[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>
This commit is contained in:
Ralf Baechle 2007-10-22 10:38:44 +01:00
parent 06d428d719
commit d04533650f
7 changed files with 158 additions and 167 deletions

View file

@ -452,6 +452,43 @@ static void bcm1480_kgdb_interrupt(void)
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 @@ asmlinkage void plat_irq_dispatch(void)
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 @@ asmlinkage void plat_irq_dispatch(void)
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();
}

View file

@ -58,7 +58,7 @@ static void *mailbox_0_regs[] = {
/*
* 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 @@ void bcm1480_smp_init(void)
change_c0_status(ST0_IM, imask);
}
void bcm1480_smp_finish(void)
void __cpuinit bcm1480_smp_finish(void)
{
extern void sb1480_clockevent_init(void);

View file

@ -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 @@ static void sibyte_set_mode(enum clock_event_mode mode,
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 @@ static int sibyte_next_event(unsigned long delta, struct clock_event_device *cd)
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();
}

View file

@ -402,6 +402,22 @@ static void sb1250_kgdb_interrupt(void)
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 @@ asmlinkage void plat_irq_dispatch(void)
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();
}

View file

@ -46,7 +46,7 @@ static void *mailbox_regs[] = {
/*
* 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 @@ void sb1250_smp_init(void)
change_c0_status(ST0_IM, imask);
}
void sb1250_smp_finish(void)
void __cpuinit sb1250_smp_finish(void)
{
extern void sb1250_clockevent_init(void);

View file

@ -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 @@ sibyte_next_event(unsigned long delta, struct clock_event_device *evt)
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 @@ static struct irqaction sibyte_irqaction = {
.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 @@ void __cpuinit sb1250_clockevent_init(void)
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 @@ struct clocksource bcm1250_clocksource = {
.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 @@ void __init sb1250_clocksource_init(void)
{
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);
}

View file

@ -45,13 +45,11 @@ extern unsigned int soc_type;
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);