linux-kernel - Re: [PATCH net-next v2 16/18] MIPS: mobileye: add EyeQ5 DMA IOCU support

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] [day] [month] [year] [list]

Message-Id: <DBWBSL7Q35M2.2WWW5HKBHKUA5@bootlin.com>
Date: Thu, 07 Aug 2025 18:11:23 +0200
From: Théo Lebrun <theo.lebrun@...tlin.com>
To: "Jiaxun Yang" <jiaxun.yang@...goat.com>, "Andrew Lunn"
 <andrew+netdev@...n.ch>, "David S . Miller" <davem@...emloft.net>, "Eric
 Dumazet" <edumazet@...gle.com>, "Jakub Kicinski" <kuba@...nel.org>, "Paolo
 Abeni" <pabeni@...hat.com>, "Rob Herring" <robh@...nel.org>, "Krzysztof
 Kozlowski" <krzk+dt@...nel.org>, "Conor Dooley" <conor+dt@...nel.org>,
 "Nicolas Ferre" <nicolas.ferre@...rochip.com>, "Claudiu Beznea"
 <claudiu.beznea@...on.dev>, "Paul Walmsley" <paul.walmsley@...ive.com>,
 "Palmer Dabbelt" <palmer@...belt.com>, "Albert Ou" <aou@...s.berkeley.edu>,
 "Alexandre Ghiti" <alex@...ti.fr>, "Samuel Holland"
 <samuel.holland@...ive.com>, "Richard Cochran" <richardcochran@...il.com>,
 "Russell King" <linux@...linux.org.uk>, "Thomas Bogendoerfer"
 <tsbogend@...ha.franken.de>, "Vladimir Kondratiev"
 <vladimir.kondratiev@...ileye.com>, "Gregory CLEMENT"
 <gregory.clement@...tlin.com>, "Cyrille Pitchen"
 <cyrille.pitchen@...el.com>, "Harini Katakam" <harini.katakam@...inx.com>,
 "Rafal Ozieblo" <rafalo@...ence.com>, "Haavard Skinnemoen"
 <hskinnemoen@...el.com>
Cc: <netdev@...r.kernel.org>, <devicetree@...r.kernel.org>,
 <linux-kernel@...r.kernel.org>, <linux-riscv@...ts.infradead.org>,
 "linux-mips@...r.kernel.org" <linux-mips@...r.kernel.org>, "Thomas
 Petazzoni" <thomas.petazzoni@...tlin.com>, "Tawfik Bayouk"
 <tawfik.bayouk@...ileye.com>
Subject: Re: [PATCH net-next v2 16/18] MIPS: mobileye: add EyeQ5 DMA IOCU
 support

Hello Jiaxun,

On Mon Jun 30, 2025 at 3:35 PM CEST, Jiaxun Yang wrote:
> 在2025年6月27日周五 上午10:09，Théo Lebrun写道：
>> Both Cadence GEM Ethernet controllers on EyeQ5 are hardwired through CM3
>> IO Coherency Units (IOCU). For DMA coherent accesses, BIT(36) must be
>> set in DMA addresses.
>
> Just quick question, it seems like this special driver is only applying a
> fixed offset (1 << 36) to the DMA physical address, can we achieve that with dma-ranges
> property in DeviceTree?
>
> I belive:
> ```
> dma-coherent;
>              # Bus addr       # Phys  # Size
> dma-ranges = <0x10 0x00000000 0x0 0x0 0x10 0>;
> ```
>
> Will do the job.

This is perfect! Can confirm it works just fine. When you are stuck in
an issue for too long you don't think about broadening your viewpoint.

Thanks,

--
Théo Lebrun, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com