[PATCH v5 40/46] boot: Support IO UARTs for earlycon and console

[Simon Glass]

Hi Tom,

On Thu, 3 Apr 2025 at 03:29, Tom Rini <trini at konsulko.com> wrote:
>
> On Sat, Mar 15, 2025 at 02:26:00PM +0000, Simon Glass wrote:
> > Update the string to take account of UARTs which are connected on I/O
> > ports, as on x86.
> >
> > Fix a typo in an error message in the same command, while we are here.
> >
> > Signed-off-by: Simon Glass <sjg at chromium.org>
> > ---
> >
> > (no changes since v3)
> >
> > Changes in v3:
> > - Add new patch to support IO UARTs for earlycon and console
> >
> >  boot/bootflow.c | 7 ++++---
> >  1 file changed, 4 insertions(+), 3 deletions(-)
> >
> > diff --git a/boot/bootflow.c b/boot/bootflow.c
> > index 58a1afa7a75..4054a966af8 100644
> > --- a/boot/bootflow.c
> > +++ b/boot/bootflow.c
> > @@ -942,8 +942,9 @@ int bootflow_cmdline_auto(struct bootflow *bflow, const char *arg)
> >       *buf = '\0';
> >       if (!strcmp("earlycon", arg) && info.type == SERIAL_CHIP_16550_COMPATIBLE) {
> >               snprintf(buf, sizeof(buf),
> > -                      "uart8250,mmio32,%#lx,%dn8", info.addr,
> > -                      info.baudrate);
> > +                      "uart8250,%s,%#lx,%dn8",
> > +                      info.addr_space == SERIAL_ADDRESS_SPACE_IO ? "io" :
> > +                      "mmio", info.addr, info.baudrate);
> >       } else if (!strcmp("earlycon", arg) && info.type == SERIAL_CHIP_PL01X) {
> >               snprintf(buf, sizeof(buf),
> >                        "pl011,mmio32,%#lx,%dn8", info.addr,
>
> I suppose we're well past the point where we can delete
> bootflow_cmdline_auto() itself because that's just going to lead us to
> trouble down the line (5 years from now when the kernel adopts a new
> preferred way to pass this info) and grows every platform by some amount
> of space every time we add something new here.

Well firstly, why would you want to delete this command? It is very
useful to be able to change the cmdline.

This command is only available with BOOTSTD_FULL, which is less than
10% of boards.

Regards,
Simon