video_flags)
+        testb   $1, wakesym(video_flags)
         jz      1f
         lcall   $0xc000, $3
         movw    %cs, %ax        # In case messed by BIOS
@@ -38,9 +38,9 @@ ENTRY(wakeup_start)
         movw    %ax, %ss        # Need this? How to ret if clobbered?
 
 1:      # for acpi_sleep=s3_mode
-        testl   $2, wakesym(video_flags)
+        testb   $2, wakesym(video_flags)
         jz      1f
-        movl    wakesym(video_mode), %eax
+        movw    wakesym(video_mode), %ax
         call    mode_setw
 
 1:      # Show some progress if VGA is resumed
@@ -56,48 +56,26 @@ ENTRY(wakeup_start)
 
         ljmpl   $BOOT_CS32, $bootsym_rel(wakeup_32, 6)
 
-/* This code uses an extended set of video mode numbers. These include:
- * Aliases for standard modes
- *      NORMAL_VGA (-1)
- *      EXTENDED_VGA (-2)
- *      ASK_VGA (-3)
- * Video modes numbered by menu position -- NOT RECOMMENDED because of lack
- * of compatibility when extending the table. These are between 0x00 and 0xff.
- */
-#define VIDEO_FIRST_MENU 0x0000
-
-/* Standard BIOS video modes (BIOS number + 0x0100) */
-#define VIDEO_FIRST_BIOS 0x0100
-
-/* VESA BIOS video modes (VESA number + 0x0200) */
-#define VIDEO_FIRST_VESA 0x0200
-
-/* Video7 special modes (BIOS number + 0x0900) */
-#define VIDEO_FIRST_V7 0x0900
-
 # Setting of user mode (AX=mode ID) => CF=success
 mode_setw:
         movw    %ax, %bx
         cmpb    $VIDEO_FIRST_VESA>>8, %ah
         jnc     check_vesaw
-        decb    %ah
 
 setbadw: clc
         ret
 
 check_vesaw:
         subb    $VIDEO_FIRST_VESA>>8, %bh
-        orw     $0x4000, %bx                    # Use linear frame buffer
+        orb     $0x40, %bh                      # Use linear frame buffer
         movw    $0x4f02, %ax                    # VESA BIOS mode set call
         int     $0x10
         cmpw    $0x004f, %ax                    # AL=4f if implemented
-        jnz     _setbadw                        # AH=0 if OK
+        jnz     setbadw                         # AH=0 if OK
 
         stc
         ret
 
-_setbadw: jmp    setbadw
-
 bogus_real_magic:
         movw    $0x0e00 + 'B', %fs:(0x12)
         jmp     bogus_real_magic


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Re: [Xen-devel] [PATCH v2 2/3] x86: a little bit of 16-bit video mode setting code cleanup
Posted by Andrew Cooper 4 years, 7 months ago
On 30/08/2019 14:41, Jan Beulich wrote:
> To "compensate" for the code size growth by an earlier change:
> - drop "trampoline" labels (in almost all cases the target label is
>   reachable with an 8-bit-displacement branch anyway, and a single 16-
>   bit-displacement branch is still better than a pair of two branches)
> - drop an entirely dead insn from wakeup.S:mode_setw
> - reduce code size in a few other (obvious I hope) cases, by more
>   suitable insn/operands selection
>
> Also drop redundant #define-s (move suitable #include a little earlier
> instead) and add two alignment directives.
>
> Signed-off-by: Jan Beulich <jbeulich@suse.com>

Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>

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[Xen-devel] [PATCH v2 3/3] x86: shrink video_{flags, mode} to {8, 16} bits
Posted by Jan Beulich 4 years, 7 months ago
We really don't need them to be any wider.

Also remove the C level declaration (and hence also the GLOBAL) of
video_mode altogether; it's used in assembly code only.

Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
---
v2: New.

--- a/xen/arch/x86/boot/wakeup.S
+++ b/xen/arch/x86/boot/wakeup.S
@@ -82,10 +82,9 @@ bogus_real_magic:
 
         .align 4
 real_magic:     .long 0x12345678
-GLOBAL(video_mode)
-        .long 0
+video_mode:     .word 0
 GLOBAL(video_flags)
-        .long 0
+        .byte 0
 
         .code32
 
--- a/xen/include/asm-x86/config.h
+++ b/xen/include/asm-x86/config.h
@@ -99,7 +99,9 @@ extern char trampoline_realmode_entry[];
 extern unsigned int trampoline_xen_phys_start;
 extern unsigned char trampoline_cpu_started;
 extern char wakeup_start[];
-extern unsigned int video_mode, video_flags;
+
+extern unsigned char video_flags;
+
 extern unsigned short boot_edid_caps;
 extern unsigned char boot_edid_info[128];
 #endif


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Re: [Xen-devel] [PATCH v2 3/3] x86: shrink video_{flags, mode} to {8, 16} bits
Posted by Andrew Cooper 4 years, 7 months ago
On 30/08/2019 14:42, Jan Beulich wrote:
> We really don't need them to be any wider.
>
> Also remove the C level declaration (and hence also the GLOBAL) of
> video_mode altogether; it's used in assembly code only.
>
> Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com>
> Signed-off-by: Jan Beulich <jbeulich@suse.com>

Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>

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