1 /* linux/arch/sparc/kernel/time.c
2  *
3  * Copyright (C) 1995 David S. Miller (davem@davemloft.net)
4  * Copyright (C) 1996 Thomas K. Dyas (tdyas@eden.rutgers.edu)
5  *
6  * Chris Davis (cdavis@cois.on.ca) 03/27/1998
7  * Added support for the intersil on the sun4/4200
8  *
9  * Gleb Raiko (rajko@mech.math.msu.su) 08/18/1998
10  * Support for MicroSPARC-IIep, PCI CPU.
11  *
12  * This file handles the Sparc specific time handling details.
13  *
14  * 1997-09-10	Updated NTP code according to technical memorandum Jan '96
15  *		"A Kernel Model for Precision Timekeeping" by Dave Mills
16  */
17 #include <linux/errno.h>
18 #include <linux/module.h>
19 #include <linux/sched.h>
20 #include <linux/kernel.h>
21 #include <linux/param.h>
22 #include <linux/string.h>
23 #include <linux/mm.h>
24 #include <linux/interrupt.h>
25 #include <linux/time.h>
26 #include <linux/rtc.h>
27 #include <linux/rtc/m48t59.h>
28 #include <linux/timex.h>
29 #include <linux/init.h>
30 #include <linux/pci.h>
31 #include <linux/ioport.h>
32 #include <linux/profile.h>
33 #include <linux/of.h>
34 #include <linux/of_device.h>
35 #include <linux/platform_device.h>
36 
37 #include <asm/oplib.h>
38 #include <asm/timex.h>
39 #include <asm/timer.h>
40 #include <asm/system.h>
41 #include <asm/irq.h>
42 #include <asm/io.h>
43 #include <asm/idprom.h>
44 #include <asm/machines.h>
45 #include <asm/page.h>
46 #include <asm/pcic.h>
47 #include <asm/irq_regs.h>
48 
49 #include "irq.h"
50 
51 DEFINE_SPINLOCK(rtc_lock);
52 EXPORT_SYMBOL(rtc_lock);
53 
54 static int set_rtc_mmss(unsigned long);
55 
profile_pc(struct pt_regs * regs)56 unsigned long profile_pc(struct pt_regs *regs)
57 {
58 	extern char __copy_user_begin[], __copy_user_end[];
59 	extern char __atomic_begin[], __atomic_end[];
60 	extern char __bzero_begin[], __bzero_end[];
61 
62 	unsigned long pc = regs->pc;
63 
64 	if (in_lock_functions(pc) ||
65 	    (pc >= (unsigned long) __copy_user_begin &&
66 	     pc < (unsigned long) __copy_user_end) ||
67 	    (pc >= (unsigned long) __atomic_begin &&
68 	     pc < (unsigned long) __atomic_end) ||
69 	    (pc >= (unsigned long) __bzero_begin &&
70 	     pc < (unsigned long) __bzero_end))
71 		pc = regs->u_regs[UREG_RETPC];
72 	return pc;
73 }
74 
75 EXPORT_SYMBOL(profile_pc);
76 
77 __volatile__ unsigned int *master_l10_counter;
78 
79 u32 (*do_arch_gettimeoffset)(void);
80 
update_persistent_clock(struct timespec now)81 int update_persistent_clock(struct timespec now)
82 {
83 	return set_rtc_mmss(now.tv_sec);
84 }
85 
86 /*
87  * timer_interrupt() needs to keep up the real-time clock,
88  * as well as call the "xtime_update()" routine every clocktick
89  */
90 
91 #define TICK_SIZE (tick_nsec / 1000)
92 
timer_interrupt(int dummy,void * dev_id)93 static irqreturn_t timer_interrupt(int dummy, void *dev_id)
94 {
95 #ifndef CONFIG_SMP
96 	profile_tick(CPU_PROFILING);
97 #endif
98 
99 	clear_clock_irq();
100 
101 	xtime_update(1);
102 
103 #ifndef CONFIG_SMP
104 	update_process_times(user_mode(get_irq_regs()));
105 #endif
106 	return IRQ_HANDLED;
107 }
108 
mostek_read_byte(struct device * dev,u32 ofs)109 static unsigned char mostek_read_byte(struct device *dev, u32 ofs)
110 {
111 	struct platform_device *pdev = to_platform_device(dev);
112 	struct m48t59_plat_data *pdata = pdev->dev.platform_data;
113 
114 	return readb(pdata->ioaddr + ofs);
115 }
116 
mostek_write_byte(struct device * dev,u32 ofs,u8 val)117 static void mostek_write_byte(struct device *dev, u32 ofs, u8 val)
118 {
119 	struct platform_device *pdev = to_platform_device(dev);
120 	struct m48t59_plat_data *pdata = pdev->dev.platform_data;
121 
122 	writeb(val, pdata->ioaddr + ofs);
123 }
124 
125 static struct m48t59_plat_data m48t59_data = {
126 	.read_byte = mostek_read_byte,
127 	.write_byte = mostek_write_byte,
128 };
129 
130 /* resource is set at runtime */
131 static struct platform_device m48t59_rtc = {
132 	.name		= "rtc-m48t59",
133 	.id		= 0,
134 	.num_resources	= 1,
135 	.dev	= {
136 		.platform_data = &m48t59_data,
137 	},
138 };
139 
clock_probe(struct platform_device * op)140 static int __devinit clock_probe(struct platform_device *op)
141 {
142 	struct device_node *dp = op->dev.of_node;
143 	const char *model = of_get_property(dp, "model", NULL);
144 
145 	if (!model)
146 		return -ENODEV;
147 
148 	/* Only the primary RTC has an address property */
149 	if (!of_find_property(dp, "address", NULL))
150 		return -ENODEV;
151 
152 	m48t59_rtc.resource = &op->resource[0];
153 	if (!strcmp(model, "mk48t02")) {
154 		/* Map the clock register io area read-only */
155 		m48t59_data.ioaddr = of_ioremap(&op->resource[0], 0,
156 						2048, "rtc-m48t59");
157 		m48t59_data.type = M48T59RTC_TYPE_M48T02;
158 	} else if (!strcmp(model, "mk48t08")) {
159 		m48t59_data.ioaddr = of_ioremap(&op->resource[0], 0,
160 						8192, "rtc-m48t59");
161 		m48t59_data.type = M48T59RTC_TYPE_M48T08;
162 	} else
163 		return -ENODEV;
164 
165 	if (platform_device_register(&m48t59_rtc) < 0)
166 		printk(KERN_ERR "Registering RTC device failed\n");
167 
168 	return 0;
169 }
170 
171 static struct of_device_id clock_match[] = {
172 	{
173 		.name = "eeprom",
174 	},
175 	{},
176 };
177 
178 static struct platform_driver clock_driver = {
179 	.probe		= clock_probe,
180 	.driver = {
181 		.name = "rtc",
182 		.owner = THIS_MODULE,
183 		.of_match_table = clock_match,
184 	},
185 };
186 
187 
188 /* Probe for the mostek real time clock chip. */
clock_init(void)189 static int __init clock_init(void)
190 {
191 	return platform_driver_register(&clock_driver);
192 }
193 /* Must be after subsys_initcall() so that busses are probed.  Must
194  * be before device_initcall() because things like the RTC driver
195  * need to see the clock registers.
196  */
197 fs_initcall(clock_init);
198 
199 
sbus_do_gettimeoffset(void)200 u32 sbus_do_gettimeoffset(void)
201 {
202 	unsigned long val = *master_l10_counter;
203 	unsigned long usec = (val >> 10) & 0x1fffff;
204 
205 	/* Limit hit?  */
206 	if (val & 0x80000000)
207 		usec += 1000000 / HZ;
208 
209 	return usec * 1000;
210 }
211 
212 
arch_gettimeoffset(void)213 u32 arch_gettimeoffset(void)
214 {
215 	if (unlikely(!do_arch_gettimeoffset))
216 		return 0;
217 	return do_arch_gettimeoffset();
218 }
219 
sbus_time_init(void)220 static void __init sbus_time_init(void)
221 {
222 	do_arch_gettimeoffset = sbus_do_gettimeoffset;
223 
224 	btfixup();
225 
226 	sparc_irq_config.init_timers(timer_interrupt);
227 }
228 
time_init(void)229 void __init time_init(void)
230 {
231 #ifdef CONFIG_PCI
232 	extern void pci_time_init(void);
233 	if (pcic_present()) {
234 		pci_time_init();
235 		return;
236 	}
237 #endif
238 	sbus_time_init();
239 }
240 
241 
set_rtc_mmss(unsigned long secs)242 static int set_rtc_mmss(unsigned long secs)
243 {
244 	struct rtc_device *rtc = rtc_class_open("rtc0");
245 	int err = -1;
246 
247 	if (rtc) {
248 		err = rtc_set_mmss(rtc, secs);
249 		rtc_class_close(rtc);
250 	}
251 
252 	return err;
253 }
254