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? */
115 update_process_times(user_mode(regs));
118 * If we have an externally synchronized Linux clock, then update
119 * RTC clock accordingly every ~11 minutes. Set_rtc_mmss() has to be
120 * called as close as possible to when a second starts.
122 if ((time_status & STA_UNSYNC) == 0 &&
123 xtime.tv_sec > last_rtc_update + 660 &&
124 (xtime.tv_nsec / 1000) >= 500000 - ((unsigned) TICK_SIZE) / 2 &&
125 (xtime.tv_nsec / 1000) <= 500000 + ((unsigned) TICK_SIZE) / 2) {
126 if (rtc_set_time(xtime.tv_sec) == 0) {
127 last_rtc_update = xtime.tv_sec;
129 last_rtc_update = xtime.tv_sec - 600;
130 /* do it again in 60 s */
134 write_sequnlock(&xtime_lock);
138 unsigned long ip27_do_gettimeoffset(void)
140 unsigned long ct_cur1;
141 ct_cur1 = REMOTE_HUB_L(cputonasid(0), PI_RT_COUNT) + CYCLES_PER_JIFFY;
142 return (ct_cur1 - ct_cur[0]) * NSEC_PER_CYCLE / 1000;
145 /* Includes for ioc3_init(). */
146 #include <asm/sn/types.h>
147 #include <asm/sn/sn0/addrs.h>
148 #include <asm/sn/sn0/hubni.h>
149 #include <asm/sn/sn0/hubio.h>
150 #include <asm/pci/bridge.h>
152 static __init unsigned long get_m48t35_time(void)
154 unsigned int year, month, date, hour, min, sec;
155 struct m48t35_rtc *rtc;
159 rtc = (struct m48t35_rtc *)(KL_CONFIG_CH_CONS_INFO(nid)->memory_base +
162 rtc->control |= M48T35_RTC_READ;
169 rtc->control &= ~M48T35_RTC_READ;
173 hour = BCD2BIN(hour);
174 date = BCD2BIN(date);
175 month = BCD2BIN(month);
176 year = BCD2BIN(year);
180 return mktime(year, month, date, hour, min, sec);
183 static void ip27_timer_setup(struct irqaction *irq)
185 /* over-write the handler, we use our own way */
186 irq->handler = no_action;
188 /* setup irqaction */
189 // setup_irq(IP27_TIMER_IRQ, irq); /* XXX Can't do this yet. */
192 void __init ip27_time_init(void)
194 xtime.tv_sec = get_m48t35_time();
197 do_gettimeoffset = ip27_do_gettimeoffset;
199 board_timer_setup = ip27_timer_setup;
202 void __init cpu_time_init(void)
208 /* Don't use ARCS. ARCS is fragile. Klconfig is simple and sane. */
209 board = find_lboard(KL_CONFIG_INFO(get_nasid()), KLTYPE_IP27);
211 panic("Can't find board info for myself.");
213 cpuid = LOCAL_HUB_L(PI_CPU_NUM) ? IP27_CPU0_INDEX : IP27_CPU1_INDEX;
214 cpu = (klcpu_t *) KLCF_COMP(board, cpuid);
216 panic("No information about myself?");
218 printk("CPU %d clock is %dMHz.\n", smp_processor_id(), cpu->cpu_speed);
220 set_c0_status(SRB_TIMOCLK);
223 void __init hub_rtc_init(cnodeid_t cnode)
226 * We only need to initialize the current node.
227 * If this is not the current node then it is a cpuless
228 * node and timeouts will not happen there.
230 if (get_compact_nodeid() == cnode) {
231 int cpu = smp_processor_id();
232 LOCAL_HUB_S(PI_RT_EN_A, 1);
233 LOCAL_HUB_S(PI_RT_EN_B, 1);
234 LOCAL_HUB_S(PI_PROF_EN_A, 0);
235 LOCAL_HUB_S(PI_PROF_EN_B, 0);
236 ct_cur[cpu] = CYCLES_PER_JIFFY;
237 LOCAL_HUB_S(PI_RT_COMPARE_A, ct_cur[cpu]);
238 LOCAL_HUB_S(PI_RT_COUNT, 0);
239 LOCAL_HUB_S(PI_RT_PEND_A, 0);
240 LOCAL_HUB_S(PI_RT_COMPARE_B, ct_cur[cpu]);
241 LOCAL_HUB_S(PI_RT_COUNT, 0);
242 LOCAL_HUB_S(PI_RT_PEND_B, 0);