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 <linux/irq.h>
17 #include <asm/time.h>
18 #include <asm/txx9tmr.h>
19
20 #define TCR_BASE (TXx9_TMTCR_CCDE | TXx9_TMTCR_CRE | TXx9_TMTCR_TMODE_ITVL)
21 #define TIMER_CCD 0 /* 1/2 */
22 #define TIMER_CLK(imclk) ((imclk) / (2 << TIMER_CCD))
23
24 struct txx9_clocksource {
25 struct clocksource cs;
26 struct txx9_tmr_reg __iomem *tmrptr;
27 };
28
txx9_cs_read(struct clocksource * cs)29 static cycle_t txx9_cs_read(struct clocksource *cs)
30 {
31 struct txx9_clocksource *txx9_cs =
32 container_of(cs, struct txx9_clocksource, cs);
33 return __raw_readl(&txx9_cs->tmrptr->trr);
34 }
35
36 /* Use 1 bit smaller width to use full bits in that width */
37 #define TXX9_CLOCKSOURCE_BITS (TXX9_TIMER_BITS - 1)
38
39 static struct txx9_clocksource txx9_clocksource = {
40 .cs = {
41 .name = "TXx9",
42 .rating = 200,
43 .read = txx9_cs_read,
44 .mask = CLOCKSOURCE_MASK(TXX9_CLOCKSOURCE_BITS),
45 .flags = CLOCK_SOURCE_IS_CONTINUOUS,
46 },
47 };
48
txx9_clocksource_init(unsigned long baseaddr,unsigned int imbusclk)49 void __init txx9_clocksource_init(unsigned long baseaddr,
50 unsigned int imbusclk)
51 {
52 struct txx9_tmr_reg __iomem *tmrptr;
53
54 clocksource_register_hz(&txx9_clocksource.cs, TIMER_CLK(imbusclk));
55
56 tmrptr = ioremap(baseaddr, sizeof(struct txx9_tmr_reg));
57 __raw_writel(TCR_BASE, &tmrptr->tcr);
58 __raw_writel(0, &tmrptr->tisr);
59 __raw_writel(TIMER_CCD, &tmrptr->ccdr);
60 __raw_writel(TXx9_TMITMR_TZCE, &tmrptr->itmr);
61 __raw_writel(1 << TXX9_CLOCKSOURCE_BITS, &tmrptr->cpra);
62 __raw_writel(TCR_BASE | TXx9_TMTCR_TCE, &tmrptr->tcr);
63 txx9_clocksource.tmrptr = tmrptr;
64 }
65
66 struct txx9_clock_event_device {
67 struct clock_event_device cd;
68 struct txx9_tmr_reg __iomem *tmrptr;
69 };
70
txx9tmr_stop_and_clear(struct txx9_tmr_reg __iomem * tmrptr)71 static void txx9tmr_stop_and_clear(struct txx9_tmr_reg __iomem *tmrptr)
72 {
73 /* stop and reset counter */
74 __raw_writel(TCR_BASE, &tmrptr->tcr);
75 /* clear pending interrupt */
76 __raw_writel(0, &tmrptr->tisr);
77 }
78
txx9tmr_set_mode(enum clock_event_mode mode,struct clock_event_device * evt)79 static void txx9tmr_set_mode(enum clock_event_mode mode,
80 struct clock_event_device *evt)
81 {
82 struct txx9_clock_event_device *txx9_cd =
83 container_of(evt, struct txx9_clock_event_device, cd);
84 struct txx9_tmr_reg __iomem *tmrptr = txx9_cd->tmrptr;
85
86 txx9tmr_stop_and_clear(tmrptr);
87 switch (mode) {
88 case CLOCK_EVT_MODE_PERIODIC:
89 __raw_writel(TXx9_TMITMR_TIIE | TXx9_TMITMR_TZCE,
90 &tmrptr->itmr);
91 /* start timer */
92 __raw_writel(((u64)(NSEC_PER_SEC / HZ) * evt->mult) >>
93 evt->shift,
94 &tmrptr->cpra);
95 __raw_writel(TCR_BASE | TXx9_TMTCR_TCE, &tmrptr->tcr);
96 break;
97 case CLOCK_EVT_MODE_SHUTDOWN:
98 case CLOCK_EVT_MODE_UNUSED:
99 __raw_writel(0, &tmrptr->itmr);
100 break;
101 case CLOCK_EVT_MODE_ONESHOT:
102 __raw_writel(TXx9_TMITMR_TIIE, &tmrptr->itmr);
103 break;
104 case CLOCK_EVT_MODE_RESUME:
105 __raw_writel(TIMER_CCD, &tmrptr->ccdr);
106 __raw_writel(0, &tmrptr->itmr);
107 break;
108 }
109 }
110
txx9tmr_set_next_event(unsigned long delta,struct clock_event_device * evt)111 static int txx9tmr_set_next_event(unsigned long delta,
112 struct clock_event_device *evt)
113 {
114 struct txx9_clock_event_device *txx9_cd =
115 container_of(evt, struct txx9_clock_event_device, cd);
116 struct txx9_tmr_reg __iomem *tmrptr = txx9_cd->tmrptr;
117
118 txx9tmr_stop_and_clear(tmrptr);
119 /* start timer */
120 __raw_writel(delta, &tmrptr->cpra);
121 __raw_writel(TCR_BASE | TXx9_TMTCR_TCE, &tmrptr->tcr);
122 return 0;
123 }
124
125 static struct txx9_clock_event_device txx9_clock_event_device = {
126 .cd = {
127 .name = "TXx9",
128 .features = CLOCK_EVT_FEAT_PERIODIC |
129 CLOCK_EVT_FEAT_ONESHOT,
130 .rating = 200,
131 .set_mode = txx9tmr_set_mode,
132 .set_next_event = txx9tmr_set_next_event,
133 },
134 };
135
txx9tmr_interrupt(int irq,void * dev_id)136 static irqreturn_t txx9tmr_interrupt(int irq, void *dev_id)
137 {
138 struct txx9_clock_event_device *txx9_cd = dev_id;
139 struct clock_event_device *cd = &txx9_cd->cd;
140 struct txx9_tmr_reg __iomem *tmrptr = txx9_cd->tmrptr;
141
142 __raw_writel(0, &tmrptr->tisr); /* ack interrupt */
143 cd->event_handler(cd);
144 return IRQ_HANDLED;
145 }
146
147 static struct irqaction txx9tmr_irq = {
148 .handler = txx9tmr_interrupt,
149 .flags = IRQF_PERCPU | IRQF_TIMER,
150 .name = "txx9tmr",
151 .dev_id = &txx9_clock_event_device,
152 };
153
txx9_clockevent_init(unsigned long baseaddr,int irq,unsigned int imbusclk)154 void __init txx9_clockevent_init(unsigned long baseaddr, int irq,
155 unsigned int imbusclk)
156 {
157 struct clock_event_device *cd = &txx9_clock_event_device.cd;
158 struct txx9_tmr_reg __iomem *tmrptr;
159
160 tmrptr = ioremap(baseaddr, sizeof(struct txx9_tmr_reg));
161 txx9tmr_stop_and_clear(tmrptr);
162 __raw_writel(TIMER_CCD, &tmrptr->ccdr);
163 __raw_writel(0, &tmrptr->itmr);
164 txx9_clock_event_device.tmrptr = tmrptr;
165
166 clockevent_set_clock(cd, TIMER_CLK(imbusclk));
167 cd->max_delta_ns =
168 clockevent_delta2ns(0xffffffff >> (32 - TXX9_TIMER_BITS), cd);
169 cd->min_delta_ns = clockevent_delta2ns(0xf, cd);
170 cd->irq = irq;
171 cd->cpumask = cpumask_of(0),
172 clockevents_register_device(cd);
173 setup_irq(irq, &txx9tmr_irq);
174 printk(KERN_INFO "TXx9: clockevent device at 0x%lx, irq %d\n",
175 baseaddr, irq);
176 }
177
txx9_tmr_init(unsigned long baseaddr)178 void __init txx9_tmr_init(unsigned long baseaddr)
179 {
180 struct txx9_tmr_reg __iomem *tmrptr;
181
182 tmrptr = ioremap(baseaddr, sizeof(struct txx9_tmr_reg));
183 /* Start once to make CounterResetEnable effective */
184 __raw_writel(TXx9_TMTCR_CRE | TXx9_TMTCR_TCE, &tmrptr->tcr);
185 /* Stop and reset the counter */
186 __raw_writel(TXx9_TMTCR_CRE, &tmrptr->tcr);
187 __raw_writel(0, &tmrptr->tisr);
188 __raw_writel(0xffffffff, &tmrptr->cpra);
189 __raw_writel(0, &tmrptr->itmr);
190 __raw_writel(0, &tmrptr->ccdr);
191 __raw_writel(0, &tmrptr->pgmr);
192 iounmap(tmrptr);
193 }
194