Re: [RFC v2 3/4] ACPI: DBG2: add 16550 UART with 32-bit access

From: Rafael J. Wysocki
Date: Tue Dec 06 2016 - 16:00:47 EST


On Tue, Dec 6, 2016 at 6:58 PM, Aleksey Makarov
<aleksey.makarov@xxxxxxxxxx> wrote:
> It was suggested to add a new Microsoft Debug Port Table 2
> (DBG2) (the table used to enumerate the various subtypes of serial
> port covered by the SPCR) 16550 UART subtype that may be needed for
> some additional platforms, such as those based upon AppliedMicro
> X-Gene ARMv8 SoCs. This new subtype would be 16550-compatible
> with 32-bit access. There already exists 32-bit variant
> ACPI_DBG2_ARM_SBSA_32BIT of SBSA console ACPI_DBG2_ARM_SBSA_GENERIC.
>
> This patch introduces it to Linux kernel.
>
> Signed-off-by: Aleksey Makarov <aleksey.makarov@xxxxxxxxxx>
> ---
> include/acpi/actbl2.h | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/include/acpi/actbl2.h b/include/acpi/actbl2.h
> index c93dbad..f219b04 100644
> --- a/include/acpi/actbl2.h
> +++ b/include/acpi/actbl2.h
> @@ -371,6 +371,7 @@ struct acpi_dbg2_device {
>
> #define ACPI_DBG2_16550_COMPATIBLE 0x0000
> #define ACPI_DBG2_16550_SUBSET 0x0001
> +#define ACPI_DBG2_16550_32BIT 0x0002
> #define ACPI_DBG2_ARM_PL011 0x0003
> #define ACPI_DBG2_ARM_SBSA_32BIT 0x000D
> #define ACPI_DBG2_ARM_SBSA_GENERIC 0x000E
> --

This is an ACPICA change and it first needs to be made to the upstream
ACPICA code base.

Thanks,
Rafael