Re: [PATCH] soc: qcom: Introduce WCNSS_CTRL SMD client

[yfw <fengwei.yin@linaro.org>]

Hi Bjorn,

On 2015/10/22 21:50, Bjorn Andersson wrote:
> On Thu 22 Oct 03:25 PDT 2015, yfw wrote:
>
>> Hi Bjorn,
>>
>> On 2015/9/22 1:52, Bjorn Andersson wrote:
> [..]
>>
>> I have a question: Do you have plan to add the nob to trigger wcnss firmware
>> downloading which is also common for wifi and BT?
>>
>
> In caf the wcnss driver is actually two drivers intermingled;
> * a SMD client driver, responsible for pushing NV, something related to
>    calibration, some power properties and so on
>
> * a platform_driver implementing the wcnss specifics of the PIL through
>    some hooks and providing the knob to trigger the PIL.
>
> The first driver is related to the "OS" running on the wcnss, so that
> should follow the life cycle of the SMD channel "WCNSS_CTRL". This is
> what this patch provides - it loads the NV every time the wcnss core is
> booted.
>
>
> For the second part, I strongly believe that the PIL implementation
> should deal with the specifics (e.g. regulator handling and
> xo_calibration), rather than having a piece bolted on elsewhere - so
> that's in the remoteproc-wcnss driver.
>
Yes. I meant this remoteproc-wcnss driver. Will you try to upstream it?

>
> Left is a mechanism to trigger the thing to boot and shutdown. One
> potential solution would be to have the module_init/exit call
> rproc_boot/shutdown from the WiFi & BT drivers. That way if one loads
> the wcn36xx driver, the core is booted. This would also fit quite nicely
> for other things - e.g. load the ALSA driver to trigger the ADSP
> loading.
>
> The problem here is that we're then forced to either have a method of
> deferring the rproc_boot() until the firmware is available or we always
> must compile these drivers as kernel modules. This because the
> file system isn't there during boot to provide the firmware.
The firmware file could be put to initrd. That should allow wcn wifi driver
builtin.

>
> We do have the same thing in e.g. the Broadcom WiFi/BT solution and
> there seems to be discussions related to this.
>
>
> So for now, I punted and put a knob in the wcnss remoteproc driver.
>
> Regards,
> Bjorn
>

Regards
Yin, Fengwei