On wto, 2014-11-25 at 09:47 +0100, Krzysztof Kozlowski wrote:

On pon, 2014-11-24 at 19:20 -0800, Kevin Hilman wrote:

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On Mon, Nov 24, 2014 at 5:50 PM, Kukjin Kim [off-list ref] wrote:

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Olof Johansson wrote:

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On Mon, Nov 24, 2014 at 5:37 PM, Olof Johansson [off-list ref] wrote:

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On Mon, Nov 24, 2014 at 5:35 PM, Kevin Hilman [off-list ref] wrote:

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On Mon, Nov 24, 2014 at 4:25 PM, Olof Johansson [off-list ref] wrote:

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On Mon, Nov 24, 2014 at 11:51 AM, Kevin Hilman [off-list ref] wrote:

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Is anyone at Samsung actually looking into these MCPM issues?

Hi Kevin,

What hardware are you having problems with? 5420 or 5422/5800?

Yes.  :)

exynos5420-arndale-octa:
http://storage.armcloud.us/kernel-ci/mainline/v3.18-rc6/arm-exynos_defconfig/boot-exynos5420-

arndale-octa.html

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exynos5422-odroid-xu3:
http://storage.armcloud.us/kernel-ci/mainline/v3.18-rc6/arm-exynos_defconfig/boot-exynos5422-

odroid-xu3.html

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My boot tests seem to pass fine because I have such a minimal
userspace, but Tyler Baker reported that with a "real" userspace, he
can't boot to a shell:

  http://lists.infradead.org/pipermail/linux-arm-kernel/2014-September/286203.html

Hmm...his report was in Sep...I think it should be fine with current -next?

No, it is still broken in linux-next (as I stated above.)

Moreover, earlier in this thread you mentioned you were merging some
MCPM patches that should address this, but did not respond when I
asked which patches you thing should address this issue

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To be honest, since I don't have the exynos5420 arndale, chromebook...but smdk
which has different bootloader, I couldn't test it...I'll try to make a test
farm like you guys...

Do you have some colleagues with any other 542x hardware?  I had
assumed that linux-next was being better tested on the publicaly
available, and widely available boards like odroid-xu3 and
Chromebook2, but I've come to realize the hard way that that is not
the case.  You mention your board has a different bootloader.  Do you
suspect there's a bootloader issue on these other platforms?  If so,
could you elaborate on possible fixes?  I'm more than willing to test
any proposed fixes, but I'm not familiar enough yet with these SoCs to
figure out the underlying issues alone.

Until you have a working board farm, you could start having a closer
look at the boot logs we're already producing.  Admittedly linux-next
broken in many ways besides this one for exynos currently, but it has
been having these imprecise aborts well before the other recent
issues.

Also, It's very possible that this issue is not even MCPM related at
all, and MCPM is just uncovering a previously hidden bug.  It would be
very helpful if people more familiar with this hardware and SoC would
investigate bug reports like these.

Interesting thing can be found in exynos5420.dtsi:
mdma1: mdma at 11C10000 {
	...
	/*
	 * MDMA1 can support both secure and non-secure
	 * AXI transactions. When this is enabled in the kernel
	 * for boards that run in secure mode, we are getting
	 * imprecise external aborts causing the kernel to oops.
	 */
	status = "disabled";
};

I am booting Arndale Octa on some other config and exynos. However with
or without MCPM the imprecise aborts are still present (but not fatal,
shell comes up).

My board boots also under secure firmware (I am using Linaro's ubuntu
image). Maybe that is the cause?

One update: some fatal imprecise aborts (hanging boot) happen also on
exynos_defconfig without MCPM. It looks random... one boot fails, next
succeeds (however also with "imprecise external abort" message but shell
comes up).

Best regards,
Krzysztof