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Message-ID: <991e7861-0c6e-4c77-a866-4295d775df35@quicinc.com>
Date: Mon, 3 Jun 2024 07:22:06 -0700
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Subject: Re: [PATCH v3 6/8] wifi: ath12k: support ARP and NS offload
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To: Baochen Qiang <quic_bqiang@quicinc.com>, <ath12k@lists.infradead.org>
CC: <linux-wireless@vger.kernel.org>
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 <0a386734-5796-4d99-ad4b-ee0a5653a25e@quicinc.com>
From: Jeff Johnson <quic_jjohnson@quicinc.com>
In-Reply-To: <0a386734-5796-4d99-ad4b-ee0a5653a25e@quicinc.com>
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On 6/2/2024 7:48 PM, Baochen Qiang wrote:
> 
> 
> On 6/1/2024 1:26 AM, Jeff Johnson wrote:
>> On 5/30/2024 10:11 PM, Baochen Qiang wrote:
>>>
>>>
>>> On 5/31/2024 11:42 AM, Baochen Qiang wrote:
>>>>>> +static void ath12k_wow_prepare_ns_offload(struct ath12k_vif *arvif,
>>>>>> +					  struct wmi_arp_ns_offload_arg *offload)
>>>>>> +{
>>>>>> +	struct inet6_dev *idev = arvif->idev;
>>>>> as noted above does it make more sense to get the netdev associated with the
>>>>> arvif and then use in6_dev_get(net_device) to get the inet6_dev rather than
>>>>> caching the pointer from the ipv6_addr_changed() callback?
>>>> Ah.. I didn't note that we can get inet6_dev in such a way, just thought the only way is to cache it in ipv6_changed() callback.
>>>>
>>>> will get it using the following in next version:
>>>> 	struct ieee80211_vif *vif = container_of(arvif)
>>>> 	struct ieee80211_sub_if_data *sub_if_data = container_of(vif)
>>>> 	struct net_dev *ndev = sub_if_data->dev
>>>> 	struct inet6_dev *idev = in6_dev_get(ndev)
>>> Just found that ieee80211_sub_if_data is internal to mac80211, so not possible to get netdev in this way.
>>>
>>> any other ideas on how to get netdev?
>>
>> Thinking about this some more, it seems like you'd want to send these down to
>> firmware immediately so that they'd be available for NS offload. Does firmware
>> support NS offload even when host is awake (I think the downstream Android
>> driver supports that)?
> And really curious about the use case in Android scenario.

It's all about saving power. The application processor consumes way more power
than the firmware processors, so any work that can be performed by firmware
extends battery life.

A laptop running on battery would presumably benefit from this as well.

But let's get basic functionality in place using ieee80211_vif_to_wdev()