imx233: enable underflow recovery in lcdif (needed for freq scale)
commit0946a1e0f2c7c6491f87276cfadab5e9492313c6
authorAmaury Pouly <amaury.pouly@gmail.com>
Sat, 12 Jan 2013 18:58:19 +0000 (12 18:58 +0000)
committerAmaury Pouly <amaury.pouly@gmail.com>
Sat, 12 Jan 2013 18:58:19 +0000 (12 18:58 +0000)
tree42a6b389fd3e444c9a4544ecd13bff8da50cbb62
parent2ef7a549d57c984fee2cd26fbaa70bbfa054dfb4
imx233: enable underflow recovery in lcdif (needed for freq scale)

When chaging the cpu and memory frequency we need to disable the
external memory interface (EMI) for a small time. This can
underflow the dma and cause some breakage. Hopefully the SSP
controller handles this gracefully by stopping the clock and the
I2C probably handles this naturally because the clock can be
streched anyway. However the LCDIF has a special setting for this
which needs to be enable, otherwise it will send garbage to the
LCD. No other block is known to suffer from this currently but
this issue might have more unexpected consequences.

Change-Id: Ide154cad87929f2bf6cc419ac1d2ff33e30eec66
firmware/target/arm/imx233/creative-zenxfi2/lcd-zenxfi2.c
firmware/target/arm/imx233/creative-zenxfi3/lcd-zenxfi3.c
firmware/target/arm/imx233/lcdif-imx233.c
firmware/target/arm/imx233/lcdif-imx233.h
firmware/target/arm/imx233/sansa-fuzeplus/lcd-fuzeplus.c