diff options
Diffstat (limited to 'arch/ppc')
| -rw-r--r-- | arch/ppc/platforms/pmac_smp.c | 78 |
1 files changed, 54 insertions, 24 deletions
diff --git a/arch/ppc/platforms/pmac_smp.c b/arch/ppc/platforms/pmac_smp.c index 2b88745576a0..731841f9a5b8 100644 --- 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); } |