export access to the 'Local Shared OS and T_Crit Limit'
register.

Hack to avoid 24 Hz mode in X resulting in no display at all. This has
been encountered using e.g. a Samsung SyncMaster F2380 if connected by
HDMI.

root@apalis-t30:~# xrandr
Screen 0: minimum 256 x 128, current 1920 x 1080, maximum 2048 x 2048
LVDS-1 connected 1920x1080+0+0 (normal left inverted right x axis y axis) 0mm x 0mm
   1920x1080      58.6*+
HDMI-1 connected 1920x1080+0+0 (normal left inverted right x axis y axis) 160mm x 90mm
   1920x1080      60.0 +   24.0*
   1680x1050      59.9
   1280x1024      75.0     60.0
   1440x900       75.0     59.9
   1280x960       60.0
   1280x800       59.9
   1152x864       75.0
   1280x720       60.0     50.0
   1024x768       75.0     70.1     60.0
   832x624        74.6
   800x600        72.2     75.0     60.3     56.2
   720x576        50.0
   720x480        59.9
   640x480        75.0     72.8     66.7     59.9
   720x400        70.1

Previously only 64-lead and 40-lead models were identified. This patch
adds 48-lead and 32-lead device identification as well.

Please note that due to missing parameter negotiation functions one
might get the following message with a subsequent crash:

WARNING: from element /GstPipeline:pipeline0/GstV4l2Src:v4l2src0: Could
not get parameters on device '/dev/video0'

This can be avoided by explicitly specifying the format as follows:

gst-launch v4l2src ! deinterlace tff=1 method=4 ! 'video/x-raw-yuv,
width=(int)720, height=(int)576, format=(fourcc)I420' !
nv_omx_videomixer ! nv_gl_eglimagesink

Powering on, improved interlacing.

Move paddr to correct ifdef to enable CONFIG_NVMAP_PAGE_POOLS=n
compilation.

Use right buffer flag NVMAP_HANDLE_WRITE_COMBINE to allocate buffer,
which can be shared by VI/CSI and CPU. Don't use NVMAP_HEAP_SYSMEM.
It is validated to old T20 silicon and can't support big buffers. By
default, our nvmap_alloc() will use IOVMM to allocate buffers.

nvmap_pin() gives us IOVA for hardware engines like VI/CSI module
with IOMMU enabled in kernel. nvmap_mmap() gives us VA for CPU
read/write operations. So we need to convert VA address to physical
address of the buffer and map that buffer to user space processor's
memory space "page by page".

Change-Id: I543d9d95fc14395200647e09480f25d9bc001e00
Signed-off-by: Bryan Wu <pengw@nvidia.com>