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linux-stable-rt/Documentation/fb/pxafb.txt

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Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
Driver for PXA25x LCD controller
================================
The driver supports the following options, either via
options=<OPTIONS> when modular or video=pxafb:<OPTIONS> when built in.
For example:
[ARM] pxafb: allow video memory size to be configurable The amount of video memory size is decided according to the following order: 1. <xres> x <yres> x <bits_per_pixel> by default, which is the backward compatible way 2. size specified in platform data 3. size specified in module parameter 'options' string or specified in kernel boot command line (see updated Documentation/fb/pxafb.txt) And now since the memory is allocated from system memory, the pxafb_mmap can be removed and the default fb_mmap() should be working all right. Also, since we now have introduced the 'struct pxafb_dma_buff' for DMA descriptors and palettes, the allocation can be separated cleanly. NOTE: the LCD DMA actually supports chained transfer (i.e. page-based transfers), to simplify the logic and keep the performance (with less TLB misses when accessing from memory mapped user space), the memory is allocated by alloc_pages_*() to ensures it's physical contiguous. Signed-off-by: Eric Miao <eric.miao@marvell.com> Signed-off-by: Eric Miao <ycmiao@ycmiao-hp520.(none)>
2008-12-16 11:54:34 +08:00
modprobe pxafb options=vmem:2M,mode:640x480-8,passive
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
or on the kernel command line
[ARM] pxafb: allow video memory size to be configurable The amount of video memory size is decided according to the following order: 1. <xres> x <yres> x <bits_per_pixel> by default, which is the backward compatible way 2. size specified in platform data 3. size specified in module parameter 'options' string or specified in kernel boot command line (see updated Documentation/fb/pxafb.txt) And now since the memory is allocated from system memory, the pxafb_mmap can be removed and the default fb_mmap() should be working all right. Also, since we now have introduced the 'struct pxafb_dma_buff' for DMA descriptors and palettes, the allocation can be separated cleanly. NOTE: the LCD DMA actually supports chained transfer (i.e. page-based transfers), to simplify the logic and keep the performance (with less TLB misses when accessing from memory mapped user space), the memory is allocated by alloc_pages_*() to ensures it's physical contiguous. Signed-off-by: Eric Miao <eric.miao@marvell.com> Signed-off-by: Eric Miao <ycmiao@ycmiao-hp520.(none)>
2008-12-16 11:54:34 +08:00
video=pxafb:vmem:2M,mode:640x480-8,passive
vmem: VIDEO_MEM_SIZE
Amount of video memory to allocate (can be suffixed with K or M
for kilobytes or megabytes)
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-17 06:20:36 +08:00
mode:XRESxYRES[-BPP]
XRES == LCCR1_PPL + 1
YRES == LLCR2_LPP + 1
The resolution of the display in pixels
BPP == The bit depth. Valid values are 1, 2, 4, 8 and 16.
pixclock:PIXCLOCK
Pixel clock in picoseconds
left:LEFT == LCCR1_BLW + 1
right:RIGHT == LCCR1_ELW + 1
hsynclen:HSYNC == LCCR1_HSW + 1
upper:UPPER == LCCR2_BFW
lower:LOWER == LCCR2_EFR
vsynclen:VSYNC == LCCR2_VSW + 1
Display margins and sync times
color | mono => LCCR0_CMS
umm...
active | passive => LCCR0_PAS
Active (TFT) or Passive (STN) display
single | dual => LCCR0_SDS
Single or dual panel passive display
4pix | 8pix => LCCR0_DPD
4 or 8 pixel monochrome single panel data
hsync:HSYNC
vsync:VSYNC
Horizontal and vertical sync. 0 => active low, 1 => active
high.
dpc:DPC
Double pixel clock. 1=>true, 0=>false
outputen:POLARITY
Output Enable Polarity. 0 => active low, 1 => active high
pixclockpol:POLARITY
pixel clock polarity
0 => falling edge, 1 => rising edge