Hi Sean,
Am Do., 17. März 2022 um 15:38 Uhr schrieb Sean Anderson <sean...@gmail.com>:
>
> Hi Heiko,
>
> On 3/17/22 8:41 AM, Heiko Thiery wrote:
> > With the clock driver enabled for the imx8mq, it was noticed that the
> > frequency used to calculate the baud rate is always taken from the root
> > clock of UART1. This can cause problems if UART1 is not used as console
> > and the settings are different from UART1. The result is that the console
> > output is garbage. To do this correctly the UART frequency is taken from
> > the used device. For the implementations that don't have the igp clock
> > frequency written or can't return it the old way is tried.
> >
> > Signed-off-by: Heiko Thiery <heiko.thi...@gmail.com>
> > ---
> > drivers/serial/serial_mxc.c | 15 +++++++++++++--
> > 1 file changed, 13 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/serial/serial_mxc.c b/drivers/serial/serial_mxc.c
> > index e4970a169b..6fdb2b2397 100644
> > --- a/drivers/serial/serial_mxc.c
> > +++ b/drivers/serial/serial_mxc.c
> > @@ -3,6 +3,7 @@
> > * (c) 2007 Sascha Hauer <s.ha...@pengutronix.de>
> > */
> >
> > +#include <clk.h>
> > #include <common.h>
> > #include <dm.h>
> > #include <errno.h>
> > @@ -266,9 +267,19 @@ __weak struct serial_device
> > *default_serial_console(void)
> > int mxc_serial_setbrg(struct udevice *dev, int baudrate)
> > {
> > struct mxc_serial_plat *plat = dev_get_plat(dev);
> > - u32 clk = imx_get_uartclk();
> > + u32 rate = 0;
> > +
> > + if (IS_ENABLED(CONFIG_CLK)) {
>
> CONFIG_IS_ENABLED?
This should be correct. The CONFIG_IS_ENABLED is a preprocessor macro
and the IS_ENABLED can be used in c code. Or do you mean something
else?
>
> mx6ull at least does not have CONFIG_SPL_CLK enabled.
I expect that in that case it will fallback to the old behavior ... not?
>
> > + struct clk clk;
> > + if(!clk_get_by_name(dev, "ipg", &clk))
> > + rate = clk_get_rate(&clk);
> > + }
> > +
> > + /* as fallback we try to get the clk rate that way */
> > + if (rate == 0)
>
> !rate || IS_ERR_VALUE(rate)
>
> > + rate = imx_get_uartclk();
> >
> > - _mxc_serial_setbrg(plat->reg, clk, baudrate, plat->use_dte);
> > + _mxc_serial_setbrg(plat->reg, rate, baudrate, plat->use_dte);
> >
> > return 0;
> > }
> >
> --Sean
--
Heiko
