Re: [PATCH v2 06/10] soc: fsl: qe: Add support for QMC

From: Christophe Leroy
Date: Wed Jan 11 2023 - 12:39:16 EST




Le 11/01/2023 à 16:40, Herve Codina a écrit :
> Hi Christophe,
> On Wed, 11 Jan 2023 13:58:03 +0000
> Christophe Leroy <christophe.leroy@xxxxxxxxxx> wrote:
>
>> Le 06/01/2023 à 17:37, Herve Codina a écrit :
>>> The QMC (QUICC Multichannel Controller) is available on some
>>> PowerQUICC SoC such as the MPC885 or MPC866.
>>
>> Same, that's QMC for CPM for the time being, should that be made clear
>> in the subject ?
>
> Also same answer:
> Will changing the subject be enough or do I need to move it to new
> created drivers/soc/fsl/cpm/ directory ?
>
>>
>> QE also has QMC and this driver might be used for QE QMC as well with
>> some enhancement, maybe that could be explained here ?
>
> Yes and we plan to have it working on QE too.
>
> What do you think if I add the following:
> The QMC is also available on some Quicc Engine SoC.
> This current version support CPM1 SoC only. Some
> enhancement are needed to support Quicc Engine SoC.
>

That's look good.

>>
>> I see you are using in_be16(), out_be16() etc ....
>> That's specific to powerpc arch, maybe it is better to use ioread16be,
>> iowrite16be() etc ....
>> See commit 3f39f38ea91d ("soc: fsl: qe: replace qe_io{read,write}*
>> wrappers by generic io{read,write}*") and commit 6ac9b61786cc ("soc:
>> fsl: qe: introduce qe_io{read,write}* wrappers") for information.
>
> You're right.
> I will switch to io{read,write}{16,32}be.
>
> I prefer avoid the use of qe_* wrappers as the driver is not
> (yet) compatible with QE.

By the way that was the purpose of commit 3f39f38ea91d ("soc: fsl: qe:
replace qe_io{read,write}* wrappers by generic io{read,write}*"),
replace qe_* wrappers by direct use of io{read,write}{16,32}be

So yes, using io{read,write}{16,32}be directly is preferable.

>
>>
>>>
>>> It emulates up to 64 channels within one serial controller
>>> using the same TDM physical interface routed from the TSA.
>>>
>>> Signed-off-by: Herve Codina <herve.codina@xxxxxxxxxxx>
>>
>> In some places, you comments use the network style, not the generic style.
>
> I will fix them.
>
>>
>> Christophe
>
> Thanks for the review,
> Hervé
>