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

[Petr Mladek]

On Thu 2024-09-12 11:36:21, Raul E Rangel 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>

Looks good to me:

Reviewed-by: Petr Mladek <pmladek@xxxxxxxx>

Best Regards,
Petr