On Tuesday 10 January 2023 20:24:07 Loic Poulain wrote:
> Instead of waiting for empty FIFO condition before writing a
> character, wait for non-full FIFO condition.
>
> This helps in saving several tens of milliseconds during boot
> (depending verbosity).
>
> Signed-off-by: Loic Poulain <loic.poul...@linaro.org>
> Tested-by: Lothar Waßmann <l...@karo-electronics.de>
> ---
> v2: fixing transfert abort & char corruption commit
> v3: Reordering commits for good bisectability
>
> drivers/serial/serial_mxc.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/serial/serial_mxc.c b/drivers/serial/serial_mxc.c
> index 3c89781f2c..9899155c00 100644
> --- a/drivers/serial/serial_mxc.c
> +++ b/drivers/serial/serial_mxc.c
> @@ -238,11 +238,11 @@ static void mxc_serial_putc(const char c)
> if (c == '\n')
> serial_putc('\r');
>
> - writel(c, &mxc_base->txd);
> -
> /* wait for transmitter to be ready */
> - while (!(readl(&mxc_base->ts) & UTS_TXEMPTY))
> + while (readl(&mxc_base->ts) & UTS_TXFULL)
> schedule();
> +
> + writel(c, &mxc_base->txd);
> }
>
> /* Test whether a character is in the RX buffer */
> @@ -333,7 +333,7 @@ static int mxc_serial_putc(struct udevice *dev, const
> char ch)
> struct mxc_serial_plat *plat = dev_get_plat(dev);
> struct mxc_uart *const uart = plat->reg;
>
> - if (!(readl(&uart->ts) & UTS_TXEMPTY))
> + if (readl(&uart->ts) & UTS_TXFULL)
> return -EAGAIN;
>
> writel(ch, &uart->txd);
> --
> 2.34.1
>
Hello!
In this driver there are two mxc_serial_putc() and two mxc_serial_getc()
function. One for DM and one for non-DM version. It would be really nice
to fix also second set of functions.
