Re: [PATCH v3 6/7] mmc: sdhci_am654: Fix SDHCI_RESET_ALL for CQHCI

Florian Fainelli
2022-10-25T23:29:57Z

On 10/25/22 15:26, Brian Norris wrote:
> On Tue, Oct 25, 2022 at 02:53:46PM -0700, Florian Fainelli wrote:
>> On 10/25/22 14:45, Brian Norris wrote:
>>> On Tue, Oct 25, 2022 at 04:10:44PM +0300, Adrian Hunter wrote:
>>>> On 24/10/22 20:55, Brian Norris wrote:
>>>>> diff --git a/drivers/mmc/host/sdhci_am654.c b/drivers/mmc/host/sdhci_am654.c
>>>>> index 8f1023480e12..6a282c7a221e 100644
>>>>> --- a/drivers/mmc/host/sdhci_am654.c
>>>>> +++ b/drivers/mmc/host/sdhci_am654.c
>>>
>>>>> @@ -378,7 +379,7 @@ static void sdhci_am654_reset(struct sdhci_host *host, u8 mask)
>>>>> struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
>>>>> struct sdhci_am654_data *sdhci_am654 = sdhci_pltfm_priv(pltfm_host);
>>>>> - sdhci_reset(host, mask);
>>>>> + sdhci_and_cqhci_reset(host, mask);
>>>>> if (sdhci_am654->quirks & SDHCI_AM654_QUIRK_FORCE_CDTEST) {
>>>>> ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL);
>>>>
>>>> What about sdhci_reset in sdhci_am654_ops ?
>>>
>>> Oops, I think you caught a big fallacy in some of my patches: I assumed
>>> there was a single reset() implementation in a given driver (an unwise
>>> assumption, I realize). I see at least sdhci-brcmstb.c also has several
>>> variant ops that call sdhci_reset(), and I should probably convert them
>>> too.
>>
>> You got it right for sdhci-brcmstb.c because "supports-cqe" which gates the
>> enabling of CQE can only be found with the "brcm,bcm7216-sdhci" compatible
>> which implies using brcmstb_reset().
>
> I don't see any in-tree device trees for these chips (which is OK), and
> that's not what the Documentation/ says, and AFAICT nothing in the
> driver is limiting other variants from specifying the "supports-cqe"
> flag in their (out-of-tree) device tree. The closest thing I see is that
> an *example* in brcm,sdhci-brcmstb.yaml shows "supports-cqe" only on
> brcm,bcm7216-sdhci -- but an example is not a binding agreement. Am I
> missing something?
>
> Now of course, you probably know behind the scenes that there are no
> other sdhci-brcmstb-relevant controllers that "support cqe", but AFAICT
> I have no way of knowing that a priori. The driver and bindings give
> (too much?) flexibility.

Yes that is fair enough, I will amend the binding document to make it
clearer that 'supports-cqe' only applies in case of "brcm,bcm7216-sdhci"
and not for other compatibles.
--
Florian