IORESOURCE_BUSY is used to mark temporary driver mem-resources
instead of global regions. This suppresses warnings if regions
overlap with a region marked as BUSY.
This was always the case for VESA/VGA/EFI framebuffer regions so
do the same for simplefb regions. The reason we do this is to
allow device handover to real GPU drivers like
i915/radeon/nouveau which get the same regions via PCI BARs.
Maybe at some point we will be able to unregister platform
devices properly during the handover. In this case the simplefb
region would get removed before the new region is created.
However, this is currently not the case and would require rather
huge changes in remove_conflicting_framebuffers(). Add the BUSY
marker now and try to eventually rewrite the handover for a next release.
Also see kernel/resource.c for more information:
/*
* if a resource is "BUSY", it's not a hardware resource
* but a driver mapping of such a resource; we don't want
* to warn for those; some drivers legitimately map only
* partial hardware resources. (example: vesafb)
*/
This suppresses warnings like:
------------[ cut here ]------------
WARNING: CPU: 2 PID: 199 at arch/x86/mm/ioremap.c:171 __ioremap_caller+0x2e3/0x390()
Info: mapping multiple BARs. Your kernel is fine.
Call Trace:
dump_stack+0x54/0x8d
warn_slowpath_common+0x7d/0xa0
warn_slowpath_fmt+0x4c/0x50
iomem_map_sanity_check+0xac/0xe0
__ioremap_caller+0x2e3/0x390
ioremap_wc+0x32/0x40
i915_driver_load+0x670/0xf50 [i915]
...
Reported-by: Tom Gundersen <teg@jklm.no>
Tested-by: Tom Gundersen <teg@jklm.no>
Tested-by: Pavel Roskin <proski@gnu.org>
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Link: http://lkml.kernel.org/r/1380724864-1757-1-git-send-email-dh.herrmann@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
On my MacBook Air lfb_size is 4M, which makes the bitshit
overflow (to 256GB - larger than 32 bits), meaning we fall
back to efifb unnecessarily.
Cast to u64 to avoid the overflow.
Signed-off-by: Tom Gundersen <teg@jklm.no>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Stephen Warren <swarren@nvidia.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Link: http://lkml.kernel.org/r/1380644320-1026-1-git-send-email-teg@jklm.no
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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>
David Herrmann