Merge with master.kernel.org:/home/rmk/linux-2.6-rmk.git

[safe/jmp/linux-2.6] / arch / ppc / platforms / pmac_smp.c

diff --git a/arch/ppc/platforms/pmac_smp.c b/arch/ppc/platforms/pmac_smp.c
index 2b88745..731841f 100644 (file)
--- a/arch/ppc/platforms/pmac_smp.c
+++ b/arch/ppc/platforms/pmac_smp.c
@@ -116,6 +116,8 @@ static unsigned int core99_tb_gpio;
 
 /* Sync flag for HW tb sync */
 static volatile int sec_tb_reset = 0;
+static unsigned int pri_tb_hi, pri_tb_lo;
+static unsigned int pri_tb_stamp;
 
 static void __init core99_init_caches(int cpu)
 {
@@ -453,7 +455,7 @@ static int __init smp_core99_probe(void)
 #endif
        struct device_node *cpus, *firstcpu;
        int i, ncpus = 0, boot_cpu = -1;
-       u32 *tbprop;
+       u32 *tbprop = NULL;
 
        if (ppc_md.progress) ppc_md.progress("smp_core99_probe", 0x345);
        cpus = firstcpu = find_type_devices("cpu");
@@ -576,46 +578,74 @@ static void __init smp_core99_setup_cpu(int cpu_nr)
        }
 }
 
-void __init smp_core99_take_timebase(void)
+/* not __init, called in sleep/wakeup code */
+void smp_core99_take_timebase(void)
 {
-       /* Secondary processor "takes" the timebase by freezing
-        * it, resetting its local TB and telling CPU 0 to go on
-        */
-       pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, core99_tb_gpio, 4);
-       pmac_call_feature(PMAC_FTR_READ_GPIO, NULL, core99_tb_gpio, 0);
+       unsigned long flags;
+
+       /* tell the primary we're here */
+       sec_tb_reset = 1;
        mb();
 
-       set_dec(tb_ticks_per_jiffy);
-       set_tb(0, 0);
-       last_jiffy_stamp(smp_processor_id()) = 0;
+       /* wait for the primary to set pri_tb_hi/lo */
+       while (sec_tb_reset < 2)
+               mb();
 
+       /* set our stuff the same as the primary */
+       local_irq_save(flags);
+       set_dec(1);
+       set_tb(pri_tb_hi, pri_tb_lo);
+       last_jiffy_stamp(smp_processor_id()) = pri_tb_stamp;
+       mb();
+
+       /* tell the primary we're done */
+               sec_tb_reset = 0;
        mb();
-               sec_tb_reset = 1;
+       local_irq_restore(flags);
 }
 
-void __init smp_core99_give_timebase(void)
+/* not __init, called in sleep/wakeup code */
+void smp_core99_give_timebase(void)
 {
+       unsigned long flags;
        unsigned int t;
 
-       /* Primary processor waits for secondary to have frozen
-        * the timebase, resets local TB, and kick timebase again
-        */
-       /* wait for the secondary to have reset its TB before proceeding */
-       for (t = 1000; t > 0 && !sec_tb_reset; --t)
-               udelay(1000);
-       if (t == 0)
+       /* wait for the secondary to be in take_timebase */
+       for (t = 100000; t > 0 && !sec_tb_reset; --t)
+               udelay(10);
+       if (!sec_tb_reset) {
                printk(KERN_WARNING "Timeout waiting sync on second CPU\n");
+               return;
+       }
 
-               set_dec(tb_ticks_per_jiffy);
-       set_tb(0, 0);
-       last_jiffy_stamp(smp_processor_id()) = 0;
+       /* freeze the timebase and read it */
+       /* disable interrupts so the timebase is disabled for the
+          shortest possible time */
+       local_irq_save(flags);
+       pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, core99_tb_gpio, 4);
+       pmac_call_feature(PMAC_FTR_READ_GPIO, NULL, core99_tb_gpio, 0);
+       mb();
+       pri_tb_hi = get_tbu();
+       pri_tb_lo = get_tbl();
+       pri_tb_stamp = last_jiffy_stamp(smp_processor_id());
        mb();
 
+       /* tell the secondary we're ready */
+       sec_tb_reset = 2;
+       mb();
+
+       /* wait for the secondary to have taken it */
+       for (t = 100000; t > 0 && sec_tb_reset; --t)
+               udelay(10);
+       if (sec_tb_reset)
+               printk(KERN_WARNING "Timeout waiting sync(2) on second CPU\n");
+       else
+               smp_tb_synchronized = 1;
+
        /* Now, restart the timebase by leaving the GPIO to an open collector */
                pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, core99_tb_gpio, 0);
         pmac_call_feature(PMAC_FTR_READ_GPIO, NULL, core99_tb_gpio, 0);
-
-       smp_tb_synchronized = 1;
+       local_irq_restore(flags);
 }