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Message-ID: <68a49964-7c05-4575-a4f3-35848c08fefc@freebox.fr>
Date: Mon, 4 Mar 2024 17:21:37 +0100
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Subject: Re: [PATCH 1/2] dt-bindings: net: wireless: ath10k: add
 qcom,no-msa-ready-indicator prop
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To: Conor Dooley <conor@kernel.org>, Kalle Valo <kvalo@kernel.org>
Cc: Jeff Johnson <quic_jjohnson@quicinc.com>,
 ath10k <ath10k@lists.infradead.org>,
 wireless <linux-wireless@vger.kernel.org>, DT <devicetree@vger.kernel.org>,
 Rob Herring <robh+dt@kernel.org>,
 Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
 Conor Dooley <conor+dt@kernel.org>,
 Pierre-Hugues Husson <phhusson@freebox.fr>,
 Jami Kettunen <jamipkettunen@gmail.com>,
 Jeffrey Hugo <quic_jhugo@quicinc.com>,
 Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
References: <14daa98e-7fd3-4ebb-87bb-5d2c1fba679f@freebox.fr>
 <b8de96c7-cbb6-4a09-a4d4-2c11b3ab3e01@freebox.fr> <871q8wk7o3.fsf@kernel.org>
 <3392f356-7b19-483d-b9f8-3bd84068fa52@freebox.fr> <87wmqoilzf.fsf@kernel.org>
 <20240229-ageless-primal-7a0544420949@spud>
From: Marc Gonzalez <mgonzalez@freebox.fr>
In-Reply-To: <20240229-ageless-primal-7a0544420949@spud>
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On 29/02/2024 19:40, Conor Dooley wrote:

> On Wed, Feb 28, 2024 at 06:37:08PM +0200, Kalle Valo wrote:
>
>> Marc Gonzalez wrote:
>> 
>>> As mentioned in my other reply, there are several msm8998-based
>>> devices affected by this issue. Is it not appropriate to consider
>>> a kernel-based work-around?
>>
>> Sorry, not following you here. But I'll try to answer anyway:
>>
>> I have understood that Device Tree is supposed to describe hardware, not
>> software. This is why having this property in DT does not look right
>> place for this. For example, if the ath10k firmware is fixed then DT
>> would have to be changed even though nothing changed in hardware. But of
>> course DT maintainers have the final say.
> 
> I dunno, if the firmware affects the functionality of the hardware in a
> way that cannot be detected from the operating system at runtime how
> else is it supposed to deal with that?
> The devicetree is supposed to describe hardware, yes, but at a certain
> point the line between firmware and hardware is invisible :)
> Not describing software is mostly about not using it to determine
> software policy in the operating system.

Recording here what was discussed a few days ago on IRC:

If all msm8998 boards are affected, then it /might/ make sense
to work around the issue for ALL msm8998 boards:

diff --git a/drivers/net/wireless/ath/ath10k/qmi.c b/drivers/net/wireless/ath/ath10k/qmi.c
index 0776e79b25f3a..9da06da518fb6 100644
--- a/drivers/net/wireless/ath/ath10k/qmi.c
+++ b/drivers/net/wireless/ath/ath10k/qmi.c
@@ -1076,6 +1076,9 @@ int ath10k_qmi_init(struct ath10k *ar, u32 msa_size)
 	qmi->ar = ar;
 	ar_snoc->qmi = qmi;
 
+	if (of_device_is_compatible(of_root, "qcom,msm8998")
+		qmi->no_point_in_waiting_for_msa_ready_indicator = true;
+
 	if (of_property_read_bool(dev->of_node, "qcom,msa-fixed-perm"))
 		qmi->msa_fixed_perm = true;
 

Thus, anyone porting an msm8998 board to mainline would automatically
get the work-around, without having to hunt down the feature bit,
and tweak the FW files.


-- 
Regards