linux-kernel - Re: [PATCH] drm/omap: Migrate minimum FCK/PCK ratio from Kconfig to dts

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: <2cff2d77-485d-c9a5-ea9b-a9146a81218e@ti.com>
Date:   Tue, 1 Oct 2019 08:12:44 +0300
From:   Tero Kristo <t-kristo@...com>
To:     Tomi Valkeinen <tomi.valkeinen@...com>,
        Adam Ford <aford173@...il.com>
CC:     "H. Nikolaus Schaller" <hns@...delico.com>,
        Tony Lindgren <tony@...mide.com>,
        Linux-OMAP <linux-omap@...r.kernel.org>,
        Adam Ford <adam.ford@...icpd.com>,
        Benoît Cousson <bcousson@...libre.com>,
        dri-devel <dri-devel@...ts.freedesktop.org>,
        devicetree <devicetree@...r.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] drm/omap: Migrate minimum FCK/PCK ratio from Kconfig to
 dts

On 01/10/2019 08:07, Tomi Valkeinen wrote:
> On 30/09/2019 20:48, Tero Kristo wrote:
> 
>> Hmmh, after some testing, it seems there is bad stuff happening with 
>> the divider clock implementation, I am re-working it as of now. 
>> Basically what is wrong is that with a divider max value of say 16, 
>> the driver attempts to craft the max value into a mask, but this ends 
>> up being 0x1f. If the max value is 15, it ends up into 0xf which is 
>> correct.
> 
> Ok, that explains the max not working.
> 
> It doesn't explain the other issue, where the TRM says the max div is 
> 32, but it does not work. But taking the max div from the old SoCs, 16, 
> is not correct either, as it seems that dividers up to 31 work ok.

If someone knows for sure that dividers higher than 16 are fine on 
omap36xx, we can add this under omap36xx-clocks.dtsi. Anyway, let me fix 
the broken divider max logic first, that seems to be more pressing issue.

-Tero

--
Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki