More aggressive DMA mapping debugging has uncovered a long-standing
buglet in the way that the sh_mobile_lcdcfb driver implements its
deferred I/O callback. When used as a console driver the acceleration
routines are called by the kernel which subsequently cause the deferred
I/O work to be scheduled, resulting in the deferred I/O callback being
entered without any dirty pages on the pagelist (the normal case for
userspace accesses). It's also possible to get in to this situation via
explicit calling of fsync() when nothing has dirtied the region.
Unfortunately it's not sufficient to skip over the callback when the
pagelist is empty given the console driver use case, so instead the
callback has to conditionalize the work for panel updates and DMA
mapping depending on whether anything is resident on the pagelist or
not.
Reported-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Switch to using both register sets - side A and side B for display panning.
Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com>
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch modifies the SuperH Mobile LCDC framebuffer driver
to support Runtime PM. The driver is using the functions
- pm_runtime_get_sync()
- pm_runtime_put_sync()
to inform the bus code if the hardware is idle or not. If the
hardware is idle then the bus code may call the runtime dev_pm_ops
callbacks to save and restore state. pm_runtime_resume() is used
to allow the driver to access the hardware from probe().
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch updates the SuperH Mobile LCDC driver to skip
over disabled channels. Without this patch suspend-to-ram
operation will crash if deferred io is enabled.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Fix the SuperH Mobile LCDC driver to make use of the full
18-bit DRD field in the LDDRDR register. Without this patch
only 16-bit register access is possible. Needed by 18-bit
SYS panels such as the one used on kfr2r09.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Update the SuperH Mobile LCDC driver to wait for SYS bus to
become idle after reading or writing. This is needed by the
kfr2r09 board, but also fixes potential problems on other
boards making use of the LCDC in a SYS configuration.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
All fb_info structures need to be allocated with framebuffer_alloc() due
to special initialization. Switch over to it.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This deifdefs the driver and adds an explicit HAVE_CLK dependency. Given
that all SH platforms provide it, there is no reason to keep this as an
ifdef. Other architectures that implement support for this driver will
already have to provide clock framework support for timers and so on
already, so adding this as an additional dependency is not terribly
probematic.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Since writenotify on uncached vmas is unsupported in 2.6.31,
live with cached framebuffer memory in the deferred io
case for now and flush the dcache before forcing refresh.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: Magnus damm <damm@igel.co.jp>
This patch fixes the LCDC driver to avoid calling the
function sh_mobile_lcdc_start_stop(priv, 0) unless the
same function has been called before to start the LCDC
hardware.
Triggered when sh_mobile_lcdcfb.c failed to probe() due to
missing MSTP clocks.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch adds suspend/resume support to the LCDC
driver for SuperH Mobile - sh_mobile_lcdcfb.
We simply stop hardware on suspend and start it again
on resume. For RGB panels this is trivial, but for SYS
panels in deferred io mode this becomes a bit more
difficult - we need to wait for a frame end interrupt
to make sure the clocks are balanced before stopping
the actual hardware.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Fix deferred io cleanup patch in the sh_mobile_lcdcfb driver.
If probe() fails early the sh_mobile_lcdc_stop() function will
be called to clean up deferred io. This patch modifies the
code to only call fb_deferred_io_cleanup() after deferred io
has been initialized.
With this patch applied we no longer hit BUG_ON() inside
fb_deferred_io_cleanup(). Triggers on a Migo-R with the
SYS QVGA panel board unmounted.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch adds sh_mobile_lcdcfb deferred io support for SYS panels.
The LCDC hardware block managed by the sh_mobile_lcdcfb driver supports
RGB or SYS panel configurations. SYS panels come with an external display
controller that is resposible for refreshing the actual LCD panel. RGB
panels are controlled directly by the LCDC and they need to be refreshed
by the LCDC hardware.
In the case of SYS panels we can save some power by configuring the LCDC
hardware block in one-shot mode. In this one-shot mode panel refresh is
managed by software. This works well together with deferred io since it
allows us to stop clocks for most of the time and only enable clocks when
we actually want to trigger an update. When there is no fbdev activity
the clocks are kept stopped which allows us to deep sleep.
The refresh rate in deferred io mode is set using platform data. The same
platform data can also be used to disable deferred io mode.
As with other deferred io frame buffers user space code should use fsync()
on the frame buffer device to trigger an update.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Since the sh_mobile_lcdc hardware has the framebuffer(s) in system RAM,
use FB_SYS instead of FB_CFB. Also hook in read and write helpers.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Add clock framework support to the lcdc driver and
adjust the board specific code accordingly.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Add platform data flags for detailed lcd display configuration.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Remove lddckr from the platform data, these days we calculate the
register value from clock source and clock dividers anyway.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This provides a workaround for users of sh_mobile_lcdcfb that don't
define HAVE_CLK and have otherwise sane clock initialization.
At the same time, move the sh_mobile_lcdc.h header to include/video/.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Export the LCD panel size for sh_mobile_lcdc boards. This allows us
to perform dpi and screen aspect ratio calculations in user space.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This is the SuperH Mobile LCDC frame buffer driver V2, adding support for
the LCDC block found in SuperH Mobile processors. The hardware supports
up to two LCD panels per LCDC block, and both RGB and SYS interfaces can
be used to hook up LCD panels/modules.
The device driver is a regular platform driver, so LCD configuration and
board specific hooks are passed to the driver using platform data. LCD
modules using SYS interface often require special configuration using the
SYS bus, and to solve this cleanly the driver provides SYS interface
operations to the board code.
Tested on sh7723 and sh7722 processors with a SYS16A QVGA panel and WVGA
panels using RGB16 and RGB18 interfaces.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Reviewed-by: Krzysztof Helt <krzysztof.h1@poczta.fm>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
