bcm2708 framebuffer driver

Signed-off-by: popcornmix <popcornmix@gmail.com>

bcm2708_fb : Implement blanking support using the mailbox property interface

bcm2708_fb: Add pan and vsync controls

bcm2708_fb: DMA acceleration for fb_copyarea

Based on http://www.raspberrypi.org/phpBB3/viewtopic.php?p=62425#p62425


Also used Simon's dmaer_master module as a reference for tweaking DMA
settings for better performance.

For now busylooping only. IRQ support might be added later.
With non-overclocked Raspberry Pi, the performance is ~360 MB/s
for simple copy or ~260 MB/s for two-pass copy (used when dragging
windows to the right).

In the case of using DMA channel 0, the performance improves
to ~440 MB/s.

For comparison, VFP optimized CPU copy can only do ~114 MB/s in
the same conditions (hindered by reading uncached source buffer).

Signed-off-by: Siarhei Siamashka <siarhei.siamashka@gmail.com>

bcm2708_fb: report number of dma copies

Add a counter (exported via debugfs) reporting the
number of dma copies that the framebuffer driver
has done, in order to help evaluate different
optimization strategies.

Signed-off-by: Luke Diamand <luked@broadcom.com>

bcm2708_fb: use IRQ for DMA copies

The copyarea ioctl() uses DMA to speed things along. This
was busy-waiting for completion. This change supports using
an interrupt instead for larger transfers. For small
transfers, busy-waiting is still likely to be faster.

Signed-off-by: Luke Diamand <luke@diamand.org>

bcm2708: Make ioctl logging quieter

video: fbdev: bcm2708_fb: Don't panic on error

No need to panic the kernel if the video driver fails.
Just print a message and return an error.

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>

fbdev: bcm2708_fb: Add ARCH_BCM2835 support

Add Device Tree support.
Pass the device to dma_alloc_coherent() in order to get the
correct bus address on ARCH_BCM2835.
Use the new DMA legacy API header file.
Including <mach/platform.h> is not necessary.

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>

BCM270x_DT: Add bcm2708-fb device

Add bcm2708-fb to Device Tree and don't add the
platform device when booting in DT mode.

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>

Cleanup of bcm2708_fb file to kernel coding standards

Some minor change to function - remove a use of
in_atomic, plus replacing various debug messages
that manually specify the function name with
("%s",.__func__)

Signed-off-by: James Hughes <james.hughes@raspberrypi.org>

video: bcm2708_fb: Try allocating on the ARM and passing to VPU

Currently the VPU allocates the contiguous buffer for the
framebuffer.
Try an alternate path first where we use dma_alloc_coherent
and pass the buffer to the VPU. Should the VPU firmware not
support that path, then free the buffer and revert to the
old behaviour of using the VPU allocation.

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.org>