Re: [PATCH net-next v2 2/7] net: airoha: npu: Add NPU wlan memory initialization commands

[Krzysztof Kozlowski <krzk@kernel.org>]

On 07/07/2025 17:04, Krzysztof Kozlowski wrote:
> On 07/07/2025 09:24, Lorenzo Bianconi wrote:
>>> On Sat, Jul 05, 2025 at 11:09:46PM +0200, Lorenzo Bianconi wrote:
>>>> +
>>>>  struct airoha_npu *airoha_npu_get(struct device *dev, dma_addr_t *stats_addr)
>>>>  {
>>>>  	struct platform_device *pdev;
>>>> @@ -493,6 +573,7 @@ static int airoha_npu_probe(struct platform_device *pdev)
>>>>  	npu->ops.ppe_deinit = airoha_npu_ppe_deinit;
>>>>  	npu->ops.ppe_flush_sram_entries = airoha_npu_ppe_flush_sram_entries;
>>>>  	npu->ops.ppe_foe_commit_entry = airoha_npu_foe_commit_entry;
>>>> +	npu->ops.wlan_init_reserved_memory = airoha_npu_wlan_init_memory;
>>>
>>> I cannot find in your code single place calling this (later you add a
>>> wrapper... which is not called either).
>>>
>>> All this looks like dead code...
>>
>> As pointed out in the commit log, these callbacks will be used by MT76 driver
>> to initialize the NPU reserved memory and registers during driver probe in
>> order to initialize the WiFi offloading. Since MT76 patches are going via
>> the wireless tree, I needed to add these callbacks first.
> 
> Cover letter does not link to your NPU patchset. You cannot add dead
> code to the kernel and now it is pure dead code. Post your user - in
> this or separate patchset.
> 
> Your explanation of dependency is also confusing. If these are added to
> wireless tree (considering last experience how they rebase and cannot

... I think I mixed, that was Bluetooth tree which had rebases and
messed cross tree, not wifi. Apologies for confusion.

> easily handle cross tree merges), how does it solve your problem? You
> will have it in one tree but not in the other, so still nothing...
> That's anyway separate problem, because main issue is you add code which
> we cannot even verify how it is being used.
> 
> So far I see ABI break, but without user cannot judge. And that's the
> hard reason this cannot be accepted.

Best regards,
Krzysztof