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Date:   Tue, 12 Oct 2021 17:14:24 +0800
From:   Baochen Qiang <bqiang@codeaurora.org>
To:     Kalle Valo <kvalo@codeaurora.org>
Cc:     ath11k@lists.infradead.org, linux-wireless@vger.kernel.org
Subject: Re: [PATCH] ath11k: Advertise PLATFORM_CAP_PCIE_GLOBAL_RESET in qmi
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On 2021-10-11 14:30, Kalle Valo wrote:
> Baochen Qiang <bqiang@codeaurora.org> writes:
> 
>> Inform firmware that host is capable of triggering a global reset.
>> This is requested by firmware team.
> 
> Why?
> 
> https://wireless.wiki.kernel.org/en/users/drivers/ath10k/submittingpatches#answer_to_why

In some scenarios like rmmod/insmod, HW target needs to be completely 
reset. On ARM platforms we can rely on WL_EN pin and other power 
regulators to do this. However on x86 or some third party platforms, 
this has to be done by ath11k host by writing HW register 
PCIE_SOC_GLOBAL_RESET. But the problem is that some HW registers can not 
be cleared/restored. With this flag PLATFORM_CAP_PCIE_GLOBAL_RESET in 
QMI host_cap message, firmware can do some platform specific operations 
to fix this issue.