07:21 <jernej> apritzel: I compared OPi zero2 DRAM configuration between BSP and mainline and it matches completely (minus calibration/training values, which are similar.)

07:22 <jernej> so no bug there, at least on my side

07:23 <jernej> I still think BROM might initialize something differently in case of FEL and SD boot

07:26 <smaeul> did you compare clocks and PRCM?

07:28 <jernej> no

07:30 <jernej> but I just noticed that while write and read training factors are indeed similar, they are almost consistent between runs of same type. I'll look into that procedures again

07:30 <jernej> I'll look into clocks and PRCM afterwards

07:30 <smaeul> I don't remember there being any code in BROM that would affect DRAM directly, only indierct things like bus clocks

07:34 <jernej> smaeul: I noticed that H6 and H616 PLL init code in boot0 binary first clears and then sets bit 0 in PRCM reg 0x310

07:34 <jernej> we don't do that

07:35 <jernej> do you have any idea what is function of this register?

07:35 <smaeul> yes, that's some analog circuit calibration procedure

07:35 <jernej> ok, so this could be important

07:36 <smaeul> https://lore.kernel.org/u-boot/28efdf36-e1a3-6acd-c18e-2d68eca13aaf@sholland.org/

07:36 <jernej> ah, and bit 2 is set too

13:57 <jernej> smaeul: I compared H6 PRCM settings between boot0 and SPL and I noticed that register 0x07010244 is set. BSP U-Boot sources say it's PLL LDO configuration but all my attempts to set it failed.

13:57 <jernej> do you know if this register is somehow locked?

13:58 <jernej> maybe I just failed to program key correctly...

14:04 <jernej> ah, scratch that. it's configured properly. it's just that TF-A probably protects this region, so reading it returns all zeros.

14:05 <jernej> on images with BSP stack it's freely accessible

16:18 <smaeul> jernej: right, TF-A protects the PLL registers. You can set this to 7 (or write it at runtime) to access them from NS world: https://github.com/ARM-software/arm-trusted-firmware/blob/master/plat/allwinner/common/sunxi_security.c#L36