From 8ad200d7b7c8fac77cf705831e90e889360d7030 Mon Sep 17 00:00:00 2001
From: Paul Mackerras <paulus@samba.org>
Date: Fri, 4 Nov 2005 13:28:58 +1100
Subject: [PATCH] powerpc: Merge smp-tbsync.c (the generic timebase sync
routine)
Signed-off-by: Paul Mackerras <paulus@samba.org>
---
arch/powerpc/Kconfig | 7 ++
arch/powerpc/kernel/Makefile | 1 +
arch/{ppc64 => powerpc}/kernel/smp-tbsync.c | 110 +++++++++-----------
arch/ppc64/Kconfig | 5 +
arch/ppc64/kernel/Makefile | 5 -
5 files changed, 64 insertions(+), 64 deletions(-)
rename arch/{ppc64 => powerpc}/kernel/smp-tbsync.c (52%)
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 3cf03ab46113..f4e25c648fbb 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -300,6 +300,7 @@ config PPC_PMAC64
bool
depends on PPC_PMAC && POWER4
select U3_DART
+ select GENERIC_TBSYNC
default y
config PPC_PREP
@@ -314,6 +315,7 @@ config PPC_MAPLE
bool " Maple 970FX Evaluation Board"
select U3_DART
select MPIC_BROKEN_U3
+ select GENERIC_TBSYNC
default n
help
This option enables support for the Maple 970FX Evaluation Board.
@@ -386,6 +388,11 @@ config PPC_MPC106
bool
default n
+config GENERIC_TBSYNC
+ bool
+ default y if CONFIG_PPC32 && CONFIG_SMP
+ default n
+
source "drivers/cpufreq/Kconfig"
config CPU_FREQ_PMAC
diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
index 7a3e1155ac9a..631149ea93db 100644
--- a/arch/powerpc/kernel/Makefile
+++ b/arch/powerpc/kernel/Makefile
@@ -21,6 +21,7 @@ obj-$(CONFIG_PPC_RTAS) += rtas.o
obj-$(CONFIG_RTAS_FLASH) += rtas_flash.o
obj-$(CONFIG_RTAS_PROC) += rtas-proc.o
obj-$(CONFIG_IBMVIO) += vio.o
+obj-$(CONFIG_GENERIC_TBSYNC) += smp-tbsync.o
ifeq ($(CONFIG_PPC_MERGE),y)
diff --git a/arch/ppc64/kernel/smp-tbsync.c b/arch/powerpc/kernel/smp-tbsync.c
similarity index 52%
rename from arch/ppc64/kernel/smp-tbsync.c
rename to arch/powerpc/kernel/smp-tbsync.c
index 7d8ec9996b3e..9adef3bddad4 100644
--- a/arch/ppc64/kernel/smp-tbsync.c
+++ b/arch/powerpc/kernel/smp-tbsync.c
@@ -22,11 +22,11 @@ enum {
};
static struct {
- volatile long tb;
- volatile long mark;
+ volatile u64 tb;
+ volatile u64 mark;
volatile int cmd;
volatile int handshake;
- int filler[3];
+ int filler[2];
volatile int ack;
int filler2[7];
@@ -36,89 +36,80 @@ static struct {
static volatile int running;
-static void __devinit
-enter_contest( long mark, long add )
+static void __devinit enter_contest(u64 mark, long add)
{
- while( (long)(mftb() - mark) < 0 )
+ while (get_tb() < mark)
tbsync->race_result = add;
}
-void __devinit
-smp_generic_take_timebase( void )
+void __devinit smp_generic_take_timebase(void)
{
int cmd;
- long tb;
+ u64 tb;
local_irq_disable();
- while( !running )
- ;
+ while (!running)
+ barrier();
rmb();
- for( ;; ) {
+ for (;;) {
tbsync->ack = 1;
- while( !tbsync->handshake )
- ;
+ while (!tbsync->handshake)
+ barrier();
rmb();
cmd = tbsync->cmd;
tb = tbsync->tb;
+ mb();
tbsync->ack = 0;
- if( cmd == kExit )
- return;
+ if (cmd == kExit)
+ break;
- if( cmd == kSetAndTest ) {
- while( tbsync->handshake )
- ;
- asm volatile ("mttbl %0" :: "r" (tb & 0xfffffffful) );
- asm volatile ("mttbu %0" :: "r" (tb >> 32) );
- } else {
- while( tbsync->handshake )
- ;
- }
- enter_contest( tbsync->mark, -1 );
+ while (tbsync->handshake)
+ barrier();
+ if (cmd == kSetAndTest)
+ set_tb(tb >> 32, tb & 0xfffffffful);
+ enter_contest(tbsync->mark, -1);
}
local_irq_enable();
}
-static int __devinit
-start_contest( int cmd, long offset, long num )
+static int __devinit start_contest(int cmd, long offset, int num)
{
int i, score=0;
- long tb, mark;
+ u64 tb;
+ long mark;
tbsync->cmd = cmd;
local_irq_disable();
- for( i=-3; i<num; ) {
- tb = (long)mftb() + 400;
+ for (i = -3; i < num; ) {
+ tb = get_tb() + 400;
tbsync->tb = tb + offset;
tbsync->mark = mark = tb + 400;
wmb();
tbsync->handshake = 1;
- while( tbsync->ack )
- ;
+ while (tbsync->ack)
+ barrier();
- while( (long)(mftb() - tb) <= 0 )
- ;
+ while (get_tb() <= tb)
+ barrier();
tbsync->handshake = 0;
- enter_contest( mark, 1 );
+ enter_contest(mark, 1);
- while( !tbsync->ack )
- ;
+ while (!tbsync->ack)
+ barrier();
- if ((tbsync->tb ^ (long)mftb()) & 0x8000000000000000ul)
- continue;
- if( i++ > 0 )
+ if (i++ > 0)
score += tbsync->race_result;
}
local_irq_enable();
return score;
}
-void __devinit
-smp_generic_give_timebase( void )
+void __devinit smp_generic_give_timebase(void)
{
int i, score, score2, old, min=0, max=5000, offset=1000;
@@ -130,14 +121,14 @@ smp_generic_give_timebase( void )
mb();
running = 1;
- while( !tbsync->ack )
- ;
+ while (!tbsync->ack)
+ barrier();
printk("Got ack\n");
/* binary search */
- for( old=-1 ; old != offset ; offset=(min+max)/2 ) {
- score = start_contest( kSetAndTest, offset, NUM_ITER );
+ for (old = -1; old != offset ; offset = (min+max) / 2) {
+ score = start_contest(kSetAndTest, offset, NUM_ITER);
printk("score %d, offset %d\n", score, offset );
@@ -147,21 +138,22 @@ smp_generic_give_timebase( void )
min = offset;
old = offset;
}
- score = start_contest( kSetAndTest, min, NUM_ITER );
- score2 = start_contest( kSetAndTest, max, NUM_ITER );
+ score = start_contest(kSetAndTest, min, NUM_ITER);
+ score2 = start_contest(kSetAndTest, max, NUM_ITER);
- printk( "Min %d (score %d), Max %d (score %d)\n", min, score, max, score2 );
- score = abs( score );
- score2 = abs( score2 );
+ printk("Min %d (score %d), Max %d (score %d)\n",
+ min, score, max, score2);
+ score = abs(score);
+ score2 = abs(score2);
offset = (score < score2) ? min : max;
/* guard against inaccurate mttb */
- for( i=0; i<10; i++ ) {
- start_contest( kSetAndTest, offset, NUM_ITER/10 );
+ for (i = 0; i < 10; i++) {
+ start_contest(kSetAndTest, offset, NUM_ITER/10);
- if( (score2=start_contest(kTest, offset, NUM_ITER)) < 0 )
+ if ((score2 = start_contest(kTest, offset, NUM_ITER)) < 0)
score2 = -score2;
- if( score2 <= score || score2 < 20 )
+ if (score2 <= score || score2 < 20)
break;
}
printk("Final offset: %d (%d/%d)\n", offset, score2, NUM_ITER );
@@ -170,10 +162,10 @@ smp_generic_give_timebase( void )
tbsync->cmd = kExit;
wmb();
tbsync->handshake = 1;
- while( tbsync->ack )
- ;
+ while (tbsync->ack)
+ barrier();
tbsync->handshake = 0;
- kfree( tbsync );
+ kfree(tbsync);
tbsync = NULL;
running = 0;
}
diff --git a/arch/ppc64/Kconfig b/arch/ppc64/Kconfig
index 42677cc96508..b987164fca4c 100644
--- a/arch/ppc64/Kconfig
+++ b/arch/ppc64/Kconfig
@@ -89,12 +89,14 @@ config PPC_PMAC
bool " Apple G5 based machines"
default y
select U3_DART
+ select GENERIC_TBSYNC
config PPC_MAPLE
depends on PPC_MULTIPLATFORM
bool " Maple 970FX Evaluation Board"
select U3_DART
select MPIC_BROKEN_U3
+ select GENERIC_TBSYNC
default n
help
This option enables support for the Maple 970FX Evaluation Board.
@@ -182,6 +184,9 @@ config MPIC_BROKEN_U3
depends on PPC_MAPLE
default y
+config GENERIC_TBSYNC
+ def_bool n
+
config PPC_PMAC64
bool
depends on PPC_PMAC
diff --git a/arch/ppc64/kernel/Makefile b/arch/ppc64/kernel/Makefile
index 430cb3900a07..f597c2954b71 100644
--- a/arch/ppc64/kernel/Makefile
+++ b/arch/ppc64/kernel/Makefile
@@ -51,11 +51,6 @@ obj-$(CONFIG_PPC_PMAC) += udbg_scc.o
obj-$(CONFIG_PPC_MAPLE) += udbg_16550.o
-ifdef CONFIG_SMP
-obj-$(CONFIG_PPC_PMAC) += smp-tbsync.o
-obj-$(CONFIG_PPC_MAPLE) += smp-tbsync.o
-endif
-
obj-$(CONFIG_KPROBES) += kprobes.o
CFLAGS_ioctl32.o += -Ifs/