* [PATCH 4/4] 8xx: Use SPRG2 and DAR registers to stash r11 and cr.
2010-02-26 8:29 ` [PATCH 3/4] 8xx: Don't touch ACCESSED when no SWAP Joakim Tjernlund
@ 2010-02-26 8:29 ` Joakim Tjernlund
0 siblings, 0 replies; 6+ messages in thread
From: Joakim Tjernlund @ 2010-02-26 8:29 UTC (permalink / raw)
To: linuxppc-dev
This avoids storing these registers in memory.
CPU6 errata will still use the old way.
Remove some G2 leftover accesses from 2.4
---
arch/powerpc/kernel/head_8xx.S | 49 +++++++++++++++++++++++++++++----------
1 files changed, 36 insertions(+), 13 deletions(-)
diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index 6478a96..1f1a04b 100644
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -71,9 +71,6 @@ _ENTRY(_start);
* in the first level table, but that would require many changes to the
* Linux page directory/table functions that I don't want to do right now.
*
- * I used to use SPRG2 for a temporary register in the TLB handler, but it
- * has since been put to other uses. I now use a hack to save a register
- * and the CCR at memory location 0.....Someday I'll fix this.....
* -- Dan
*/
.globl __start
@@ -302,8 +299,13 @@ InstructionTLBMiss:
DO_8xx_CPU6(0x3f80, r3)
mtspr SPRN_M_TW, r10 /* Save a couple of working registers */
mfcr r10
+#ifdef CONFIG_8xx_CPU6
stw r10, 0(r0)
stw r11, 4(r0)
+#else
+ mtspr SPRN_DAR, r10
+ mtspr SPRN_SPRG2, r11
+#endif
mfspr r10, SPRN_SRR0 /* Get effective address of fault */
#ifdef CONFIG_8xx_CPU15
addi r11, r10, 0x1000
@@ -359,13 +361,19 @@ InstructionTLBMiss:
DO_8xx_CPU6(0x2d80, r3)
mtspr SPRN_MI_RPN, r10 /* Update TLB entry */
- mfspr r10, SPRN_M_TW /* Restore registers */
+ /* Restore registers */
+#ifndef CONFIG_8xx_CPU6
+ mfspr r10, SPRN_DAR
+ mtcr r10
+ mtspr SPRN_DAR, r11 /* Tag DAR */
+ mfspr r11, SPRN_SPRG2
+#else
lwz r11, 0(r0)
mtcr r11
lwz r11, 4(r0)
-#ifdef CONFIG_8xx_CPU6
lwz r3, 8(r0)
#endif
+ mfspr r10, SPRN_M_TW
rfi
2:
mfspr r11, SPRN_SRR1
@@ -375,13 +383,20 @@ InstructionTLBMiss:
rlwinm r11, r11, 0, 0xffff
mtspr SPRN_SRR1, r11
- mfspr r10, SPRN_M_TW /* Restore registers */
+ /* Restore registers */
+#ifndef CONFIG_8xx_CPU6
+ mfspr r10, SPRN_DAR
+ mtcr r10
+ li r11, 0x00f0
+ mtspr SPRN_DAR, r11 /* Tag DAR */
+ mfspr r11, SPRN_SPRG2
+#else
lwz r11, 0(r0)
mtcr r11
lwz r11, 4(r0)
-#ifdef CONFIG_8xx_CPU6
lwz r3, 8(r0)
#endif
+ mfspr r10, SPRN_M_TW
b InstructionAccess
. = 0x1200
@@ -392,8 +407,13 @@ DataStoreTLBMiss:
DO_8xx_CPU6(0x3f80, r3)
mtspr SPRN_M_TW, r10 /* Save a couple of working registers */
mfcr r10
+#ifdef CONFIG_8xx_CPU6
stw r10, 0(r0)
stw r11, 4(r0)
+#else
+ mtspr SPRN_DAR, r10
+ mtspr SPRN_SPRG2, r11
+#endif
mfspr r10, SPRN_M_TWB /* Get level 1 table entry address */
/* If we are faulting a kernel address, we have to use the
@@ -461,18 +481,24 @@ DataStoreTLBMiss:
* of the MMU.
*/
2: li r11, 0x00f0
- mtspr SPRN_DAR,r11 /* Tag DAR */
rlwimi r10, r11, 0, 24, 28 /* Set 24-27, clear 28 */
DO_8xx_CPU6(0x3d80, r3)
mtspr SPRN_MD_RPN, r10 /* Update TLB entry */
- mfspr r10, SPRN_M_TW /* Restore registers */
+ /* Restore registers */
+#ifndef CONFIG_8xx_CPU6
+ mfspr r10, SPRN_DAR
+ mtcr r10
+ mtspr SPRN_DAR, r11 /* Tag DAR */
+ mfspr r11, SPRN_SPRG2
+#else
+ mtspr SPRN_DAR, r11 /* Tag DAR */
lwz r11, 0(r0)
mtcr r11
lwz r11, 4(r0)
-#ifdef CONFIG_8xx_CPU6
lwz r3, 8(r0)
#endif
+ mfspr r10, SPRN_M_TW
rfi
/* This is an instruction TLB error on the MPC8xx. This could be due
@@ -684,9 +710,6 @@ start_here:
tophys(r4,r2)
addi r4,r4,THREAD /* init task's THREAD */
mtspr SPRN_SPRG_THREAD,r4
- li r3,0
- /* XXX What is that for ? SPRG2 appears otherwise unused on 8xx */
- mtspr SPRN_SPRG2,r3 /* 0 => r1 has kernel sp */
/* stack */
lis r1,init_thread_union@ha
--
1.6.4.4
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH 0/4] 8xx: Optimize TLB Miss code.
@ 2010-03-02 15:37 Joakim Tjernlund
2010-03-02 15:37 ` [PATCH 1/4] 8xx: Optimze TLB Miss handlers Joakim Tjernlund
0 siblings, 1 reply; 6+ messages in thread
From: Joakim Tjernlund @ 2010-03-02 15:37 UTC (permalink / raw)
To: linuxppc-dev, Scott Wood
This set of tries to optimize the TLB code on 8xx even
more. If they work, it should be a noticable performance
boost.
I would be very happy if you could test them for me.
- v2:
Since Scott has done some testing of these patches I resend
them with my SOB.
Scott, can you "bless" these patches too?
Joakim Tjernlund (4):
8xx: Optimze TLB Miss handlers
8xx: Avoid testing for kernel space in ITLB Miss.
8xx: Don't touch ACCESSED when no SWAP.
8xx: Use SPRG2 and DAR registers to stash r11 and cr.
arch/powerpc/kernel/head_8xx.S | 70 +++++++++++++++++++++++++++-------------
1 files changed, 47 insertions(+), 23 deletions(-)
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH 1/4] 8xx: Optimze TLB Miss handlers
2010-03-02 15:37 [PATCH 0/4] 8xx: Optimize TLB Miss code Joakim Tjernlund
@ 2010-03-02 15:37 ` Joakim Tjernlund
2010-03-02 15:37 ` [PATCH 2/4] 8xx: Avoid testing for kernel space in ITLB Miss Joakim Tjernlund
0 siblings, 1 reply; 6+ messages in thread
From: Joakim Tjernlund @ 2010-03-02 15:37 UTC (permalink / raw)
To: linuxppc-dev, Scott Wood
This removes a couple of insn's from the TLB Miss
handlers whithout changing functionality.
Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
---
arch/powerpc/kernel/head_8xx.S | 11 +++--------
1 files changed, 3 insertions(+), 8 deletions(-)
diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index 3ef743f..ecc4a02 100644
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -343,17 +343,14 @@ InstructionTLBMiss:
cmpwi cr0, r11, _PAGE_ACCESSED | _PAGE_PRESENT
bne- cr0, 2f
- /* Clear PP lsb, 0x400 */
- rlwinm r10, r10, 0, 22, 20
-
/* The Linux PTE won't go exactly into the MMU TLB.
- * Software indicator bits 22 and 28 must be clear.
+ * Software indicator bits 21 and 28 must be clear.
* Software indicator bits 24, 25, 26, and 27 must be
* set. All other Linux PTE bits control the behavior
* of the MMU.
*/
li r11, 0x00f0
- rlwimi r10, r11, 0, 24, 28 /* Set 24-27, clear 28 */
+ rlwimi r10, r11, 0, 0x07f8 /* Set 24-27, clear 21-23,28 */
DO_8xx_CPU6(0x2d80, r3)
mtspr SPRN_MI_RPN, r10 /* Update TLB entry */
@@ -444,9 +441,7 @@ DataStoreTLBMiss:
/* Honour kernel RO, User NA */
/* 0x200 == Extended encoding, bit 22 */
- /* r11 = (r10 & _PAGE_USER) >> 2 */
- rlwinm r11, r10, 32-2, 0x200
- or r10, r11, r10
+ rlwimi r10, r10, 32-2, 0x200 /* Copy USER to bit 22, 0x200 */
/* r11 = (r10 & _PAGE_RW) >> 1 */
rlwinm r11, r10, 32-1, 0x200
or r10, r11, r10
--
1.6.4.4
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH 2/4] 8xx: Avoid testing for kernel space in ITLB Miss.
2010-03-02 15:37 ` [PATCH 1/4] 8xx: Optimze TLB Miss handlers Joakim Tjernlund
@ 2010-03-02 15:37 ` Joakim Tjernlund
2010-03-02 15:37 ` [PATCH 3/4] 8xx: Don't touch ACCESSED when no SWAP Joakim Tjernlund
0 siblings, 1 reply; 6+ messages in thread
From: Joakim Tjernlund @ 2010-03-02 15:37 UTC (permalink / raw)
To: linuxppc-dev, Scott Wood
Only modules will cause ITLB Misses as we always pin
the first 8MB of kernel memory.
Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
---
arch/powerpc/kernel/head_8xx.S | 4 ++++
1 files changed, 4 insertions(+), 0 deletions(-)
diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index ecc4a02..84ca1d9 100644
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -318,12 +318,16 @@ InstructionTLBMiss:
/* If we are faulting a kernel address, we have to use the
* kernel page tables.
*/
+#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 */
beq 3f
lis r11, swapper_pg_dir@h
ori r11, r11, swapper_pg_dir@l
rlwimi r10, r11, 0, 2, 19
3:
+#endif
lwz r11, 0(r10) /* 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 */
--
1.6.4.4
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH 3/4] 8xx: Don't touch ACCESSED when no SWAP.
2010-03-02 15:37 ` [PATCH 2/4] 8xx: Avoid testing for kernel space in ITLB Miss Joakim Tjernlund
@ 2010-03-02 15:37 ` Joakim Tjernlund
2010-03-02 15:37 ` [PATCH 4/4] 8xx: Use SPRG2 and DAR registers to stash r11 and cr Joakim Tjernlund
0 siblings, 1 reply; 6+ messages in thread
From: Joakim Tjernlund @ 2010-03-02 15:37 UTC (permalink / raw)
To: linuxppc-dev, Scott Wood
Only the swap function cares about the ACCESSED bit in
the pte. Do not waste cycles updateting ACCESSED when swap
is not compiled into the kernel.
Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
---
arch/powerpc/kernel/head_8xx.S | 6 ++++--
1 files changed, 4 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index 84ca1d9..6478a96 100644
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -343,10 +343,11 @@ InstructionTLBMiss:
mfspr r11, SPRN_MD_TWC /* ....and get the pte address */
lwz r10, 0(r11) /* Get the pte */
+#ifdef CONFIG_SWAP
andi. r11, r10, _PAGE_ACCESSED | _PAGE_PRESENT
cmpwi cr0, r11, _PAGE_ACCESSED | _PAGE_PRESENT
bne- cr0, 2f
-
+#endif
/* The Linux PTE won't go exactly into the MMU TLB.
* Software indicator bits 21 and 28 must be clear.
* Software indicator bits 24, 25, 26, and 27 must be
@@ -439,10 +440,11 @@ DataStoreTLBMiss:
* r11 = ((r10 & PRESENT) & ((r10 & ACCESSED) >> 5));
* r10 = (r10 & ~PRESENT) | r11;
*/
+#ifdef CONFIG_SWAP
rlwinm r11, r10, 32-5, _PAGE_PRESENT
and r11, r11, r10
rlwimi r10, r11, 0, _PAGE_PRESENT
-
+#endif
/* Honour kernel RO, User NA */
/* 0x200 == Extended encoding, bit 22 */
rlwimi r10, r10, 32-2, 0x200 /* Copy USER to bit 22, 0x200 */
--
1.6.4.4
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH 4/4] 8xx: Use SPRG2 and DAR registers to stash r11 and cr.
2010-03-02 15:37 ` [PATCH 3/4] 8xx: Don't touch ACCESSED when no SWAP Joakim Tjernlund
@ 2010-03-02 15:37 ` Joakim Tjernlund
0 siblings, 0 replies; 6+ messages in thread
From: Joakim Tjernlund @ 2010-03-02 15:37 UTC (permalink / raw)
To: linuxppc-dev, Scott Wood
This avoids storing these registers in memory.
CPU6 errata will still use the old way.
Remove some G2 leftover accesses from 2.4
Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
---
arch/powerpc/kernel/head_8xx.S | 49 +++++++++++++++++++++++++++++----------
1 files changed, 36 insertions(+), 13 deletions(-)
diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index 6478a96..1f1a04b 100644
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -71,9 +71,6 @@ _ENTRY(_start);
* in the first level table, but that would require many changes to the
* Linux page directory/table functions that I don't want to do right now.
*
- * I used to use SPRG2 for a temporary register in the TLB handler, but it
- * has since been put to other uses. I now use a hack to save a register
- * and the CCR at memory location 0.....Someday I'll fix this.....
* -- Dan
*/
.globl __start
@@ -302,8 +299,13 @@ InstructionTLBMiss:
DO_8xx_CPU6(0x3f80, r3)
mtspr SPRN_M_TW, r10 /* Save a couple of working registers */
mfcr r10
+#ifdef CONFIG_8xx_CPU6
stw r10, 0(r0)
stw r11, 4(r0)
+#else
+ mtspr SPRN_DAR, r10
+ mtspr SPRN_SPRG2, r11
+#endif
mfspr r10, SPRN_SRR0 /* Get effective address of fault */
#ifdef CONFIG_8xx_CPU15
addi r11, r10, 0x1000
@@ -359,13 +361,19 @@ InstructionTLBMiss:
DO_8xx_CPU6(0x2d80, r3)
mtspr SPRN_MI_RPN, r10 /* Update TLB entry */
- mfspr r10, SPRN_M_TW /* Restore registers */
+ /* Restore registers */
+#ifndef CONFIG_8xx_CPU6
+ mfspr r10, SPRN_DAR
+ mtcr r10
+ mtspr SPRN_DAR, r11 /* Tag DAR */
+ mfspr r11, SPRN_SPRG2
+#else
lwz r11, 0(r0)
mtcr r11
lwz r11, 4(r0)
-#ifdef CONFIG_8xx_CPU6
lwz r3, 8(r0)
#endif
+ mfspr r10, SPRN_M_TW
rfi
2:
mfspr r11, SPRN_SRR1
@@ -375,13 +383,20 @@ InstructionTLBMiss:
rlwinm r11, r11, 0, 0xffff
mtspr SPRN_SRR1, r11
- mfspr r10, SPRN_M_TW /* Restore registers */
+ /* Restore registers */
+#ifndef CONFIG_8xx_CPU6
+ mfspr r10, SPRN_DAR
+ mtcr r10
+ li r11, 0x00f0
+ mtspr SPRN_DAR, r11 /* Tag DAR */
+ mfspr r11, SPRN_SPRG2
+#else
lwz r11, 0(r0)
mtcr r11
lwz r11, 4(r0)
-#ifdef CONFIG_8xx_CPU6
lwz r3, 8(r0)
#endif
+ mfspr r10, SPRN_M_TW
b InstructionAccess
. = 0x1200
@@ -392,8 +407,13 @@ DataStoreTLBMiss:
DO_8xx_CPU6(0x3f80, r3)
mtspr SPRN_M_TW, r10 /* Save a couple of working registers */
mfcr r10
+#ifdef CONFIG_8xx_CPU6
stw r10, 0(r0)
stw r11, 4(r0)
+#else
+ mtspr SPRN_DAR, r10
+ mtspr SPRN_SPRG2, r11
+#endif
mfspr r10, SPRN_M_TWB /* Get level 1 table entry address */
/* If we are faulting a kernel address, we have to use the
@@ -461,18 +481,24 @@ DataStoreTLBMiss:
* of the MMU.
*/
2: li r11, 0x00f0
- mtspr SPRN_DAR,r11 /* Tag DAR */
rlwimi r10, r11, 0, 24, 28 /* Set 24-27, clear 28 */
DO_8xx_CPU6(0x3d80, r3)
mtspr SPRN_MD_RPN, r10 /* Update TLB entry */
- mfspr r10, SPRN_M_TW /* Restore registers */
+ /* Restore registers */
+#ifndef CONFIG_8xx_CPU6
+ mfspr r10, SPRN_DAR
+ mtcr r10
+ mtspr SPRN_DAR, r11 /* Tag DAR */
+ mfspr r11, SPRN_SPRG2
+#else
+ mtspr SPRN_DAR, r11 /* Tag DAR */
lwz r11, 0(r0)
mtcr r11
lwz r11, 4(r0)
-#ifdef CONFIG_8xx_CPU6
lwz r3, 8(r0)
#endif
+ mfspr r10, SPRN_M_TW
rfi
/* This is an instruction TLB error on the MPC8xx. This could be due
@@ -684,9 +710,6 @@ start_here:
tophys(r4,r2)
addi r4,r4,THREAD /* init task's THREAD */
mtspr SPRN_SPRG_THREAD,r4
- li r3,0
- /* XXX What is that for ? SPRG2 appears otherwise unused on 8xx */
- mtspr SPRN_SPRG2,r3 /* 0 => r1 has kernel sp */
/* stack */
lis r1,init_thread_union@ha
--
1.6.4.4
^ permalink raw reply related [flat|nested] 6+ messages in thread
end of thread, other threads:[~2010-03-02 15:37 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2010-03-02 15:37 [PATCH 0/4] 8xx: Optimize TLB Miss code Joakim Tjernlund
2010-03-02 15:37 ` [PATCH 1/4] 8xx: Optimze TLB Miss handlers Joakim Tjernlund
2010-03-02 15:37 ` [PATCH 2/4] 8xx: Avoid testing for kernel space in ITLB Miss Joakim Tjernlund
2010-03-02 15:37 ` [PATCH 3/4] 8xx: Don't touch ACCESSED when no SWAP Joakim Tjernlund
2010-03-02 15:37 ` [PATCH 4/4] 8xx: Use SPRG2 and DAR registers to stash r11 and cr Joakim Tjernlund
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2010-02-26 8:29 [PATCH 0/4] 8xx: Optimize TLB Miss code Joakim Tjernlund
2010-02-26 8:29 ` [PATCH 1/4] 8xx: Optimze TLB Miss handlers Joakim Tjernlund
2010-02-26 8:29 ` [PATCH 2/4] 8xx: Avoid testing for kernel space in ITLB Miss Joakim Tjernlund
2010-02-26 8:29 ` [PATCH 3/4] 8xx: Don't touch ACCESSED when no SWAP Joakim Tjernlund
2010-02-26 8:29 ` [PATCH 4/4] 8xx: Use SPRG2 and DAR registers to stash r11 and cr Joakim Tjernlund
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