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From: Jia-Shiun Li <jiashiun@gmail.com>
Date: Mon, 30 Sep 2013 04:01:11 +0800
Message-ID: <CAHNYxxP7tc1a8W-uiL5A05qTo4wZzuydg3dtcEJWQtaxG_-grw@mail.gmail.com>
Subject: Re: BBB CPU clock (was: Re: FreeBSD on Cubieboard 2, UDOO and Galaxy
 Note 10.1 (Exynos).
To: ticso@cicely.de
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On Mon, Sep 30, 2013 at 12:41 AM, Jia-Shiun Li <jiashiun@gmail.com> wrote:
> But I manually modified registers using the sequence in mpu_pll_config() of
> u-boot and got the MPU clocked at the value I gave. There seems to be some
> unknown sequences in u-boot either skipping or overwriting MPU PLL settings.

Never mind. Have to copy MLO in addition to u-boot.img as well.
Looks like PLL init part is there.

However, I cannot set MPU clock to 800 MHz and beyond. Now booting ok at
750MHz. Maybe a heat sink or active cooling is required. Will try when
I get one.


cpufreq for ARM boards may be possible provided frequency can be changed
dynamically. But if the board cannot provide a way to determine
stability reliability it may be impractical to make it automatic.


Jia-Shiun.