Re: [PATCH v2] brcmfmac: Add support for BCM43596 PCIe Wi-Fi

From: Alvin Šipraga
Date: Thu Sep 22 2022 - 09:31:13 EST


On Thu, Sep 22, 2022 at 03:02:12PM +0200, Linus Walleij wrote:
> On Thu, Sep 22, 2022 at 12:21 PM Konrad Dybcio
> <konrad.dybcio@xxxxxxxxxxxxxx> wrote:
>
> > Also worth noting is the 'somc' bit, meaning there are probably *some* SONY
> > customizations, but that's also just a guess.
>
> What I have seen from BRCM customizations on Samsung phones is that
> the per-device customization of firmware seems to involve the set-up of
> some GPIO and power management pins. For example if integrated with
> an SoC that has autonomous system resume, or if some GPIO line has
> to be pulled to enable an external regulator or PA.

At least with Infineon (formerly Cypress), as a customer you might get a
private firmware and this will be maintained internally by them on a
separate customer branch. Any subsequent bugfixes or feature requests
will usually be applied to that customer branch and a new firmware built
from it. I think their internal "mainline" branch might get merged into
the customer branches from time to time, but this seems to be done on an
ad-hoc basis. This is our experience at least.

I would also point out that the BCM4359 is equivalent to the
CYW88359/CYW89359 chipset, which we are using in some of our
products. Note that this is a Cypress chipset (identifiable by the
Version: ... (... CY) tag in the version string). But the FW Konrad is
linking appears to be for a Broadcom chipset.

FYI, here's a publicly available set of firmware files for the '4359:

https://github.com/NXP/imx-firmware/tree/master/cyw-wifi-bt/1FD_CYW4359

Anyway, I would second Hector's suggestion and make this a separate FW.

>
> To the best of my knowledge that customization is done by consultants
> from Broadcom when working with the device manufacturer, and
> eventually they roll a unique firmware for the device. Probably because
> the firmware can only be signed for execution by Broadcom?

Kind regards,
Alvin

>
> Yours,
> Linus Walleij