1 /*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
4 * for more details.
5 *
6 * Based on linux/arch/mips/kernel/cevt-r4k.c,
7 * linux/arch/mips/jmr3927/rbhma3100/setup.c
8 *
9 * Copyright 2001 MontaVista Software Inc.
10 * Copyright (C) 2000-2001 Toshiba Corporation
11 * Copyright (C) 2007 MIPS Technologies, Inc.
12 * Copyright (C) 2007 Ralf Baechle <ralf@linux-mips.org>
13 */
14 #include <linux/init.h>
15 #include <linux/interrupt.h>
16 #include <asm/time.h>
17 #include <asm/txx9tmr.h>
18
19 #define TCR_BASE (TXx9_TMTCR_CCDE | TXx9_TMTCR_CRE | TXx9_TMTCR_TMODE_ITVL)
20 #define TIMER_CCD 0 /* 1/2 */
21 #define TIMER_CLK(imclk) ((imclk) / (2 << TIMER_CCD))
22
23 static struct txx9_tmr_reg __iomem *txx9_cs_tmrptr;
24
txx9_cs_read(void)25 static cycle_t txx9_cs_read(void)
26 {
27 return __raw_readl(&txx9_cs_tmrptr->trr);
28 }
29
30 /* Use 1 bit smaller width to use full bits in that width */
31 #define TXX9_CLOCKSOURCE_BITS (TXX9_TIMER_BITS - 1)
32
33 static struct clocksource txx9_clocksource = {
34 .name = "TXx9",
35 .rating = 200,
36 .read = txx9_cs_read,
37 .mask = CLOCKSOURCE_MASK(TXX9_CLOCKSOURCE_BITS),
38 .flags = CLOCK_SOURCE_IS_CONTINUOUS,
39 };
40
txx9_clocksource_init(unsigned long baseaddr,unsigned int imbusclk)41 void __init txx9_clocksource_init(unsigned long baseaddr,
42 unsigned int imbusclk)
43 {
44 struct txx9_tmr_reg __iomem *tmrptr;
45
46 clocksource_set_clock(&txx9_clocksource, TIMER_CLK(imbusclk));
47 clocksource_register(&txx9_clocksource);
48
49 tmrptr = ioremap(baseaddr, sizeof(struct txx9_tmr_reg));
50 __raw_writel(TCR_BASE, &tmrptr->tcr);
51 __raw_writel(0, &tmrptr->tisr);
52 __raw_writel(TIMER_CCD, &tmrptr->ccdr);
53 __raw_writel(TXx9_TMITMR_TZCE, &tmrptr->itmr);
54 __raw_writel(1 << TXX9_CLOCKSOURCE_BITS, &tmrptr->cpra);
55 __raw_writel(TCR_BASE | TXx9_TMTCR_TCE, &tmrptr->tcr);
56 txx9_cs_tmrptr = tmrptr;
57 }
58
59 static struct txx9_tmr_reg __iomem *txx9_tmrptr;
60
txx9tmr_stop_and_clear(struct txx9_tmr_reg __iomem * tmrptr)61 static void txx9tmr_stop_and_clear(struct txx9_tmr_reg __iomem *tmrptr)
62 {
63 /* stop and reset counter */
64 __raw_writel(TCR_BASE, &tmrptr->tcr);
65 /* clear pending interrupt */
66 __raw_writel(0, &tmrptr->tisr);
67 }
68
txx9tmr_set_mode(enum clock_event_mode mode,struct clock_event_device * evt)69 static void txx9tmr_set_mode(enum clock_event_mode mode,
70 struct clock_event_device *evt)
71 {
72 struct txx9_tmr_reg __iomem *tmrptr = txx9_tmrptr;
73
74 txx9tmr_stop_and_clear(tmrptr);
75 switch (mode) {
76 case CLOCK_EVT_MODE_PERIODIC:
77 __raw_writel(TXx9_TMITMR_TIIE | TXx9_TMITMR_TZCE,
78 &tmrptr->itmr);
79 /* start timer */
80 __raw_writel(((u64)(NSEC_PER_SEC / HZ) * evt->mult) >>
81 evt->shift,
82 &tmrptr->cpra);
83 __raw_writel(TCR_BASE | TXx9_TMTCR_TCE, &tmrptr->tcr);
84 break;
85 case CLOCK_EVT_MODE_SHUTDOWN:
86 case CLOCK_EVT_MODE_UNUSED:
87 __raw_writel(0, &tmrptr->itmr);
88 break;
89 case CLOCK_EVT_MODE_ONESHOT:
90 __raw_writel(TXx9_TMITMR_TIIE, &tmrptr->itmr);
91 break;
92 case CLOCK_EVT_MODE_RESUME:
93 __raw_writel(TIMER_CCD, &tmrptr->ccdr);
94 __raw_writel(0, &tmrptr->itmr);
95 break;
96 }
97 }
98
txx9tmr_set_next_event(unsigned long delta,struct clock_event_device * evt)99 static int txx9tmr_set_next_event(unsigned long delta,
100 struct clock_event_device *evt)
101 {
102 struct txx9_tmr_reg __iomem *tmrptr = txx9_tmrptr;
103
104 txx9tmr_stop_and_clear(tmrptr);
105 /* start timer */
106 __raw_writel(delta, &tmrptr->cpra);
107 __raw_writel(TCR_BASE | TXx9_TMTCR_TCE, &tmrptr->tcr);
108 return 0;
109 }
110
111 static struct clock_event_device txx9tmr_clock_event_device = {
112 .name = "TXx9",
113 .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
114 .rating = 200,
115 .set_mode = txx9tmr_set_mode,
116 .set_next_event = txx9tmr_set_next_event,
117 };
118
txx9tmr_interrupt(int irq,void * dev_id)119 static irqreturn_t txx9tmr_interrupt(int irq, void *dev_id)
120 {
121 struct clock_event_device *cd = &txx9tmr_clock_event_device;
122 struct txx9_tmr_reg __iomem *tmrptr = txx9_tmrptr;
123
124 __raw_writel(0, &tmrptr->tisr); /* ack interrupt */
125 cd->event_handler(cd);
126 return IRQ_HANDLED;
127 }
128
129 static struct irqaction txx9tmr_irq = {
130 .handler = txx9tmr_interrupt,
131 .flags = IRQF_DISABLED | IRQF_PERCPU,
132 .name = "txx9tmr",
133 };
134
txx9_clockevent_init(unsigned long baseaddr,int irq,unsigned int imbusclk)135 void __init txx9_clockevent_init(unsigned long baseaddr, int irq,
136 unsigned int imbusclk)
137 {
138 struct clock_event_device *cd = &txx9tmr_clock_event_device;
139 struct txx9_tmr_reg __iomem *tmrptr;
140
141 tmrptr = ioremap(baseaddr, sizeof(struct txx9_tmr_reg));
142 txx9tmr_stop_and_clear(tmrptr);
143 __raw_writel(TIMER_CCD, &tmrptr->ccdr);
144 __raw_writel(0, &tmrptr->itmr);
145 txx9_tmrptr = tmrptr;
146
147 clockevent_set_clock(cd, TIMER_CLK(imbusclk));
148 cd->max_delta_ns =
149 clockevent_delta2ns(0xffffffff >> (32 - TXX9_TIMER_BITS), cd);
150 cd->min_delta_ns = clockevent_delta2ns(0xf, cd);
151 cd->irq = irq;
152 cd->cpumask = cpumask_of(0),
153 clockevents_register_device(cd);
154 setup_irq(irq, &txx9tmr_irq);
155 printk(KERN_INFO "TXx9: clockevent device at 0x%lx, irq %d\n",
156 baseaddr, irq);
157 }
158
txx9_tmr_init(unsigned long baseaddr)159 void __init txx9_tmr_init(unsigned long baseaddr)
160 {
161 struct txx9_tmr_reg __iomem *tmrptr;
162
163 tmrptr = ioremap(baseaddr, sizeof(struct txx9_tmr_reg));
164 /* Start once to make CounterResetEnable effective */
165 __raw_writel(TXx9_TMTCR_CRE | TXx9_TMTCR_TCE, &tmrptr->tcr);
166 /* Stop and reset the counter */
167 __raw_writel(TXx9_TMTCR_CRE, &tmrptr->tcr);
168 __raw_writel(0, &tmrptr->tisr);
169 __raw_writel(0xffffffff, &tmrptr->cpra);
170 __raw_writel(0, &tmrptr->itmr);
171 __raw_writel(0, &tmrptr->ccdr);
172 __raw_writel(0, &tmrptr->pgmr);
173 iounmap(tmrptr);
174 }
175