[PATCH V4 0/2] powerpc/kexec: Reset endianess before kexec

[Samuel Mendoza-Jonas <sam.mj@au1.ibm.com>]

Older ppc64 kernels, namely those missing FIXUP_ENDIAN or opal_reinit_cpus,
will fail to boot if started via kexec from a little-endian kernel.
The following two patches make sure that the current endianess is reset to
big-endian just before entering the target kernel, and are accompanied by
a separate patch to kexec-lite that resets the endianess of the boot cpu.

Changes in v4:
As pointed out by Ben since interrupts are already disabled before checking
that all secondaries are in OPAL, we can make the call to opal_reinit_cpus
in C, in pnv_kexec_cpu_down().

Changes in v3: 
Move the call to opal_reinit_cpus into kexec_sequence so we can call it in
real mode with interrupts disabled. Update the kexec_sequence prototype so
that we can check if OPAL is present.
Fix the !CONFIG_PPC_BOOK3S_64 case in kexec_wait to correctly branch to 0x60

Changes in v2:
Add an #ifdef for subarch-specific code
Neaten the endian check (and extra call to mfmsr!) by modifying the msr and
branching to the target kernel in the same call to rfid.


Samuel Mendoza-Jonas (2):
  powerpc/kexec: Reset secondary cpu endianess before kexec
  powerpc/kexec: Reset HILE before kexec_sequence

 arch/powerpc/kernel/misc_64.S          | 13 +++++++++++--
 arch/powerpc/platforms/powernv/setup.c |  7 +++++++
 2 files changed, 18 insertions(+), 2 deletions(-)

-- 
2.4.6