James Kingdon Posted July 1, 2017 Posted July 1, 2017 Hi. My dtb skills seem to be lacking, so I'm seeking guidance I'm running Armbian 5.27 from the sd card, kernel is 4.9.20-26 after an Apr 10 update. /boot has the following dtbs: -rw-r--r-- 1 root root 60782 Apr 10 21:29 exynos5422-odroidxu3.dtb -rw-r--r-- 1 root root 60031 Apr 10 21:29 exynos5422-odroidxu3-lite.dtb -rw-r--r-- 1 root root 60936 Jul 1 12:55 exynos5422-odroidxu4.dtb I want to change the fan threshold settings and pwm values to try and get more aggressive cooling as I'm not quite staying out of thermal throttling. After converting exynos5422-odroidxu4.dtb with dtc it's easy to see where both the thresholds and pwm values are set, so I edited to taste, recompiled the dts -> dtb and rebooted. And, absolutely nothing changed. I'm guessing I either have the wrong dtb (maybe it's using the xu3 version?) or maybe it's not using any of the dtbs in /boot? How do I confirm what's going on? One possible source of confusion - I have the emmc plugged in with the original hardkernel software on it, so I guess there exists the small possibility that something is getting picked up from there. I guess I'll try making the changes to the xu3 file and see what happens, but I'd like to understand how this fits together a little better.
Xalius Posted July 1, 2017 Posted July 1, 2017 Can you post the decompiled dts to pastebin? There is a representation of the dtb the kernel has loaded in the /sys/... filesystem where you can browse it like directory and files.
James Kingdon Posted July 1, 2017 Author Posted July 1, 2017 Ah, it looks like the config appends the dtb to the kernel, so the files I'm editing are likely not being used: CONFIG_ARM_APPENDED_DTB=y Looks like I need to recompile the kernel. Thanks for the pointer to /sys/firmware/devicetree. Sadly most of the data in pwm-fan reads as binary, making it a little inconvenient to work with.
zador.blood.stained Posted July 1, 2017 Posted July 1, 2017 2 minutes ago, James Kingdon said: CONFIG_ARM_APPENDED_DTB=y This only allows the kernel to look for appended DTB. You can check the boot script to see if DT is loaded from the filesystem.
James Kingdon Posted July 1, 2017 Author Posted July 1, 2017 Excellent - where do I find the boot script?
zador.blood.stained Posted July 1, 2017 Posted July 1, 2017 2 minutes ago, James Kingdon said: Excellent - where do I find the boot script? /boot/boot.ini or /boot/boot.cmd
James Kingdon Posted July 1, 2017 Author Posted July 1, 2017 Interesting, no boot.* files in /boot as seen on the running filesystem. Currently /boot contains -rw-r--r-- 1 root root 140214 Mar 28 07:13 config-4.9.13-19 -rw-r--r-- 1 root root 140214 Apr 3 16:29 config-4.9.20-21 -rw-r--r-- 1 root root 140251 Apr 10 20:40 config-4.9.20-26 lrwxrwxrwx 1 root root 32 Jul 1 17:15 exynos5422-odroidxu3.dtb -> tmp/exynos5422-odroidxu3-jbk.dts -rw-r--r-- 1 root root 60782 Apr 10 21:29 exynos5422-odroidxu3.dtb_orig -rw-r--r-- 1 root root 60031 Apr 10 21:29 exynos5422-odroidxu3-lite.dtb -rw-r--r-- 1 root root 60936 Jul 1 12:55 exynos5422-odroidxu4.dtb -rw-r--r-- 1 root root 60936 Jul 1 12:54 exynos5422-odroidxu4.dtb_orig -rw-r--r-- 1 root root 7662780 Feb 22 05:51 initrd.img-3.10.96+ -rw-r--r-- 1 root root 9395964 Mar 30 22:08 initrd.img-4.9.13-19 -rw-r--r-- 1 root root 9395397 Apr 5 20:46 initrd.img-4.9.20-21 -rw-r--r-- 1 root root 5443110 May 2 20:50 initrd.img-4.9.20-26 -rw------- 1 root root 2081916 Mar 28 08:00 System.map-4.9.13-19 -rw------- 1 root root 2082296 Apr 3 17:19 System.map-4.9.20-21 -rw------- 1 root root 2083024 Apr 10 21:27 System.map-4.9.20-26 drwxr-xr-x 3 root root 4096 Jul 1 17:56 tmp -rw-r--r-- 1 root root 9444217 Oct 9 2016 uInitrd-3.10.103-123 -rw-r--r-- 1 root root 9444044 Oct 11 2016 uInitrd-3.10.103-124 -rw-r--r-- 1 root root 9618690 Feb 22 05:50 uInitrd-3.10.104-132 -rw-r--r-- 1 root root 8357696 Jul 6 2016 uInitrd-3.10.96-110 -rw-r--r-- 1 root root 8361957 Jul 6 2016 uInitrd-3.10.96-113 -rw-r--r-- 1 root root 8361406 Jul 6 2016 uInitrd-3.10.96-114 -rw-r--r-- 1 root root 7878131 Feb 22 06:54 uInitrd-4.9.11-8 -rw-r--r-- 1 root root 9396028 Mar 30 22:09 uInitrd-4.9.13-19 -rw-r--r-- 1 root root 9395461 Apr 5 20:46 uInitrd-4.9.20-21 -rw-r--r-- 1 root root 9395241 Apr 14 19:59 uInitrd-4.9.20-26 -rw------- 1 root root 4551112 Feb 22 03:21 vmlinuz-4.9.11-8 -rw------- 1 root root 4790304 Mar 28 08:00 vmlinuz-4.9.13-19 -rw------- 1 root root 4791080 Apr 3 17:19 vmlinuz-4.9.20-21 -rw------- 1 root root 4793000 Apr 10 21:27 vmlinuz-4.9.20-26
James Kingdon Posted July 2, 2017 Author Posted July 2, 2017 Well there's one mistake for starters - I've linked the xu3 dtb to my dts source file. I'll get that fixed...
James Kingdon Posted July 2, 2017 Author Posted July 2, 2017 OK, so I appear to have caused myself a lot of confusion by having both the emmc and the sd card installed all the time, both with linux installed, and both apparently having 'partitions' labelled boot containing dtb files (and kernels etc). I'm guessing the boot partition on the sd card was supposed to have been mounted on /boot, but for some reason wasn't. Life is looking a little simpler now that I've unplugged the emmc. Update: Rational behaviour has been restored. The *xu4.dtb in the boot partition of the sd-card is live and the changes to the trigger temperatures and pwm values have taken affect. The heatsink/fan combo I'm using at the moment isn't up to the job, but at least I can control what's happening. Now can I keep things straight if I put the emmc back again... Incidentally, what is the 'normal' setup, should the boot partition be mounted during normal operation?
Igor Posted July 3, 2017 Posted July 3, 2017 On 2. 7. 2017 at 2:47 AM, James Kingdon said: Incidentally, what is the 'normal' setup, should the boot partition be mounted during normal operation? (recent) Normal setup is one ext4 partition, while there is currently a problem with eMMC install which need an manual u-boot update first. I am still working on a u-boot update from Linux script. Currently you only can update it from within u-boot. This doesn't looks like our install. Probably you have SD card and eMMC with stock hardkernel Ubuntu ... attached at once and this can looks weirdo, especially if you did some manual adjustments on your own.
James Kingdon Posted July 3, 2017 Author Posted July 3, 2017 5 hours ago, Igor said: (recent) Normal setup is one ext4 partition, while there is currently a problem with eMMC install which need an manual u-boot update first. I am still working on a u-boot update from Linux script. Currently you only can update it from within u-boot. This doesn't looks like our install. Probably you have SD card and eMMC with stock hardkernel Ubuntu ... attached at once and this can looks weirdo, especially if you did some manual adjustments on your own. Yes, "SD card and eMMC with stock hardkernel Ubuntu ... attached at once" was exactly my situation, and it's quite likely I changed something along the way too. I'll put grabbing a fresh image and doing a clean install on my todo list Thanks for your work on this board, it's a good performer even if it is difficult to pull the heat out of that soc. I'm guessing it's a PoP layout with the memory on top insulating the cpu.
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