[MIPS] time: SMP-proofing of Sibyte clockevent/clocksource code.
The BCM148 has 4 cores but there are also just 4 generic timers available
so use the ZBbus cycle counter instead of it. In addition the ZBbus
counter also offers a much higher resolution and 64-bit counting so I'm
considering a later complete conversion to it once I figure out if all
members of the Sibyte SOC family support it - the docs seem to agree but
the headers files seem to disagree ...
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/sibyte/bcm1480/irq.c b/arch/mips/sibyte/bcm1480/irq.c
index 7aa79bf..10299ba 100644
--- a/arch/mips/sibyte/bcm1480/irq.c
+++ b/arch/mips/sibyte/bcm1480/irq.c
@@ -452,6 +452,43 @@
extern void bcm1480_mailbox_interrupt(void);
+static inline void dispatch_ip4(void)
+{
+ int cpu = smp_processor_id();
+ int irq = K_BCM1480_INT_TIMER_0 + cpu;
+
+ /* Reset the timer */
+ __raw_writeq(M_SCD_TIMER_ENABLE|M_SCD_TIMER_MODE_CONTINUOUS,
+ IOADDR(A_SCD_TIMER_REGISTER(cpu, R_SCD_TIMER_CFG)));
+
+ do_IRQ(irq);
+}
+
+static inline void dispatch_ip2(void)
+{
+ unsigned long long mask_h, mask_l;
+ unsigned int cpu = smp_processor_id();
+ unsigned long base;
+
+ /*
+ * Default...we've hit an IP[2] interrupt, which means we've got to
+ * check the 1480 interrupt registers to figure out what to do. Need
+ * to detect which CPU we're on, now that smp_affinity is supported.
+ */
+ base = A_BCM1480_IMR_MAPPER(cpu);
+ mask_h = __raw_readq(
+ IOADDR(base + R_BCM1480_IMR_INTERRUPT_STATUS_BASE_H));
+ mask_l = __raw_readq(
+ IOADDR(base + R_BCM1480_IMR_INTERRUPT_STATUS_BASE_L));
+
+ if (mask_h) {
+ if (mask_h ^ 1)
+ do_IRQ(fls64(mask_h) - 1);
+ else if (mask_l)
+ do_IRQ(63 + fls64(mask_l));
+ }
+}
+
asmlinkage void plat_irq_dispatch(void)
{
unsigned int pending;
@@ -469,17 +506,8 @@
else
#endif
- if (pending & CAUSEF_IP4) {
- int cpu = smp_processor_id();
- int irq = K_BCM1480_INT_TIMER_0 + cpu;
-
- /* Reset the timer */
- __raw_writeq(M_SCD_TIMER_ENABLE|M_SCD_TIMER_MODE_CONTINUOUS,
- IOADDR(A_SCD_TIMER_REGISTER(cpu, R_SCD_TIMER_CFG)));
-
- do_IRQ(irq);
- }
-
+ if (pending & CAUSEF_IP4)
+ dispatch_ip4();
#ifdef CONFIG_SMP
else if (pending & CAUSEF_IP3)
bcm1480_mailbox_interrupt();
@@ -490,27 +518,6 @@
bcm1480_kgdb_interrupt(); /* KGDB (uart 1) */
#endif
- else if (pending & CAUSEF_IP2) {
- unsigned long long mask_h, mask_l;
- unsigned long base;
-
- /*
- * Default...we've hit an IP[2] interrupt, which means we've
- * got to check the 1480 interrupt registers to figure out what
- * to do. Need to detect which CPU we're on, now that
- * smp_affinity is supported.
- */
- base = A_BCM1480_IMR_MAPPER(smp_processor_id());
- mask_h = __raw_readq(
- IOADDR(base + R_BCM1480_IMR_INTERRUPT_STATUS_BASE_H));
- mask_l = __raw_readq(
- IOADDR(base + R_BCM1480_IMR_INTERRUPT_STATUS_BASE_L));
-
- if (mask_h) {
- if (mask_h ^ 1)
- do_IRQ(fls64(mask_h) - 1);
- else
- do_IRQ(63 + fls64(mask_l));
- }
- }
+ else if (pending & CAUSEF_IP2)
+ dispatch_ip2();
}
diff --git a/arch/mips/sibyte/bcm1480/smp.c b/arch/mips/sibyte/bcm1480/smp.c
index 02b266a..436ba78 100644
--- a/arch/mips/sibyte/bcm1480/smp.c
+++ b/arch/mips/sibyte/bcm1480/smp.c
@@ -58,7 +58,7 @@
/*
* SMP init and finish on secondary CPUs
*/
-void bcm1480_smp_init(void)
+void __cpuinit bcm1480_smp_init(void)
{
unsigned int imask = STATUSF_IP4 | STATUSF_IP3 | STATUSF_IP2 |
STATUSF_IP1 | STATUSF_IP0;
@@ -67,7 +67,7 @@
change_c0_status(ST0_IM, imask);
}
-void bcm1480_smp_finish(void)
+void __cpuinit bcm1480_smp_finish(void)
{
extern void sb1480_clockevent_init(void);
diff --git a/arch/mips/sibyte/bcm1480/time.c b/arch/mips/sibyte/bcm1480/time.c
index c730744..610f025 100644
--- a/arch/mips/sibyte/bcm1480/time.c
+++ b/arch/mips/sibyte/bcm1480/time.c
@@ -15,22 +15,12 @@
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
-
-/*
- * These are routines to set up and handle interrupts from the
- * bcm1480 general purpose timer 0. We're using the timer as a
- * system clock, so we set it up to run at 100 Hz. On every
- * interrupt, we update our idea of what the time of day is,
- * then call do_timer() in the architecture-independent kernel
- * code to do general bookkeeping (e.g. update jiffies, run
- * bottom halves, etc.)
- */
#include <linux/clockchips.h>
#include <linux/interrupt.h>
+#include <linux/irq.h>
#include <linux/percpu.h>
#include <linux/spinlock.h>
-#include <asm/irq.h>
#include <asm/addrspace.h>
#include <asm/time.h>
#include <asm/io.h>
@@ -47,33 +37,10 @@
#define IMR_IP3_VAL K_BCM1480_INT_MAP_I1
#define IMR_IP4_VAL K_BCM1480_INT_MAP_I2
-#ifdef CONFIG_SIMULATION
-#define BCM1480_HPT_VALUE 50000
-#else
-#define BCM1480_HPT_VALUE 1000000
-#endif
-
extern int bcm1480_steal_irq(int irq);
-void __init plat_time_init(void)
-{
- unsigned int cpu = smp_processor_id();
- unsigned int irq = K_BCM1480_INT_TIMER_0 + cpu;
-
- BUG_ON(cpu > 3); /* Only have 4 general purpose timers */
-
- bcm1480_mask_irq(cpu, irq);
-
- /* Map the timer interrupt to ip[4] of this cpu */
- __raw_writeq(IMR_IP4_VAL, IOADDR(A_BCM1480_IMR_REGISTER(cpu, R_BCM1480_IMR_INTERRUPT_MAP_BASE_H)
- + (irq<<3)));
-
- bcm1480_unmask_irq(cpu, irq);
- bcm1480_steal_irq(irq);
-}
-
/*
- * The general purpose timer ticks at 1 Mhz independent if
+ * The general purpose timer ticks at 1MHz independent if
* the rest of the system
*/
static void sibyte_set_mode(enum clock_event_mode mode,
@@ -88,7 +55,7 @@
switch (mode) {
case CLOCK_EVT_MODE_PERIODIC:
__raw_writeq(0, timer_cfg);
- __raw_writeq(BCM1480_HPT_VALUE / HZ - 1, timer_init);
+ __raw_writeq((V_SCD_TIMER_FREQ / HZ) - 1, timer_init);
__raw_writeq(M_SCD_TIMER_ENABLE | M_SCD_TIMER_MODE_CONTINUOUS,
timer_cfg);
break;
@@ -121,80 +88,96 @@
return res;
}
-static DEFINE_PER_CPU(struct clock_event_device, sibyte_hpt_clockevent);
-
static irqreturn_t sibyte_counter_handler(int irq, void *dev_id)
{
unsigned int cpu = smp_processor_id();
- struct clock_event_device *cd = &per_cpu(sibyte_hpt_clockevent, cpu);
+ struct clock_event_device *cd = dev_id;
+ void __iomem *timer_cfg;
+
+ timer_cfg = IOADDR(A_SCD_TIMER_REGISTER(cpu, R_SCD_TIMER_CFG));
/* Reset the timer */
__raw_writeq(M_SCD_TIMER_ENABLE | M_SCD_TIMER_MODE_CONTINUOUS,
- IOADDR(A_SCD_TIMER_REGISTER(cpu, R_SCD_TIMER_CFG)));
+ timer_cfg);
cd->event_handler(cd);
return IRQ_HANDLED;
}
-static struct irqaction sibyte_counter_irqaction = {
- .handler = sibyte_counter_handler,
- .flags = IRQF_DISABLED | IRQF_PERCPU,
- .name = "timer",
-};
+static DEFINE_PER_CPU(struct clock_event_device, sibyte_hpt_clockevent);
+static DEFINE_PER_CPU(struct irqaction, sibyte_hpt_irqaction);
+static DEFINE_PER_CPU(char [18], sibyte_hpt_name);
-/*
- * This interrupt is "special" in that it doesn't use the request_irq
- * way to hook the irq line. The timer interrupt is initialized early
- * enough to make this a major pain, and it's also firing enough to
- * warrant a bit of special case code. bcm1480_timer_interrupt is
- * called directly from irq_handler.S when IP[4] is set during an
- * interrupt
- */
void __cpuinit sb1480_clockevent_init(void)
{
unsigned int cpu = smp_processor_id();
unsigned int irq = K_BCM1480_INT_TIMER_0 + cpu;
+ struct irqaction *action = &per_cpu(sibyte_hpt_irqaction, cpu);
struct clock_event_device *cd = &per_cpu(sibyte_hpt_clockevent, cpu);
+ unsigned char *name = per_cpu(sibyte_hpt_name, cpu);
- cd->name = "bcm1480-counter";
+ BUG_ON(cpu > 3); /* Only have 4 general purpose timers */
+
+ sprintf(name, "bcm1480-counter %d", cpu);
+ cd->name = name;
cd->features = CLOCK_EVT_FEAT_PERIODIC |
CLOCK_EVT_MODE_ONESHOT;
+ clockevent_set_clock(cd, V_SCD_TIMER_FREQ);
+ cd->max_delta_ns = clockevent_delta2ns(0x7fffff, cd);
+ cd->min_delta_ns = clockevent_delta2ns(1, cd);
+ cd->rating = 200;
+ cd->irq = irq;
+ cd->cpumask = cpumask_of_cpu(cpu);
cd->set_next_event = sibyte_next_event;
cd->set_mode = sibyte_set_mode;
- cd->irq = irq;
- clockevent_set_clock(cd, BCM1480_HPT_VALUE);
+ clockevents_register_device(cd);
- setup_irq(irq, &sibyte_counter_irqaction);
+ bcm1480_mask_irq(cpu, irq);
+
+ /*
+ * Map timer interrupt to IP[4] of this cpu
+ */
+ __raw_writeq(IMR_IP4_VAL,
+ IOADDR(A_BCM1480_IMR_REGISTER(cpu,
+ R_BCM1480_IMR_INTERRUPT_MAP_BASE_H) + (irq << 3)));
+
+ bcm1480_unmask_irq(cpu, irq);
+ bcm1480_steal_irq(irq);
+
+ action->handler = sibyte_counter_handler;
+ action->flags = IRQF_DISABLED | IRQF_PERCPU;
+ action->name = name;
+ action->dev_id = cd;
+ setup_irq(irq, action);
}
static cycle_t bcm1480_hpt_read(void)
{
- /* We assume this function is called xtime_lock held. */
- unsigned long count =
- __raw_readq(IOADDR(A_SCD_TIMER_REGISTER(0, R_SCD_TIMER_CNT)));
- return (jiffies + 1) * (BCM1480_HPT_VALUE / HZ) - count;
+ return (cycle_t) __raw_readq(IOADDR(A_SCD_ZBBUS_CYCLE_COUNT));
}
struct clocksource bcm1480_clocksource = {
- .name = "MIPS",
+ .name = "zbbus-cycles",
.rating = 200,
.read = bcm1480_hpt_read,
- .mask = CLOCKSOURCE_MASK(32),
- .shift = 32,
+ .mask = CLOCKSOURCE_MASK(64),
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};
void __init sb1480_clocksource_init(void)
{
struct clocksource *cs = &bcm1480_clocksource;
+ unsigned int plldiv;
+ unsigned long zbbus;
- clocksource_set_clock(cs, BCM1480_HPT_VALUE);
+ plldiv = G_BCM1480_SYS_PLL_DIV(__raw_readq(IOADDR(A_SCD_SYSTEM_CFG)));
+ zbbus = ((plldiv >> 1) * 50000000) + ((plldiv & 1) * 25000000);
+ clocksource_set_clock(cs, zbbus);
clocksource_register(cs);
}
-void __init bcm1480_hpt_setup(void)
+void __init plat_time_init(void)
{
- mips_hpt_frequency = BCM1480_HPT_VALUE;
sb1480_clocksource_init();
sb1480_clockevent_init();
}
diff --git a/arch/mips/sibyte/sb1250/irq.c b/arch/mips/sibyte/sb1250/irq.c
index 500d17e..53780a1 100644
--- a/arch/mips/sibyte/sb1250/irq.c
+++ b/arch/mips/sibyte/sb1250/irq.c
@@ -402,6 +402,22 @@
extern void sb1250_mailbox_interrupt(void);
+static inline void dispatch_ip2(void)
+{
+ unsigned int cpu = smp_processor_id();
+ unsigned long long mask;
+
+ /*
+ * Default...we've hit an IP[2] interrupt, which means we've got to
+ * check the 1250 interrupt registers to figure out what to do. Need
+ * to detect which CPU we're on, now that smp_affinity is supported.
+ */
+ mask = __raw_readq(IOADDR(A_IMR_REGISTER(cpu,
+ R_IMR_INTERRUPT_STATUS_BASE)));
+ if (mask)
+ do_IRQ(fls64(mask) - 1);
+}
+
asmlinkage void plat_irq_dispatch(void)
{
unsigned int cpu = smp_processor_id();
@@ -434,21 +450,8 @@
sb1250_kgdb_interrupt();
#endif
- else if (pending & CAUSEF_IP2) {
- unsigned long long mask;
-
- /*
- * Default...we've hit an IP[2] interrupt, which means we've
- * got to check the 1250 interrupt registers to figure out what
- * to do. Need to detect which CPU we're on, now that
- * smp_affinity is supported.
- */
- mask = __raw_readq(IOADDR(A_IMR_REGISTER(smp_processor_id(),
- R_IMR_INTERRUPT_STATUS_BASE)));
- if (mask)
- do_IRQ(fls64(mask) - 1);
- else
- spurious_interrupt();
- } else
+ else if (pending & CAUSEF_IP2)
+ dispatch_ip2();
+ else
spurious_interrupt();
}
diff --git a/arch/mips/sibyte/sb1250/smp.c b/arch/mips/sibyte/sb1250/smp.c
index aaa4f30..3f52c95 100644
--- a/arch/mips/sibyte/sb1250/smp.c
+++ b/arch/mips/sibyte/sb1250/smp.c
@@ -46,7 +46,7 @@
/*
* SMP init and finish on secondary CPUs
*/
-void sb1250_smp_init(void)
+void __cpuinit sb1250_smp_init(void)
{
unsigned int imask = STATUSF_IP4 | STATUSF_IP3 | STATUSF_IP2 |
STATUSF_IP1 | STATUSF_IP0;
@@ -55,7 +55,7 @@
change_c0_status(ST0_IM, imask);
}
-void sb1250_smp_finish(void)
+void __cpuinit sb1250_smp_finish(void)
{
extern void sb1250_clockevent_init(void);
diff --git a/arch/mips/sibyte/sb1250/time.c b/arch/mips/sibyte/sb1250/time.c
index 9ef5462..a41e908 100644
--- a/arch/mips/sibyte/sb1250/time.c
+++ b/arch/mips/sibyte/sb1250/time.c
@@ -52,26 +52,6 @@
extern int sb1250_steal_irq(int irq);
-static cycle_t sb1250_hpt_read(void);
-
-void __init sb1250_hpt_setup(void)
-{
- int cpu = smp_processor_id();
-
- if (!cpu) {
- /* Setup hpt using timer #3 but do not enable irq for it */
- __raw_writeq(0, IOADDR(A_SCD_TIMER_REGISTER(SB1250_HPT_NUM, R_SCD_TIMER_CFG)));
- __raw_writeq(SB1250_HPT_VALUE,
- IOADDR(A_SCD_TIMER_REGISTER(SB1250_HPT_NUM, R_SCD_TIMER_INIT)));
- __raw_writeq(M_SCD_TIMER_ENABLE | M_SCD_TIMER_MODE_CONTINUOUS,
- IOADDR(A_SCD_TIMER_REGISTER(SB1250_HPT_NUM, R_SCD_TIMER_CFG)));
-
- mips_hpt_frequency = V_SCD_TIMER_FREQ;
- clocksource_mips.read = sb1250_hpt_read;
- clocksource_mips.mask = M_SCD_TIMER_INIT;
- }
-}
-
/*
* The general purpose timer ticks at 1 Mhz independent if
* the rest of the system
@@ -121,18 +101,14 @@
return 0;
}
-struct clock_event_device sibyte_hpt_clockevent = {
- .name = "sb1250-counter",
- .features = CLOCK_EVT_FEAT_PERIODIC,
- .set_mode = sibyte_set_mode,
- .set_next_event = sibyte_next_event,
- .shift = 32,
- .irq = 0,
-};
-
static irqreturn_t sibyte_counter_handler(int irq, void *dev_id)
{
- struct clock_event_device *cd = &sibyte_hpt_clockevent;
+ unsigned int cpu = smp_processor_id();
+ struct clock_event_device *cd = dev_id;
+
+ /* ACK interrupt */
+ ____raw_writeq(M_SCD_TIMER_ENABLE | M_SCD_TIMER_MODE_CONTINUOUS,
+ IOADDR(A_SCD_TIMER_REGISTER(cpu, R_SCD_TIMER_CFG)));
cd->event_handler(cd);
@@ -145,15 +121,35 @@
.name = "timer",
};
+static DEFINE_PER_CPU(struct clock_event_device, sibyte_hpt_clockevent);
+static DEFINE_PER_CPU(struct irqaction, sibyte_hpt_irqaction);
+static DEFINE_PER_CPU(char [18], sibyte_hpt_name);
+
void __cpuinit sb1250_clockevent_init(void)
{
- struct clock_event_device *cd = &sibyte_hpt_clockevent;
unsigned int cpu = smp_processor_id();
- int irq = K_INT_TIMER_0 + cpu;
+ unsigned int irq = K_INT_TIMER_0 + cpu;
+ struct irqaction *action = &per_cpu(sibyte_hpt_irqaction, cpu);
+ struct clock_event_device *cd = &per_cpu(sibyte_hpt_clockevent, cpu);
+ unsigned char *name = per_cpu(sibyte_hpt_name, cpu);
/* Only have 4 general purpose timers, and we use last one as hpt */
BUG_ON(cpu > 2);
+ sprintf(name, "bcm1480-counter %d", cpu);
+ cd->name = name;
+ cd->features = CLOCK_EVT_FEAT_PERIODIC |
+ CLOCK_EVT_MODE_ONESHOT;
+ clockevent_set_clock(cd, V_SCD_TIMER_FREQ);
+ cd->max_delta_ns = clockevent_delta2ns(0x7fffff, cd);
+ cd->min_delta_ns = clockevent_delta2ns(1, cd);
+ cd->rating = 200;
+ cd->irq = irq;
+ cd->cpumask = cpumask_of_cpu(cpu);
+ cd->set_next_event = sibyte_next_event;
+ cd->set_mode = sibyte_set_mode;
+ clockevents_register_device(cd);
+
sb1250_mask_irq(cpu, irq);
/* Map the timer interrupt to ip[4] of this cpu */
@@ -165,17 +161,11 @@
sb1250_unmask_irq(cpu, irq);
sb1250_steal_irq(irq);
- /*
- * This interrupt is "special" in that it doesn't use the request_irq
- * way to hook the irq line. The timer interrupt is initialized early
- * enough to make this a major pain, and it's also firing enough to
- * warrant a bit of special case code. sb1250_timer_interrupt is
- * called directly from irq_handler.S when IP[4] is set during an
- * interrupt
- */
+ action->handler = sibyte_counter_handler;
+ action->flags = IRQF_DISABLED | IRQF_PERCPU;
+ action->name = name;
+ action->dev_id = cd;
setup_irq(irq, &sibyte_irqaction);
-
- clockevents_register_device(cd);
}
/*
@@ -195,8 +185,7 @@
.name = "MIPS",
.rating = 200,
.read = sb1250_hpt_read,
- .mask = CLOCKSOURCE_MASK(32),
- .shift = 32,
+ .mask = CLOCKSOURCE_MASK(23),
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};
@@ -204,6 +193,17 @@
{
struct clocksource *cs = &bcm1250_clocksource;
+ /* Setup hpt using timer #3 but do not enable irq for it */
+ __raw_writeq(0,
+ IOADDR(A_SCD_TIMER_REGISTER(SB1250_HPT_NUM,
+ R_SCD_TIMER_CFG)));
+ __raw_writeq(SB1250_HPT_VALUE,
+ IOADDR(A_SCD_TIMER_REGISTER(SB1250_HPT_NUM,
+ R_SCD_TIMER_INIT)));
+ __raw_writeq(M_SCD_TIMER_ENABLE | M_SCD_TIMER_MODE_CONTINUOUS,
+ IOADDR(A_SCD_TIMER_REGISTER(SB1250_HPT_NUM,
+ R_SCD_TIMER_CFG)));
+
clocksource_set_clock(cs, V_SCD_TIMER_FREQ);
clocksource_register(cs);
}
diff --git a/include/asm-mips/sibyte/sb1250.h b/include/asm-mips/sibyte/sb1250.h
index 494aa65..0dad844 100644
--- a/include/asm-mips/sibyte/sb1250.h
+++ b/include/asm-mips/sibyte/sb1250.h
@@ -45,13 +45,11 @@
extern unsigned int periph_rev;
extern unsigned int zbbus_mhz;
-extern void sb1250_hpt_setup(void);
extern void sb1250_time_init(void);
extern void sb1250_mask_irq(int cpu, int irq);
extern void sb1250_unmask_irq(int cpu, int irq);
extern void sb1250_smp_finish(void);
-extern void bcm1480_hpt_setup(void);
extern void bcm1480_time_init(void);
extern void bcm1480_mask_irq(int cpu, int irq);
extern void bcm1480_unmask_irq(int cpu, int irq);