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Re: [PATCH v2] MIPS: GIC: Select R4K counter as fallback.

To: Lars-Peter Clausen <lars@metafoo.de>
Subject: Re: [PATCH v2] MIPS: GIC: Select R4K counter as fallback.
From: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Date: Thu, 12 Sep 2013 11:23:53 -0700
Cc: "Steven J. Hill" <Steven.Hill@imgtec.com>, <linux-mips@linux-mips.org>, <ralf@linux-mips.org>
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On 09/12/2013 12:28 AM, Lars-Peter Clausen wrote:
On 09/11/2013 09:51 PM, Steven J. Hill wrote:
From: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>

If CONFIG_CSRC_GIC is selected and the GIC is not found during
boot, then fallback to the R4K counter gracefully.
Is there any reason not to always register the r4k clocksource, no matter
whether the gic clocksource is present or not? The timekeeping core of the
kernel will make sure to use the best available clocksource based on the
clocksource's rating.

- Lars
If you do power saving by switching some core OFF then you should do an additional clock sync after core revival. GIC is free from that but R4K is not. It was a primary reason for GIC clocksource.

- Leonid.



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