[PATCH v3 04/15] powerpc/32: move MSR_PR test into EXCEPTION_PROLOG_0

From: Christophe Leroy
Date: Tue Sep 10 2019 - 05:17:51 EST


In order to simplify VMAP stack implementation, move
MSR_PR test into EXCEPTION_PROLOG_0.

This requires to not modify cr0 between EXCEPTION_PROLOG_0
and EXCEPTION_PROLOG_1.

Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxx>
---
arch/powerpc/kernel/head_32.h | 4 ++--
arch/powerpc/kernel/head_8xx.S | 39 ++++++++++++++++++++-------------------
2 files changed, 22 insertions(+), 21 deletions(-)

diff --git a/arch/powerpc/kernel/head_32.h b/arch/powerpc/kernel/head_32.h
index 8e345f8d4b0e..436ffd862d2a 100644
--- a/arch/powerpc/kernel/head_32.h
+++ b/arch/powerpc/kernel/head_32.h
@@ -19,12 +19,12 @@
.macro EXCEPTION_PROLOG_0
mtspr SPRN_SPRG_SCRATCH0,r10
mtspr SPRN_SPRG_SCRATCH1,r11
+ mfspr r11, SPRN_SRR1 /* check whether user or kernel */
mfcr r10
+ andi. r11, r11, MSR_PR
.endm

.macro EXCEPTION_PROLOG_1
- mfspr r11,SPRN_SRR1 /* check whether user or kernel */
- andi. r11,r11,MSR_PR
tophys(r11,r1) /* use tophys(r1) if kernel */
beq 1f
mfspr r11,SPRN_SPRG_THREAD
diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index fb284d95c76a..175c3cfc8014 100644
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -497,8 +497,8 @@ InstructionTLBError:
DataTLBError:
EXCEPTION_PROLOG_0
mfspr r11, SPRN_DAR
- cmpwi cr0, r11, RPN_PATTERN
- beq- FixupDAR /* must be a buggy dcbX, icbi insn. */
+ cmpwi cr1, r11, RPN_PATTERN
+ beq- cr1, FixupDAR /* must be a buggy dcbX, icbi insn. */
DARFixed:/* Return from dcbx instruction bug workaround */
EXCEPTION_PROLOG_1
EXCEPTION_PROLOG_2
@@ -531,9 +531,9 @@ DARFixed:/* Return from dcbx instruction bug workaround */
DataBreakpoint:
EXCEPTION_PROLOG_0
mfspr r11, SPRN_SRR0
- cmplwi cr0, r11, (.Ldtlbie - PAGE_OFFSET)@l
+ cmplwi cr1, r11, (.Ldtlbie - PAGE_OFFSET)@l
cmplwi cr7, r11, (.Litlbie - PAGE_OFFSET)@l
- beq- cr0, 11f
+ beq- cr1, 11f
beq- cr7, 11f
EXCEPTION_PROLOG_1
EXCEPTION_PROLOG_2
@@ -578,9 +578,9 @@ FixupDAR:/* Entry point for dcbx workaround. */
mfspr r10, SPRN_SRR0
mtspr SPRN_MD_EPN, r10
rlwinm r11, r10, 16, 0xfff8
- cmpli cr0, r11, PAGE_OFFSET@h
+ cmpli cr1, r11, PAGE_OFFSET@h
mfspr r11, SPRN_M_TWB /* Get level 1 table */
- blt+ 3f
+ blt+ cr1, 3f
rlwinm r11, r10, 16, 0xfff8

0: cmpli cr7, r11, (PAGE_OFFSET + 0x1800000)@h
@@ -595,7 +595,7 @@ FixupDAR:/* Entry point for dcbx workaround. */
3:
lwz r11, (swapper_pg_dir-PAGE_OFFSET)@l(r11) /* Get the level 1 entry */
mtspr SPRN_MD_TWC, r11
- mtcr r11
+ mtcrf 0x01, r11
mfspr r11, SPRN_MD_TWC
lwz r11, 0(r11) /* Get the pte */
bt 28,200f /* bit 28 = Large page (8M) */
@@ -608,16 +608,16 @@ FixupDAR:/* Entry point for dcbx workaround. */
* no need to include them here */
xoris r10, r11, 0x7c00 /* check if major OP code is 31 */
rlwinm r10, r10, 0, 21, 5
- cmpwi cr0, r10, 2028 /* Is dcbz? */
- beq+ 142f
- cmpwi cr0, r10, 940 /* Is dcbi? */
- beq+ 142f
- cmpwi cr0, r10, 108 /* Is dcbst? */
- beq+ 144f /* Fix up store bit! */
- cmpwi cr0, r10, 172 /* Is dcbf? */
- beq+ 142f
- cmpwi cr0, r10, 1964 /* Is icbi? */
- beq+ 142f
+ cmpwi cr1, r10, 2028 /* Is dcbz? */
+ beq+ cr1, 142f
+ cmpwi cr1, r10, 940 /* Is dcbi? */
+ beq+ cr1, 142f
+ cmpwi cr1, r10, 108 /* Is dcbst? */
+ beq+ cr1, 144f /* Fix up store bit! */
+ cmpwi cr1, r10, 172 /* Is dcbf? */
+ beq+ cr1, 142f
+ cmpwi cr1, r10, 1964 /* Is icbi? */
+ beq+ cr1, 142f
141: mfspr r10,SPRN_M_TW
b DARFixed /* Nope, go back to normal TLB processing */

@@ -676,8 +676,9 @@ FixupDAR:/* Entry point for dcbx workaround. */
add r10, r10, r30 ;b 151f
add r10, r10, r31
151:
- rlwinm. r11,r11,19,24,28 /* offset into jump table for reg RA */
- beq 152f /* if reg RA is zero, don't add it */
+ rlwinm r11,r11,19,24,28 /* offset into jump table for reg RA */
+ cmpwi cr1, r11, 0
+ beq cr1, 152f /* if reg RA is zero, don't add it */
addi r11, r11, 150b@l /* add start of table */
mtctr r11 /* load ctr with jump address */
rlwinm r11,r11,0,16,10 /* make sure we don't execute this more than once */
--
2.13.3