After running the Fedora installer, many DTBs are present in e.g. /boot/dtb-3.16.0-0.rc0.git11.1.fc21.armv7hl+lpae/. However, no DTBs for Tegra boards are present. tegra124-jetson-tk1.dtb is one example that's missing. The missing DTBs are evidently built by the kernel build process, since they do show up at: http://mirror.pnl.gov/fedora/linux/development/rawhide/armhfp/os/images/pxeboot/dtb/
On IRC, dgilmore says this is probably because Tegra support isn't enabled in the LPAE kernel build. I installed on Jetson TK1, and the CPU on that board does support LPAE, so an LPAE kernel was installed.
Yes, so to date we've not enabled tegra in the LPAE kernel as there's not been devices widely available to test and use.
Is fixing this simply a matter of moving some kernel defconfig options from the non-LPAE Fedora defconfig to some defconfig that's shared between LPAE and non-LPAE?
Created attachment 924300 [details] Patch to kernel fedpkg that fixes this I believe this should fix it. I'm going to build it overnight and test it tomorrow. It at least passes the "listnewconfig" check...
(In reply to Stephen Warren from comment #3) > Is fixing this simply a matter of moving some kernel defconfig options from > the non-LPAE Fedora defconfig to some defconfig that's shared between LPAE > and non-LPAE? Mostly but to date I've not seen the point in supporting it because there's not really any devices I see that will benefit from LPAE as all the devices have < 4Gb of RAM.
Re: comment 5: The reason it's useful for the LPAE kernel to support Tegra is that the installer installs the LPAE kernel on any system with an LPAE capable CPU, even if the RAM size doesn't make LPAE actually useful. There are 5 Tegra boards supported by the mainstream kernel that contain CPUs that support LPAE, albeit admittedly only 1 (Jetson TK1) is going to be widely available and useful for generic distros.
Uggh. My build failed due to lack of disk space. I'll try building on an attached USB HDD tonight and see if that works out...
It's no issues, I'll sort it out and push it in the next few days
With the patch applied, the non-LPAE kernel appears to work fine. The LPAE kernel boots OK on Tegra, but there's obviously some missing regulator module, since a bunch of regulators don't probe, and hence HDMI doesn't work. I'll track down the missing option and move it into config-armv7 to fix this.
OK, the patch I'm going to use isn't quite what you have. Give me a day or so and I'll have it in place, I'm @ Flock ATM
Out of curiosity, what's the benefit of not using the patch I've already spent time on preparing?
FWIW, the problem with the armv7hl+lpae build with my patch is that the AS3722 PMIC drivers aren't enabled, evee though config-armv7-generic enables/requests it. That's because MFD_AS3722 depends on I2C=y (not just I2C). Fedora has I2C=m in config-generic. Various things enabled in config-armv7 select I2C (so force it to =y not =m), such as OMAP2PLUS support, and numerous others. Since none of those things are enabled in the LPAE config, this doesn't happen, so I2C=m, which ends up disabling MFD_AS3772, so most regulators don't exist at runtime, and anything relying on them fails, such as HDMI. I'd suggest that kernel.spec go through all the final generated configs/* files and double-check that the "make oldnoconfig" didn't remove any options. I could try coding that up if you want.
Tegra will be in both lpae and general kernel with 3.17rc2
Committed to F-21 and rawhide.
kernel-3.16.2-300.fc21 has been submitted as an update for Fedora 21. https://admin.fedoraproject.org/updates/kernel-3.16.2-300.fc21
I've validated that the desired DTBs appear in /boot/dtb-* in the rawhide kernels. Thanks.
kernel-3.16.2-300.fc21 has been pushed to the Fedora 21 stable repository. If problems still persist, please make note of it in this bug report.