Hi Chris,
On Tue, Aug 7, 2018 at 9:24 PM Chris Brandt <Chris.Brandt@xxxxxxxxxxx> wrote:
> On Monday, August 06, 2018 1, Geert Uytterhoeven wrote:
> > > I had a simple patch to add support for CONFIG_DEBUG_LL for RZ/A2
> > > because earlycon never worked because of RZ/A2's different register
> > locations.
> >
> > Yeah, sci_probe_regmap() assumed the wrong regtype for your TYPE_SCIF
> > port. You needed an OF_EARLYCON_DECLARE() line that also filled in
> > the correct regtype.
>
>
> I gave your patch a try.
> When earlycon is enabled, on RZ/A2, it gets stuck in here:
>
> static void sci_poll_put_char(struct uart_port *port, unsigned char c)
> {
> unsigned short status;
>
> do {
> status = serial_port_in(port, SCxSR);
> } while (!(status & SCxSR_TDxE(port)));
>
> serial_port_out(port, SCxTDR, c);
> sci_clear_SCxSR(port, SCxSR_TDxE_CLEAR(port) & ~SCxSR_TEND(port));
> }
>
>
> I see that you added this:
>
> OF_EARLYCON_DECLARE(scif, "renesas,scif-r7s9210", rza2_early_console_setup);
>
> and "renesas,scif-r7s9210" matches what I have in my .dtsi.
>
> But, when I run the code, I end up in function scif_early_console_setup,
> not rza2_early_console_setup
Hmm, perhaps it doesn't pick the first/most specialized match.
> I'm assuming I'm just supposed to use this on my bootargs:
> earlycon=scif,0xE8009000
Just "earlycon" should be sufficient. It'll find the right port from
chosen/stdout-path
in DT. Can you please retry using that?
Thanks!
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
