[PATCH v3] simplefb: Enable boot time VESA graphic mode selection.

From: Michal Suchanek
Date: Fri Feb 18 2022 - 11:04:50 EST


Since switch to simplefb/simpledrm VESA graphic modes are no longer
available with legacy BIOS.

The x86 realmode boot code enables the VESA graphic modes when option
FB_BOOT_VESA_SUPPORT is enabled.

To enable use of VESA modes with simplefb in legacy BIOS boot mode drop
dependency of BOOT_VESA_SUPPORT on FB, also drop the FB_ prefix, and
select the option when simplefb enabled on x86.

The BOOT_VESA_SUPPORT is not specific to framebuffer but rather to x86
platform, move it from fbdev to x86 Kconfig.

Fixes: e3263ab389a7 ("x86: provide platform-devices for boot-framebuffers")
Signed-off-by: Michal Suchanek <msuchanek@xxxxxxx>
---
v2: Select BOOT_VESA_SUPPORT from simplefb rather than simpledrm. The
simpledrm driver uses the firmware provided video modes only indirectly
through simplefb, and both can be enabled independently.
v3: Move BOOT_VESA_SUPPORT from fbdev to x86
---
arch/x86/Kconfig | 6 ++++++
arch/x86/boot/video-vesa.c | 4 ++--
drivers/firmware/Kconfig | 1 +
drivers/video/fbdev/Kconfig | 13 +++----------
4 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 9f5bd41bf660..cceb1aab0486 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -942,6 +942,12 @@ config GART_IOMMU

If unsure, say Y.

+config BOOT_VESA_SUPPORT
+ bool
+ help
+ If true, at least one selected framebuffer driver can take advantage
+ of VESA video modes set at an early boot stage via the vga= parameter.
+
config MAXSMP
bool "Enable Maximum number of SMP Processors and NUMA Nodes"
depends on X86_64 && SMP && DEBUG_KERNEL
diff --git a/arch/x86/boot/video-vesa.c b/arch/x86/boot/video-vesa.c
index 7e185977a984..c2c6d35e3a43 100644
--- a/arch/x86/boot/video-vesa.c
+++ b/arch/x86/boot/video-vesa.c
@@ -83,7 +83,7 @@ static int vesa_probe(void)
(vminfo.memory_layout == 4 ||
vminfo.memory_layout == 6) &&
vminfo.memory_planes == 1) {
-#ifdef CONFIG_FB_BOOT_VESA_SUPPORT
+#ifdef CONFIG_BOOT_VESA_SUPPORT
/* Graphics mode, color, linear frame buffer
supported. Only register the mode if
if framebuffer is configured, however,
@@ -121,7 +121,7 @@ static int vesa_set_mode(struct mode_info *mode)
if ((vminfo.mode_attr & 0x15) == 0x05) {
/* It's a supported text mode */
is_graphic = 0;
-#ifdef CONFIG_FB_BOOT_VESA_SUPPORT
+#ifdef CONFIG_BOOT_VESA_SUPPORT
} else if ((vminfo.mode_attr & 0x99) == 0x99) {
/* It's a graphics mode with linear frame buffer */
is_graphic = 1;
diff --git a/drivers/firmware/Kconfig b/drivers/firmware/Kconfig
index 75cb91055c17..ad64f3a6f54f 100644
--- a/drivers/firmware/Kconfig
+++ b/drivers/firmware/Kconfig
@@ -224,6 +224,7 @@ config SYSFB
config SYSFB_SIMPLEFB
bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
depends on SYSFB
+ select BOOT_VESA_SUPPORT
help
Firmwares often provide initial graphics framebuffers so the BIOS,
bootloader or kernel can show basic video-output during boot for
diff --git a/drivers/video/fbdev/Kconfig b/drivers/video/fbdev/Kconfig
index 6ed5e608dd04..5bdd303b5268 100644
--- a/drivers/video/fbdev/Kconfig
+++ b/drivers/video/fbdev/Kconfig
@@ -66,13 +66,6 @@ config FB_DDC
select I2C_ALGOBIT
select I2C

-config FB_BOOT_VESA_SUPPORT
- bool
- depends on FB
- help
- If true, at least one selected framebuffer driver can take advantage
- of VESA video modes set at an early boot stage via the vga= parameter.
-
config FB_CFB_FILLRECT
tristate
depends on FB
@@ -627,7 +620,7 @@ config FB_VESA
select FB_CFB_FILLRECT
select FB_CFB_COPYAREA
select FB_CFB_IMAGEBLIT
- select FB_BOOT_VESA_SUPPORT
+ select BOOT_VESA_SUPPORT
help
This is the frame buffer device driver for generic VESA 2.0
compliant graphic cards. The older VESA 1.2 cards are not supported.
@@ -1051,7 +1044,7 @@ config FB_INTEL
select FB_CFB_FILLRECT
select FB_CFB_COPYAREA
select FB_CFB_IMAGEBLIT
- select FB_BOOT_VESA_SUPPORT if FB_INTEL = y
+ select BOOT_VESA_SUPPORT if FB_INTEL = y
depends on !DRM_I915
help
This driver supports the on-board graphics built in to the Intel
@@ -1378,7 +1371,7 @@ config FB_SIS
select FB_CFB_FILLRECT
select FB_CFB_COPYAREA
select FB_CFB_IMAGEBLIT
- select FB_BOOT_VESA_SUPPORT if FB_SIS = y
+ select BOOT_VESA_SUPPORT if FB_SIS = y
select FB_SIS_300 if !FB_SIS_315
help
This is the frame buffer device driver for the SiS 300, 315, 330
--
2.31.1