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fbtft: Use contiguous memory for framebuffer. Add FBTFT_UPDATE IOCTL. #267

Open OtherCrashOverride opened 7 years ago

OtherCrashOverride commented 7 years ago

This patch changes the memory allocated for the LCD from paged to contiguous. This allows the memory to be used directly by the GE2D hardware blitter. A new FBTFT_UPDATE IOCTL is added to notify the driver that framebuffer contents have been changed. Without it, GE2D updates go unnoticed.

Additionally, the fix.smem_start variable is set to the physical address of the framebuffer. Previously, it always had a null value.

This patch can be tested with the following program branch that uses GE2D to blit directly to the LCD memory: https://github.com/OtherCrashOverride/c2screen2lcd/tree/fb