[PATCH 4/9] powerpc/book3s/32: Use MMU_FTR_HPTE_TABLE in head_32.S

From: Christophe Leroy
Date: Fri Nov 09 2018 - 12:33:26 EST


Instead of manually patching a blr at hash_page() entry in
MMU_init_hw(), this patch adds a features section in head_32.S

Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxx>
---
arch/powerpc/kernel/head_32.S | 4 ++++
arch/powerpc/mm/ppc_mmu_32.c | 12 +-----------
2 files changed, 5 insertions(+), 11 deletions(-)

diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S
index 61ca27929355..068c1656c758 100644
--- a/arch/powerpc/kernel/head_32.S
+++ b/arch/powerpc/kernel/head_32.S
@@ -393,7 +393,9 @@ DataAccess:
bne 1f /* if not, try to put a PTE */
mfspr r4,SPRN_DAR /* into the hash table */
rlwinm r3,r10,32-15,21,21 /* DSISR_STORE -> _PAGE_RW */
+BEGIN_MMU_FTR_SECTION
bl hash_page
+END_MMU_FTR_SECTION_IFSET(MMU_FTR_HPTE_TABLE)
1: lwz r5,_DSISR(r11) /* get DSISR value */
mfspr r4,SPRN_DAR
EXC_XFER_LITE(0x300, handle_page_fault)
@@ -408,7 +410,9 @@ InstructionAccess:
beq 1f /* if so, try to put a PTE */
li r3,0 /* into the hash table */
mr r4,r12 /* SRR0 is fault address */
+BEGIN_MMU_FTR_SECTION
bl hash_page
+END_MMU_FTR_SECTION_IFSET(MMU_FTR_HPTE_TABLE)
1: mr r4,r12
andis. r5,r9,DSISR_SRR1_MATCH_32S@h /* Filter relevant SRR1 bits */
EXC_XFER_LITE(0x400, handle_page_fault)
diff --git a/arch/powerpc/mm/ppc_mmu_32.c b/arch/powerpc/mm/ppc_mmu_32.c
index f6f575bae3bc..3c7c73defcb6 100644
--- a/arch/powerpc/mm/ppc_mmu_32.c
+++ b/arch/powerpc/mm/ppc_mmu_32.c
@@ -184,20 +184,10 @@ void __init MMU_init_hw(void)

extern unsigned int hash_page_patch_A[];
extern unsigned int hash_page_patch_B[], hash_page_patch_C[];
- extern unsigned int hash_page[];
extern unsigned int flush_hash_patch_A[], flush_hash_patch_B[];

- if (!mmu_has_feature(MMU_FTR_HPTE_TABLE)) {
- /*
- * Put a blr (procedure return) instruction at the
- * start of hash_page, since we can still get DSI
- * exceptions on a 603.
- */
- hash_page[0] = 0x4e800020;
- flush_icache_range((unsigned long) &hash_page[0],
- (unsigned long) &hash_page[1]);
+ if (!mmu_has_feature(MMU_FTR_HPTE_TABLE))
return;
- }

if ( ppc_md.progress ) ppc_md.progress("hash:enter", 0x105);

--
2.13.3