powerpc: Merge smp-tbsync.c (the generic timebase sync routine)

Signed-off-by: Paul Mackerras <paulus@samba.org>

5 files changed, 65 insertions, 65 deletions

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
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 == 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 );
+                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, 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/