On the 603, SDR1 is not used.
In order to free SPRN_SPRG2, use SPRN_SDR1 to store the pgdir
phys addr.
But only some bits of SDR1 can be used (0xffff01ff).
As the pgdir is 4k aligned, rotate it by 4 bits to the left.
Signed-off-by: Christophe Leroy <christophe.le...@csgroup.eu>
---
arch/powerpc/include/asm/reg.h | 1 -
arch/powerpc/kernel/head_book3s_32.S | 31 +++++++++++++++++++++-------
2 files changed, 24 insertions(+), 8 deletions(-)
diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h
index f877a576b338..a37ce826f6f6 100644
--- a/arch/powerpc/include/asm/reg.h
+++ b/arch/powerpc/include/asm/reg.h
@@ -1203,7 +1203,6 @@
#ifdef CONFIG_PPC_BOOK3S_32
#define SPRN_SPRG_SCRATCH0 SPRN_SPRG0
#define SPRN_SPRG_SCRATCH1 SPRN_SPRG1
-#define SPRN_SPRG_PGDIR SPRN_SPRG2
#define SPRN_SPRG_603_LRU SPRN_SPRG4
#endif
diff --git a/arch/powerpc/kernel/head_book3s_32.S
b/arch/powerpc/kernel/head_book3s_32.S
index 236a95d163be..51eef7b82f9c 100644
--- a/arch/powerpc/kernel/head_book3s_32.S
+++ b/arch/powerpc/kernel/head_book3s_32.S
@@ -457,8 +457,9 @@ InstructionTLBMiss:
lis r1, TASK_SIZE@h /* check if kernel address */
cmplw 0,r1,r3
#endif
- mfspr r2, SPRN_SPRG_PGDIR
+ mfspr r2, SPRN_SDR1
li r1,_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_EXEC
+ rlwinm r2, r2, 28, 0xfffff000
#ifdef CONFIG_MODULES
bgt- 112f
lis r2, (swapper_pg_dir - PAGE_OFFSET)@ha /* if kernel address,
use */
@@ -519,8 +520,9 @@ DataLoadTLBMiss:
mfspr r3,SPRN_DMISS
lis r1, TASK_SIZE@h /* check if kernel address */
cmplw 0,r1,r3
- mfspr r2, SPRN_SPRG_PGDIR
+ mfspr r2, SPRN_SDR1
li r1, _PAGE_PRESENT | _PAGE_ACCESSED
+ rlwinm r2, r2, 28, 0xfffff000
bgt- 112f
lis r2, (swapper_pg_dir - PAGE_OFFSET)@ha /* if kernel address,
use */
addi r2, r2, (swapper_pg_dir - PAGE_OFFSET)@l /* kernel page
table */
@@ -595,8 +597,9 @@ DataStoreTLBMiss:
mfspr r3,SPRN_DMISS
lis r1, TASK_SIZE@h /* check if kernel address */
cmplw 0,r1,r3
- mfspr r2, SPRN_SPRG_PGDIR
+ mfspr r2, SPRN_SDR1
li r1, _PAGE_RW | _PAGE_DIRTY | _PAGE_PRESENT | _PAGE_ACCESSED
+ rlwinm r2, r2, 28, 0xfffff000
bgt- 112f
lis r2, (swapper_pg_dir - PAGE_OFFSET)@ha /* if kernel address,
use */
addi r2, r2, (swapper_pg_dir - PAGE_OFFSET)@l /* kernel page
table */
@@ -889,9 +892,12 @@ __secondary_start:
tophys(r4,r2)
addi r4,r4,THREAD /* phys address of our thread_struct */
mtspr SPRN_SPRG_THREAD,r4
+BEGIN_MMU_FTR_SECTION
lis r4, (swapper_pg_dir - PAGE_OFFSET)@h
ori r4, r4, (swapper_pg_dir - PAGE_OFFSET)@l
- mtspr SPRN_SPRG_PGDIR, r4
+ rlwinm r4, r4, 4, 0xffff01ff
+ mtspr SPRN_SDR1, r4
+END_MMU_FTR_SECTION_IFCLR(MMU_FTR_HPTE_TABLE)
/* enable MMU and jump to start_secondary */
li r4,MSR_KERNEL
@@ -931,11 +937,13 @@ load_up_mmu:
tlbia /* Clear all TLB entries */
sync /* wait for tlbia/tlbie to finish */
TLBSYNC /* ... on all CPUs */
+BEGIN_MMU_FTR_SECTION
/* Load the SDR1 register (hash table base & size) */
lis r6,_SDR1@ha
tophys(r6,r6)
lwz r6,_SDR1@l(r6)
mtspr SPRN_SDR1,r6
+END_MMU_FTR_SECTION_IFSET(MMU_FTR_HPTE_TABLE)
/* Load the BAT registers with the values set up by MMU_init. */
lis r3,BATS@ha
@@ -991,9 +999,12 @@ start_here:
tophys(r4,r2)
addi r4,r4,THREAD /* init task's THREAD */
mtspr SPRN_SPRG_THREAD,r4
+BEGIN_MMU_FTR_SECTION
lis r4, (swapper_pg_dir - PAGE_OFFSET)@h
ori r4, r4, (swapper_pg_dir - PAGE_OFFSET)@l
- mtspr SPRN_SPRG_PGDIR, r4
+ rlwinm r4, r4, 4, 0xffff01ff
+ mtspr SPRN_SDR1, r4
+END_MMU_FTR_SECTION_IFCLR(MMU_FTR_HPTE_TABLE)
/* stack */
lis r1,init_thread_union@ha
@@ -1073,16 +1084,22 @@ _ENTRY(switch_mmu_context)
li r0,NUM_USER_SEGMENTS
mtctr r0
- lwz r4, MM_PGD(r4)
#ifdef CONFIG_BDI_SWITCH
/* Context switch the PTE pointer for the Abatron BDI2000.
* The PGDIR is passed as second argument.
*/
+ lwz r4, MM_PGD(r4)
lis r5, abatron_pteptrs@ha
stw r4, abatron_pteptrs@l + 0x4(r5)
+#endif
+BEGIN_MMU_FTR_SECTION
+#ifndef CONFIG_BDI_SWITCH
+ lwz r4, MM_PGD(r4)
#endif
tophys(r4, r4)
- mtspr SPRN_SPRG_PGDIR, r4
+ rlwinm r4, r4, 4, 0xffff01ff
+ mtspr SPRN_SDR1, r4
+END_MMU_FTR_SECTION_IFCLR(MMU_FTR_HPTE_TABLE)
li r4,0
isync
3:
--
2.25.0
