[PATCH v4 2/3] sysfb: Enable boot time VESA graphic mode selection

[Michal Suchanek <msuchanek@suse.de>]

Since switch to simplefb/simpledrm VESA graphic mode selection with vga=
kernel parameter is no longer available with legacy BIOS.

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

This option is selected by vesafb but not simplefb/simpledrm.

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. Select
the option from sysfb rather than the drivers that depend on it.

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@suse.de>
Acked-by: Borislav Petkov <bp@suse.de>
---
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
v4: Select BOOT_VESA_SUPPORT from sysfb rather than individial sysfb based drivers.
---
 arch/x86/Kconfig            |  6 ++++++
 arch/x86/boot/video-vesa.c  |  4 ++--
 drivers/firmware/Kconfig    |  1 +
 drivers/video/fbdev/Kconfig | 12 ++----------
 4 files changed, 11 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 5265eca74ba1..be42ae6f079e 100644
--- a/drivers/firmware/Kconfig
+++ b/drivers/firmware/Kconfig
@@ -218,6 +218,7 @@ config QCOM_SCM_DOWNLOAD_MODE_DEFAULT
 
 config SYSFB
 	bool
+	select BOOT_VESA_SUPPORT
 
 config SYSFB_SIMPLEFB
 	bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
diff --git a/drivers/video/fbdev/Kconfig b/drivers/video/fbdev/Kconfig
index 907c305caf27..0e25434a71e1 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 +620,6 @@ config FB_VESA
 	select FB_CFB_FILLRECT
 	select FB_CFB_COPYAREA
 	select FB_CFB_IMAGEBLIT
-	select FB_BOOT_VESA_SUPPORT
 	select SYSFB
 	help
 	  This is the frame buffer device driver for generic VESA 2.0
@@ -1053,7 +1045,7 @@ 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
@@ -1380,7 +1372,7 @@ 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
-- 
2.34.1