The purpose of this serie is to optimise the handling of
TLB misses on the 603/e300.
Today the TLB miss handlers are implemented by more or less
copying the actions performed by the hash page handlers used
on processors having HASH pagetable.
This serie brings some simplification.
Christophe Leroy (10):
powerpc: simplify BDI switch
powerpc/603: Store PGDIR physical address in a SPRG
powerpc/603: use physical address directly in TLB miss handlers.
powerpc/hash32: use physical address directly in hash handlers.
powerpc/603: Don't handle kernel page TLB misses when not need
powerpc/603: Don't handle _PAGE_RW and _PAGE_DIRTY on ITLB misses
powerpc/603: let's handle PAGE_DIRTY directly
powerpc/603: Don't worry about _PAGE_USER in TLB miss handlers
powerpc/603: don't handle PAGE_ACCESSED in TLB miss handlers.
powerpc/book3s32: Reorder _PAGE_XXX flags to simplify TLB handling
arch/powerpc/include/asm/book3s/32/hash.h | 8 +--
arch/powerpc/include/asm/mmu.h | 2 +
arch/powerpc/include/asm/reg.h | 1 +
arch/powerpc/kernel/cpu_setup_6xx.S | 4 ++
arch/powerpc/kernel/head_32.S | 97 ++++++++++++++-----------------
arch/powerpc/kernel/head_40x.S | 5 +-
arch/powerpc/kernel/head_8xx.S | 1 +
arch/powerpc/mm/8xx_mmu.c | 7 +--
arch/powerpc/mm/hash_low_32.S | 68 +++++++++-------------
arch/powerpc/mm/ppc_mmu_32.c | 6 +-
10 files changed, 93 insertions(+), 106 deletions(-)
--
2.13.3
There is no reason to re-read each time the pointer at
location 0xf0 as it is fixed and known.
Signed-off-by: Christophe Leroy <[email protected]>
---
arch/powerpc/include/asm/mmu.h | 2 ++
arch/powerpc/kernel/head_32.S | 5 ++---
arch/powerpc/kernel/head_40x.S | 5 ++---
arch/powerpc/kernel/head_8xx.S | 1 +
arch/powerpc/mm/8xx_mmu.c | 7 ++-----
5 files changed, 9 insertions(+), 11 deletions(-)
diff --git a/arch/powerpc/include/asm/mmu.h b/arch/powerpc/include/asm/mmu.h
index 25607604a7a5..6d22a8e78fe2 100644
--- a/arch/powerpc/include/asm/mmu.h
+++ b/arch/powerpc/include/asm/mmu.h
@@ -356,6 +356,8 @@ extern void early_init_mmu_secondary(void);
extern void setup_initial_memory_limit(phys_addr_t first_memblock_base,
phys_addr_t first_memblock_size);
static inline void mmu_early_init_devtree(void) { }
+
+extern void *abatron_pteptrs[2];
#endif /* __ASSEMBLY__ */
#endif
diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S
index 05b08db3901d..c2f564690778 100644
--- a/arch/powerpc/kernel/head_32.S
+++ b/arch/powerpc/kernel/head_32.S
@@ -1027,9 +1027,8 @@ _ENTRY(switch_mmu_context)
* The PGDIR is passed as second argument.
*/
lwz r4,MM_PGD(r4)
- lis r5, KERNELBASE@h
- lwz r5, 0xf0(r5)
- stw r4, 0x4(r5)
+ lis r5, abatron_pteptrs@ha
+ stw r4, abatron_pteptrs@l + 0x4(r5)
#endif
li r4,0
isync
diff --git a/arch/powerpc/kernel/head_40x.S b/arch/powerpc/kernel/head_40x.S
index b19d78410511..11dd09d0ce1a 100644
--- a/arch/powerpc/kernel/head_40x.S
+++ b/arch/powerpc/kernel/head_40x.S
@@ -953,9 +953,8 @@ _GLOBAL(set_context)
/* Context switch the PTE pointer for the Abatron BDI2000.
* The PGDIR is the second parameter.
*/
- lis r5, KERNELBASE@h
- lwz r5, 0xf0(r5)
- stw r4, 0x4(r5)
+ lis r5, abatron_pteptrs@ha
+ stw r4, abatron_pteptrs@l + 0x4(r5)
#endif
sync
mtspr SPRN_PID,r3
diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index c3f776fda984..4a2e3ffdb5bb 100644
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -1012,5 +1012,6 @@ swapper_pg_dir:
/* Room for two PTE table poiners, usually the kernel and current user
* pointer to their respective root page table (pgdir).
*/
+ .globl abatron_pteptrs
abatron_pteptrs:
.space 8
diff --git a/arch/powerpc/mm/8xx_mmu.c b/arch/powerpc/mm/8xx_mmu.c
index b5f6d794281d..e2c32bdb6023 100644
--- a/arch/powerpc/mm/8xx_mmu.c
+++ b/arch/powerpc/mm/8xx_mmu.c
@@ -159,14 +159,11 @@ void set_context(unsigned long id, pgd_t *pgd)
{
s16 offset = (s16)(__pa(swapper_pg_dir));
-#ifdef CONFIG_BDI_SWITCH
- pgd_t **ptr = *(pgd_t ***)(KERNELBASE + 0xf0);
-
/* Context switch the PTE pointer for the Abatron BDI2000.
* The PGDIR is passed as second argument.
*/
- *(ptr + 1) = pgd;
-#endif
+ if (IS_ENABLED(CONFIG_BDI_SWITCH))
+ abatron_pteptrs[1] = pgd;
/* Register M_TWB will contain base address of level 1 table minus the
* lower part of the kernel PGDIR base address, so that all accesses to
--
2.13.3
Use SPRN_SPRG5 to store the current thread PGDIR and
avoid reading thread_struct->pgdir at every TLB miss.
Signed-off-by: Christophe Leroy <[email protected]>
---
arch/powerpc/include/asm/reg.h | 1 +
arch/powerpc/kernel/cpu_setup_6xx.S | 4 ++++
arch/powerpc/kernel/head_32.S | 28 ++++++++++++++++------------
3 files changed, 21 insertions(+), 12 deletions(-)
diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h
index 1c98ef1f2d5b..ba0ab1a1431b 100644
--- a/arch/powerpc/include/asm/reg.h
+++ b/arch/powerpc/include/asm/reg.h
@@ -1169,6 +1169,7 @@
#define SPRN_SPRG_SCRATCH1 SPRN_SPRG1
#define SPRN_SPRG_RTAS SPRN_SPRG2
#define SPRN_SPRG_603_LRU SPRN_SPRG4
+#define SPRN_SPRG_603_PGDIR SPRN_SPRG5
#endif
#ifdef CONFIG_40x
diff --git a/arch/powerpc/kernel/cpu_setup_6xx.S b/arch/powerpc/kernel/cpu_setup_6xx.S
index 8c069e96c478..4c91d1f640fe 100644
--- a/arch/powerpc/kernel/cpu_setup_6xx.S
+++ b/arch/powerpc/kernel/cpu_setup_6xx.S
@@ -24,6 +24,10 @@ BEGIN_MMU_FTR_SECTION
li r10,0
mtspr SPRN_SPRG_603_LRU,r10 /* init SW LRU tracking */
END_MMU_FTR_SECTION_IFSET(MMU_FTR_NEED_DTLB_SW_LRU)
+ lis r10, (swapper_pg_dir - PAGE_OFFSET)@h
+ ori r10, r10, (swapper_pg_dir - PAGE_OFFSET)@l
+ mtspr SPRN_SPRG_603_PGDIR, r10
+
BEGIN_FTR_SECTION
bl __init_fpu_registers
END_FTR_SECTION_IFCLR(CPU_FTR_FPU_UNAVAILABLE)
diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S
index c2f564690778..dbd15e03952a 100644
--- a/arch/powerpc/kernel/head_32.S
+++ b/arch/powerpc/kernel/head_32.S
@@ -502,16 +502,15 @@ InstructionTLBMiss:
mfspr r3,SPRN_IMISS
lis r1,PAGE_OFFSET@h /* check if kernel address */
cmplw 0,r1,r3
- mfspr r2,SPRN_SPRG_THREAD
+ mfspr r2, SPRN_SPRG_603_PGDIR
li r1,_PAGE_USER|_PAGE_PRESENT|_PAGE_EXEC /* low addresses tested as user */
- lwz r2,PGDIR(r2)
bge- 112f
mfspr r2,SPRN_SRR1 /* and MSR_PR bit from SRR1 */
rlwimi r1,r2,32-12,29,29 /* shift MSR_PR to _PAGE_USER posn */
lis r2,swapper_pg_dir@ha /* if kernel address, use */
addi r2,r2,swapper_pg_dir@l /* kernel page table */
-112: tophys(r2,r2)
- rlwimi r2,r3,12,20,29 /* insert top 10 bits of address */
+ tophys(r2,r2)
+112: rlwimi r2,r3,12,20,29 /* insert top 10 bits of address */
lwz r2,0(r2) /* get pmd entry */
rlwinm. r2,r2,0,0,19 /* extract address of pte page */
beq- InstructionAddressInvalid /* return if no mapping */
@@ -576,16 +575,15 @@ DataLoadTLBMiss:
mfspr r3,SPRN_DMISS
lis r1,PAGE_OFFSET@h /* check if kernel address */
cmplw 0,r1,r3
- mfspr r2,SPRN_SPRG_THREAD
+ mfspr r2, SPRN_SPRG_603_PGDIR
li r1,_PAGE_USER|_PAGE_PRESENT /* low addresses tested as user */
- lwz r2,PGDIR(r2)
bge- 112f
mfspr r2,SPRN_SRR1 /* and MSR_PR bit from SRR1 */
rlwimi r1,r2,32-12,29,29 /* shift MSR_PR to _PAGE_USER posn */
lis r2,swapper_pg_dir@ha /* if kernel address, use */
addi r2,r2,swapper_pg_dir@l /* kernel page table */
-112: tophys(r2,r2)
- rlwimi r2,r3,12,20,29 /* insert top 10 bits of address */
+ tophys(r2,r2)
+112: rlwimi r2,r3,12,20,29 /* insert top 10 bits of address */
lwz r2,0(r2) /* get pmd entry */
rlwinm. r2,r2,0,0,19 /* extract address of pte page */
beq- DataAddressInvalid /* return if no mapping */
@@ -660,16 +658,15 @@ DataStoreTLBMiss:
mfspr r3,SPRN_DMISS
lis r1,PAGE_OFFSET@h /* check if kernel address */
cmplw 0,r1,r3
- mfspr r2,SPRN_SPRG_THREAD
+ mfspr r2, SPRN_SPRG_603_PGDIR
li r1,_PAGE_RW|_PAGE_USER|_PAGE_PRESENT /* access flags */
- lwz r2,PGDIR(r2)
bge- 112f
mfspr r2,SPRN_SRR1 /* and MSR_PR bit from SRR1 */
rlwimi r1,r2,32-12,29,29 /* shift MSR_PR to _PAGE_USER posn */
lis r2,swapper_pg_dir@ha /* if kernel address, use */
addi r2,r2,swapper_pg_dir@l /* kernel page table */
-112: tophys(r2,r2)
- rlwimi r2,r3,12,20,29 /* insert top 10 bits of address */
+ tophys(r2,r2)
+112: rlwimi r2,r3,12,20,29 /* insert top 10 bits of address */
lwz r2,0(r2) /* get pmd entry */
rlwinm. r2,r2,0,0,19 /* extract address of pte page */
beq- DataAddressInvalid /* return if no mapping */
@@ -1030,6 +1027,13 @@ _ENTRY(switch_mmu_context)
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_603_PGDIR, r4
+END_MMU_FTR_SECTION_IFCLR(MMU_FTR_HPTE_TABLE)
li r4,0
isync
3:
--
2.13.3
PAGE_DIRTY corresponds to the C bit. If writing on
a page for which the C bit is not set, a DataStoreTLBMiss
is generated. No need to check it in DataLoadTLBMiss.
Signed-off-by: Christophe Leroy <[email protected]>
---
arch/powerpc/kernel/head_32.S | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)
diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S
index 2aec3f91c9f5..abbaf51b6f58 100644
--- a/arch/powerpc/kernel/head_32.S
+++ b/arch/powerpc/kernel/head_32.S
@@ -597,12 +597,10 @@ DataLoadTLBMiss:
stw r0,0(r2) /* update PTE (accessed bit) */
/* Convert linux-style PTE to low word of PPC-style PTE */
rlwinm r1,r0,32-10,31,31 /* _PAGE_RW -> PP lsb */
- rlwinm r2,r0,32-7,31,31 /* _PAGE_DIRTY -> PP lsb */
- and r1,r1,r2 /* writable if _RW and _DIRTY */
rlwimi r0,r0,32-1,30,30 /* _PAGE_USER -> PP msb */
rlwimi r0,r0,32-1,31,31 /* _PAGE_USER -> PP lsb */
ori r1,r1,0xe04 /* clear out reserved bits */
- andc r1,r0,r1 /* PP = user? (rw&dirty? 2: 3): 0 */
+ andc r1,r0,r1 /* PP = user? rw? 2: 3: 0 */
BEGIN_FTR_SECTION
rlwinm r1,r1,0,~_PAGE_COHERENT /* clear M (coherence not required) */
END_FTR_SECTION_IFCLR(CPU_FTR_NEED_COHERENT)
@@ -671,7 +669,7 @@ DataStoreTLBMiss:
lwz r0,0(r2) /* get linux-style pte */
andc. r1,r1,r0 /* check access & ~permission */
bne- DataAddressInvalid /* return if access not permitted */
- ori r0,r0,_PAGE_ACCESSED|_PAGE_DIRTY
+ ori r0,r0,_PAGE_ACCESSED
/*
* NOTE! We are assuming this is not an SMP system, otherwise
* we would need to update the pte atomically with lwarx/stwcx.
--
2.13.3
PP bits take user access into account, so no need to check _PAGE_USER
here. A DSI or ISI will be generated if needed.
Signed-off-by: Christophe Leroy <[email protected]>
---
arch/powerpc/kernel/head_32.S | 12 +++---------
1 file changed, 3 insertions(+), 9 deletions(-)
diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S
index abbaf51b6f58..44cc84857520 100644
--- a/arch/powerpc/kernel/head_32.S
+++ b/arch/powerpc/kernel/head_32.S
@@ -505,11 +505,9 @@ InstructionTLBMiss:
cmplw 0,r1,r3
#endif
mfspr r2, SPRN_SPRG_603_PGDIR
- li r1,_PAGE_USER|_PAGE_PRESENT|_PAGE_EXEC /* low addresses tested as user */
+ li r1,_PAGE_PRESENT | _PAGE_EXEC
#if defined(CONFIG_MODULES) || defined(CONFIG_DEBUG_PAGEALLOC)
bge- 112f
- mfspr r2,SPRN_SRR1 /* and MSR_PR bit from SRR1 */
- rlwimi r1,r2,32-12,29,29 /* shift MSR_PR to _PAGE_USER posn */
lis r2, (swapper_pg_dir - PAGE_OFFSET)@ha /* if kernel address, use */
addi r2, r2, (swapper_pg_dir - PAGE_OFFSET)@l /* kernel page table */
#endif
@@ -575,10 +573,8 @@ DataLoadTLBMiss:
lis r1,PAGE_OFFSET@h /* check if kernel address */
cmplw 0,r1,r3
mfspr r2, SPRN_SPRG_603_PGDIR
- li r1,_PAGE_USER|_PAGE_PRESENT /* low addresses tested as user */
+ li r1, _PAGE_PRESENT
bge- 112f
- mfspr r2,SPRN_SRR1 /* and MSR_PR bit from SRR1 */
- rlwimi r1,r2,32-12,29,29 /* shift MSR_PR to _PAGE_USER posn */
lis r2, (swapper_pg_dir - PAGE_OFFSET)@ha /* if kernel address, use */
addi r2, r2, (swapper_pg_dir - PAGE_OFFSET)@l /* kernel page table */
112: rlwimi r2,r3,12,20,29 /* insert top 10 bits of address */
@@ -655,10 +651,8 @@ DataStoreTLBMiss:
lis r1,PAGE_OFFSET@h /* check if kernel address */
cmplw 0,r1,r3
mfspr r2, SPRN_SPRG_603_PGDIR
- li r1,_PAGE_RW|_PAGE_USER|_PAGE_PRESENT /* access flags */
+ li r1, _PAGE_RW | _PAGE_PRESENT /* access flags */
bge- 112f
- mfspr r2,SPRN_SRR1 /* and MSR_PR bit from SRR1 */
- rlwimi r1,r2,32-12,29,29 /* shift MSR_PR to _PAGE_USER posn */
lis r2, (swapper_pg_dir - PAGE_OFFSET)@ha /* if kernel address, use */
addi r2, r2, (swapper_pg_dir - PAGE_OFFSET)@l /* kernel page table */
112: rlwimi r2,r3,12,20,29 /* insert top 10 bits of address */
--
2.13.3
For pages without _PAGE_USER, PP field is 00
For pages with _PAGE_USER, PP field is 10 for RW and 11 for RO.
This patch sets _PAGE_USER to 0x002 and _PAGE_RW to 0x001
is order to simplify TLB handling by reducing amount of shifts.
The location of _PAGE_PRESENT and _PAGE_HASHPTE doesn't matter
as they are only SW related flags.
Signed-off-by: Christophe Leroy <[email protected]>
---
arch/powerpc/include/asm/book3s/32/hash.h | 8 ++++----
arch/powerpc/kernel/head_32.S | 5 +----
arch/powerpc/mm/hash_low_32.S | 6 ++----
3 files changed, 7 insertions(+), 12 deletions(-)
diff --git a/arch/powerpc/include/asm/book3s/32/hash.h b/arch/powerpc/include/asm/book3s/32/hash.h
index 2a0a467d2985..a5907ea4fb40 100644
--- a/arch/powerpc/include/asm/book3s/32/hash.h
+++ b/arch/powerpc/include/asm/book3s/32/hash.h
@@ -17,9 +17,9 @@
* updating the accessed and modified bits in the page table tree.
*/
-#define _PAGE_PRESENT 0x001 /* software: pte contains a translation */
-#define _PAGE_HASHPTE 0x002 /* hash_page has made an HPTE for this pte */
-#define _PAGE_USER 0x004 /* usermode access allowed */
+#define _PAGE_RW 0x001 /* PP = x1: user write access allowed */
+#define _PAGE_USER 0x002 /* PP = 1x: usermode access allowed */
+#define _PAGE_HASHPTE 0x004 /* software: hash_page has made an HPTE for this pte */
#define _PAGE_GUARDED 0x008 /* G: prohibit speculative access */
#define _PAGE_COHERENT 0x010 /* M: enforce memory coherence (SMP systems) */
#define _PAGE_NO_CACHE 0x020 /* I: cache inhibit */
@@ -27,7 +27,7 @@
#define _PAGE_DIRTY 0x080 /* C: page changed */
#define _PAGE_ACCESSED 0x100 /* R: page referenced */
#define _PAGE_EXEC 0x200 /* software: exec allowed */
-#define _PAGE_RW 0x400 /* software: user write access allowed */
+#define _PAGE_PRESENT 0x400 /* software: pte contains a translation */
#define _PAGE_SPECIAL 0x800 /* software: Special page */
#ifdef CONFIG_PTE_64BIT
diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S
index 9f25f44b6448..3131fbd9e7f5 100644
--- a/arch/powerpc/kernel/head_32.S
+++ b/arch/powerpc/kernel/head_32.S
@@ -524,7 +524,6 @@ InstructionTLBMiss:
andc. r1,r1,r0 /* check access & ~permission */
bne- InstructionAddressInvalid /* return if access not permitted */
/* Convert linux-style PTE to low word of PPC-style PTE */
- rlwimi r0,r0,32-1,30,30 /* _PAGE_USER -> PP msb */
ori r1, r1, 0xe05 /* clear out reserved bits */
andc r1, r0, r1 /* PP = user? 2 : 0 */
BEGIN_FTR_SECTION
@@ -592,8 +591,7 @@ DataLoadTLBMiss:
* we would need to update the pte atomically with lwarx/stwcx.
*/
/* Convert linux-style PTE to low word of PPC-style PTE */
- rlwinm r1,r0,32-10,31,31 /* _PAGE_RW -> PP lsb */
- rlwimi r0,r0,32-1,30,30 /* _PAGE_USER -> PP msb */
+ rlwinm r1, r0, 0, 31, 31 /* _PAGE_RW -> PP lsb */
rlwimi r0,r0,32-1,31,31 /* _PAGE_USER -> PP lsb */
ori r1,r1,0xe04 /* clear out reserved bits */
andc r1,r0,r1 /* PP = user? rw? 2: 3: 0 */
@@ -672,7 +670,6 @@ DataStoreTLBMiss:
* we would need to update the pte atomically with lwarx/stwcx.
*/
/* Convert linux-style PTE to low word of PPC-style PTE */
- rlwimi r0,r0,32-1,30,30 /* _PAGE_USER -> PP msb */
li r1,0xe05 /* clear out reserved bits & PP lsb */
andc r1,r0,r1 /* PP = user? 2: 0 */
BEGIN_FTR_SECTION
diff --git a/arch/powerpc/mm/hash_low_32.S b/arch/powerpc/mm/hash_low_32.S
index 2afd0dce6d6a..ab60f541c4d2 100644
--- a/arch/powerpc/mm/hash_low_32.S
+++ b/arch/powerpc/mm/hash_low_32.S
@@ -311,11 +311,9 @@ Hash_msk = (((1 << Hash_bits) - 1) * 64)
_GLOBAL(create_hpte)
/* Convert linux-style PTE (r5) to low word of PPC-style PTE (r8) */
- rlwinm r8,r5,32-10,31,31 /* _PAGE_RW -> PP lsb */
rlwinm r0,r5,32-7,31,31 /* _PAGE_DIRTY -> PP lsb */
- and r8,r8,r0 /* writable if _RW & _DIRTY */
- rlwimi r5,r5,32-1,30,30 /* _PAGE_USER -> PP msb */
- rlwimi r5,r5,32-2,31,31 /* _PAGE_USER -> PP lsb */
+ and r8, r5, r0 /* writable if _RW & _DIRTY */
+ rlwimi r5, r5, 32 - 1, 31, 31 /* _PAGE_USER -> PP lsb */
ori r8,r8,0xe04 /* clear out reserved bits */
andc r8,r5,r8 /* PP = user? (rw&dirty? 2: 3): 0 */
BEGIN_FTR_SECTION
--
2.13.3
ITLB miss on kernel pages only occur with CONFIG_MODULES and
CONFIG_DEBUG_PAGEALLOC.
Signed-off-by: Christophe Leroy <[email protected]>
---
arch/powerpc/kernel/head_32.S | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S
index 53f65124edd5..3bbf937ad634 100644
--- a/arch/powerpc/kernel/head_32.S
+++ b/arch/powerpc/kernel/head_32.S
@@ -500,15 +500,19 @@ InstructionTLBMiss:
*/
/* Get PTE (linux-style) and check access */
mfspr r3,SPRN_IMISS
+#if defined(CONFIG_MODULES) || defined(CONFIG_DEBUG_PAGEALLOC)
lis r1,PAGE_OFFSET@h /* check if kernel address */
cmplw 0,r1,r3
+#endif
mfspr r2, SPRN_SPRG_603_PGDIR
li r1,_PAGE_USER|_PAGE_PRESENT|_PAGE_EXEC /* low addresses tested as user */
+#if defined(CONFIG_MODULES) || defined(CONFIG_DEBUG_PAGEALLOC)
bge- 112f
mfspr r2,SPRN_SRR1 /* and MSR_PR bit from SRR1 */
rlwimi r1,r2,32-12,29,29 /* shift MSR_PR to _PAGE_USER posn */
lis r2, (swapper_pg_dir - PAGE_OFFSET)@ha /* if kernel address, use */
addi r2, r2, (swapper_pg_dir - PAGE_OFFSET)@l /* kernel page table */
+#endif
112: rlwimi r2,r3,12,20,29 /* insert top 10 bits of address */
lwz r2,0(r2) /* get pmd entry */
rlwinm. r2,r2,0,0,19 /* extract address of pte page */
--
2.13.3
PAGE_ACCESSED is only needed for CONFIG_SWAP. When CONFIG_SWAP
is not set, just ignore it. If CONFIG_SWAP is set and PAGE_ACCESSED
is not, let's take a minor fault.
Signed-off-by: Christophe Leroy <[email protected]>
---
arch/powerpc/kernel/head_32.S | 24 +++++++++++++-----------
1 file changed, 13 insertions(+), 11 deletions(-)
diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S
index 44cc84857520..9f25f44b6448 100644
--- a/arch/powerpc/kernel/head_32.S
+++ b/arch/powerpc/kernel/head_32.S
@@ -505,7 +505,11 @@ InstructionTLBMiss:
cmplw 0,r1,r3
#endif
mfspr r2, SPRN_SPRG_603_PGDIR
+#ifdef CONFIG_SWAP
+ li r1,_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_EXEC
+#else
li r1,_PAGE_PRESENT | _PAGE_EXEC
+#endif
#if defined(CONFIG_MODULES) || defined(CONFIG_DEBUG_PAGEALLOC)
bge- 112f
lis r2, (swapper_pg_dir - PAGE_OFFSET)@ha /* if kernel address, use */
@@ -519,12 +523,6 @@ InstructionTLBMiss:
lwz r0,0(r2) /* get linux-style pte */
andc. r1,r1,r0 /* check access & ~permission */
bne- InstructionAddressInvalid /* return if access not permitted */
- ori r0,r0,_PAGE_ACCESSED /* set _PAGE_ACCESSED in pte */
- /*
- * NOTE! We are assuming this is not an SMP system, otherwise
- * we would need to update the pte atomically with lwarx/stwcx.
- */
- stw r0,0(r2) /* update PTE (accessed bit) */
/* Convert linux-style PTE to low word of PPC-style PTE */
rlwimi r0,r0,32-1,30,30 /* _PAGE_USER -> PP msb */
ori r1, r1, 0xe05 /* clear out reserved bits */
@@ -573,7 +571,11 @@ DataLoadTLBMiss:
lis r1,PAGE_OFFSET@h /* check if kernel address */
cmplw 0,r1,r3
mfspr r2, SPRN_SPRG_603_PGDIR
+#ifdef CONFIG_SWAP
+ li r1, _PAGE_PRESENT | _PAGE_ACCESSED
+#else
li r1, _PAGE_PRESENT
+#endif
bge- 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 */
@@ -585,12 +587,10 @@ DataLoadTLBMiss:
lwz r0,0(r2) /* get linux-style pte */
andc. r1,r1,r0 /* check access & ~permission */
bne- DataAddressInvalid /* return if access not permitted */
- ori r0,r0,_PAGE_ACCESSED /* set _PAGE_ACCESSED in pte */
/*
* NOTE! We are assuming this is not an SMP system, otherwise
* we would need to update the pte atomically with lwarx/stwcx.
*/
- stw r0,0(r2) /* update PTE (accessed bit) */
/* Convert linux-style PTE to low word of PPC-style PTE */
rlwinm r1,r0,32-10,31,31 /* _PAGE_RW -> PP lsb */
rlwimi r0,r0,32-1,30,30 /* _PAGE_USER -> PP msb */
@@ -651,7 +651,11 @@ DataStoreTLBMiss:
lis r1,PAGE_OFFSET@h /* check if kernel address */
cmplw 0,r1,r3
mfspr r2, SPRN_SPRG_603_PGDIR
- li r1, _PAGE_RW | _PAGE_PRESENT /* access flags */
+#ifdef CONFIG_SWAP
+ li r1, _PAGE_RW | _PAGE_PRESENT | _PAGE_ACCESSED
+#else
+ li r1, _PAGE_RW | _PAGE_PRESENT
+#endif
bge- 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 */
@@ -663,12 +667,10 @@ DataStoreTLBMiss:
lwz r0,0(r2) /* get linux-style pte */
andc. r1,r1,r0 /* check access & ~permission */
bne- DataAddressInvalid /* return if access not permitted */
- ori r0,r0,_PAGE_ACCESSED
/*
* NOTE! We are assuming this is not an SMP system, otherwise
* we would need to update the pte atomically with lwarx/stwcx.
*/
- stw r0,0(r2) /* update PTE (accessed/dirty bits) */
/* Convert linux-style PTE to low word of PPC-style PTE */
rlwimi r0,r0,32-1,30,30 /* _PAGE_USER -> PP msb */
li r1,0xe05 /* clear out reserved bits & PP lsb */
--
2.13.3
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 <[email protected]>
---
arch/powerpc/kernel/head_32.S | 15 ++++++---------
1 file changed, 6 insertions(+), 9 deletions(-)
diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S
index dbd15e03952a..53f65124edd5 100644
--- a/arch/powerpc/kernel/head_32.S
+++ b/arch/powerpc/kernel/head_32.S
@@ -507,9 +507,8 @@ InstructionTLBMiss:
bge- 112f
mfspr r2,SPRN_SRR1 /* and MSR_PR bit from SRR1 */
rlwimi r1,r2,32-12,29,29 /* shift MSR_PR to _PAGE_USER posn */
- lis r2,swapper_pg_dir@ha /* if kernel address, use */
- addi r2,r2,swapper_pg_dir@l /* kernel page table */
- tophys(r2,r2)
+ lis r2, (swapper_pg_dir - PAGE_OFFSET)@ha /* if kernel address, use */
+ addi r2, r2, (swapper_pg_dir - PAGE_OFFSET)@l /* kernel page table */
112: rlwimi r2,r3,12,20,29 /* insert top 10 bits of address */
lwz r2,0(r2) /* get pmd entry */
rlwinm. r2,r2,0,0,19 /* extract address of pte page */
@@ -580,9 +579,8 @@ DataLoadTLBMiss:
bge- 112f
mfspr r2,SPRN_SRR1 /* and MSR_PR bit from SRR1 */
rlwimi r1,r2,32-12,29,29 /* shift MSR_PR to _PAGE_USER posn */
- lis r2,swapper_pg_dir@ha /* if kernel address, use */
- addi r2,r2,swapper_pg_dir@l /* kernel page table */
- tophys(r2,r2)
+ lis r2, (swapper_pg_dir - PAGE_OFFSET)@ha /* if kernel address, use */
+ addi r2, r2, (swapper_pg_dir - PAGE_OFFSET)@l /* kernel page table */
112: rlwimi r2,r3,12,20,29 /* insert top 10 bits of address */
lwz r2,0(r2) /* get pmd entry */
rlwinm. r2,r2,0,0,19 /* extract address of pte page */
@@ -663,9 +661,8 @@ DataStoreTLBMiss:
bge- 112f
mfspr r2,SPRN_SRR1 /* and MSR_PR bit from SRR1 */
rlwimi r1,r2,32-12,29,29 /* shift MSR_PR to _PAGE_USER posn */
- lis r2,swapper_pg_dir@ha /* if kernel address, use */
- addi r2,r2,swapper_pg_dir@l /* kernel page table */
- tophys(r2,r2)
+ lis r2, (swapper_pg_dir - PAGE_OFFSET)@ha /* if kernel address, use */
+ addi r2, r2, (swapper_pg_dir - PAGE_OFFSET)@l /* kernel page table */
112: rlwimi r2,r3,12,20,29 /* insert top 10 bits of address */
lwz r2,0(r2) /* get pmd entry */
rlwinm. r2,r2,0,0,19 /* extract address of pte page */
--
2.13.3
_PAGE_RW and _PAGE_DIRTY do not matter for ITLB misses.
Signed-off-by: Christophe Leroy <[email protected]>
---
arch/powerpc/kernel/head_32.S | 8 ++------
1 file changed, 2 insertions(+), 6 deletions(-)
diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S
index 3bbf937ad634..2aec3f91c9f5 100644
--- a/arch/powerpc/kernel/head_32.S
+++ b/arch/powerpc/kernel/head_32.S
@@ -528,13 +528,9 @@ InstructionTLBMiss:
*/
stw r0,0(r2) /* update PTE (accessed bit) */
/* Convert linux-style PTE to low word of PPC-style PTE */
- rlwinm r1,r0,32-10,31,31 /* _PAGE_RW -> PP lsb */
- rlwinm r2,r0,32-7,31,31 /* _PAGE_DIRTY -> PP lsb */
- and r1,r1,r2 /* writable if _RW and _DIRTY */
rlwimi r0,r0,32-1,30,30 /* _PAGE_USER -> PP msb */
- rlwimi r0,r0,32-1,31,31 /* _PAGE_USER -> PP lsb */
- ori r1,r1,0xe04 /* clear out reserved bits */
- andc r1,r0,r1 /* PP = user? (rw&dirty? 2: 3): 0 */
+ ori r1, r1, 0xe05 /* clear out reserved bits */
+ andc r1, r0, r1 /* PP = user? 2 : 0 */
BEGIN_FTR_SECTION
rlwinm r1,r1,0,~_PAGE_COHERENT /* clear M (coherence not required) */
END_FTR_SECTION_IFCLR(CPU_FTR_NEED_COHERENT)
--
2.13.3
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 <[email protected]>
---
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
Le 25/01/2019 à 13:34, Christophe Leroy a écrit :
> Use SPRN_SPRG5 to store the current thread PGDIR and
> avoid reading thread_struct->pgdir at every TLB miss.
I'll send out v2 with an additional patch getting rid of SPRN_SPRG_RTAS
hence freeing SPRN_SPRG2 which I will use here instead of SPRN_SPRG5 so
that all 6xx will benefit.
Christophe
>
> Signed-off-by: Christophe Leroy <[email protected]>
> ---
> arch/powerpc/include/asm/reg.h | 1 +
> arch/powerpc/kernel/cpu_setup_6xx.S | 4 ++++
> arch/powerpc/kernel/head_32.S | 28 ++++++++++++++++------------
> 3 files changed, 21 insertions(+), 12 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h
> index 1c98ef1f2d5b..ba0ab1a1431b 100644
> --- a/arch/powerpc/include/asm/reg.h
> +++ b/arch/powerpc/include/asm/reg.h
> @@ -1169,6 +1169,7 @@
> #define SPRN_SPRG_SCRATCH1 SPRN_SPRG1
> #define SPRN_SPRG_RTAS SPRN_SPRG2
> #define SPRN_SPRG_603_LRU SPRN_SPRG4
> +#define SPRN_SPRG_603_PGDIR SPRN_SPRG5
> #endif
>
> #ifdef CONFIG_40x
> diff --git a/arch/powerpc/kernel/cpu_setup_6xx.S b/arch/powerpc/kernel/cpu_setup_6xx.S
> index 8c069e96c478..4c91d1f640fe 100644
> --- a/arch/powerpc/kernel/cpu_setup_6xx.S
> +++ b/arch/powerpc/kernel/cpu_setup_6xx.S
> @@ -24,6 +24,10 @@ BEGIN_MMU_FTR_SECTION
> li r10,0
> mtspr SPRN_SPRG_603_LRU,r10 /* init SW LRU tracking */
> END_MMU_FTR_SECTION_IFSET(MMU_FTR_NEED_DTLB_SW_LRU)
> + lis r10, (swapper_pg_dir - PAGE_OFFSET)@h
> + ori r10, r10, (swapper_pg_dir - PAGE_OFFSET)@l
> + mtspr SPRN_SPRG_603_PGDIR, r10
> +
> BEGIN_FTR_SECTION
> bl __init_fpu_registers
> END_FTR_SECTION_IFCLR(CPU_FTR_FPU_UNAVAILABLE)
> diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S
> index c2f564690778..dbd15e03952a 100644
> --- a/arch/powerpc/kernel/head_32.S
> +++ b/arch/powerpc/kernel/head_32.S
> @@ -502,16 +502,15 @@ InstructionTLBMiss:
> mfspr r3,SPRN_IMISS
> lis r1,PAGE_OFFSET@h /* check if kernel address */
> cmplw 0,r1,r3
> - mfspr r2,SPRN_SPRG_THREAD
> + mfspr r2, SPRN_SPRG_603_PGDIR
> li r1,_PAGE_USER|_PAGE_PRESENT|_PAGE_EXEC /* low addresses tested as user */
> - lwz r2,PGDIR(r2)
> bge- 112f
> mfspr r2,SPRN_SRR1 /* and MSR_PR bit from SRR1 */
> rlwimi r1,r2,32-12,29,29 /* shift MSR_PR to _PAGE_USER posn */
> lis r2,swapper_pg_dir@ha /* if kernel address, use */
> addi r2,r2,swapper_pg_dir@l /* kernel page table */
> -112: tophys(r2,r2)
> - rlwimi r2,r3,12,20,29 /* insert top 10 bits of address */
> + tophys(r2,r2)
> +112: rlwimi r2,r3,12,20,29 /* insert top 10 bits of address */
> lwz r2,0(r2) /* get pmd entry */
> rlwinm. r2,r2,0,0,19 /* extract address of pte page */
> beq- InstructionAddressInvalid /* return if no mapping */
> @@ -576,16 +575,15 @@ DataLoadTLBMiss:
> mfspr r3,SPRN_DMISS
> lis r1,PAGE_OFFSET@h /* check if kernel address */
> cmplw 0,r1,r3
> - mfspr r2,SPRN_SPRG_THREAD
> + mfspr r2, SPRN_SPRG_603_PGDIR
> li r1,_PAGE_USER|_PAGE_PRESENT /* low addresses tested as user */
> - lwz r2,PGDIR(r2)
> bge- 112f
> mfspr r2,SPRN_SRR1 /* and MSR_PR bit from SRR1 */
> rlwimi r1,r2,32-12,29,29 /* shift MSR_PR to _PAGE_USER posn */
> lis r2,swapper_pg_dir@ha /* if kernel address, use */
> addi r2,r2,swapper_pg_dir@l /* kernel page table */
> -112: tophys(r2,r2)
> - rlwimi r2,r3,12,20,29 /* insert top 10 bits of address */
> + tophys(r2,r2)
> +112: rlwimi r2,r3,12,20,29 /* insert top 10 bits of address */
> lwz r2,0(r2) /* get pmd entry */
> rlwinm. r2,r2,0,0,19 /* extract address of pte page */
> beq- DataAddressInvalid /* return if no mapping */
> @@ -660,16 +658,15 @@ DataStoreTLBMiss:
> mfspr r3,SPRN_DMISS
> lis r1,PAGE_OFFSET@h /* check if kernel address */
> cmplw 0,r1,r3
> - mfspr r2,SPRN_SPRG_THREAD
> + mfspr r2, SPRN_SPRG_603_PGDIR
> li r1,_PAGE_RW|_PAGE_USER|_PAGE_PRESENT /* access flags */
> - lwz r2,PGDIR(r2)
> bge- 112f
> mfspr r2,SPRN_SRR1 /* and MSR_PR bit from SRR1 */
> rlwimi r1,r2,32-12,29,29 /* shift MSR_PR to _PAGE_USER posn */
> lis r2,swapper_pg_dir@ha /* if kernel address, use */
> addi r2,r2,swapper_pg_dir@l /* kernel page table */
> -112: tophys(r2,r2)
> - rlwimi r2,r3,12,20,29 /* insert top 10 bits of address */
> + tophys(r2,r2)
> +112: rlwimi r2,r3,12,20,29 /* insert top 10 bits of address */
> lwz r2,0(r2) /* get pmd entry */
> rlwinm. r2,r2,0,0,19 /* extract address of pte page */
> beq- DataAddressInvalid /* return if no mapping */
> @@ -1030,6 +1027,13 @@ _ENTRY(switch_mmu_context)
> 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_603_PGDIR, r4
> +END_MMU_FTR_SECTION_IFCLR(MMU_FTR_HPTE_TABLE)
> li r4,0
> isync
> 3:
>
On Fri, 2019-01-25 at 12:34:20 UTC, Christophe Leroy wrote:
> For pages without _PAGE_USER, PP field is 00
> For pages with _PAGE_USER, PP field is 10 for RW and 11 for RO.
>
> This patch sets _PAGE_USER to 0x002 and _PAGE_RW to 0x001
> is order to simplify TLB handling by reducing amount of shifts.
>
> The location of _PAGE_PRESENT and _PAGE_HASHPTE doesn't matter
> as they are only SW related flags.
>
> Signed-off-by: Christophe Leroy <[email protected]>
Applied to powerpc next, thanks.
https://git.kernel.org/powerpc/c/78ca1108b10927b3d068c8da91352b0f
cheers