Microblaze needs to do lock_init very soon because MMU init calls lock functions.
Here is the explanation from Peter Zijlstra why we have to enable
__ARCH_WANTS_INTERRUPTS_ON_CTSW.
"So we schedule while holding rq->lock (for obvious reasons), but since
lockdep tracks held locks per tasks, we need to transfer the held state
from the prev to the next task. We do this by explicity calling
spin_release(&rq->lock) in context_switch() right before switch_to(),
and calling spin_acquire(&rq->lock) in
finish_task_switch()->finish_lock_switch().
Now, for some reason lockdep thinks that interrupts got enabled over the
context switch (git grep __ARCH_WANTS_INTERRUPTS_ON_CTSW arch/microblaze
doesn't seem to turn up anything).
Clearly trying to acquire the rq->lock with interrupts enabled is a bad
idea and lockdep warns you about this."
Signed-off-by: Michal Simek <monstr@monstr.eu>
If r7 is zero at kernel boot, or does not point to a valid DTB, then
we fall back to a DTB (assumed to be) linked statically in the kernel, instead
of blindly copying bogus cruft into the kernel DTB memory region
Signed-off-by: John Williams <john.williams@petalogix.com>
Signed-off-by: Michal Simek <monstr@monstr.eu>
This patch is based on patch from Steve Magnani.
There were bug for compiled-in rootfs. We have to move
moving rootfs which is in BSS section to _ebss section
which is at the end of kernel and then clear bss section
not vice-versa.
Signed-off-by: Michal Simek <monstr@monstr.eu>
This patch fixed parsing early parameters because
current implementation does that early parse DTS
command line and then parse CMDLINE line which is compiled-in.
For case that DTS doesn't contain command line is
copied command line from kernel with is done in prom.c
that's why I can remove it from machine_early_init.
Signed-off-by: Michal Simek <monstr@monstr.eu>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
Reviewed-by: Stephen Neuendorffer <stephen.neuendorffer@xilinx.com>
Acked-by: John Linn <john.linn@xilinx.com>
Acked-by: John Williams <john.williams@petalogix.com>
Signed-off-by: Michal Simek <monstr@monstr.eu>