Re: [PATCH v2 1/5] brcmfmac: Drop all the RAW device IDs

[Hector Martin]

On 05/02/2023 22.02, Hector Martin wrote:
> On 05/02/2023 21.44, Jonas Gorski wrote:
>> On Sun, 5 Feb 2023 at 07:58, Arend Van Spriel
>> <arend.vanspriel@xxxxxxxxxxxx> wrote:
>>>
>>> - stale Cypress emails
>>>
>>> On February 5, 2023 3:50:41 AM Hector Martin <marcan@xxxxxxxxx> wrote:
>>>
>>>> On 03/02/2023 02.19, Arend Van Spriel wrote:
>>>>> On February 2, 2023 6:25:28 AM "'Hector Martin' via BRCM80211-DEV-LIST,PDL"
>>>>> <brcm80211-dev-list.pdl@xxxxxxxxxxxx> wrote:
>>>>>
>>>>>> On 31/01/2023 23.17, Jonas Gorski wrote:
>>>>>>> On Tue, 31 Jan 2023 at 12:36, Hector Martin <marcan@xxxxxxxxx> wrote:
>>>>>>>>
>>>>>>>> These device IDs are only supposed to be visible internally, in devices
>>>>>>>> without a proper OTP. They should never be seen in devices in the wild,
>>>>>>>> so drop them to avoid confusion.
>>>>>>>
>>>>>>> I think these can still show up in embedded platforms where the
>>>>>>> OTP/SPROM is provided on-flash.
>>>>>>>
>>>>>>> E.g. https://forum.archive.openwrt.org/viewtopic.php?id=55367&p=4
>>>>>>> shows this bootlog on an BCM4709A0 router with two BCM43602 wifis:
>>>>>>>
>>>>>>> [    3.237132] pci 0000:01:00.0: [14e4:aa52] type 00 class 0x028000
>>>>>>> [    3.237174] pci 0000:01:00.0: reg 0x10: [mem 0x00000000-0x00007fff 64bit]
>>>>>>> [    3.237199] pci 0000:01:00.0: reg 0x18: [mem 0x00000000-0x003fffff 64bit]
>>>>>>> [    3.237302] pci 0000:01:00.0: supports D1 D2
>>>>>>> ...
>>>>>>> [    3.782384] pci 0001:03:00.0: [14e4:aa52] type 00 class 0x028000
>>>>>>> [    3.782440] pci 0001:03:00.0: reg 0x10: [mem 0x00000000-0x00007fff 64bit]
>>>>>>> [    3.782474] pci 0001:03:00.0: reg 0x18: [mem 0x00000000-0x003fffff 64bit]
>>>>>>> [    3.782649] pci 0001:03:00.0: supports D1 D2
>>>>>>>
>>>>>>> 0xaa52 == 43602 (BRCM_PCIE_43602_RAW_DEVICE_ID)
>>>>>>>
>>>>>>> Rafał can probably provide more info there.
>>>>>>>
>>>>>>> Regards
>>>>>>> Jonas
>>>>>>
>>>>>> Arend, any comments on these platforms?
>>>>>
>>>>> Huh? I already replied to that couple of days ago or did I only imagine
>>>>> doing that.
>>>>
>>>> I don't see any replies from you on the lists (or my inbox) to Jonas' email.
>>>
>>> Accidentally sent that reply to internal mailing list. So quoting myself here:
>>>
>>> """
>>> Shaking the tree helps ;-) What is meant by "OTP/SPROM is provided
>>> on-flash"? I assume you mean that it is on the host side and the wifi PCIe
>>> device can not access it when it gets powered up. Maybe for this scenario
>>> we should have a devicetree compatible to configure the device id, but that
>>> does not help any current users of these platforms. Thanks for providing
>>> this info.
>>
>> That's what I meant, the wifi chip itself does not have any (valid)
>> OTP/SPROM attached/populated, and requires the driver to setup the
>> values at runtime based on the host SoC's flash contents (most likely
>> NVRAM contents).
>>
>> This was the case in about 99% of embedded systems based on MIPS
>> bcm47xx/bcm63xx, where the wifi chips then always identified
>> themselves with their raw chip IDs as PCI device IDs (even leading to
>> one or two ID conflicts ...).
>>
>> I have to admit I don't know how much this is still an issue on
>> current (ARM) systems, but at least that one BCM4709A one suggests
>> this is still happening in "recent" designs. Probably because it saves
>> half a cent per board or so ;-)
>>
>> Regards
>> Jonas
>>
> 
> As far as I know the OTP is built into the chips themselves, and even
> Apple (who refuses to put per-device calibration data in OTP these days
> and loads it from DT) still manages to burn in the proper device ID and
> basic info at least... so I'm not sure how this saves any money. I
> thought chips weren't supposed to even leave Broadcom without at least
> an ID burned in?
> 
> - Hector

I'd like to move forward with this. Should I send a v3 without the RAW
ID removal?

- Hector