OMAPFB: use dma_alloc instead of omap's vram

Quoted 23 lines · Tomi Valkeinen

Hi,

This series changes omapfb to use standard dma_alloc funcs instead of omap specific vram allocator. This let's us remove the omap vram allocator, making omapfb platform independent.

However, note that using standard dma funcs causes the following downsides:

1) dma_alloc_attrs doesn't let us allocate at certain physical address. However, this should not be a problem as this feature of vram allocator is only used when reserving the framebuffer that was initialized by the bootloader, and we don't currently support "passing" a framebuffer from the bootloader to the kernel anyway.

2) dma_alloc_attrs, as of now, always ioremaps the allocated area, and we don't need the ioremap when using VRFB. This patch uses DMA_ATTR_NO_KERNEL_MAPPING for the allocation, but the flag is currently not operational.

3) OMAPFB_GET_VRAM_INFO ioctl cannot return real values anymore. I changed the ioctl to return 64M for all the values, which, I hope, the applications will interpret as "there's enough vram".

Quoted 2 lines

4) "vram" kernel parameter to define how much ram to reserve for video use no longer works. The user needs to enable CMA and use "cma" parameter.

Great, thanks for fixing these. Could you please queue these into a separate branch against v3.7-rc5 that I can also merge into omap-for-v3.8/cleanup-headers-prepare-multiplatform-v3?