Re: [PATCH v2] tty: amba-pl011: Use 32-bit accesses for SBSA UART

From: Christopher Covington
Date: Fri Mar 11 2016 - 18:38:57 EST




On March 11, 2016 10:02:14 PM GMT+07:00, Peter Hurley <peter@xxxxxxxxxxxxxxxxxx> wrote:
>Hi Christopher,
>
>On 03/10/2016 10:35 PM, Christopher Covington wrote:
>> Version 2 of the Server Base System Architecture (SBSAv2) describes
>the
>> Generic UART registers as 32 bits wide. At least one implementation,
>found
>> on the Qualcomm Technologies QDF2432, only supports 32 bit accesses.
>> SBSAv3, which describes supported access sizes in greater detail,
>> explicitly requires support for both 16 and 32 bit accesses to all
>> registers (and 8 bit accesses to some but not all). Therefore, for
>broad
>> compatibility, simply use 32 bit accessors for the SBSA UART.
>
>So this eliminates the need to configure SBSA port via ACPI, correct?
>Thus, Aleksey can drop his "serial: pl011: use SPCR to setup 32-bit
>access"?

Yes.

Thanks,
Christopher Covington

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