powerpc: Merge smp-tbsync.c (the generic timebase sync routine)
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 3cf03ab..f4e25c6 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -300,6 +300,7 @@
bool
depends on PPC_PMAC && POWER4
select U3_DART
+ select GENERIC_TBSYNC
default y
config PPC_PREP
@@ -314,6 +315,7 @@
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 @@
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 7a3e115..631149ea 100644
--- a/arch/powerpc/kernel/Makefile
+++ b/arch/powerpc/kernel/Makefile
@@ -21,6 +21,7 @@
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/powerpc/kernel/smp-tbsync.c b/arch/powerpc/kernel/smp-tbsync.c
new file mode 100644
index 0000000..9adef3b
--- /dev/null
+++ b/arch/powerpc/kernel/smp-tbsync.c
@@ -0,0 +1,171 @@
+/*
+ * Smp timebase synchronization for ppc.
+ *
+ * Copyright (C) 2003 Samuel Rydh (samuel@ibrium.se)
+ *
+ */
+
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/smp.h>
+#include <linux/unistd.h>
+#include <linux/init.h>
+#include <asm/atomic.h>
+#include <asm/smp.h>
+#include <asm/time.h>
+
+#define NUM_ITER 300
+
+enum {
+ kExit=0, kSetAndTest, kTest
+};
+
+static struct {
+ volatile u64 tb;
+ volatile u64 mark;
+ volatile int cmd;
+ volatile int handshake;
+ int filler[2];
+
+ volatile int ack;
+ int filler2[7];
+
+ volatile int race_result;
+} *tbsync;
+
+static volatile int running;
+
+static void __devinit enter_contest(u64 mark, long add)
+{
+ while (get_tb() < mark)
+ tbsync->race_result = add;
+}
+
+void __devinit smp_generic_take_timebase(void)
+{
+ int cmd;
+ u64 tb;
+
+ local_irq_disable();
+ while (!running)
+ barrier();
+ rmb();
+
+ for (;;) {
+ tbsync->ack = 1;
+ while (!tbsync->handshake)
+ barrier();
+ rmb();
+
+ cmd = tbsync->cmd;
+ tb = tbsync->tb;
+ mb();
+ tbsync->ack = 0;
+ if (cmd == kExit)
+ break;
+
+ 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, int num)
+{
+ int i, score=0;
+ u64 tb;
+ long mark;
+
+ tbsync->cmd = cmd;
+
+ local_irq_disable();
+ 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)
+ barrier();
+
+ while (get_tb() <= tb)
+ barrier();
+ tbsync->handshake = 0;
+ enter_contest(mark, 1);
+
+ while (!tbsync->ack)
+ barrier();
+
+ if (i++ > 0)
+ score += tbsync->race_result;
+ }
+ local_irq_enable();
+ return score;
+}
+
+void __devinit smp_generic_give_timebase(void)
+{
+ int i, score, score2, old, min=0, max=5000, offset=1000;
+
+ printk("Synchronizing timebase\n");
+
+ /* if this fails then this kernel won't work anyway... */
+ tbsync = kmalloc( sizeof(*tbsync), GFP_KERNEL );
+ memset( tbsync, 0, sizeof(*tbsync) );
+ mb();
+ running = 1;
+
+ 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);
+
+ printk("score %d, offset %d\n", score, offset );
+
+ if( score > 0 )
+ max = offset;
+ else
+ min = offset;
+ old = offset;
+ }
+ 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);
+ offset = (score < score2) ? min : max;
+
+ /* guard against inaccurate mttb */
+ for (i = 0; i < 10; i++) {
+ start_contest(kSetAndTest, offset, NUM_ITER/10);
+
+ if ((score2 = start_contest(kTest, offset, NUM_ITER)) < 0)
+ score2 = -score2;
+ if (score2 <= score || score2 < 20)
+ break;
+ }
+ printk("Final offset: %d (%d/%d)\n", offset, score2, NUM_ITER );
+
+ /* exiting */
+ tbsync->cmd = kExit;
+ wmb();
+ tbsync->handshake = 1;
+ while (tbsync->ack)
+ barrier();
+ tbsync->handshake = 0;
+ kfree(tbsync);
+ tbsync = NULL;
+ running = 0;
+}
diff --git a/arch/ppc64/Kconfig b/arch/ppc64/Kconfig
index 42677cc..b987164 100644
--- a/arch/ppc64/Kconfig
+++ b/arch/ppc64/Kconfig
@@ -89,12 +89,14 @@
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 @@
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 430cb39..f597c29 100644
--- a/arch/ppc64/kernel/Makefile
+++ b/arch/ppc64/kernel/Makefile
@@ -51,11 +51,6 @@
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/
diff --git a/arch/ppc64/kernel/smp-tbsync.c b/arch/ppc64/kernel/smp-tbsync.c
deleted file mode 100644
index 7d8ec99..0000000
--- a/arch/ppc64/kernel/smp-tbsync.c
+++ /dev/null
@@ -1,179 +0,0 @@
-/*
- * Smp timebase synchronization for ppc.
- *
- * Copyright (C) 2003 Samuel Rydh (samuel@ibrium.se)
- *
- */
-
-#include <linux/config.h>
-#include <linux/kernel.h>
-#include <linux/sched.h>
-#include <linux/smp.h>
-#include <linux/unistd.h>
-#include <linux/init.h>
-#include <asm/atomic.h>
-#include <asm/smp.h>
-#include <asm/time.h>
-
-#define NUM_ITER 300
-
-enum {
- kExit=0, kSetAndTest, kTest
-};
-
-static struct {
- volatile long tb;
- volatile long mark;
- volatile int cmd;
- volatile int handshake;
- int filler[3];
-
- volatile int ack;
- int filler2[7];
-
- volatile int race_result;
-} *tbsync;
-
-static volatile int running;
-
-static void __devinit
-enter_contest( long mark, long add )
-{
- while( (long)(mftb() - mark) < 0 )
- tbsync->race_result = add;
-}
-
-void __devinit
-smp_generic_take_timebase( void )
-{
- int cmd;
- long tb;
-
- local_irq_disable();
- while( !running )
- ;
- rmb();
-
- for( ;; ) {
- tbsync->ack = 1;
- while( !tbsync->handshake )
- ;
- rmb();
-
- cmd = tbsync->cmd;
- tb = tbsync->tb;
- tbsync->ack = 0;
- if( cmd == kExit )
- return;
-
- 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 );
- }
- local_irq_enable();
-}
-
-static int __devinit
-start_contest( int cmd, long offset, long num )
-{
- int i, score=0;
- long tb, mark;
-
- tbsync->cmd = cmd;
-
- local_irq_disable();
- for( i=-3; i<num; ) {
- tb = (long)mftb() + 400;
- tbsync->tb = tb + offset;
- tbsync->mark = mark = tb + 400;
-
- wmb();
-
- tbsync->handshake = 1;
- while( tbsync->ack )
- ;
-
- while( (long)(mftb() - tb) <= 0 )
- ;
- tbsync->handshake = 0;
- enter_contest( mark, 1 );
-
- while( !tbsync->ack )
- ;
-
- if ((tbsync->tb ^ (long)mftb()) & 0x8000000000000000ul)
- continue;
- if( i++ > 0 )
- score += tbsync->race_result;
- }
- local_irq_enable();
- return score;
-}
-
-void __devinit
-smp_generic_give_timebase( void )
-{
- int i, score, score2, old, min=0, max=5000, offset=1000;
-
- printk("Synchronizing timebase\n");
-
- /* if this fails then this kernel won't work anyway... */
- tbsync = kmalloc( sizeof(*tbsync), GFP_KERNEL );
- memset( tbsync, 0, sizeof(*tbsync) );
- mb();
- running = 1;
-
- while( !tbsync->ack )
- ;
-
- printk("Got ack\n");
-
- /* binary search */
- for( old=-1 ; old != offset ; offset=(min+max)/2 ) {
- score = start_contest( kSetAndTest, offset, NUM_ITER );
-
- printk("score %d, offset %d\n", score, offset );
-
- if( score > 0 )
- max = offset;
- else
- min = offset;
- old = offset;
- }
- 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 );
- offset = (score < score2) ? min : max;
-
- /* guard against inaccurate mttb */
- for( i=0; i<10; i++ ) {
- start_contest( kSetAndTest, offset, NUM_ITER/10 );
-
- if( (score2=start_contest(kTest, offset, NUM_ITER)) < 0 )
- score2 = -score2;
- if( score2 <= score || score2 < 20 )
- break;
- }
- printk("Final offset: %d (%d/%d)\n", offset, score2, NUM_ITER );
-
- /* exiting */
- tbsync->cmd = kExit;
- wmb();
- tbsync->handshake = 1;
- while( tbsync->ack )
- ;
- tbsync->handshake = 0;
- kfree( tbsync );
- tbsync = NULL;
- running = 0;
-}