[meta-xilinx] ZC706 - Device tree blobs

[Nathan Rossi]

> -----Original Message-----
> From: meta-xilinx-bounces at yoctoproject.org [mailto:meta-xilinx-
> bounces at yoctoproject.org] On Behalf Of Stephen Mossom
> Sent: Friday, September 19, 2014 10:42 PM
> To: meta-xilinx at yoctoproject.org
> Subject: [meta-xilinx] ZC706 - Device tree blobs
> 
> Hi All
> 
> 
> 
> I am building a Linux system for the ZC706 using the meta-xilinx layer
> daisy branch.
> 
> 
> 
> I can boot my board using the resulting kernel , rootfs and dtb but I get
> some errors during the boot process.
> 
> 
> 
> For example:-
> 
> 
> 
> hwclock: can't open '/dev/misc/rtc': No such file or directory

The device tree in meta-xilinx only has the bindings for the older i2c driver. I have since updated it and added the newer bindings.

> 
> 
> 
> dma-pl330: probe of f8003000.ps7-dma failed with error -16

This error can be ignored, there are two register sets of the pl330, one for secure mode and one for non-secure. As long as one is probed it will function and the other will fail to probe.
It was left in the meta-xilinx device tree for completeness, however I have commented one of the nodes for the pl330 out for now.

I have updated the device trees in meta-xilinx, and back ported them to daisy.

Regards,
Nathan

> 
> 
> 
> I downloaded the Xilinx release images for the ZC706 2014.2 and booted
> them as a comparison. I don't see the same errors. The rtc initialises OK
> as does the pl330 driver.
> 
> 
> 
> I compared the log from the good boot (Xilinx release images) to the boot
> with errors (meta-xilinx build) and noticed that the i2c doesn't seem to
> be initialising properly on the meta-xilinx build which explains why the
> real time clock isn't initialised.
> 
> 
> 
> I downloaded petalinux which is used to generate the release images and
> compared the kernel config with the one in the meta-xilinx layer and there
> were not any significant differences.
> 
> 
> 
> Suspecting the device tree I tried booting the meta-xilinx generated
> kernel using the dtb from the Xilinx release images rather than the one
> built using yocto. The i2c initialised correctly in this instance and the
> pl330 dma driver does not report any errors.
> 
> 
> 
> I tried building the device tree blob using  the arch/arm/boot/dts/zynq-
> zc706.dts from the linux-xlnx github. When I boot the kernel using this
> dtb the i2c also initialises correctly.
> 
> 
> 
> This suggests that errors are caused by dts files in the meta-xilinx layer
> under conf/machine/boards which built by default by the meta-xilinx layer.
> Are there some changes which I need to apply to these files to get the
> zc706 kernel to initialise ok or should the meta-xilinx layer be using the
> device tree from the linux-xlnx kernel tree?
> 
> 
> 
> Thanks
> 
> 
> 
> Stephen