Several platforms use their own copy of what is essentially the same code, using RTAS to synchronize the timebases when bringing up new CPUs. This moves it all into a single common implementation and additionally turns the spinlock into a raw spinlock since the former can rely on the timebase not being frozen when spinlock debugging is enabled, and finally masks interrupts while the timebase is disabled.
Signed-off-by: Benjamin Herrenschmidt <[email protected]> --- arch/powerpc/include/asm/rtas.h | 3 +++ arch/powerpc/kernel/rtas.c | 31 +++++++++++++++++++++++++++++++ arch/powerpc/platforms/cell/smp.c | 30 ++---------------------------- arch/powerpc/platforms/chrp/smp.c | 30 ++---------------------------- arch/powerpc/platforms/pseries/smp.c | 30 ++---------------------------- 5 files changed, 40 insertions(+), 84 deletions(-) --- linux-work.orig/arch/powerpc/platforms/cell/smp.c 2009-06-17 11:56:31.000000000 +1000 +++ linux-work/arch/powerpc/platforms/cell/smp.c 2009-06-17 11:56:42.000000000 +1000 @@ -36,7 +36,6 @@ #include <asm/prom.h> #include <asm/smp.h> #include <asm/paca.h> -#include <asm/time.h> #include <asm/machdep.h> #include <asm/cputable.h> #include <asm/firmware.h> @@ -140,31 +139,6 @@ static void __devinit smp_cell_setup_cpu mtspr(SPRN_DABRX, DABRX_KERNEL | DABRX_USER); } -static DEFINE_SPINLOCK(timebase_lock); -static unsigned long timebase = 0; - -static void __devinit cell_give_timebase(void) -{ - spin_lock(&timebase_lock); - rtas_call(rtas_token("freeze-time-base"), 0, 1, NULL); - timebase = get_tb(); - spin_unlock(&timebase_lock); - - while (timebase) - barrier(); - rtas_call(rtas_token("thaw-time-base"), 0, 1, NULL); -} - -static void __devinit cell_take_timebase(void) -{ - while (!timebase) - barrier(); - spin_lock(&timebase_lock); - set_tb(timebase >> 32, timebase & 0xffffffff); - timebase = 0; - spin_unlock(&timebase_lock); -} - static void __devinit smp_cell_kick_cpu(int nr) { BUG_ON(nr < 0 || nr >= NR_CPUS); @@ -224,8 +198,8 @@ void __init smp_init_cell(void) /* Non-lpar has additional take/give timebase */ if (rtas_token("freeze-time-base") != RTAS_UNKNOWN_SERVICE) { - smp_ops->give_timebase = cell_give_timebase; - smp_ops->take_timebase = cell_take_timebase; + smp_ops->give_timebase = rtas_give_timebase; + smp_ops->take_timebase = rtas_take_timebase; } DBG(" <- smp_init_cell()\n"); Index: linux-work/arch/powerpc/platforms/chrp/smp.c =================================================================== --- linux-work.orig/arch/powerpc/platforms/chrp/smp.c 2009-06-17 11:56:31.000000000 +1000 +++ linux-work/arch/powerpc/platforms/chrp/smp.c 2009-06-17 11:56:42.000000000 +1000 @@ -26,7 +26,6 @@ #include <asm/io.h> #include <asm/prom.h> #include <asm/smp.h> -#include <asm/time.h> #include <asm/machdep.h> #include <asm/mpic.h> #include <asm/rtas.h> @@ -45,37 +44,12 @@ static void __devinit smp_chrp_setup_cpu static DEFINE_SPINLOCK(timebase_lock); static unsigned int timebase_upper = 0, timebase_lower = 0; -void __devinit smp_chrp_give_timebase(void) -{ - spin_lock(&timebase_lock); - rtas_call(rtas_token("freeze-time-base"), 0, 1, NULL); - timebase_upper = get_tbu(); - timebase_lower = get_tbl(); - spin_unlock(&timebase_lock); - - while (timebase_upper || timebase_lower) - barrier(); - rtas_call(rtas_token("thaw-time-base"), 0, 1, NULL); -} - -void __devinit smp_chrp_take_timebase(void) -{ - while (!(timebase_upper || timebase_lower)) - barrier(); - spin_lock(&timebase_lock); - set_tb(timebase_upper, timebase_lower); - timebase_upper = 0; - timebase_lower = 0; - spin_unlock(&timebase_lock); - printk("CPU %i taken timebase\n", smp_processor_id()); -} - /* CHRP with openpic */ struct smp_ops_t chrp_smp_ops = { .message_pass = smp_mpic_message_pass, .probe = smp_mpic_probe, .kick_cpu = smp_chrp_kick_cpu, .setup_cpu = smp_chrp_setup_cpu, - .give_timebase = smp_chrp_give_timebase, - .take_timebase = smp_chrp_take_timebase, + .give_timebase = rtas_give_timebase, + .take_timebase = rtas_take_timebase, }; Index: linux-work/arch/powerpc/platforms/pseries/smp.c =================================================================== --- linux-work.orig/arch/powerpc/platforms/pseries/smp.c 2009-06-17 11:56:31.000000000 +1000 +++ linux-work/arch/powerpc/platforms/pseries/smp.c 2009-06-17 11:56:42.000000000 +1000 @@ -35,7 +35,6 @@ #include <asm/prom.h> #include <asm/smp.h> #include <asm/paca.h> -#include <asm/time.h> #include <asm/machdep.h> #include <asm/cputable.h> #include <asm/firmware.h> @@ -118,31 +117,6 @@ static void __devinit smp_xics_setup_cpu } #endif /* CONFIG_XICS */ -static DEFINE_SPINLOCK(timebase_lock); -static unsigned long timebase = 0; - -static void __devinit pSeries_give_timebase(void) -{ - spin_lock(&timebase_lock); - rtas_call(rtas_token("freeze-time-base"), 0, 1, NULL); - timebase = get_tb(); - spin_unlock(&timebase_lock); - - while (timebase) - barrier(); - rtas_call(rtas_token("thaw-time-base"), 0, 1, NULL); -} - -static void __devinit pSeries_take_timebase(void) -{ - while (!timebase) - barrier(); - spin_lock(&timebase_lock); - set_tb(timebase >> 32, timebase & 0xffffffff); - timebase = 0; - spin_unlock(&timebase_lock); -} - static void __devinit smp_pSeries_kick_cpu(int nr) { BUG_ON(nr < 0 || nr >= NR_CPUS); @@ -209,8 +183,8 @@ static void __init smp_init_pseries(void /* Non-lpar has additional take/give timebase */ if (rtas_token("freeze-time-base") != RTAS_UNKNOWN_SERVICE) { - smp_ops->give_timebase = pSeries_give_timebase; - smp_ops->take_timebase = pSeries_take_timebase; + smp_ops->give_timebase = rtas_give_timebase; + smp_ops->take_timebase = rtas_take_timebase; } pr_debug(" <- smp_init_pSeries()\n"); Index: linux-work/arch/powerpc/include/asm/rtas.h =================================================================== --- linux-work.orig/arch/powerpc/include/asm/rtas.h 2009-06-17 11:56:31.000000000 +1000 +++ linux-work/arch/powerpc/include/asm/rtas.h 2009-06-17 11:56:42.000000000 +1000 @@ -245,5 +245,8 @@ static inline u32 rtas_config_addr(int b (devfn << 8) | (reg & 0xff); } +extern void __cpuinit rtas_give_timebase(void); +extern void __cpuinit rtas_take_timebase(void); + #endif /* __KERNEL__ */ #endif /* _POWERPC_RTAS_H */ Index: linux-work/arch/powerpc/kernel/rtas.c =================================================================== --- linux-work.orig/arch/powerpc/kernel/rtas.c 2009-06-17 11:56:31.000000000 +1000 +++ linux-work/arch/powerpc/kernel/rtas.c 2009-06-17 11:59:58.000000000 +1000 @@ -38,6 +38,7 @@ #include <asm/syscalls.h> #include <asm/smp.h> #include <asm/atomic.h> +#include <asm/time.h> struct rtas_t rtas = { .lock = __RAW_SPIN_LOCK_UNLOCKED @@ -971,3 +972,33 @@ int __init early_init_dt_scan_rtas(unsig /* break now */ return 1; } + +static raw_spinlock_t timebase_lock; +static u64 timebase = 0; + +void __cpuinit rtas_give_timebase(void) +{ + unsigned long flags; + + local_irq_save(flags); + hard_irq_disable(); + __raw_spin_lock(&timebase_lock); + rtas_call(rtas_token("freeze-time-base"), 0, 1, NULL); + timebase = get_tb(); + __raw_spin_unlock(&timebase_lock); + + while (timebase) + barrier(); + rtas_call(rtas_token("thaw-time-base"), 0, 1, NULL); + local_irq_restore(flags); +} + +void __cpuinit rtas_take_timebase(void) +{ + while (!timebase) + barrier(); + __raw_spin_lock(&timebase_lock); + set_tb(timebase >> 32, timebase & 0xffffffff); + timebase = 0; + __raw_spin_unlock(&timebase_lock); +} _______________________________________________ Linuxppc-dev mailing list [email protected] https://lists.ozlabs.org/listinfo/linuxppc-dev
