]> git.karo-electronics.de Git - linux-beck.git/commit
ARM: OMAP3: Use manual idle for UARTs because of DMA errata
authorTony Lindgren <tony@atomide.com>
Thu, 18 Sep 2014 15:58:49 +0000 (08:58 -0700)
committerTony Lindgren <tony@atomide.com>
Thu, 18 Sep 2014 15:58:49 +0000 (08:58 -0700)
commita2fc36613ac1af2e92cbed7af80bc72d8114dd50
tree765a989bea2447819f5d0bdb311538896a52d95f
parent6a08b11adda53b89d32d4becac4d7f062a0e2d99
ARM: OMAP3: Use manual idle for UARTs because of DMA errata

In sprz318f.pdf "Usage Note 2.7" says that UARTs cannot acknowledge
idle requests in smartidle mode when configured for DMA operations.
This prevents L4 from going idle. So let's use manual idle mode
instead.

Otherwise systems using Sebastian's 8250 patches with DMA will
never enter deeper idle states because of the errata above.

Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
arch/arm/mach-omap2/omap_hwmod_3xxx_data.c