[PATCH] arm64: dts: add all hi6220 uart nodes

Tyler Baker tyler.baker at linaro.org
Tue Oct 6 07:29:18 PDT 2015


On 2 October 2015 at 11:00, Peter Griffin <peter.griffin at linaro.org> wrote:
> Hi Tyler,
>
> On Wed, 30 Sep 2015, Tyler Baker wrote:
>
>> On 30 September 2015 at 10:31, Mark Brown <broonie at kernel.org> wrote:
>> > On Wed, Sep 30, 2015 at 10:24:56AM +0200, Arnd Bergmann wrote:
>> >> On Tuesday 29 September 2015 13:29:12 Tyler Baker wrote:
>> >
>> >> >         aliases {
>> >> >                 serial0 = &uart0;
>> >> > +               serial1 = &uart1;
>> >> > +               serial2 = &uart2;
>> >> > +               serial3 = &uart3;
>> >> > +               serial4 = &uart4;
>> >> >         };
>> >
>> >> In the changelog you mention "both uarts", but here you have five of them.
>> >> Are they all accessible on the connector? If not, only provide aliases
>> >> for the ones that are, using numbering that makes most sense for given
>> >> how one would use the board.
>>
>> Thanks for the comment Arnd. Mark's comment below is correct, there
>> are only two UARTs accessible on the LS connection in addition to the
>> one on the board (solder pad).
>>
>> Is the following definition any clearer?
>>
>> serial0 = &uart0; // Onboard UART0
>> serial1 = &uart2; // LS expansion UART0
>> serial2 = &uart3; // LS expansion UART1
>>
>> If so, I'll respin this patch.
>>
>> > Unless I'm missing something there's only two UARTs brought out on the
>> > low speed expansion connector (in addition to the one on the solder pads
>> > which is currently supported).  We should also adjust the console
>> > default to match whatever one of the low speed expansion connector UARTs
>> > is being used by the bootloader.
>>
>> Your not missing anything, I should not have added the additional
>> aliases, it is confusing, will remove. The UART boards by default come
>> configured to use UART1 on the LS connector.
>>
>> + Peter as he has been submitting u-boot patches recently for the HiKey.
>
> Thanks :)
>
>>
>> Obviously, both UEFI and u-boot can be configured to use either UART,
>> and at the moment u-boot defaults to using the on board UART. Whereas
>> UEFI is using UART1 on the LS connector. I'm fine with switching the
>> console default to use the UART1 on the LS connector as long as there
>> is agreement to do so.
>
> Eek... "serial2 = uart3 //UART1"

Yeah, I fixed this in v2 :)

> I sent the following patch
> http://lists.denx.de/pipermail/u-boot/2015-September/227465.html
>
> which has been accepted which switches from using UART0 (onboard) to
> UART3 (LS connector). This matched up with the change made in ATF i.e. both ATF
> and u-boot were then both outputting on the same UART.
>
> So u-boot has already been migrated over.

Excellent!

Cheers,

Tyler



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