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-rw-r--r--arch/mips/sgi-ip27/ip27-timer.c285
1 files changed, 138 insertions, 147 deletions
diff --git a/arch/mips/sgi-ip27/ip27-timer.c b/arch/mips/sgi-ip27/ip27-timer.c
index cddf1cedf00..1d97eaba0c5 100644
--- a/arch/mips/sgi-ip27/ip27-timer.c
+++ b/arch/mips/sgi-ip27/ip27-timer.c
@@ -1,23 +1,25 @@
/*
- * Copytight (C) 1999, 2000, 05 Ralf Baechle (ralf@linux-mips.org)
+ * Copytight (C) 1999, 2000, 05, 06 Ralf Baechle (ralf@linux-mips.org)
* Copytight (C) 1999, 2000 Silicon Graphics, Inc.
*/
#include <linux/bcd.h>
+#include <linux/clockchips.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/interrupt.h>
#include <linux/kernel_stat.h>
#include <linux/param.h>
+#include <linux/smp.h>
#include <linux/time.h>
#include <linux/timex.h>
#include <linux/mm.h>
+#include <linux/platform_device.h>
#include <asm/time.h>
#include <asm/pgtable.h>
#include <asm/sgialib.h>
#include <asm/sn/ioc3.h>
-#include <asm/m48t35.h>
#include <asm/sn/klconfig.h>
#include <asm/sn/arch.h>
#include <asm/sn/addrs.h>
@@ -25,180 +27,153 @@
#include <asm/sn/sn0/ip27.h>
#include <asm/sn/sn0/hub.h>
-/*
- * This is a hack; we really need to figure these values out dynamically
- *
- * Since 800 ns works very well with various HUB frequencies, such as
- * 360, 380, 390 and 400 MHZ, we use 800 ns rtc cycle time.
- *
- * Ralf: which clock rate is used to feed the counter?
- */
-#define NSEC_PER_CYCLE 800
-#define CYCLES_PER_SEC (NSEC_PER_SEC/NSEC_PER_CYCLE)
-#define CYCLES_PER_JIFFY (CYCLES_PER_SEC/HZ)
-
#define TICK_SIZE (tick_nsec / 1000)
-static unsigned long ct_cur[NR_CPUS]; /* What counter should be at next timer irq */
-static long last_rtc_update; /* Last time the rtc clock got updated */
+/* Includes for ioc3_init(). */
+#include <asm/sn/types.h>
+#include <asm/sn/sn0/addrs.h>
+#include <asm/sn/sn0/hubni.h>
+#include <asm/sn/sn0/hubio.h>
+#include <asm/pci/bridge.h>
-extern volatile unsigned long wall_jiffies;
+static void enable_rt_irq(struct irq_data *d)
+{
+}
-#if 0
-static int set_rtc_mmss(unsigned long nowtime)
+static void disable_rt_irq(struct irq_data *d)
{
- int retval = 0;
- int real_seconds, real_minutes, cmos_minutes;
- struct m48t35_rtc *rtc;
- nasid_t nid;
+}
- nid = get_nasid();
- rtc = (struct m48t35_rtc *)(KL_CONFIG_CH_CONS_INFO(nid)->memory_base +
- IOC3_BYTEBUS_DEV0);
+static struct irq_chip rt_irq_type = {
+ .name = "SN HUB RT timer",
+ .irq_mask = disable_rt_irq,
+ .irq_unmask = enable_rt_irq,
+};
- rtc->control |= M48T35_RTC_READ;
- cmos_minutes = BCD2BIN(rtc->min);
- rtc->control &= ~M48T35_RTC_READ;
+static int rt_next_event(unsigned long delta, struct clock_event_device *evt)
+{
+ unsigned int cpu = smp_processor_id();
+ int slice = cputoslice(cpu);
+ unsigned long cnt;
- /*
- * Since we're only adjusting minutes and seconds, don't interfere with
- * hour overflow. This avoids messing with unknown time zones but
- * requires your RTC not to be off by more than 15 minutes
- */
- real_seconds = nowtime % 60;
- real_minutes = nowtime / 60;
- if (((abs(real_minutes - cmos_minutes) + 15)/30) & 1)
- real_minutes += 30; /* correct for half hour time zone */
- real_minutes %= 60;
-
- if (abs(real_minutes - cmos_minutes) < 30) {
- real_seconds = BIN2BCD(real_seconds);
- real_minutes = BIN2BCD(real_minutes);
- rtc->control |= M48T35_RTC_SET;
- rtc->sec = real_seconds;
- rtc->min = real_minutes;
- rtc->control &= ~M48T35_RTC_SET;
- } else {
- printk(KERN_WARNING
- "set_rtc_mmss: can't update from %d to %d\n",
- cmos_minutes, real_minutes);
- retval = -1;
- }
+ cnt = LOCAL_HUB_L(PI_RT_COUNT);
+ cnt += delta;
+ LOCAL_HUB_S(PI_RT_COMPARE_A + PI_COUNT_OFFSET * slice, cnt);
- return retval;
+ return LOCAL_HUB_L(PI_RT_COUNT) >= cnt ? -ETIME : 0;
}
-#endif
-void ip27_rt_timer_interrupt(struct pt_regs *regs)
+static void rt_set_mode(enum clock_event_mode mode,
+ struct clock_event_device *evt)
{
- int cpu = smp_processor_id();
- int cpuA = cputoslice(cpu) == 0;
- int irq = 9; /* XXX Assign number */
-
- irq_enter();
- write_seqlock(&xtime_lock);
-
-again:
- LOCAL_HUB_S(cpuA ? PI_RT_PEND_A : PI_RT_PEND_B, 0); /* Ack */
- ct_cur[cpu] += CYCLES_PER_JIFFY;
- LOCAL_HUB_S(cpuA ? PI_RT_COMPARE_A : PI_RT_COMPARE_B, ct_cur[cpu]);
-
- if (LOCAL_HUB_L(PI_RT_COUNT) >= ct_cur[cpu])
- goto again;
+ /* Nothing to do ... */
+}
- kstat_this_cpu.irqs[irq]++; /* kstat only for bootcpu? */
+unsigned int rt_timer_irq;
- if (cpu == 0)
- do_timer(regs);
+static DEFINE_PER_CPU(struct clock_event_device, hub_rt_clockevent);
+static DEFINE_PER_CPU(char [11], hub_rt_name);
- update_process_times(user_mode(regs));
+static irqreturn_t hub_rt_counter_handler(int irq, void *dev_id)
+{
+ unsigned int cpu = smp_processor_id();
+ struct clock_event_device *cd = &per_cpu(hub_rt_clockevent, cpu);
+ int slice = cputoslice(cpu);
/*
- * If we have an externally synchronized Linux clock, then update
- * RTC clock accordingly every ~11 minutes. Set_rtc_mmss() has to be
- * called as close as possible to when a second starts.
+ * Ack
*/
- if (ntp_synced() &&
- xtime.tv_sec > last_rtc_update + 660 &&
- (xtime.tv_nsec / 1000) >= 500000 - ((unsigned) TICK_SIZE) / 2 &&
- (xtime.tv_nsec / 1000) <= 500000 + ((unsigned) TICK_SIZE) / 2) {
- if (rtc_set_time(xtime.tv_sec) == 0) {
- last_rtc_update = xtime.tv_sec;
- } else {
- last_rtc_update = xtime.tv_sec - 600;
- /* do it again in 60 s */
- }
- }
+ LOCAL_HUB_S(PI_RT_PEND_A + PI_COUNT_OFFSET * slice, 0);
+ cd->event_handler(cd);
- write_sequnlock(&xtime_lock);
- irq_exit();
+ return IRQ_HANDLED;
}
-unsigned long ip27_do_gettimeoffset(void)
-{
- unsigned long ct_cur1;
- ct_cur1 = REMOTE_HUB_L(cputonasid(0), PI_RT_COUNT) + CYCLES_PER_JIFFY;
- return (ct_cur1 - ct_cur[0]) * NSEC_PER_CYCLE / 1000;
-}
+struct irqaction hub_rt_irqaction = {
+ .handler = hub_rt_counter_handler,
+ .flags = IRQF_PERCPU | IRQF_TIMER,
+ .name = "hub-rt",
+};
-/* Includes for ioc3_init(). */
-#include <asm/sn/types.h>
-#include <asm/sn/sn0/addrs.h>
-#include <asm/sn/sn0/hubni.h>
-#include <asm/sn/sn0/hubio.h>
-#include <asm/pci/bridge.h>
+/*
+ * This is a hack; we really need to figure these values out dynamically
+ *
+ * Since 800 ns works very well with various HUB frequencies, such as
+ * 360, 380, 390 and 400 MHZ, we use 800 ns rtc cycle time.
+ *
+ * Ralf: which clock rate is used to feed the counter?
+ */
+#define NSEC_PER_CYCLE 800
+#define CYCLES_PER_SEC (NSEC_PER_SEC / NSEC_PER_CYCLE)
-static __init unsigned long get_m48t35_time(void)
+void hub_rt_clock_event_init(void)
{
- unsigned int year, month, date, hour, min, sec;
- struct m48t35_rtc *rtc;
- nasid_t nid;
-
- nid = get_nasid();
- rtc = (struct m48t35_rtc *)(KL_CONFIG_CH_CONS_INFO(nid)->memory_base +
- IOC3_BYTEBUS_DEV0);
-
- rtc->control |= M48T35_RTC_READ;
- sec = rtc->sec;
- min = rtc->min;
- hour = rtc->hour;
- date = rtc->date;
- month = rtc->month;
- year = rtc->year;
- rtc->control &= ~M48T35_RTC_READ;
-
- sec = BCD2BIN(sec);
- min = BCD2BIN(min);
- hour = BCD2BIN(hour);
- date = BCD2BIN(date);
- month = BCD2BIN(month);
- year = BCD2BIN(year);
-
- year += 1970;
-
- return mktime(year, month, date, hour, min, sec);
+ unsigned int cpu = smp_processor_id();
+ struct clock_event_device *cd = &per_cpu(hub_rt_clockevent, cpu);
+ unsigned char *name = per_cpu(hub_rt_name, cpu);
+ int irq = rt_timer_irq;
+
+ sprintf(name, "hub-rt %d", cpu);
+ cd->name = name;
+ cd->features = CLOCK_EVT_FEAT_ONESHOT;
+ clockevent_set_clock(cd, CYCLES_PER_SEC);
+ cd->max_delta_ns = clockevent_delta2ns(0xfffffffffffff, cd);
+ cd->min_delta_ns = clockevent_delta2ns(0x300, cd);
+ cd->rating = 200;
+ cd->irq = irq;
+ cd->cpumask = cpumask_of(cpu);
+ cd->set_next_event = rt_next_event;
+ cd->set_mode = rt_set_mode;
+ clockevents_register_device(cd);
}
-static void ip27_timer_setup(struct irqaction *irq)
+static void __init hub_rt_clock_event_global_init(void)
{
- /* over-write the handler, we use our own way */
- irq->handler = no_action;
+ int irq;
+
+ do {
+ smp_wmb();
+ irq = rt_timer_irq;
+ if (irq)
+ break;
+
+ irq = allocate_irqno();
+ if (irq < 0)
+ panic("Allocation of irq number for timer failed");
+ } while (xchg(&rt_timer_irq, irq));
- /* setup irqaction */
-// setup_irq(IP27_TIMER_IRQ, irq); /* XXX Can't do this yet. */
+ irq_set_chip_and_handler(irq, &rt_irq_type, handle_percpu_irq);
+ setup_irq(irq, &hub_rt_irqaction);
}
-void __init ip27_time_init(void)
+static cycle_t hub_rt_read(struct clocksource *cs)
{
- xtime.tv_sec = get_m48t35_time();
- xtime.tv_nsec = 0;
+ return REMOTE_HUB_L(cputonasid(0), PI_RT_COUNT);
+}
+
+struct clocksource hub_rt_clocksource = {
+ .name = "HUB-RT",
+ .rating = 200,
+ .read = hub_rt_read,
+ .mask = CLOCKSOURCE_MASK(52),
+ .flags = CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+static void __init hub_rt_clocksource_init(void)
+{
+ struct clocksource *cs = &hub_rt_clocksource;
- do_gettimeoffset = ip27_do_gettimeoffset;
+ clocksource_register_hz(cs, CYCLES_PER_SEC);
+}
- board_timer_setup = ip27_timer_setup;
+void __init plat_time_init(void)
+{
+ hub_rt_clocksource_init();
+ hub_rt_clock_event_global_init();
+ hub_rt_clock_event_init();
}
-void __init cpu_time_init(void)
+void cpu_time_init(void)
{
lboard_t *board;
klcpu_t *cpu;
@@ -219,25 +194,41 @@ void __init cpu_time_init(void)
set_c0_status(SRB_TIMOCLK);
}
-void __init hub_rtc_init(cnodeid_t cnode)
+void hub_rtc_init(cnodeid_t cnode)
{
+
/*
* We only need to initialize the current node.
* If this is not the current node then it is a cpuless
* node and timeouts will not happen there.
*/
if (get_compact_nodeid() == cnode) {
- int cpu = smp_processor_id();
LOCAL_HUB_S(PI_RT_EN_A, 1);
LOCAL_HUB_S(PI_RT_EN_B, 1);
LOCAL_HUB_S(PI_PROF_EN_A, 0);
LOCAL_HUB_S(PI_PROF_EN_B, 0);
- ct_cur[cpu] = CYCLES_PER_JIFFY;
- LOCAL_HUB_S(PI_RT_COMPARE_A, ct_cur[cpu]);
LOCAL_HUB_S(PI_RT_COUNT, 0);
LOCAL_HUB_S(PI_RT_PEND_A, 0);
- LOCAL_HUB_S(PI_RT_COMPARE_B, ct_cur[cpu]);
- LOCAL_HUB_S(PI_RT_COUNT, 0);
LOCAL_HUB_S(PI_RT_PEND_B, 0);
}
}
+
+static int __init sgi_ip27_rtc_devinit(void)
+{
+ struct resource res;
+
+ memset(&res, 0, sizeof(res));
+ res.start = XPHYSADDR(KL_CONFIG_CH_CONS_INFO(master_nasid)->memory_base +
+ IOC3_BYTEBUS_DEV0);
+ res.end = res.start + 32767;
+ res.flags = IORESOURCE_MEM;
+
+ return IS_ERR(platform_device_register_simple("rtc-m48t35", -1,
+ &res, 1));
+}
+
+/*
+ * kludge make this a device_initcall after ioc3 resource conflicts
+ * are resolved
+ */
+late_initcall(sgi_ip27_rtc_devinit);
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-12-05 21:00:41 +0000