[U-Boot] [PATCH 3/8] boottime: Add core boottime measurement support

[Simon Glass]

Hi Lee,

On Mon, Nov 26, 2012 at 1:00 AM, Lee Jones <lee.jones at linaro.org> wrote:
> Hi Simon,
>
>> On Tue, Nov 20, 2012 at 6:33 AM, Lee Jones <lee.jones at linaro.org> wrote:
>> > Boottime is a tool which can be used for full system booting time
>> > measurement. Bootloader boot time is passed to the kernel component
>> > though ATAGS. The kernel-side driver then uses this information to
>> > provide full system boot time diagnostics though debugfs.
>> >
>> > Based heavily on the original driver by Jonas Aaberg.
>> >
>> > Signed-off-by: Lee Jones <lee.jones at linaro.org>
>>
>> Did you take a look at bootstage, which seems at least on the surface
>> to provide a similar mechanism? This passes the information to the
>> kernel through a device tree, or worse case a 'stash area'.
>
> I didn't see this before.
>
> I don't see the kernel counterpart, did it make it upstream?

It was sent upstream, just for a feeler, but before U-Boot support was
mainlined and before we had a way to deal with the non-fdt case. That
is now implemented and in mainline, although it has not yet gone out
in a release (should be Jan 2013). So I was planning to address that
again in the kernel at some point.

>
> Wolfgang, didn't you know about bootstage? This could have saved
> us a great deal of time.
>
> Kind regards,
> Lee
>
> --
> Lee Jones
> Linaro ST-Ericsson Landing Team Lead
> Linaro.org │ Open source software for ARM SoCs
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Regards,
Simon