"I wonder if we also have some dependency to some earlier versions of u-boot as u-boot now only muxes the essential pins?" This is exactly the problem in my case. I added "#define CONFIG_SYS_ENABLE_PADS_ALL" in u-boot/include/configs/omap4_common.h and now there is output. I guess the reason that the u-boot worked out-of-box for Ben but not for me is that I missed some configurations in v3.12 kernel. I image there is a config options that tells the kernel to take care of the non-essential pins that used to be the responsibility of u-boot. Could you confirm my hypothesis? And if so, could you kindly suggest what's the name of the config option? Thank you! On Wed, Nov 20, 2013 at 12:35 PM, Tony Lindgren <tony@xxxxxxxxxxx> wrote: > * Ben Gamari <bgamari.foss@xxxxxxxxx> [131119 19:07]: >> Chao Xu <caesarxuchao@xxxxxxxxx> writes: >> >> > Hi, >> > >> > I also try to boot v3.12 on my pandaboard rev A2, but it hangs at >> > "starting kernel". My SD card is originally loaded with a linaro 12.04 >> > ubuntu-developer image. I have tried with v3.7 and v3.8 uImage and >> > both of them work normally, but v3.12 hangs. Is there any trick I >> > missed? Do I need to use the new u-boot as used by Ben? >> > >> I've written up some of my experiences bringing up 3.12 on the >> PandaBoard here[1]. You may find it helpful. Regardless, I would >> definitely try upgrading u-boot. > > Nice investigative blogging :) > > Care to also update it with the other issues remaining on pandaboard? > Sounds like we're pretty close to having things working nicely with > mainline kernel on it, so let's just fix those issues ASAP. > > I'm aware of at least two issues: > > 1. The WLAN not working after a soft reset, or if the interface is > reset with ifconfig down. This could be a typo somewhere in the > .dts file for the WLAN regulator or something like that. > > 2. Suspend and resume does not wake-up from serial console and spews > a bunch of warnings. The wake-up issue can be fixed with the new > the new interrupts-extended property to use the wake IRQs, I'll > try to update my patches for that today. > >> > And here is a separate problem with building u-boot. I cloned the >> > upstream u-boot repository. The latest commit is >> > c2e5e802ecb7ab668ce9911b210ed68c804b349f. Then I did: >> > make ARCH=arm CROSS_COMPILE=arm-linux-gnueabi- omap4_panda_config >> > make ARCH=arm CROSS_COMPILE=arm-linux-gnueabi- -j8 >> > cp MLO u-boot.img /media/boot/ >> > But when turn on my pandaboard, there is NO output from the serial >> > console. I didn't change the other file in the boot partition. They >> > are from linaro 12.04 ubuntu-developer image. >> > >> I would check that you have earlyprintk enabled (both in the kernel >> configuration as well as on the kernel command line). Moreover, ensure >> that the correct serial devices is selected for low-level debug output >> (in the kernel configuration). > > I wonder if we also have some dependency to some earlier versions of > u-boot as u-boot now only muxes the essential pins? > > Regards, > > Tony > > >> [1] http://bgamari.github.io/posts/2013-11-17-running-modern-kernel-on-pandaboard.html > > -- Regards, Chao Xu -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
