Randall Spangler af12f2f58c stm32: Support DMA-based UART output ...

This reduces the number of UART interrupts by a factor of 12, and
reduces the overall interrupt rate on STM32 by a factor of 2.

BUG=chrome-os-partner:20485
BRANCH=none (not required for pit branch)
TEST=Boot pit.  Ctrl+Q pauses debug output; Ctrl+S resumes it.
     'crash divzero' still prints a full crash dump.
     And util/makeall.sh passes builds all platforms and passes tests.

Change-Id: I86993e14b436150298dcb2c6d29086cc3c9db418
Signed-off-by: Randall Spangler <rspangler@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/168814

2013-09-11 22:41:22 +00:00

..

host

Split uart_process() into input and output processing

2013-09-11 19:46:10 +00:00

lm4

Split uart_process() into input and output processing

2013-09-11 19:46:10 +00:00

stm32

stm32: Support DMA-based UART output

2013-09-11 22:41:22 +00:00