diff options
| author | Nicolas Boichat <drinkcat@chromium.org> | 2018-08-27 16:05:09 +0800 |
|---|---|---|
| committer | chrome-bot <chrome-bot@chromium.org> | 2018-08-29 11:15:45 -0700 |
| commit | 7eb9ff3cfcf4b96356050da66bd957225bef6044 (patch) | |
| tree | 62b5f35d135e99fa14e582d3487fabb6fa41aab2 /chip/stm32/usart.c | |
| parent | 63fd7e18588023b2940167b686611e609354b78a (diff) | |
| download | chrome-ec-7eb9ff3cfcf4b96356050da66bd957225bef6044.tar.gz | |
servo_micro: Allow setting the baud rate for usart
We set the baud rate in increments of 100 baud, to avoid
overflowing the 16-bit wValue integer (921600 is the highest we
are likely to use).
Also, increment the buffer size for USART3 to 1024 bytes. That
helps a bit to avoid losing characters, but we still can't keep
up if the host is printing at maximum speed.
BRANCH=servo
BUG=chromium:876651
TEST=baud usart2/3/4 115200 in servo_micro console
TEST=dut-control cpu_uart_baudrate:921600
seq 1 1000 shows numbers 1 to 226 before buffer overflows
Change-Id: Ifca266189f93def493f207dd29d2cceca4d8d68f
Signed-off-by: Nicolas Boichat <drinkcat@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/1189782
Reviewed-by: Nick Sanders <nsanders@chromium.org>
Diffstat (limited to 'chip/stm32/usart.c')
| -rw-r--r-- | chip/stm32/usart.c | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/chip/stm32/usart.c b/chip/stm32/usart.c index 90be4f6194..0ef357466c 100644 --- a/chip/stm32/usart.c +++ b/chip/stm32/usart.c @@ -86,9 +86,10 @@ void usart_shutdown(struct usart_config const *config) config->hw->ops->disable(config); } -void usart_set_baud_f0_l(struct usart_config const *config, int frequency_hz) +void usart_set_baud_f0_l(struct usart_config const *config, int baud, + int frequency_hz) { - int div = DIV_ROUND_NEAREST(frequency_hz, config->baud); + int div = DIV_ROUND_NEAREST(frequency_hz, baud); intptr_t base = config->hw->base; if (div / 16 > 0) { @@ -108,9 +109,10 @@ void usart_set_baud_f0_l(struct usart_config const *config, int frequency_hz) } } -void usart_set_baud_f(struct usart_config const *config, int frequency_hz) +void usart_set_baud_f(struct usart_config const *config, int baud, + int frequency_hz) { - int div = DIV_ROUND_NEAREST(frequency_hz, config->baud); + int div = DIV_ROUND_NEAREST(frequency_hz, baud); /* STM32F only supports x16 oversampling */ STM32_USART_BRR(config->hw->base) = div; |