linux-kernel - Re: [PATCH v2 2/2] clocksource/drivers/mtk_systimer: Add support for Mediatek SoCs

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: <1530093016.17448.35.camel@mtkswgap22>
Date:   Wed, 27 Jun 2018 17:50:16 +0800
From:   Stanley Chu <stanley.chu@...iatek.com>
To:     Daniel Lezcano <daniel.lezcano@...aro.org>
CC:     Matthias Brugger <matthias.bgg@...il.com>,
        Thomas Gleixner <tglx@...utronix.de>,
        Rob Herring <robh+dt@...nel.org>,
        <linux-kernel@...r.kernel.org>,
        <linux-mediatek@...ts.infradead.org>, <devicetree@...r.kernel.org>,
        <wsd_upstream@...iatek.com>
Subject: Re: [PATCH v2 2/2] clocksource/drivers/mtk_systimer: Add support
 for Mediatek SoCs

On Wed, 2018-06-27 at 11:39 +0200, Daniel Lezcano wrote:
> On 27/06/2018 09:53, Stanley Chu wrote:
> > This patch adds a new clock event for the timer
> > found on the Mediatek SoCs.
> > 
> > The Mediatek System Timer has several 32-bit timers.
> > Only one timer is used by this driver as a clock event
> > supporting oneshot events.
> > 
> > The System Timer can be run with two clocks. A 13 MHz system
> > clock and the RTC clock running at 32 KHz. This implementation
> > uses the system clock with no clock source divider.
> 
> Recent platforms have the arch_arm_timer and it will be always selected.
> 
> What is the benefit of adding this timer ?
> 
> 
Hi Daniel,

To save power as much as possible, our platform enables
"arch_timer_c3stop" in arch_arm_timer, and thus another always-on timer
is required for tick-broadcasting. System Timer is introduced for above
purpose.

Thanks.
Stanley Chu