2 * Copytight (C) 1999, 2000, 05, 06 Ralf Baechle (ralf@linux-mips.org)
3 * Copytight (C) 1999, 2000 Silicon Graphics, Inc.
6 #include <linux/init.h>
7 #include <linux/kernel.h>
8 #include <linux/sched.h>
9 #include <linux/interrupt.h>
10 #include <linux/kernel_stat.h>
11 #include <linux/param.h>
12 #include <linux/time.h>
13 #include <linux/timex.h>
17 #include <asm/pgtable.h>
18 #include <asm/sgialib.h>
19 #include <asm/sn/ioc3.h>
20 #include <asm/m48t35.h>
21 #include <asm/sn/klconfig.h>
22 #include <asm/sn/arch.h>
23 #include <asm/sn/addrs.h>
24 #include <asm/sn/sn_private.h>
25 #include <asm/sn/sn0/ip27.h>
26 #include <asm/sn/sn0/hub.h>
29 * This is a hack; we really need to figure these values out dynamically
31 * Since 800 ns works very well with various HUB frequencies, such as
32 * 360, 380, 390 and 400 MHZ, we use 800 ns rtc cycle time.
34 * Ralf: which clock rate is used to feed the counter?
36 #define NSEC_PER_CYCLE 800
37 #define CYCLES_PER_SEC (NSEC_PER_SEC/NSEC_PER_CYCLE)
38 #define CYCLES_PER_JIFFY (CYCLES_PER_SEC/HZ)
40 #define TICK_SIZE (tick_nsec / 1000)
42 static unsigned long ct_cur[NR_CPUS]; /* What counter should be at next timer irq */
43 static long last_rtc_update; /* Last time the rtc clock got updated */
46 static int set_rtc_mmss(unsigned long nowtime)
49 int real_seconds, real_minutes, cmos_minutes;
50 struct m48t35_rtc *rtc;
54 rtc = (struct m48t35_rtc *)(KL_CONFIG_CH_CONS_INFO(nid)->memory_base +
57 rtc->control |= M48T35_RTC_READ;
58 cmos_minutes = BCD2BIN(rtc->min);
59 rtc->control &= ~M48T35_RTC_READ;
62 * Since we're only adjusting minutes and seconds, don't interfere with
63 * hour overflow. This avoids messing with unknown time zones but
64 * requires your RTC not to be off by more than 15 minutes
66 real_seconds = nowtime % 60;
67 real_minutes = nowtime / 60;
68 if (((abs(real_minutes - cmos_minutes) + 15)/30) & 1)
69 real_minutes += 30; /* correct for half hour time zone */
72 if (abs(real_minutes - cmos_minutes) < 30) {
73 real_seconds = BIN2BCD(real_seconds);
74 real_minutes = BIN2BCD(real_minutes);
75 rtc->control |= M48T35_RTC_SET;
76 rtc->sec = real_seconds;
77 rtc->min = real_minutes;
78 rtc->control &= ~M48T35_RTC_SET;
81 "set_rtc_mmss: can't update from %d to %d\n",
82 cmos_minutes, real_minutes);
90 static unsigned int rt_timer_irq;
92 void ip27_rt_timer_interrupt(struct pt_regs *regs)
94 int cpu = smp_processor_id();
95 int cpuA = cputoslice(cpu) == 0;
96 unsigned int irq = rt_timer_irq;
99 write_seqlock(&xtime_lock);
102 LOCAL_HUB_S(cpuA ? PI_RT_PEND_A : PI_RT_PEND_B, 0); /* Ack */
103 ct_cur[cpu] += CYCLES_PER_JIFFY;
104 LOCAL_HUB_S(cpuA ? PI_RT_COMPARE_A : PI_RT_COMPARE_B, ct_cur[cpu]);
106 if (LOCAL_HUB_L(PI_RT_COUNT) >= ct_cur[cpu])
109 kstat_this_cpu.irqs[irq]++; /* kstat only for bootcpu? */
114 update_process_times(user_mode(regs));
117 * If we have an externally synchronized Linux clock, then update
118 * RTC clock accordingly every ~11 minutes. Set_rtc_mmss() has to be
119 * called as close as possible to when a second starts.
122 xtime.tv_sec > last_rtc_update + 660 &&
123 (xtime.tv_nsec / 1000) >= 500000 - ((unsigned) TICK_SIZE) / 2 &&
124 (xtime.tv_nsec / 1000) <= 500000 + ((unsigned) TICK_SIZE) / 2) {
125 if (rtc_mips_set_time(xtime.tv_sec) == 0) {
126 last_rtc_update = xtime.tv_sec;
128 last_rtc_update = xtime.tv_sec - 600;
129 /* do it again in 60 s */
133 write_sequnlock(&xtime_lock);
137 unsigned long ip27_do_gettimeoffset(void)
139 unsigned long ct_cur1;
140 ct_cur1 = REMOTE_HUB_L(cputonasid(0), PI_RT_COUNT) + CYCLES_PER_JIFFY;
141 return (ct_cur1 - ct_cur[0]) * NSEC_PER_CYCLE / 1000;
144 /* Includes for ioc3_init(). */
145 #include <asm/sn/types.h>
146 #include <asm/sn/sn0/addrs.h>
147 #include <asm/sn/sn0/hubni.h>
148 #include <asm/sn/sn0/hubio.h>
149 #include <asm/pci/bridge.h>
151 static __init unsigned long get_m48t35_time(void)
153 unsigned int year, month, date, hour, min, sec;
154 struct m48t35_rtc *rtc;
158 rtc = (struct m48t35_rtc *)(KL_CONFIG_CH_CONS_INFO(nid)->memory_base +
161 rtc->control |= M48T35_RTC_READ;
168 rtc->control &= ~M48T35_RTC_READ;
172 hour = BCD2BIN(hour);
173 date = BCD2BIN(date);
174 month = BCD2BIN(month);
175 year = BCD2BIN(year);
179 return mktime(year, month, date, hour, min, sec);
182 static unsigned int startup_rt_irq(unsigned int irq)
187 static void shutdown_rt_irq(unsigned int irq)
191 static void enable_rt_irq(unsigned int irq)
195 static void disable_rt_irq(unsigned int irq)
199 static void mask_and_ack_rt(unsigned int irq)
203 static void end_rt_irq(unsigned int irq)
207 static struct irq_chip rt_irq_type = {
208 .typename = "SN HUB RT timer",
209 .startup = startup_rt_irq,
210 .shutdown = shutdown_rt_irq,
211 .enable = enable_rt_irq,
212 .disable = disable_rt_irq,
213 .ack = mask_and_ack_rt,
217 static struct irqaction rt_irqaction = {
218 .handler = ip27_rt_timer_interrupt,
219 .flags = IRQF_DISABLED,
220 .mask = CPU_MASK_NONE,
224 extern int allocate_irqno(void);
226 void __init plat_timer_setup(struct irqaction *irq)
228 int irqno = allocate_irqno();
231 panic("Can't allocate interrupt number for timer interrupt");
233 irq_desc[irqno].status = IRQ_DISABLED;
234 irq_desc[irqno].action = NULL;
235 irq_desc[irqno].depth = 1;
236 irq_desc[irqno].chip = &rt_irq_type;
238 /* over-write the handler, we use our own way */
239 irq->handler = no_action;
241 /* setup irqaction */
242 irq_desc[irqno].status |= IRQ_PER_CPU;
244 rt_timer_irq = irqno;
246 * Only needed to get /proc/interrupt to display timer irq stats
248 setup_irq(irqno, &rt_irqaction);
251 void __init ip27_time_init(void)
253 xtime.tv_sec = get_m48t35_time();
256 do_gettimeoffset = ip27_do_gettimeoffset;
259 void __init cpu_time_init(void)
265 /* Don't use ARCS. ARCS is fragile. Klconfig is simple and sane. */
266 board = find_lboard(KL_CONFIG_INFO(get_nasid()), KLTYPE_IP27);
268 panic("Can't find board info for myself.");
270 cpuid = LOCAL_HUB_L(PI_CPU_NUM) ? IP27_CPU0_INDEX : IP27_CPU1_INDEX;
271 cpu = (klcpu_t *) KLCF_COMP(board, cpuid);
273 panic("No information about myself?");
275 printk("CPU %d clock is %dMHz.\n", smp_processor_id(), cpu->cpu_speed);
277 set_c0_status(SRB_TIMOCLK);
280 void __init hub_rtc_init(cnodeid_t cnode)
283 * We only need to initialize the current node.
284 * If this is not the current node then it is a cpuless
285 * node and timeouts will not happen there.
287 if (get_compact_nodeid() == cnode) {
288 int cpu = smp_processor_id();
289 LOCAL_HUB_S(PI_RT_EN_A, 1);
290 LOCAL_HUB_S(PI_RT_EN_B, 1);
291 LOCAL_HUB_S(PI_PROF_EN_A, 0);
292 LOCAL_HUB_S(PI_PROF_EN_B, 0);
293 ct_cur[cpu] = CYCLES_PER_JIFFY;
294 LOCAL_HUB_S(PI_RT_COMPARE_A, ct_cur[cpu]);
295 LOCAL_HUB_S(PI_RT_COUNT, 0);
296 LOCAL_HUB_S(PI_RT_PEND_A, 0);
297 LOCAL_HUB_S(PI_RT_COMPARE_B, ct_cur[cpu]);
298 LOCAL_HUB_S(PI_RT_COUNT, 0);
299 LOCAL_HUB_S(PI_RT_PEND_B, 0);