[9fans] raspberry pi kernel update

[9fans] raspberry pi kernel update

[Richard Miller]

I've made an update to the rpi 2 & 3 kernel source (armv7.s and rebootcode.s)
which fixes a couple of long-standing flaws in the multicore startup:

- dependency on the order of object files for the 5l command in the mkfile,
  resulting in "lock loop" or "only 1 cpu started" error for some configurations
- flakiness in /dev/reboot, making it unreliable except with *ncpu=1

It should now be possible consistently to reboot a pi in multicore mode from
a named file using the 'reboot' or 'fshalt -r' command.  This extends the
possibilities for using the Plan 9 kernel itself as a boot loader (with an rc
script as /boot/boot), eg to boot from an AoE server or over a wifi connection.

Re: [9fans] raspberry pi kernel update

[Richard Miller]

Sorry for posting twice, but the first attempt seems to have sat
on some server for a week:

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[9fans] raspberry pi kernel update

[Richard Miller]

I've made an update to the rpi 2 & 3 kernel source (armv7.s and rebootcode.s
in /n/sources/contrib/miller/9/bcm) to correct a couple of long-standing
flaws in the multicore startup:

- dependency on the order of object files for the 5l command in the mkfile,
  resulting in "lock loop" or "only 1 cpu started" error for some configurations
- flakiness in /dev/reboot, making it unreliable except with *ncpu=1

It should now be possible consistently to reboot a pi in multicore mode from
a named file using the 'reboot' or 'fshalt -r' command.  This extends the
possibilities for using the Plan 9 kernel itself as a boot loader (with an rc
script as /boot/boot), eg to load a kernel from an AoE server or over wifi.