linux/arch
David Herrmann e3263ab389 x86: provide platform-devices for boot-framebuffers
The current situation regarding boot-framebuffers (VGA, VESA/VBE, EFI) on
x86 causes troubles when loading multiple fbdev drivers. The global
"struct screen_info" does not provide any state-tracking about which
drivers use the FBs. request_mem_region() theoretically works, but
unfortunately vesafb/efifb ignore it due to quirks for broken boards.

Avoid this by creating a platform framebuffer devices with a pointer
to the "struct screen_info" as platform-data. Drivers can now create
platform-drivers and the driver-core will refuse multiple drivers being
active simultaneously.

We keep the screen_info available for backwards-compatibility. Drivers
can be converted in follow-up patches.

Different devices are created for VGA/VESA/EFI FBs to allow multiple
drivers to be loaded on distro kernels. We create:
 - "vesa-framebuffer" for VBE/VESA graphics FBs
 - "efi-framebuffer" for EFI FBs
 - "platform-framebuffer" for everything else
This allows to load vesafb, efifb and others simultaneously and each
picks up only the supported FB types.

Apart from platform-framebuffer devices, this also introduces a
compatibility option for "simple-framebuffer" drivers which recently got
introduced for OF based systems. If CONFIG_X86_SYSFB is selected, we
try to match the screen_info against a simple-framebuffer supported
format. If we succeed, we create a "simple-framebuffer" device instead
of a platform-framebuffer.
This allows to reuse the simplefb.c driver across architectures and also
to introduce a SimpleDRM driver. There is no need to have vesafb.c,
efifb.c, simplefb.c and more just to have architecture specific quirks
in their setup-routines.

Instead, we now move the architecture specific quirks into x86-setup and
provide a generic simple-framebuffer. For backwards-compatibility (if
strange formats are used), we still allow vesafb/efifb to be loaded
simultaneously and pick up all remaining devices.

Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Link: http://lkml.kernel.org/r/1375445127-15480-4-git-send-email-dh.herrmann@gmail.com
Tested-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-08-02 16:17:46 -07:00
..
alpha alpha: Use handle_percpu_irq for the timer interrupt 2013-07-19 13:54:26 -07:00
arc Couple of Platform updates (Device Tree files primarily) given that the 2013-07-10 10:11:26 -07:00
arm Pin control fixes for the v3.11 series: 2013-07-28 18:19:27 -07:00
arm64 arm64: Change kernel stack size to 16K 2013-07-26 13:37:29 +01:00
avr32 net: rename busy poll socket op and globals 2013-07-10 17:08:27 -07:00
blackfin Merge branch 'cpuinit_phase2' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2013-07-18 10:50:26 -07:00
c6x Merge branch 'akpm' (updates from Andrew Morton) 2013-07-03 17:12:13 -07:00
cris cris: delete __cpuinit usage from all cris files 2013-07-14 19:36:54 -04:00
frv frv: delete __cpuinit usage from all frv files 2013-07-14 19:36:55 -04:00
h8300 net: rename busy poll socket op and globals 2013-07-10 17:08:27 -07:00
hexagon hexagon: delete __cpuinit usage from all hexagon files 2013-07-14 19:36:55 -04:00
ia64 net: rename busy poll socket op and globals 2013-07-10 17:08:27 -07:00
m32r m32r: delete __cpuinit usage from all m32r files 2013-07-14 19:36:55 -04:00
m68k Merge branch 'akpm' (updates from Andrew Morton) 2013-07-03 17:12:13 -07:00
metag metag: delete __cpuinit usage from all metag files 2013-07-14 19:36:54 -04:00
microblaze Merge branch 'next' of git://git.monstr.eu/linux-2.6-microblaze 2013-07-10 10:16:07 -07:00
mips Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus 2013-07-19 15:10:01 -07:00
mn10300 net: rename busy poll socket op and globals 2013-07-10 17:08:27 -07:00
openrisc openrisc: delete __cpuinit usage from all openrisc files 2013-07-14 19:36:55 -04:00
parisc parisc: delete __cpuinit usage from all users 2013-07-14 19:36:51 -04:00
powerpc powerpc/perf: BHRB filter configuration should follow the task 2013-07-24 14:42:34 +10:00
s390 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux 2013-07-19 15:08:12 -07:00
score score: delete __cpuinit usage from all score files 2013-07-14 19:36:56 -04:00
sh sh: delete __cpuinit usage from all sh files 2013-07-14 19:36:53 -04:00
sparc sparc: delete __cpuinit/__CPUINIT usage from all users 2013-07-14 19:36:52 -04:00
tile tile: delete __cpuinit usage from all tile files 2013-07-14 19:36:54 -04:00
um um: siginfo cleanup 2013-07-19 11:31:36 +02:00
unicore32 reboot: move arch/x86 reboot= handling to generic kernel 2013-07-09 10:33:29 -07:00
x86 x86: provide platform-devices for boot-framebuffers 2013-08-02 16:17:46 -07:00
xtensa xtensa: delete __cpuinit usage from all xtensa files 2013-07-14 19:36:56 -04:00
.gitignore
Kconfig mm: soft-dirty bits for user memory changes tracking 2013-07-03 16:07:26 -07:00