On Wed, May 25, 2011 at 7:16 AM, Gabbasov, Andrew <andrew_gabba...@mentor.com> wrote: > Hello Matthew, > > You have made a patch > "powerpc/fsl_booke: Add support to boot from core other than 0" some time > ago, so you probably worked with booting the kernel on a cpu subset, > particularly on the core other than 0. > > Could you please describe any details how you ran the kernel from u-boot on > a non-0 cpu?
I did this via kexec not via u-boot. In this method I would reboot on any one of the cores and it would bring up the other cores. > I have a problem trying to boot linux on p4080ds platform on any non-0 cpu > (as a first step to running AMP or mixed AMP/SMP configuration). I'm trying > to run 2.6.34.6 kernel with some Freescale patches in SMP configuration with > full original device tree and device tree with some cpu nodes removed. I'm > using the u-boot script, shown at the bottom of this message. > > If I run "bootm go" after the script commands (thus running the kernel on > cpu 0), the kernel runs fine. > > When I'm trying to run the SMP kernel with full device tree on cpu 1 using > the following commands after the script: > fdt boot 1 > cpu 1 release 0 1 c00000 - > the kernel begins to run, but soon crashes. Possible reasons > are: "Unrecoverable FP Unavailable Exception", at nearly random > place; memory allocation errors somewhere in DPAA code and then segmentation > fault (sig 11); unknown exception (sig 4). Sometimes it doesn't even show > anything on the console (too early exception?), but sometimes it boots > successfully up to the shell prompt. Is the single core boot stable at this point? > When I'm trying to run the SMP kernel with the device tree with cpu 0 > stripped out (commented out the whole cpu0 node and all properties referring > to it with &cpu0), using the following commands after the script: > fdt boot 1 > cpu 1 release 0 0 c00000 - > [Note the difference in the parameter to 'cpu 1 release' command, > it should be a logical cpu number, which is different] > the result is almost the same, the kernel crashes too. The reasons are > similar to the above, with more often "Unrecoverable FP Unavailable > Exception". Can you send me the kernel boot logs and kernel defconfig? (off list perhaps) > > Can you give any advise why can this happen, and what I could be doing > wrong? Did you build your kernel relocatable? Did you use the -b option when compiling your device tree? We do have a hypervisor for this part which might be a more suitable and tested solution depending on what you are trying to accomplish. I'm not sure that anyone has explicitly tested AMP on a p4080. -M _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
