The 8xx has two special registers called EID (External Interrupt
Disable) and EIE (External Interrupt Enable) for clearing/setting
EE in MSR. It avoids the three instructions set mfmsr/ori/mtmsr or
mfmsr/rlwinm/mtmsr and it avoids using a general register.
We just have to write something in the special register to change MSR EE
bit. So we write r0 into the register, regardless of r0 value.
Writing to one of those two special registers also set the MSR RI bit,
but this bit is only unset during beginning of exception prolog and end
of exception epilog. When executing C-functions MSR RI is always set.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
GCC < 4.9 is unable to build this, saying:
arch/powerpc/mm/8xx_mmu.c:139:2: error: memory input 1 is not directly addressable
Change the one-element array into a simple variable to avoid this.
Fixes: 1458dd951f ("powerpc/8xx: Handle CPU6 ERRATA directly in mtspr() macro")
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Scott Wood <oss@buserror.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
MPC8xx has an ERRATA on the use of mtspr() for some registers
This patch includes the ERRATA handling directly into mtspr() macro
so that mtspr() users don't need to bother about that errata
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
Add missing SPRN defines into reg_8xx.h
Some of them are defined in mmu-8xx.h, so we include mmu-8xx.h in
reg_8xx.h, for that we remove references to PAGE_SHIFT in mmu-8xx.h
to have it self sufficient, as includers of reg_8xx.h don't all
include asm/page.h
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
from include/asm-powerpc. This is the result of a
mkdir arch/powerpc/include/asm
git mv include/asm-powerpc/* arch/powerpc/include/asm
Followed by a few documentation/comment fixups and a couple of places
where <asm-powepc/...> was being used explicitly. Of the latter only
one was outside the arch code and it is a driver only built for powerpc.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
