2 * Copytight (C) 1999, 2000 Ralf Baechle (ralf@gnu.org)
3 * Copytight (C) 1999, 2000 Silicon Graphics, Inc.
6 #include <linux/config.h>
7 #include <linux/init.h>
8 #include <linux/kernel.h>
9 #include <linux/sched.h>
10 #include <linux/interrupt.h>
11 #include <linux/kernel_stat.h>
12 #include <linux/param.h>
13 #include <linux/time.h>
14 #include <linux/timex.h>
18 #include <asm/pgtable.h>
19 #include <asm/sgialib.h>
20 #include <asm/sn/ioc3.h>
21 #include <asm/m48t35.h>
22 #include <asm/sn/klconfig.h>
23 #include <asm/sn/arch.h>
24 #include <asm/sn/addrs.h>
25 #include <asm/sn/sn_private.h>
26 #include <asm/sn/sn0/ip27.h>
27 #include <asm/sn/sn0/hub.h>
30 * This is a hack; we really need to figure these values out dynamically
32 * Since 800 ns works very well with various HUB frequencies, such as
33 * 360, 380, 390 and 400 MHZ, we use 800 ns rtc cycle time.
35 * Ralf: which clock rate is used to feed the counter?
37 #define NSEC_PER_CYCLE 800
38 #define CYCLES_PER_SEC (NSEC_PER_SEC/NSEC_PER_CYCLE)
39 #define CYCLES_PER_JIFFY (CYCLES_PER_SEC/HZ)
41 #define TICK_SIZE (tick_nsec / 1000)
43 static unsigned long ct_cur[NR_CPUS]; /* What counter should be at next timer irq */
44 static long last_rtc_update; /* Last time the rtc clock got updated */
46 extern volatile unsigned long wall_jiffies;
49 static int set_rtc_mmss(unsigned long nowtime)
52 int real_seconds, real_minutes, cmos_minutes;
53 struct m48t35_rtc *rtc;
57 rtc = (struct m48t35_rtc *)(KL_CONFIG_CH_CONS_INFO(nid)->memory_base +
60 rtc->control |= M48T35_RTC_READ;
61 cmos_minutes = BCD2BIN(rtc->min);
62 rtc->control &= ~M48T35_RTC_READ;
65 * Since we're only adjusting minutes and seconds, don't interfere with
66 * hour overflow. This avoids messing with unknown time zones but
67 * requires your RTC not to be off by more than 15 minutes
69 real_seconds = nowtime % 60;
70 real_minutes = nowtime / 60;
71 if (((abs(real_minutes - cmos_minutes) + 15)/30) & 1)
72 real_minutes += 30; /* correct for half hour time zone */
75 if (abs(real_minutes - cmos_minutes) < 30) {
76 real_seconds = BIN2BCD(real_seconds);
77 real_minutes = BIN2BCD(real_minutes);
78 rtc->control |= M48T35_RTC_SET;
79 rtc->sec = real_seconds;
80 rtc->min = real_minutes;
81 rtc->control &= ~M48T35_RTC_SET;
84 "set_rtc_mmss: can't update from %d to %d\n",
85 cmos_minutes, real_minutes);
93 void ip27_rt_timer_interrupt(struct pt_regs *regs)
95 int cpu = smp_processor_id();
96 int cpuA = cputoslice(cpu) == 0;
97 int irq = 9; /* XXX Assign number */
100 write_seqlock(&xtime_lock);
103 LOCAL_HUB_S(cpuA ? PI_RT_PEND_A : PI_RT_PEND_B, 0); /* Ack */
104 ct_cur[cpu] += CYCLES_PER_JIFFY;
105 LOCAL_HUB_S(cpuA ? PI_RT_COMPARE_A : PI_RT_COMPARE_B, ct_cur[cpu]);
107 if (LOCAL_HUB_L(PI_RT_COUNT) >= ct_cur[cpu])
110 kstat_this_cpu.irqs[irq]++; /* kstat only for bootcpu? */
116 update_process_times(user_mode(regs));
117 #endif /* CONFIG_SMP */
120 * If we have an externally synchronized Linux clock, then update
121 * RTC clock accordingly every ~11 minutes. Set_rtc_mmss() has to be
122 * called as close as possible to when a second starts.
124 if ((time_status & STA_UNSYNC) == 0 &&
125 xtime.tv_sec > last_rtc_update + 660 &&
126 (xtime.tv_nsec / 1000) >= 500000 - ((unsigned) TICK_SIZE) / 2 &&
127 (xtime.tv_nsec / 1000) <= 500000 + ((unsigned) TICK_SIZE) / 2) {
128 if (rtc_set_time(xtime.tv_sec) == 0) {
129 last_rtc_update = xtime.tv_sec;
131 last_rtc_update = xtime.tv_sec - 600;
132 /* do it again in 60 s */
136 write_sequnlock(&xtime_lock);
140 unsigned long ip27_do_gettimeoffset(void)
142 unsigned long ct_cur1;
143 ct_cur1 = REMOTE_HUB_L(cputonasid(0), PI_RT_COUNT) + CYCLES_PER_JIFFY;
144 return (ct_cur1 - ct_cur[0]) * NSEC_PER_CYCLE / 1000;
147 /* Includes for ioc3_init(). */
148 #include <asm/sn/types.h>
149 #include <asm/sn/sn0/addrs.h>
150 #include <asm/sn/sn0/hubni.h>
151 #include <asm/sn/sn0/hubio.h>
152 #include <asm/pci/bridge.h>
154 static __init unsigned long get_m48t35_time(void)
156 unsigned int year, month, date, hour, min, sec;
157 struct m48t35_rtc *rtc;
161 rtc = (struct m48t35_rtc *)(KL_CONFIG_CH_CONS_INFO(nid)->memory_base +
164 rtc->control |= M48T35_RTC_READ;
171 rtc->control &= ~M48T35_RTC_READ;
175 hour = BCD2BIN(hour);
176 date = BCD2BIN(date);
177 month = BCD2BIN(month);
178 year = BCD2BIN(year);
182 return mktime(year, month, date, hour, min, sec);
185 static void ip27_timer_setup(struct irqaction *irq)
187 /* over-write the handler, we use our own way */
188 irq->handler = no_action;
190 /* setup irqaction */
191 // setup_irq(IP27_TIMER_IRQ, irq); /* XXX Can't do this yet. */
194 void __init ip27_time_init(void)
196 xtime.tv_sec = get_m48t35_time();
199 do_gettimeoffset = ip27_do_gettimeoffset;
201 board_timer_setup = ip27_timer_setup;
204 void __init cpu_time_init(void)
210 /* Don't use ARCS. ARCS is fragile. Klconfig is simple and sane. */
211 board = find_lboard(KL_CONFIG_INFO(get_nasid()), KLTYPE_IP27);
213 panic("Can't find board info for myself.");
215 cpuid = LOCAL_HUB_L(PI_CPU_NUM) ? IP27_CPU0_INDEX : IP27_CPU1_INDEX;
216 cpu = (klcpu_t *) KLCF_COMP(board, cpuid);
218 panic("No information about myself?");
220 printk("CPU %d clock is %dMHz.\n", smp_processor_id(), cpu->cpu_speed);
222 set_c0_status(SRB_TIMOCLK);
225 void __init hub_rtc_init(cnodeid_t cnode)
228 * We only need to initialize the current node.
229 * If this is not the current node then it is a cpuless
230 * node and timeouts will not happen there.
232 if (get_compact_nodeid() == cnode) {
233 int cpu = smp_processor_id();
234 LOCAL_HUB_S(PI_RT_EN_A, 1);
235 LOCAL_HUB_S(PI_RT_EN_B, 1);
236 LOCAL_HUB_S(PI_PROF_EN_A, 0);
237 LOCAL_HUB_S(PI_PROF_EN_B, 0);
238 ct_cur[cpu] = CYCLES_PER_JIFFY;
239 LOCAL_HUB_S(PI_RT_COMPARE_A, ct_cur[cpu]);
240 LOCAL_HUB_S(PI_RT_COUNT, 0);
241 LOCAL_HUB_S(PI_RT_PEND_A, 0);
242 LOCAL_HUB_S(PI_RT_COMPARE_B, ct_cur[cpu]);
243 LOCAL_HUB_S(PI_RT_COUNT, 0);
244 LOCAL_HUB_S(PI_RT_PEND_B, 0);