Re: [PATCH 0/6] arm64: dts: qcom: sc8280xp: set GPI DMA channels according to DSDT

[Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>]

On 6/7/26 10:49 AM, Icenowy Zheng wrote:
> 在 2026-06-06六的 21:51 +0800，Pengyu Luo写道：
>> On Sat, Jun 6, 2026 at 9:21 PM Icenowy Zheng
>> <zhengxingda@iscas.ac.cn> wrote:
>>>
>>> 在 2026-06-06六的 17:46 +0800，Pengyu Luo写道：
>>>> On 2026-06-06 17:28:35+08:00, Icenowy Zheng wrote:
>>>>> 在 2026-06-06六的 17:22 +0800，Pengyu Luo写道：
>>>>>
>>>>>> On 2026-06-02 21:21:27+08:00, Icenowy Zheng wrote:
>>>>>>
>>>>>> The magnetic keyboard (USB HID) can't be connected somehow,
>>>>>> others
>>>>>> are
>>>>>> fine, such as the spi touchscreen (not upstream yet), which
>>>>>> utilizes
>>>>>> DMA definitely. My config is here
>>>>>> https://pastebin.com/SdjuyJYk
>>>>>
>>>>> Is this a defconfig?
>>>>>
>>>>
>>>> Yes.
>>>>
>>>>> BTW it seems that CONFIG_ASYNC_TX_DMA needs to be selected too
>>>>> for
>>>>> exhibiting the problem (because there should be "public" GPI
>>>>> DMA
>>>>> consumers to trigger the stuck/reset).
>>>>>
>>>>
>>>> Is this still necessary? I checked the fedora discussion and your
>>>> GPI
>>>> DMA fix. And GPI DMA is only for the QUP-supported peripherals as
>>>> the
>>>> binding mentioned, devicetree/bindings/dma/qcom,gpi.yaml
>>>
>>> The devicetree without this fix seems to be still incorrect,
>>> because
>>> with the device tree fix even if the GPI DMA driver misbehaves the
>>> system won't be stuck (although it will iterate all GPI channels
>>> and
>>> then fail to function at all).
>>>
>>
>> Back to the start. You said some GPI interfaces aren't available to
>> HLOS, your mask is 0xb(0b1011), so I use 0x4(0b100) did a quick test,
>> and spi6 consumed it, no stuck or reset. Could you give me a
>> unavailable channel?
> 
> I think channel 0b10000 of gpi_dma2 could be an example?
> 
> It seems that 4 channels are tried on gpi_dma2 before hang on my
> gaokun3, but as gaokun3 has no known serial access, it's possible that
> 0b100000 or 0b1000 is problematic.
> 
> (The reason gpi_dma2 is checked first is because it's the GPI DMA
> controller with the smallest address)
> 
> BTW I just took the values from Windows DSDT, which is quite
> conservative.

So, with DMA_PRIVATE set, is this series made redundant?

Konrad