linux-kernel - Re: [PATCH v9 27/28] media: iris: enable video driver probe of SM8250 SoC

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <c0f59149-713b-45e4-3755-4a52cfaa93f6@quicinc.com>
Date: Wed, 8 Jan 2025 13:13:30 +0530
From: Dikshita Agarwal <quic_dikshita@...cinc.com>
To: Nicolas Dufresne <nicolas@...fresne.ca>,
        Mauro Carvalho Chehab
	<mchehab+huawei@...nel.org>,
        Sebastian Fricke
	<sebastian.fricke@...labora.com>
CC: Vikash Garodia <quic_vgarodia@...cinc.com>,
        Abhinav Kumar
	<quic_abhinavk@...cinc.com>,
        Mauro Carvalho Chehab <mchehab@...nel.org>,
        "Rob
 Herring" <robh@...nel.org>,
        Krzysztof Kozlowski <krzk+dt@...nel.org>,
        "Conor
 Dooley" <conor+dt@...nel.org>,
        Philipp Zabel <p.zabel@...gutronix.de>,
        "Hans
 Verkuil" <hverkuil@...all.nl>,
        Bryan O'Donoghue <bryan.odonoghue@...aro.org>,
        Dmitry Baryshkov <dmitry.baryshkov@...aro.org>,
        Neil Armstrong
	<neil.armstrong@...aro.org>,
        Uwe Kleine-König
	<u.kleine-koenig@...libre.com>,
        Jianhua Lu <lujianhua000@...il.com>,
        "Stefan
 Schmidt" <stefan.schmidt@...aro.org>,
        <linux-media@...r.kernel.org>, <linux-arm-msm@...r.kernel.org>,
        <devicetree@...r.kernel.org>, <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH v9 27/28] media: iris: enable video driver probe of SM8250
 SoC



On 1/7/2025 7:27 PM, Nicolas Dufresne wrote:
> Le lundi 23 décembre 2024 à 16:21 +0530, Dikshita Agarwal a écrit :
>>
>> On 12/23/2024 4:00 PM, Mauro Carvalho Chehab wrote:
>>> Em Thu, 12 Dec 2024 17:21:49 +0530
>>> Dikshita Agarwal <quic_dikshita@...cinc.com> escreveu:
>>>
>>>> +	.dma_mask = GENMASK(31, 29) - 1,
>>>
>>> Setting a mask to GENMASK() - 1 sounds weird. Is it really what you want?
>>> I so, why?
>>>
>> Hi Mauro,
>>
>> the value of this dma mask should be 0xe0000000 -1.
>>
>> The background for the same is, 0xe0000000 onward memory space is allocated
>> for IO register space so we are restricting the driver buffer allocations
>> to 0xe0000000 - 1.
>>
>> Based on the comments received in the past, we are using GENMASK to
>> generate 0xe0000000.
>>
>> Does this answer your query or I missed something?
> 
> I'm not sure it will do what you want. (0xe0000000 -1) matches ~BIT(29). Perhaps
> you wanted to use ~0xe0000000. 
> 
value of dma mask is coming as expected with GENMASK(31, 29) - 1

qcom-iris aa00000.video-codec: dma_mask DFFFFFFF (0xe0000000 -1)

Thanks,
Dikshita
> Nicolas
> 
>>
>> Thanks,
>> Dikshita
>>> Thanks,
>>> Mauro
>