PROCESSOR-SDK-AM62X: Default PRU fw image doesn't work - invalid resource table.

P Young

Tool/software:

Hi!

I'm working with Variscite's am62x som & it's PRU. I'm using the kernel on the SD card that it was shipped with.

I'm trying to see the basic PRU example working. I'm greeted with the following debug message:

root@am62x-var-som:~# echo start > /sys/class/remoteproc/remoteproc2/state
[ 178.729240] remoteproc remoteproc2: powering up 30074000.pru
[ 178.740398] remoteproc remoteproc2: Booting fw image am62x-pru0-fw, size 81344
[ 178.747778] remoteproc remoteproc2: invalid resource table: forced to NULL
[ 178.755124] remoteproc remoteproc2: remote processor 30074000.pru is now up
Sanity-checks below:

root@am62x-var-som:~# uname -a
Linux am62x-var-som 6.1.83-ti-g055ead3d5359 #1 SMP PREEMPT Mon Oct 28 14:56:49 UTC 2024 aarch64 aarch64 aarch64 GNU/Linux

root@am62x-var-som:~# ls -l /sys/class/remoteproc/
total 0
lrwxrwxrwx 1 root root 0 Jan 1 00:00 remoteproc0 -> ../../devices/platform/bus@f0000/bus@f0000:bus@4000000/5000000.m4fss/remote0
lrwxrwxrwx 1 root root 0 Jan 1 00:00 remoteproc1 -> ../../devices/platform/bus@f0000/bus@f0000:bus@b00000/bus@f0000:bus@b00000:1
lrwxrwxrwx 1 root root 0 Jan 1 00:00 remoteproc2 -> ../../devices/platform/bus@f0000/30040000.pruss/30074000.pru/remoteproc/rem2
lrwxrwxrwx 1 root root 0 Jan 1 00:00 remoteproc3 -> ../../devices/platform/bus@f0000/30040000.pruss/30078000.pru/remoteproc/rem3

root@am62x-var-som:~# lsmod | grep pru
irq_pruss_intc         16384 0
pru_rproc              24576 0
pruss                  16384 1 pru_rproc

root@am62x-var-som:~# cat /sys/class/remoteproc/remoteproc2/firmware
am62x-pru0-fw

root@am62x-var-som:~# ls -l /lib/firmware/
total 10792
-rw-r--r-- 1 root root    4178 Mar 9 2018 LICENCE.broadcom_bcm43xx
-rw-r--r-- 1 root root    8914 Mar 9 2018 LICENCE.cypress
lrwxrwxrwx 1 root root      68 Mar 9 2018 am62-main-r5f0_0-fw -> /lib/firmware/ti-ipc/am62xx/ipc_echo_test_mcu2_0_release_strif
lrwxrwxrwx 1 root root      75 Mar 9 2018 am62-main-r5f0_0-fw-sec -> /lib/firmware/ti-ipc/am62xx/ipc_echo_test_mcu2_0_release_d
lrwxrwxrwx 1 root root      68 Mar 9 2018 am62-mcu-m4f0_0-fw -> /lib/firmware/ti-ipc/am62xx/ipc_echo_test_mcu2_0_release_stripf
lrwxrwxrwx 1 root root      75 Mar 9 2018 am62-mcu-m4f0_0-fw-sec -> /lib/firmware/ti-ipc/am62xx/ipc_echo_test_mcu2_0_release_sd
lrwxrwxrwx 1 root root      47 Mar 9 2018 am62x-pru0-fw -> /lib/firmware/pru/PRU_RPMsg_Echo_Interrupt0.out
lrwxrwxrwx 1 root root      47 Mar 9 2018 am62x-pru1-fw -> /lib/firmware/pru/PRU_RPMsg_Echo_Interrupt1.out
-rw-r--r-- 1 root root 478552 Mar 9 2018 bl32.bin
-rw-r--r-- 1 root root 4320000 Mar 9 2018 bl32.elf
drwxr-xr-x 2 root root    4096 Mar 9 2018 brcm
drwxr-xr-x 2 root root    4096 Mar 9 2018 cypress
drwxr-xr-x 2 root root    4096 Mar 9 2018 pru
-rw-r--r-- 1 root root    4896 Mar 9 2018 regulatory.db
-rw-r--r-- 1 root root    1085 Mar 9 2018 regulatory.db.p7s
-rw-r--r-- 1 root root 126976 Mar 9 2018 rgx.fw.33.15.11.3
-rw-r--r-- 1 root root 126976 Mar 9 2018 rgx.fw.33.15.11.3.64k
-rw-r--r-- 1 root root 387960 Mar 9 2018 rgx.sh.33.15.11.3
-rw-r--r-- 1 root root      28 Mar 9 2018 tee-header_v2.bin
-rw-r--r-- 1 root root       0 Mar 9 2018 tee-pageable_v2.bin
-rw-r--r-- 1 root root 478552 Mar 9 2018 tee-pager_v2.bin
-rw-r--r-- 1 root root 478552 Mar 9 2018 tee-raw.bin
-rw-r--r-- 1 root root 478580 Mar 9 2018 tee.bin
-rw-r--r-- 1 root root 4320000 Mar 9 2018 tee.elf
drwxr-xr-x 3 root root    4096 Mar 9 2018 ti-ipc

root@am62x-var-som:~# dmesg | grep remoteproc [ 6.190854] k3-m4-rproc 5000000.m4fss: configured M4 for remoteproc mode [ 6.213952] remoteproc remoteproc0: 5000000.m4fss is available [ 6.225414] remoteproc remoteproc0: powering up 5000000.m4fss [ 6.234374] remoteproc remoteproc0: Booting fw image am62-mcu-m4f0_0-fw, size 54860 [ 6.273679] remoteproc remoteproc0: remote processor 5000000.m4fss is now up [ 6.475541] remoteproc remoteproc1: 78000000.r5f is available [ 6.489070] remoteproc remoteproc1: attaching to 78000000.r5f [ 6.540836] remoteproc remoteproc1: remote processor 78000000.r5f is now attached [ 7.528869] remoteproc remoteproc2: 30074000.pru is available [ 7.536289] remoteproc remoteproc3: 30078000.pru is available [ 178.729240] remoteproc remoteproc2: powering up 30074000.pru [ 178.740398] remoteproc remoteproc2: Booting fw image am62x-pru0-fw, size 81344 [ 178.747778] remoteproc remoteproc2: invalid resource table: forced to NULL [ 178.755124] remoteproc remoteproc2: remote processor 30074000.pru is now up

5 months ago

0 Nick Saulnier 5 months ago

TI__Guru** 100820 points

Hello,

First off, please note that I can only comment on TI hardware and TI software. So I will not be able to comment directly on the Variscite SOM hardware, or whatever PRU binaries they prepackage within the filesystem that is provided alongside that SOM.

I will be linking to the documentation for AM62x Linux SDK 9.2.1.10, since that is the latest TI Linux SDK that uses Linux kernel 6.1.

Getting started resources

As you are getting started with the PRU cores, please use the PRU Getting Started Labs:
https://software-dl.ti.com/processor-sdk-linux/esd/AM62X/09_02_01_10/exports/docs/linux/Foundational_Components/PRU-ICSS-Training.html

I am the author of those labs. Additionally, the broader team and I will be working to rewrite those labs and add a bunch of additional content into a PRU module for the AM62x academy later this year: https://dev.ti.com/tirex/explore/node?node=A__AEIJm0rwIeU.2P1OBWwlaA__AM62-ACADEMY__uiYMDcq__LATEST

So if you have any feedback or questions, please create a separate e2e thread to discuss. I can help there, and integrate any feedback you have into the upcoming PRU academy.

So... what might be going on with the resource table?

You can find more information about resource tables here:
https://software-dl.ti.com/processor-sdk-linux/esd/AM62X/09_02_01_10/exports/docs/common/PRU-ICSS/Resource_Tables.html

Since I don't know what firmware binary Variscite packaged into their filesystem, I would probably suggest downloading the PRU software support package (PSSP), rebuilding the AM62x PRU IPC Echo example, and booting the binary that you built. Please use the latest version of the PSSP (6.4). It looks like the RPMsg library in PSSP v6.1 (when I added AM62x support) is incompatible with the Linux drivers in kernel 6.1 and later, so the PSSP version needs to be 6.2 at minimum:
https://git.ti.com/cgit/pru-software-support-package/pru-software-support-package/tag/?h=v6.2.0

https://git.ti.com/cgit/pru-software-support-package/pru-software-support-package is PSSP link

RPMsg Echo Interrupt examples are here:
https://git.ti.com/cgit/pru-software-support-package/pru-software-support-package/tree/examples/am62x

Regards,

Nick

0 P Young 5 months ago in reply to Nick Saulnier

Prodigy 40 points

Thanks Nick!

Quick sanity check, my build environment is Yocto based. My PRU firmware is getting compiled & installed using the recipe found at:
meta-ti/meta-ti-extras/recipes-bsp/pru/pru-icss_git.bb

Said recipe looks to be using the same git repo for the PSSP as you said above (although it was using 6.3.0, have updated it to use 6.4.0):

BRANCH = "master"
SRC_URI = "git://git.ti.com/git/pru-software-support-package/pru-software-support-package.git;protocol=https;branch=${BRANCH}"
SRCREV = "f3e3996c50b2c7bc7ed1f6f5374f3d8efb501a45"
PV = "6.4.0"

The results of the installs look sound to me, e.g. PRU firmwares are getting compiled & installed into the right locations on the rootfs plus it looks from dmesg that the PRUs are getting probed by remoteproc ok.

I found your comment regarding "RPMsg library in PSSP v6.1 (when I added AM62x support) is incompatible with the Linux drivers in kernel 6.1" very enlightening but am I wrong in thinking that as my recipe was using 6.3 this isn't relevant?

0 Nick Saulnier 5 months ago in reply to P Young

TI__Guru** 100820 points

You are correct, v6.3 vs v6.4 should not make a difference. I cannot comment on the yocto build flow, I typically just build the examples on my computer.

You can find the steps I like to use to test PRU RPMsg here:
https://e2e.ti.com/support/processors-group/processors/f/processors-forum/1487606/processor-sdk-am62x-linux-arm-to-pru-rpmsg-communication/5713282#5713282

Regards,

Nick

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PROCESSOR-SDK-AM62X: Default PRU fw image doesn't work - invalid resource table.