Hi, Geert, On 19.02.2025 16:24, Geert Uytterhoeven wrote: > On (H)SCIF with a Baud Rate Generator for External Clock (BRG), there > are multiple ways to configure the requested serial speed. If firmware > uses a different method than Linux, and if any debug info is printed > after the Bit Rate Register (SCBRR) is restored, but before termios is > reconfigured (which configures the alternative method), the system may > lock-up during resume. > > Fix this by saving and restoring the contents of the Frequency Division > (DL) and Clock Select (CKS) registers as well. Keeping the thinks RZ/G3S focused (as proposed in the first versions of this support), I missed there might be other registers on other IP variants. Reviewing the full list of registers from [1], maybe the HSSRR and SCPCR should be saved/restored as well? Thank you, Claudiu [1] https://elixir.bootlin.com/linux/v6.13.3/source/drivers/tty/serial/sh-sci.h#L14 > > Fixes: 22a6984c5b5df8ea ("serial: sh-sci: Update the suspend/resume support") > Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx> For this patch: Tested-by: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx> Reviewed-by: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx> > --- > This can be reproduced on e.g. Salvator-X(S) by enabling the debug > print in sci_brg_calc(), and using s2ram with no_console_suspend. > --- > drivers/tty/serial/sh-sci.c | 10 ++++++++++ > 1 file changed, 10 insertions(+) > > diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c > index df6512c9c0ff28db..70f34b8a93888eb9 100644 > --- a/drivers/tty/serial/sh-sci.c > +++ b/drivers/tty/serial/sh-sci.c > @@ -109,6 +109,8 @@ struct sci_suspend_regs { > u16 scscr; > u16 scfcr; > u16 scsptr; > + u16 scdl; > + u16 sccks; > u8 scbrr; > u8 semr; > }; > @@ -3571,6 +3573,10 @@ static void sci_console_save(struct sci_port *s) > regs->scfcr = sci_serial_in(port, SCFCR); > if (sci_getreg(port, SCSPTR)->size) > regs->scsptr = sci_serial_in(port, SCSPTR); > + if (sci_getreg(port, SCDL)->size) > + regs->scdl = sci_serial_in(port, SCDL); > + if (sci_getreg(port, SCCKS)->size) > + regs->sccks = sci_serial_in(port, SCCKS); > if (sci_getreg(port, SCBRR)->size) > regs->scbrr = sci_serial_in(port, SCBRR); > if (sci_getreg(port, SEMR)->size) > @@ -3590,6 +3596,10 @@ static void sci_console_restore(struct sci_port *s) > sci_serial_out(port, SCFCR, regs->scfcr); > if (sci_getreg(port, SCSPTR)->size) > sci_serial_out(port, SCSPTR, regs->scsptr); > + if (sci_getreg(port, SCDL)->size) > + sci_serial_out(port, SCDL, regs->scdl); > + if (sci_getreg(port, SCCKS)->size) > + sci_serial_out(port, SCCKS, regs->sccks); > if (sci_getreg(port, SCBRR)->size) > sci_serial_out(port, SCBRR, regs->scbrr); > if (sci_getreg(port, SEMR)->size)
