Hi.
I've been poking a problem on an ipq6018 board I have. Specifically it
pertains to the address range for GPIO # 20, touching any address in the
range 0x14000 - 0x14FFC results in data-abort.
I initially encountered this with the upstream kernel here:
https://paste.debian.net/1225390/
and assumed that I was doing something wrong, so went hunting for
evidence that the downstream kernel touched the registers in that range,
my assumption that something extra was happening the downstream kernel
to make the register read kosher, turned out to be wrong, assuming
something like the transition from arm32 to arm64 or a trustzone setting
getting in the way.
Downstream doesn't touch that register with the default drivers and
shipping DTS files.
Modifying the downstream kernel to do a simple read of each ctrl_reg
makes downstream choke on the address too.
This is the only bootable version of the downstream kernel reading every
ctrl_reg in the range of gpio0 - gpio79 - skipping gpio20 since even
downstream the address range 0x14000 - 0x14FFC is broken.
In other words I can prove the problem is only with the physical range
0x01014000 - 0x01014FFC
gpio19 @ 01013000 - 01013FFC is fine
gpio21 @ 01015000 - 01015FFC is fine
the issue is limited to gpio20 @ 0x01014000 - 0x01014FFC
Downstream kernel:
https://paste.debian.net/1225388/
This is also the case when doing a dumb dump in u-boot
Stock u-boot:
https://paste.debian.net/1225389/
https://paste.debian.net/1225396/
Is there a sku of this SoC which perhaps reserves 0x14000 - 0x14FFC or a
version of the firmware that does so ?
I've already discussed this offline with Baruch who suggested firmware
versions based on previous feedback working with this part, however the
firmware version on the board is newer than what was suggested here
https://lore.kernel.org/all/5ba36dcd7c50b640e0bdaf5b9c2248f3@xxxxxxxxxxxxxx/
"Please try with TZ version >= TZ.WNS.5.1-00084."
admin@OpenWrt:~$ cat /proc/device-tree/tz_version
CRM-TZ.WNS.5.1-00113
admin@OpenWrt:~$ cat /proc/device-tree/tz_version
CRM-TZ.WNS.5.1-00113
admin@OpenWrt:~$ cat /proc/device-tree/rpm_version
CRM-RPM.BF.2.4.1-00089
admin@OpenWrt:~$ cat /proc/device-tree/boot_version
crm-ubuntu47-BOOT.XF.0.3-00090-IPQ60xxLZB-2
I'm not far off writing a patch based on a "compatible" string to mark
gpio # 20 as bad - any other ideas or insights welcome though.
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bod
