[Orange Pi PC] Testers needed for DRAM reliability tests

bronco

Hi,

currently the linux-sunxi devs are trying to provide mainline kernel/u-boot support for Orange Pi PC (which is great news, I tested USB performance yesterday and with mainline kernel and being able to benefit from UASP this is ~40 MB/s -- a lot faster than what we get today with 3.4.39).

This is not only about writing support for the hardware from scratch (you can't rely on the crappy 3.4.39 kernel code we've currently to use) but also check the hardware reliability limits.

Since the Orange Pi manufacturer doesn't care that much about reliability but the linux-sunxi devs have to, they're currently evaluating how high DRAM can be clocked safely:

http://linux-sunxi.org/Orange_Pi_PC#DRAM_clock_speed_limit
https://groups.google.com/d/msg/ ... 4k8nIE/FUn7cks3AwAJ

And this is where they need your help! If you've a 2nd linux box (can be an SBC as well) and are able to build the sunxi-tools (most recent version needed for sunxi-fel) the whole thing is pretty straightforward and outlined here: https://github.com/ssvb/lima-memtester/releases/latest

Just connect the OPi PC without inserted SD card to the machine where lima-memtester is running using an USB-to-micro-USB cable and start with the highest settings available. The test will either stop really fast (no blinking green LED any more) or after a certain amount of time the 2nd LED will light constantly (test passed).

On a connected display you'll see a spinning cube unless the OPi PC crashes (using Mali/GPU stressing memory bandwidth). In case you find a working MHz setting it would be good to repeat the test and let it run overnight to verify stability. And then please report back either here or by creating a linux-sunxi account and contributing directly to the wiki.

Thx

nematocyst

How would I do this on an Orange Pi Plus?  Or would that even help?

I'd like to do this anyway just to find reliable memory settings.  Everything seems fine, but that isn't necessarily a good data point.  Problem with the plus is just that it boots from eMMC absent an SD card.

bronco

nematocyst replied at 2015-12-16 23:47
How would I do this on an Orange Pi Plus?  Or would that even help?

I'd like to do this anyway just ...

Of course it helps for the Plus too even if results are not directly transferable to the PC since other DRAM chips might be soldered or different routing to the chips.

On the Plus you've to choose "FEL mode" manually: http://linux-sunxi.org/Xunlong_Orange_Pi_Plus#FEL_mode (the linux-sunxi wiki is the only relevant information source for all Allwinner based SoCs )

bronco

C'mon guys, what's up? We still need your help determining reliable DRAM clockspeeds: http://linux-sunxi.org/Orange_Pi_PC#DRAM_clock_speed_limit

fritz

On Orange pi plus with V3:
sudo ./fel-boot-lima-memtester-on-orange-pi-pc 768
OK!

sudo ./fel-boot-lima-memtester-on-orange-pi-pc 792

Stack pointers: sp_irq=0x00002000, sp=0x00005E08
MMU is not enabled by BROM
Generating the new MMU translation table at 0x00044000
=> Executing the SPL... done.
libusb usb_bulk_send error -9

It does not load at all.

runnerway

bronco replied at 2015-12-22 22:53
C'mon guys, what's up? We still need your help determining reliable DRAM clockspeeds: http://linux-s ...

I did it this morning.
It's nice when we can help.

User:Runnerway's Orange Pi PC

fel-boot-lima-memtester-on-orange-pi-pc-v3.tar.gz

672 MHz

696 MHz

Small heatsink.

lymon

OPI-PC:

672: OK (red led on and let it run for another 4 hours)
696: fails/hangs after approx. 10 minutes

hojnikb

I suppose ~667Mhz should be stable, since thats what DRAM is rated for...

dvl36

You mean H3 DRAM controller, right? (OPI PC DRAM rated for 800Mhz, DDR3-1600).

hojnikb

dvl36 replied at 2015-12-26 04:26
You mean H3 DRAM controller, right? (OPI PC DRAM rated for 800Mhz, DDR3-1600).

You're right, ram is actually 1600MT.
But issue is probably dram controller not capable of  such speeds.