2 * Copytight (C) 1999, 2000, 05, 06 Ralf Baechle (ralf@linux-mips.org)
3 * Copytight (C) 1999, 2000 Silicon Graphics, Inc.
6 #include <linux/clockchips.h>
7 #include <linux/init.h>
8 #include <linux/kernel.h>
9 #include <linux/sched.h>
10 #include <linux/sched_clock.h>
11 #include <linux/interrupt.h>
12 #include <linux/kernel_stat.h>
13 #include <linux/param.h>
14 #include <linux/smp.h>
15 #include <linux/time.h>
16 #include <linux/timex.h>
18 #include <linux/platform_device.h>
21 #include <asm/pgtable.h>
22 #include <asm/sgialib.h>
23 #include <asm/sn/ioc3.h>
24 #include <asm/sn/klconfig.h>
25 #include <asm/sn/arch.h>
26 #include <asm/sn/addrs.h>
27 #include <asm/sn/sn_private.h>
28 #include <asm/sn/sn0/ip27.h>
29 #include <asm/sn/sn0/hub.h>
31 #define TICK_SIZE (tick_nsec / 1000)
33 /* Includes for ioc3_init(). */
34 #include <asm/sn/types.h>
35 #include <asm/sn/sn0/addrs.h>
36 #include <asm/sn/sn0/hubni.h>
37 #include <asm/sn/sn0/hubio.h>
38 #include <asm/pci/bridge.h>
40 static void enable_rt_irq(struct irq_data *d)
44 static void disable_rt_irq(struct irq_data *d)
48 static struct irq_chip rt_irq_type = {
49 .name = "SN HUB RT timer",
50 .irq_mask = disable_rt_irq,
51 .irq_unmask = enable_rt_irq,
54 static int rt_next_event(unsigned long delta, struct clock_event_device *evt)
56 unsigned int cpu = smp_processor_id();
57 int slice = cputoslice(cpu);
60 cnt = LOCAL_HUB_L(PI_RT_COUNT);
62 LOCAL_HUB_S(PI_RT_COMPARE_A + PI_COUNT_OFFSET * slice, cnt);
64 return LOCAL_HUB_L(PI_RT_COUNT) >= cnt ? -ETIME : 0;
67 unsigned int rt_timer_irq;
69 static DEFINE_PER_CPU(struct clock_event_device, hub_rt_clockevent);
70 static DEFINE_PER_CPU(char [11], hub_rt_name);
72 static irqreturn_t hub_rt_counter_handler(int irq, void *dev_id)
74 unsigned int cpu = smp_processor_id();
75 struct clock_event_device *cd = &per_cpu(hub_rt_clockevent, cpu);
76 int slice = cputoslice(cpu);
81 LOCAL_HUB_S(PI_RT_PEND_A + PI_COUNT_OFFSET * slice, 0);
82 cd->event_handler(cd);
87 struct irqaction hub_rt_irqaction = {
88 .handler = hub_rt_counter_handler,
89 .flags = IRQF_PERCPU | IRQF_TIMER,
94 * This is a hack; we really need to figure these values out dynamically
96 * Since 800 ns works very well with various HUB frequencies, such as
97 * 360, 380, 390 and 400 MHZ, we use 800 ns rtc cycle time.
99 * Ralf: which clock rate is used to feed the counter?
101 #define NSEC_PER_CYCLE 800
102 #define CYCLES_PER_SEC (NSEC_PER_SEC / NSEC_PER_CYCLE)
104 void hub_rt_clock_event_init(void)
106 unsigned int cpu = smp_processor_id();
107 struct clock_event_device *cd = &per_cpu(hub_rt_clockevent, cpu);
108 unsigned char *name = per_cpu(hub_rt_name, cpu);
109 int irq = rt_timer_irq;
111 sprintf(name, "hub-rt %d", cpu);
113 cd->features = CLOCK_EVT_FEAT_ONESHOT;
114 clockevent_set_clock(cd, CYCLES_PER_SEC);
115 cd->max_delta_ns = clockevent_delta2ns(0xfffffffffffff, cd);
116 cd->max_delta_ticks = 0xfffffffffffff;
117 cd->min_delta_ns = clockevent_delta2ns(0x300, cd);
118 cd->min_delta_ticks = 0x300;
121 cd->cpumask = cpumask_of(cpu);
122 cd->set_next_event = rt_next_event;
123 clockevents_register_device(cd);
126 static void __init hub_rt_clock_event_global_init(void)
136 irq = allocate_irqno();
138 panic("Allocation of irq number for timer failed");
139 } while (xchg(&rt_timer_irq, irq));
141 irq_set_chip_and_handler(irq, &rt_irq_type, handle_percpu_irq);
142 setup_irq(irq, &hub_rt_irqaction);
145 static u64 hub_rt_read(struct clocksource *cs)
147 return REMOTE_HUB_L(cputonasid(0), PI_RT_COUNT);
150 struct clocksource hub_rt_clocksource = {
154 .mask = CLOCKSOURCE_MASK(52),
155 .flags = CLOCK_SOURCE_IS_CONTINUOUS,
158 static u64 notrace hub_rt_read_sched_clock(void)
160 return REMOTE_HUB_L(cputonasid(0), PI_RT_COUNT);
163 static void __init hub_rt_clocksource_init(void)
165 struct clocksource *cs = &hub_rt_clocksource;
167 clocksource_register_hz(cs, CYCLES_PER_SEC);
169 sched_clock_register(hub_rt_read_sched_clock, 52, CYCLES_PER_SEC);
172 void __init plat_time_init(void)
174 hub_rt_clocksource_init();
175 hub_rt_clock_event_global_init();
176 hub_rt_clock_event_init();
179 void cpu_time_init(void)
185 /* Don't use ARCS. ARCS is fragile. Klconfig is simple and sane. */
186 board = find_lboard(KL_CONFIG_INFO(get_nasid()), KLTYPE_IP27);
188 panic("Can't find board info for myself.");
190 cpuid = LOCAL_HUB_L(PI_CPU_NUM) ? IP27_CPU0_INDEX : IP27_CPU1_INDEX;
191 cpu = (klcpu_t *) KLCF_COMP(board, cpuid);
193 panic("No information about myself?");
195 printk("CPU %d clock is %dMHz.\n", smp_processor_id(), cpu->cpu_speed);
197 set_c0_status(SRB_TIMOCLK);
200 void hub_rtc_init(cnodeid_t cnode)
204 * We only need to initialize the current node.
205 * If this is not the current node then it is a cpuless
206 * node and timeouts will not happen there.
208 if (get_compact_nodeid() == cnode) {
209 LOCAL_HUB_S(PI_RT_EN_A, 1);
210 LOCAL_HUB_S(PI_RT_EN_B, 1);
211 LOCAL_HUB_S(PI_PROF_EN_A, 0);
212 LOCAL_HUB_S(PI_PROF_EN_B, 0);
213 LOCAL_HUB_S(PI_RT_COUNT, 0);
214 LOCAL_HUB_S(PI_RT_PEND_A, 0);
215 LOCAL_HUB_S(PI_RT_PEND_B, 0);
219 static int __init sgi_ip27_rtc_devinit(void)
223 memset(&res, 0, sizeof(res));
224 res.start = XPHYSADDR(KL_CONFIG_CH_CONS_INFO(master_nasid)->memory_base +
226 res.end = res.start + 32767;
227 res.flags = IORESOURCE_MEM;
229 return IS_ERR(platform_device_register_simple("rtc-m48t35", -1,
234 * kludge make this a device_initcall after ioc3 resource conflicts
237 late_initcall(sgi_ip27_rtc_devinit);