Commit graph

7 commits

Author SHA1 Message Date
David Herrmann
9e210be68a simplefb: use write-combined remapping
Framebuffers shouldn't be cached and it is usually very uncommon to read
them. Therefore, use ioremap_wc() to get significant speed improvements on
systems which provide it. On all other systems it's aliased to
ioremap_nocache() which is also fine.

Reported-by: Tom Gundersen <teg@jklm.no>
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Tested-by: Tom Gundersen <teg@jklm.no>
Tested-by: Alexandre Courbot <acourbot@nvidia.com>
Tested-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2013-10-30 12:49:02 +02:00
David Herrmann
498f6d3660 simplefb: fix unmapping fb during destruction
Unfortunately, fbdev does not create its own "struct device" for
framebuffers. Instead, it attaches to the device of the parent layer. This
has the side-effect that devm_* managed resources are not cleaned up on
framebuffer-destruction but rather during destruction of the
parent-device. In case of fbdev this might be too late, though.
remove_conflicting_framebuffer() may remove fbdev devices but keep the
parent device as it is.

Therefore, we now use plain ioremap() and unmap the framebuffer in the
fb_destroy() callback. Note that we must not free the device here as this
might race with the parent-device removal. Instead, we rely on
unregister_framebuffer() as barrier and we're safe.

Reported-by: Tom Gundersen <teg@jklm.no>
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Acked-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2013-10-30 12:49:01 +02:00
Tom Gundersen
9f192a9228 simplefb: print some info about the registered fb
This is similar to the output printed by efifb.

Signed-off-by: Tom Gundersen <teg@jklm.no>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Cc: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2013-10-09 12:35:46 +03:00
Jingoo Han
129f1be4b9 video: simplefb: use dev_get_platdata()
Use the wrapper function for retrieving the platform data instead of
accessing dev->platform_data directly. This is a cosmetic change
to make the code simpler and enhance the readability.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2013-09-20 12:23:21 +03:00
David Herrmann
df0960ab2d fbdev: simplefb: mark as fw and allocate apertures
fbdev-core uses FBINFO_MISC_FIRMWARE to mark drivers that use firmware
framebuffers. Furthermore, we now allocate apertures for the fbinfo
device.
Both information is used by remove_conflicting_framebuffers() to remove a
fbdev device whenever a real driver is loaded. This is used heavily on x86
for VGA/vesa/EFI framebuffers, but is also of great use for all other
systems.

Especially with x86 support for simplefb, this information is needed to
unload simplefb before a real hw-driver (like i915, radeon, nouveau) is
loaded.

Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Link: http://lkml.kernel.org/r/1375445127-15480-3-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 16:17:45 -07:00
David Herrmann
5ef76da644 fbdev: simplefb: add init through platform_data
If we create proper platform-devices in x86 boot-code, we can use simplefb
for VBE or EFI framebuffers, too. However, there is normally no OF support
so we introduce a platform_data object so x86 boot-code can pass the
parameters via plain old platform-data.

This also removes the OF dependency as it is not needed. The headers
provide proper dummies for the case OF is disabled.

Furthermore, we move the FORMAT-definitions to the common platform header
so initialization code can use it to transform "struct screen_info" to
the right format-name.

Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Link: http://lkml.kernel.org/r/1375445127-15480-2-git-send-email-dh.herrmann@gmail.com
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-08-02 16:17:44 -07:00
Stephen Warren
26549c8d36 drivers/video: implement a simple framebuffer driver
A simple frame-buffer describes a raw memory region that may be rendered
to, with the assumption that the display hardware has already been set
up to scan out from that buffer.

This is useful in cases where a bootloader exists and has set up the
display hardware, but a Linux driver doesn't yet exist for the display
hardware.

Examples use-cases include:

* The built-in LCD panels on the Samsung ARM chromebook, and Tegra
  devices, and likely many other ARM or embedded systems.  These cannot
  yet be supported using a full graphics driver, since the panel control
  should be provided by the CDF (Common Display Framework), which has been
  stuck in design/review for quite some time.  One could support these
  panels using custom SoC-specific code, but there is a desire to use
  common infra-structure rather than having each SoC vendor invent their
  own code, hence the desire to wait for CDF.

* Hardware for which a full graphics driver is not yet available, and
  the path to obtain one upstream isn't yet clear.  For example, the
  Raspberry Pi.

* Any hardware in early stages of upstreaming, before a full graphics
  driver has been tackled.  This driver can provide a graphical boot
  console (even full X support) much earlier in the upstreaming process,
  thus making new SoC or board support more generally useful earlier.

[akpm@linux-foundation.org: make simplefb_formats[] static]
Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: Olof Johansson <olof@lixom.net>
Cc: Rob Clark <robclark@gmail.com>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Cc: Tomasz Figa <tomasz.figa@gmail.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-24 16:22:51 -07:00