[PATCH 04/10] powerpc/hash32: use physical address directly in hash handlers.

From: Christophe Leroy
Date: Fri Jan 25 2019 - 07:34:51 EST


Since commit c62ce9ef97ba ("powerpc: remove remaining bits from
CONFIG_APUS"), tophys() has become a pure constant operation.
PAGE_OFFSET is known at compile time so the physical address
can be builtin directly.

Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxx>
---
arch/powerpc/mm/hash_low_32.S | 62 +++++++++++++++++++------------------------
arch/powerpc/mm/ppc_mmu_32.c | 6 +++--
2 files changed, 31 insertions(+), 37 deletions(-)

diff --git a/arch/powerpc/mm/hash_low_32.S b/arch/powerpc/mm/hash_low_32.S
index 1e2df3e9f9ea..2afd0dce6d6a 100644
--- a/arch/powerpc/mm/hash_low_32.S
+++ b/arch/powerpc/mm/hash_low_32.S
@@ -47,14 +47,13 @@ mmu_hash_lock:
* Returns to the caller if the access is illegal or there is no
* mapping for the address. Otherwise it places an appropriate PTE
* in the hash table and returns from the exception.
- * Uses r0, r3 - r8, r10, ctr, lr.
+ * Uses r0, r3 - r6, r8, r10, ctr, lr.
*/
.text
_GLOBAL(hash_page)
- tophys(r7,0) /* gets -KERNELBASE into r7 */
#ifdef CONFIG_SMP
- addis r8,r7,mmu_hash_lock@h
- ori r8,r8,mmu_hash_lock@l
+ lis r8, (mmu_hash_lock - PAGE_OFFSET)@h
+ ori r8, r8, (mmu_hash_lock - PAGE_OFFSET)@l
lis r0,0x0fff
b 10f
11: lwz r6,0(r8)
@@ -77,7 +76,7 @@ _GLOBAL(hash_page)
lis r5,swapper_pg_dir@ha /* if kernel address, use */
addi r5,r5,swapper_pg_dir@l /* kernel page table */
rlwimi r3,r9,32-12,29,29 /* MSR_PR -> _PAGE_USER */
-112: add r5,r5,r7 /* convert to phys addr */
+112: tophys(r5, r5)
#ifndef CONFIG_PTE_64BIT
rlwimi r5,r4,12,20,29 /* insert top 10 bits of address */
lwz r8,0(r5) /* get pmd entry */
@@ -144,25 +143,24 @@ retry:

#ifdef CONFIG_SMP
eieio
- addis r8,r7,mmu_hash_lock@ha
+ lis r8, (mmu_hash_lock - PAGE_OFFSET)@ha
li r0,0
- stw r0,mmu_hash_lock@l(r8)
+ stw r0, (mmu_hash_lock - PAGE_OFFSET)@l(r8)
#endif

/* Return from the exception */
lwz r5,_CTR(r11)
mtctr r5
lwz r0,GPR0(r11)
- lwz r7,GPR7(r11)
lwz r8,GPR8(r11)
b fast_exception_return

#ifdef CONFIG_SMP
hash_page_out:
eieio
- addis r8,r7,mmu_hash_lock@ha
+ lis r8, (mmu_hash_lock - PAGE_OFFSET)@ha
li r0,0
- stw r0,mmu_hash_lock@l(r8)
+ stw r0, (mmu_hash_lock - PAGE_OFFSET)@l(r8)
blr
#endif /* CONFIG_SMP */

@@ -208,11 +206,9 @@ _GLOBAL(add_hash_page)
SYNC_601
isync

- tophys(r7,0)
-
#ifdef CONFIG_SMP
- addis r6,r7,mmu_hash_lock@ha
- addi r6,r6,mmu_hash_lock@l
+ lis r6, (mmu_hash_lock - PAGE_OFFSET)@ha
+ addi r6, r6, (mmu_hash_lock - PAGE_OFFSET)@l
10: lwarx r0,0,r6 /* take the mmu_hash_lock */
cmpi 0,r0,0
bne- 11f
@@ -257,8 +253,8 @@ _GLOBAL(add_hash_page)

9:
#ifdef CONFIG_SMP
- addis r6,r7,mmu_hash_lock@ha
- addi r6,r6,mmu_hash_lock@l
+ lis r6, (mmu_hash_lock - PAGE_OFFSET)@ha
+ addi r6, r6, (mmu_hash_lock - PAGE_OFFSET)@l
eieio
li r0,0
stw r0,0(r6) /* clear mmu_hash_lock */
@@ -278,10 +274,8 @@ _GLOBAL(add_hash_page)
* It is designed to be called with the MMU either on or off.
* r3 contains the VSID, r4 contains the virtual address,
* r5 contains the linux PTE, r6 contains the old value of the
- * linux PTE (before setting _PAGE_HASHPTE) and r7 contains the
- * offset to be added to addresses (0 if the MMU is on,
- * -KERNELBASE if it is off). r10 contains the upper half of
- * the PTE if CONFIG_PTE_64BIT.
+ * linux PTE (before setting _PAGE_HASHPTE). r10 contains the
+ * upper half of the PTE if CONFIG_PTE_64BIT.
* On SMP, the caller should have the mmu_hash_lock held.
* We assume that the caller has (or will) set the _PAGE_HASHPTE
* bit in the linux PTE in memory. The value passed in r6 should
@@ -342,7 +336,7 @@ END_FTR_SECTION_IFCLR(CPU_FTR_NEED_COHERENT)
patch_site 1f, patch__hash_page_A1
patch_site 2f, patch__hash_page_A2
/* Get the address of the primary PTE group in the hash table (r3) */
-0: addis r0,r7,Hash_base@h /* base address of hash table */
+0: lis r0, (Hash_base - PAGE_OFFSET)@h /* base address of hash table */
1: rlwimi r0,r3,LG_PTEG_SIZE,HASH_LEFT,HASH_RIGHT /* VSID -> hash */
2: rlwinm r3,r4,20+LG_PTEG_SIZE,HASH_LEFT,HASH_RIGHT /* PI -> hash */
xor r3,r3,r0 /* make primary hash */
@@ -356,10 +350,10 @@ END_FTR_SECTION_IFCLR(CPU_FTR_NEED_COHERENT)
beq+ 10f /* no PTE: go look for an empty slot */
tlbie r4

- addis r4,r7,htab_hash_searches@ha
- lwz r6,htab_hash_searches@l(r4)
+ lis r4, (htab_hash_searches - PAGE_OFFSET)@ha
+ lwz r6, (htab_hash_searches - PAGE_OFFSET)@l(r4)
addi r6,r6,1 /* count how many searches we do */
- stw r6,htab_hash_searches@l(r4)
+ stw r6, (htab_hash_searches - PAGE_OFFSET)@l(r4)

/* Search the primary PTEG for a PTE whose 1st (d)word matches r5 */
mtctr r0
@@ -391,10 +385,10 @@ END_FTR_SECTION_IFCLR(CPU_FTR_NEED_COHERENT)
beq+ found_empty

/* update counter of times that the primary PTEG is full */
- addis r4,r7,primary_pteg_full@ha
- lwz r6,primary_pteg_full@l(r4)
+ lis r4, (primary_pteg_full - PAGE_OFFSET)@ha
+ lwz r6, (primary_pteg_full - PAGE_OFFSET)@l(r4)
addi r6,r6,1
- stw r6,primary_pteg_full@l(r4)
+ stw r6, (primary_pteg_full - PAGE_OFFSET)@l(r4)

patch_site 0f, patch__hash_page_C
/* Search the secondary PTEG for an empty slot */
@@ -428,8 +422,8 @@ END_FTR_SECTION_IFCLR(CPU_FTR_NEED_COHERENT)
* lockup here but that shouldn't happen
*/

-1: addis r4,r7,next_slot@ha /* get next evict slot */
- lwz r6,next_slot@l(r4)
+1: lis r4, (next_slot - PAGE_OFFSET)@ha /* get next evict slot */
+ lwz r6, (next_slot - PAGE_OFFSET)@l(r4)
addi r6,r6,HPTE_SIZE /* search for candidate */
andi. r6,r6,7*HPTE_SIZE
stw r6,next_slot@l(r4)
@@ -501,8 +495,6 @@ htab_hash_searches:
* We assume that there is a hash table in use (Hash != 0).
*/
_GLOBAL(flush_hash_pages)
- tophys(r7,0)
-
/*
* We disable interrupts here, even on UP, because we want
* the _PAGE_HASHPTE bit to be a reliable indication of
@@ -547,10 +539,10 @@ _GLOBAL(flush_hash_pages)
SET_V(r11) /* set V (valid) bit */

#ifdef CONFIG_SMP
- addis r9,r7,mmu_hash_lock@ha
- addi r9,r9,mmu_hash_lock@l
+ lis r9, (mmu_hash_lock - PAGE_OFFSET)@ha
+ addi r9, r9, (mmu_hash_lock - PAGE_OFFSET)@l
CURRENT_THREAD_INFO(r8, r1)
- add r8,r8,r7
+ tophys(r8, r8)
lwz r8,TI_CPU(r8)
oris r8,r8,9
10: lwarx r0,0,r9
@@ -584,7 +576,7 @@ _GLOBAL(flush_hash_pages)
patch_site 1f, patch__flush_hash_A1
patch_site 2f, patch__flush_hash_A2
/* Get the address of the primary PTE group in the hash table (r3) */
-0: addis r8,r7,Hash_base@h /* base address of hash table */
+0: lis r8, (Hash_base - PAGE_OFFSET)@h /* base address of hash table */
1: rlwimi r8,r3,LG_PTEG_SIZE,HASH_LEFT,HASH_RIGHT /* VSID -> hash */
2: rlwinm r0,r4,20+LG_PTEG_SIZE,HASH_LEFT,HASH_RIGHT /* PI -> hash */
xor r8,r0,r8 /* make primary hash */
diff --git a/arch/powerpc/mm/ppc_mmu_32.c b/arch/powerpc/mm/ppc_mmu_32.c
index 3f4193201ee7..fb747bb0b3e4 100644
--- a/arch/powerpc/mm/ppc_mmu_32.c
+++ b/arch/powerpc/mm/ppc_mmu_32.c
@@ -231,7 +231,8 @@ void __init MMU_init_hw(void)
if (lg_n_hpteg > 16)
mb2 = 16 - LG_HPTEG_SIZE;

- modify_instruction_site(&patch__hash_page_A0, 0xffff, (unsigned int)Hash >> 16);
+ modify_instruction_site(&patch__hash_page_A0, 0xffff,
+ ((unsigned int)Hash - PAGE_OFFSET) >> 16);
modify_instruction_site(&patch__hash_page_A1, 0x7c0, mb << 6);
modify_instruction_site(&patch__hash_page_A2, 0x7c0, mb2 << 6);
modify_instruction_site(&patch__hash_page_B, 0xffff, hmask);
@@ -240,7 +241,8 @@ void __init MMU_init_hw(void)
/*
* Patch up the instructions in hashtable.S:flush_hash_page
*/
- modify_instruction_site(&patch__flush_hash_A0, 0xffff, (unsigned int)Hash >> 16);
+ modify_instruction_site(&patch__flush_hash_A0, 0xffff,
+ ((unsigned int)Hash - PAGE_OFFSET) >> 16);
modify_instruction_site(&patch__flush_hash_A1, 0x7c0, mb << 6);
modify_instruction_site(&patch__flush_hash_A2, 0x7c0, mb2 << 6);
modify_instruction_site(&patch__flush_hash_B, 0xffff, hmask);
--
2.13.3