[U-Boot] [U-Boot, v2, 4/4] arm: am33xx: Add support for mulitiple PLL input frequencies

[Tom Rini]

On Thu, Jun 08, 2017 at 10:17:09AM +0530, Lokesh Vutla wrote:
> 
> 
> On Thursday 08 June 2017 12:20 AM, Emmanuel Vadot wrote:
> > On Fri, 12 May 2017 13:20:50 -0400
> > Tom Rini <trini at konsulko.com> wrote:
> > 
> >> On Fri, May 05, 2017 at 12:59:10PM +0530, Lokesh Vutla wrote:
> >>
> >>> am335x supports various sysclk frequencies which can be determined
> >>> using sysboot pins. PLLs should be configures based on this
> >>> sysclk frequency. Add PLL configurations for all supported
> >>> frequencies.
> >>>
> >>> Signed-off-by: Lokesh Vutla <lokeshvutla at ti.com>
> >>> Reviewed-by: Tom Rini <trini at konsulko.com>
> >>
> >> Applied to u-boot/master, thanks!
> >>
> >> -- 
> >> Tom
> > 
> >  Hello,
> > 
> >  This appears to break beaglebone black support, reverting this commit
> > make u-boot works again.
> 
> hmm..I see the problem. Here we are hard coding MPU freq to 1GHz even
> efuse say it is not supported(I am not sure why this is being done, may
> be Tom can give more details). Even in kernel I see that cpufreq is
> reading efuse to determine mpu frequency. Now that we have jitter
> optimized pll configurations, looks like unsupported freq is causing an
> issue. Can you see if the below patch helps?

Well, in the kernel, did anyone poke the Beagleboard folks about this,
before pushing the change?  There's BBB shipping with chips that did not
have their efuses set, hence the way things were structured in U-Boot.

-- 
Tom
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