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

From: Icenowy Zheng

Date: Sun Jun 07 2026 - 04:50:13 EST


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@xxxxxxxxxxx> 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.

Thanks,
Icenowy

>
> Best wishes,
> Pengyu