Re: [PATCH 3/3] ACPI: SPCR: Add support for rev 3

[Rafael J. Wysocki]

On Fri, Oct 4, 2024 at 7:45 PM Raul Rangel <rrangel@xxxxxxxxxxxx> wrote:
>
> On Wed, Oct 2, 2024 at 12:13 PM Rafael J. Wysocki <rafael@xxxxxxxxxx> wrote:
> >
> > On Thu, Sep 12, 2024 at 7:39 PM Raul E Rangel <rrangel@xxxxxxxxxxxx> wrote:
> > >
> > > Revision 3 supports specifying the UART input clock. This allows for
> > > proper computation of the UART divisor when the baud rate is specified.
> > >
> > > The earlycon code can accept the following format (See `parse_options`
> > > in `earlycon.c`.):
> > > * <name>,io|mmio|mmio32|mmio32be,<addr>,<baud>,<uartclk>,<options>
> > >
> > > This change makes it so the uartclk is passed along if it's defined in
> > > the SPCR table.
> > >
> > > Booting with `earlycon` and a SPCR v3 table that has the uartclk and
> > > baud defined:
> > > [    0.028251] ACPI: SPCR: console: uart,mmio32,0xfedc9000,115200,48000000
> > > [    0.028267] earlycon: uart0 at MMIO32 0x00000000fedc9000 (options '115200,48000000')
> > > [    0.028272] printk: legacy bootconsole [uart0] enabled
> > >
> > > Link: https://learn.microsoft.com/en-us/windows-hardware/drivers/serports/serial-port-console-redirection-table
> > >
> > > Signed-off-by: Raul E Rangel <rrangel@xxxxxxxxxxxx>
> > >
> > > ---
> > >
> > >  drivers/acpi/spcr.c   | 5 ++++-
> > >  include/acpi/actbl3.h | 6 +++---
> > >  2 files changed, 7 insertions(+), 4 deletions(-)
> > >
> > > diff --git a/drivers/acpi/spcr.c b/drivers/acpi/spcr.c
> > > index cd36a97b0ea2c7..67ae42afcc59ef 100644
> > > --- a/drivers/acpi/spcr.c
> > > +++ b/drivers/acpi/spcr.c
> > > @@ -209,9 +209,12 @@ int __init acpi_parse_spcr(bool enable_earlycon, bool enable_console)
> > >         if (!baud_rate) {
> > >                 snprintf(opts, sizeof(opts), "%s,%s,0x%llx", uart, iotype,
> > >                          table->serial_port.address);
> > > -       } else {
> > > +       } else if (table->header.revision <= 2 || !table->uartclk) {
> > >                 snprintf(opts, sizeof(opts), "%s,%s,0x%llx,%d", uart, iotype,
> > >                          table->serial_port.address, baud_rate);
> > > +       } else {
> > > +               snprintf(opts, sizeof(opts), "%s,%s,0x%llx,%d,%d", uart, iotype,
> > > +                        table->serial_port.address, baud_rate, table->uartclk);
> > >         }
> > >
> > >         pr_info("console: %s\n", opts);
> > > diff --git a/include/acpi/actbl3.h b/include/acpi/actbl3.h
> > > index 8f775e3a08fdfb..afe45a2379866a 100644
> > > --- a/include/acpi/actbl3.h
> > > +++ b/include/acpi/actbl3.h
> >
> > The part of the patch below is outdated - SPCR v4 is supported already.
> >
> > Please rebase on the current mainline kernel source.
>
> Oh awesome. Should I send out all three patches again? Or just this
> one? I think patches 1 and 2 can be merged.

I have only received patch [3/3] and this one needs to be resent as
far as I'm concerned.