Hi Simon,
Simon Glass sjg@chromium.org writes:
On 8 December 2014 at 10:58, Kevin Hilman khilman@kernel.org wrote:
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FWIW, the XU3 firmware is broken in other ways as well which have a major impact on power management.
First, with mainline kernels using MCPM, only 6 of 8 CPUs come online. However, even with that fixed[1], it turns out that the kernel can't properly manage CCI due to secure firmware[2], which means that MCPM (multi-cluster power management) can't work, and thus the low-power cluster-idle states can't work, the big.LITTLE switcher cannot work, and the ongoing work on energy-aware scheduling will not be useful on this platform.
Anyone know what are the chances of getting a non-secure version of the firmware for this platform. The Samsung Chromebook2 with basically the same SoC (5800 compared to the 5422 on the XU3) ships with non-secure firmware so all of the above mentioned features are working just fine.
I have pushed on this but apparently it is not possible - they need to sign every BL2. The only implementation I've seen sets up the chip in BL2 (U-Boot SPL) so I don't think we can work around it.
Not quite sure I'm following...
So is secure-mode enabled before BL2 is started? Or do you mean BL2 is where secure-mode is enabled? If it's done in BL2, and if the hardkernel folks are willing to sign BL2 images (which I gathered from discussions elsewhere in this series) then it seems possible to turn off secure-mode.
So I went to look in the u-boot-samsung repo and didn't see the code for the SPL there. Is the BL2 source (which I understood to be u-boot SPL) in some other repo?
It takes us back to the 1960s where we sent off our code at night to run it :-)
I think the best bet is the current effort to mainline the rest of the Chromebook code then try to build it for XU3.
What's the status of that effort?
I'm working on getting these same features working on the XU3, but this broken firmware as brought a halt to any real progress.
Agreed, but I think this is feasible once U-Boot on XU3 is sorted out.
Let's hope so.
Kevin