linux-kernel - Re: [PATCH 07/11] dt-bindings: spi: spi-nxp-fspi: add a new property nxp,fspi-dll-slvdly

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 for Android: free password hash cracker in your pocket

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

Message-ID: <20220705143100.kkyjzllastptaoqe@umbrella>
Date:   Tue, 5 Jul 2022 09:31:00 -0500
From:   Han Xu <han.xu@....com>
To:     Krzysztof Kozlowski <krzysztof.kozlowski@...aro.org>
Cc:     Bough Chen <haibo.chen@....com>,
        "ashish.kumar@....com" <ashish.kumar@....com>,
        "yogeshgaur.83@...il.com" <yogeshgaur.83@...il.com>,
        "broonie@...nel.org" <broonie@...nel.org>,
        "robh+dt@...nel.org" <robh+dt@...nel.org>,
        "krzysztof.kozlowski+dt@...aro.org" 
        <krzysztof.kozlowski+dt@...aro.org>,
        "singh.kuldeep87k@...il.com" <singh.kuldeep87k@...il.com>,
        "tudor.ambarus@...rochip.com" <tudor.ambarus@...rochip.com>,
        "p.yadav@...com" <p.yadav@...com>,
        "michael@...le.cc" <michael@...le.cc>,
        "miquel.raynal@...tlin.com" <miquel.raynal@...tlin.com>,
        "richard@....at" <richard@....at>,
        "vigneshr@...com" <vigneshr@...com>,
        "shawnguo@...nel.org" <shawnguo@...nel.org>,
        "s.hauer@...gutronix.de" <s.hauer@...gutronix.de>,
        "kernel@...gutronix.de" <kernel@...gutronix.de>,
        "linux-spi@...r.kernel.org" <linux-spi@...r.kernel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "devicetree@...r.kernel.org" <devicetree@...r.kernel.org>,
        "linux-mtd@...ts.infradead.org" <linux-mtd@...ts.infradead.org>,
        "festevam@...il.com" <festevam@...il.com>,
        dl-linux-imx <linux-imx@....com>,
        "linux-arm-kernel@...ts.infradead.org" 
        <linux-arm-kernel@...ts.infradead.org>,
        "zhengxunli@...c.com.tw" <zhengxunli@...c.com.tw>
Subject: Re: [PATCH 07/11] dt-bindings: spi: spi-nxp-fspi: add a new property
 nxp,fspi-dll-slvdly

On 22/07/05 04:03PM, Krzysztof Kozlowski wrote:
> On 05/07/2022 16:00, Han Xu wrote:
> >> So we probably misunderstood each other... looking at the driver it also explains
> >> the confusing. You encoded here register value which is pretty often wrong
> >> approach.
> >>
> >> This should be instead meaningful value for the user of the bindings, so usually
> >> using one of property units:
> >> https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2F&amp;data=05%7C01%7Chan.xu%40nxp.com%7C8b8e3e6291c24579020308da5e8f2916%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C637926266207468995%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&amp;sdata=KHgjKLX7M8CYfJoWqpVhNdZc%2FlZhZxp6CuaPTUYgwE8%3D&amp;reserved=0
> >> %2Fdevicetree-org%2Fdt-
> >> schema%2Fblob%2Fmain%2Fdtschema%2Fschemas%2Fproperty-
> >> units.yaml&amp;data=05%7C01%7Chan.xu%40nxp.com%7C0ffe3d706e064f14382
> >> 108da5e8a5add%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C6379262
> >> 45564450475%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV
> >> 2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&amp;sdata=Q4
> >> SfVnBN%2BQ0vYKJzRf%2FXZkCA1WGyPV9doFcb%2BLSKx4w%3D&amp;reserved=0
> >>
> >> I think you could use here clock cycles or clock phase, but then it has to be obvious
> >> it is that unit.
> > 
> > Hi Krzysztof, 
> > 
> > Let me clarify it, in the document a term "delay cell" was used to descript this register bit. 
> 
> Which document? The bindings (I cannot find it there)? Commit msg?

The SoC Reference Manual.

> 
> > Each delay cell equals "1/32 clock phase", so the unit of delay cell is clock phase. The value user need set in DT just number to define how many delay cells needed.
> 
> Your bindings did not say this at all.

I will explain all details in v2 patch.

> 
> Best regards,
> Krzysztof