Re: [PATCH 2/2] spi: qcom-geni: Add property to force GSI mode

From: Konrad Dybcio

Date: Thu Jul 02 2026 - 08:53:39 EST


On 6/30/26 12:06 PM, Pengyu Luo wrote:
> On Tue, Jun 30, 2026 at 5:52 PM Mukesh Savaliya
> <mukesh.savaliya@xxxxxxxxxxxxxxxx> wrote:
>>
>>
>>
>> On 6/29/2026 1:33 PM, Pengyu Luo wrote:
>>> On Mon, Jun 29, 2026 at 1:36 PM Mukesh Savaliya
>>> <mukesh.savaliya@xxxxxxxxxxxxxxxx> wrote:
>>>>
>>>> Hi Pengyu,
>>>>
>>>> On 6/15/2026 2:48 AM, Dmitry Baryshkov wrote:
>>>>> On Sun, Jun 14, 2026 at 04:34:24PM +0800, Pengyu Luo wrote:
>>>>>> Some devices (such as gaokun3) do not disable FIFO mode, causing the
>>>>>> driver to fallback to FIFO mode by default. However, these platforms
>>>>>> also support GSI mode, which is highly preferred for certain
>>>>>> peripherals like SPI touchscreens to improve performance.
>>>>>>
>>>>>> Introduce the "qcom,force-gsi-mode" device property to hint and force
>>>>>> the controller into GSI mode during initialization.
>>>> Why to force ? You can directly configure in GSI mode. Note there are
>>>> some configuration done prior to Linux bootup too.
>>>
>>> Sorry, I don't get it. how? I know there may be a qupfw, but it is
>>> impossible for a normal user like me to generate one with GSI
>>> preferred.
>>>
>> If firmware doesn't program in GSI, you can't have this working in GSI
>> mode, its going to fail (and work with fallback). if it's programmed in
>> GSI, anyway this will run in GSI mode. So why to add extra things
>> without any usage ?
>>
>
> What I can confirm is that fifo is not disabled on my device, and gsi
> is definitely enabled (under windows, check the register
> SE_GENI_DMA_MODE_EN), forcing the device to enable GSI mode on linux
> works well.

What's the value of se->base + SE_DMA_IF_EN (+0x2004) on this SE?

Konrad