linux-kernel - Re: [PATCH 2/3] drivers: bus: simple-pm-bus: Use clocks

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: <4697e12b-e9e3-100e-190c-7eece43b3a05@linaro.org>
Date:   Tue, 2 Aug 2022 12:59:30 +0200
From:   Krzysztof Kozlowski <krzysztof.kozlowski@...aro.org>
To:     Liu Ying <victor.liu@....com>, devicetree@...r.kernel.org,
        linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org
Cc:     robh+dt@...nel.org, krzysztof.kozlowski+dt@...aro.org,
        shawnguo@...nel.org, s.hauer@...gutronix.de, kernel@...gutronix.de,
        festevam@...il.com, linux-imx@....com, saravanak@...gle.com,
        gregkh@...uxfoundation.org, geert+renesas@...der.be
Subject: Re: [PATCH 2/3] drivers: bus: simple-pm-bus: Use clocks

On 02/08/2022 12:56, Krzysztof Kozlowski wrote:
> On 02/08/2022 09:13, Liu Ying wrote:
>> Simple Power-Managed bus controller may need functional clock(s)
>> to be enabled before child devices connected to the bus can be
>> accessed.  Get the clock(s) as a bulk and enable/disable the
>> clock(s) when the bus is being power managed.
>>
>> One example is that Freescale i.MX8qxp pixel link MSI bus controller
>> needs MSI clock and AHB clock to be enabled before accessing child
>> devices.
> 
> No, because it is not simple bus anymore.

Hm, actually I take back my no, as this pm-bus was done for such
purpose. Since we allow power domains, we should also allow clocks.

Best regards,
Krzysztof