Use M_TW instead of M_TWB for storing Level 1 table address as M_TWB requires
4k aligned tables, which is only the case with 4k pages.
Consequently, we have to calculate the level 1 table index by ourselves.
Signed-off-by: Christophe Leroy <christophe.le...@c-s.fr>
---
arch/powerpc/kernel/head_8xx.S | 44 ++++++++++++++++++---------------
1 files changed, 24 insertions(+), 20 deletions(-)
diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index 6c2aa33..25c782d 100644
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -276,8 +276,8 @@ SystemCall:
. = 0x1100
/*
* For the MPC8xx, this is a software tablewalk to load the instruction
- * TLB. It is modelled after the example in the Motorola manual. The task
- * switch loads the M_TWB register with the pointer to the first level table.
+ * TLB. The task switch loads the M_TW register with the pointer to the first
+ * level table.
* If we discover there is no second level table (value is zero) or if there
* is an invalid pte, we load that into the TLB, which causes another fault
* into the TLB Error interrupt where we can handle such problems.
@@ -299,7 +299,6 @@ InstructionTLBMiss:
#endif
DO_8xx_CPU6(0x3780, r3)
mtspr SPRN_MD_EPN, r10 /* Have to use MD_EPN for walk, MI_EPN
can't */
- mfspr r10, SPRN_M_TWB /* Get level 1 table entry address */
/* If we are faulting a kernel address, we have to use the
* kernel page tables.
@@ -307,13 +306,16 @@ InstructionTLBMiss:
#ifdef CONFIG_MODULES
/* Only modules will cause ITLB Misses as we always
* pin the first 8MB of kernel memory */
- andi. r11, r10, 0x0800 /* Address >= 0x80000000 */
+ andis. r11, r10, 0x8000 /* Address >= 0x80000000 */
+#endif
+ mfspr r11, SPRN_M_TW /* Get level 1 table base address */
+#ifdef CONFIG_MODULES
beq 3f
- lis r11, swapper_pg_dir@h
- rlwimi r10, r11, 0, 2, 19
+ lis r11, (swapper_pg_dir-PAGE_OFFSET)@h
3:
#endif
- lwz r11, 0(r10) /* Get the level 1 entry */
+ rlwinm r10, r10, 12, 20, 29 /* Extract level 1 index */
+ lwzx r11, r10, r11 /* Get the level 1 entry */
rlwinm. r10, r11,0,0,19 /* Extract page descriptor page address */
beq 2f /* If zero, don't try to find a pte */
@@ -374,17 +376,18 @@ DataStoreTLBMiss:
#endif
EXCEPTION_PROLOG_0
mtspr SPRN_SPRG_SCRATCH2, r10
- mfspr r10, SPRN_M_TWB /* Get level 1 table entry address */
+ mfspr r10, SPRN_MD_EPN
/* If we are faulting a kernel address, we have to use the
* kernel page tables.
*/
- andi. r11, r10, 0x0800
+ andis. r11, r10, 0x8000
+ mfspr r11, SPRN_M_TW /* Get level 1 table base address */
beq 3f
- lis r11, swapper_pg_dir@h
- rlwimi r10, r11, 0, 2, 19
+ lis r11, (swapper_pg_dir-PAGE_OFFSET)@h
3:
- lwz r11, 0(r10) /* Get the level 1 entry */
+ rlwinm r10, r10, 12, 20, 29 /* Extract level 1 index */
+ lwzx r11, r10, r11 /* Get the level 1 entry */
rlwinm. r10, r11,0,0,19 /* Extract page descriptor page address */
beq 2f /* If zero, don't try to find a pte */
@@ -521,11 +524,11 @@ FixupDAR:/* Entry point for dcbx workaround. */
andis. r11, r10, 0x8000 /* Address >= 0x80000000 */
DO_8xx_CPU6(0x3780, r3)
mtspr SPRN_MD_EPN, r10
- mfspr r11, SPRN_M_TWB /* Get level 1 table entry address */
+ mfspr r11, SPRN_M_TW /* Get level 1 table base address */
beq- 3f /* Branch if user space */
lis r11, (swapper_pg_dir-PAGE_OFFSET)@h
- rlwimi r11, r10, 32-20, 0xffc /* r11 = r11&~0xffc|(r10>>20)&0xffc */
-3: lwz r11, 0(r11) /* Get the level 1 entry */
+3: rlwinm r10, r10, 12, 20, 29 /* Extract level 1 index */
+ lwzx r11, r10, r11 /* Get the level 1 entry */
DO_8xx_CPU6(0x3b80, r3)
mtspr SPRN_MD_TWC, r11 /* Load pte table base address */
mfspr r11, SPRN_MD_TWC /* ....and get the pte address */
@@ -534,6 +537,7 @@ FixupDAR:/* Entry point for dcbx workaround. */
lwz r3, 8(r0) /* restore r3 from memory */
#endif
/* concat physical page address(r11) and page offset(r10) */
+ mfspr r10, SPRN_SRR0
rlwimi r11, r10, 0, 20, 31
lwz r11,0(r11)
/* Check if it really is a dcbx instruction. */
@@ -688,11 +692,11 @@ start_here:
#ifdef CONFIG_8xx_CPU6
lis r4, cpu6_errata_word@h
ori r4, r4, cpu6_errata_word@l
- li r3, 0x3980
+ li r3, 0x3f80
stw r3, 12(r4)
lwz r3, 12(r4)
#endif
- mtspr SPRN_M_TWB, r6
+ mtspr SPRN_M_TW, r6
lis r4,2f@h
ori r4,r4,2f@l
tophys(r4,r4)
@@ -866,10 +870,10 @@ _GLOBAL(set_context)
lis r6, cpu6_errata_word@h
ori r6, r6, cpu6_errata_word@l
tophys (r4, r4)
- li r7, 0x3980
+ li r7, 0x3f80
stw r7, 12(r6)
lwz r7, 12(r6)
- mtspr SPRN_M_TWB, r4 /* Update MMU base address */
+ mtspr SPRN_M_TW, r4 /* Update MMU base address */
li r7, 0x3380
stw r7, 12(r6)
lwz r7, 12(r6)
@@ -877,7 +881,7 @@ _GLOBAL(set_context)
#else
mtspr SPRN_M_CASID,r3 /* Update context */
tophys (r4, r4)
- mtspr SPRN_M_TWB, r4 /* and pgd */
+ mtspr SPRN_M_TW, r4 /* and pgd */
#endif
SYNC
blr
--
1.7.1
_______________________________________________
Linuxppc-dev mailing list
Linuxppc-dev@lists.ozlabs.org
https://lists.ozlabs.org/listinfo/linuxppc-dev
