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authorAtsushi Nemoto <anemo@mba.ocn.ne.jp>2007-10-24 12:34:09 -0400
committerRalf Baechle <ralf@linux-mips.org>2007-10-29 15:35:35 -0400
commit229f773ef4ee852ad7bfbe8e1238a2c35b2baa6f (patch)
tree44d9dd3f2be845140024883db13ab879b4ce1f2e /arch/mips/kernel/cevt-txx9.c
parent22df3f53e33d55335e1ef43d4e6ead54b379b3a2 (diff)
[MIPS] txx9tmr clockevent/clocksource driver
Convert jmr3927_clock_event_device to more generic txx9tmr_clock_event_device which supports one-shot mode. The txx9tmr_clock_event_device can be used for TX49 too if the cp0 timer interrupt was not available. Convert jmr3927_hpt_read to txx9_clocksource driver which does not depends jiffies anymore. The txx9_clocksource itself can be used for TX49, but normally TX49 uses higher precision clocksource_mips. Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'arch/mips/kernel/cevt-txx9.c')
-rw-r--r--arch/mips/kernel/cevt-txx9.c171
1 files changed, 171 insertions, 0 deletions
diff --git a/arch/mips/kernel/cevt-txx9.c b/arch/mips/kernel/cevt-txx9.c
new file mode 100644
index 000000000000..795cb8fb0d74
--- /dev/null
+++ b/arch/mips/kernel/cevt-txx9.c
@@ -0,0 +1,171 @@
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
23static struct txx9_tmr_reg __iomem *txx9_cs_tmrptr;
24
25static 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
33static 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
41void __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
59static struct txx9_tmr_reg __iomem *txx9_tmrptr;
60
61static 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
69static 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
99static 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
111static 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 .cpumask = CPU_MASK_CPU0,
116 .set_mode = txx9tmr_set_mode,
117 .set_next_event = txx9tmr_set_next_event,
118};
119
120static irqreturn_t txx9tmr_interrupt(int irq, void *dev_id)
121{
122 struct clock_event_device *cd = &txx9tmr_clock_event_device;
123 struct txx9_tmr_reg __iomem *tmrptr = txx9_tmrptr;
124
125 __raw_writel(0, &tmrptr->tisr); /* ack interrupt */
126 cd->event_handler(cd);
127 return IRQ_HANDLED;
128}
129
130static struct irqaction txx9tmr_irq = {
131 .handler = txx9tmr_interrupt,
132 .flags = IRQF_DISABLED | IRQF_PERCPU,
133 .name = "txx9tmr",
134};
135
136void __init txx9_clockevent_init(unsigned long baseaddr, int irq,
137 unsigned int imbusclk)
138{
139 struct clock_event_device *cd = &txx9tmr_clock_event_device;
140 struct txx9_tmr_reg __iomem *tmrptr;
141
142 tmrptr = ioremap(baseaddr, sizeof(struct txx9_tmr_reg));
143 txx9tmr_stop_and_clear(tmrptr);
144 __raw_writel(TIMER_CCD, &tmrptr->ccdr);
145 __raw_writel(0, &tmrptr->itmr);
146 txx9_tmrptr = tmrptr;
147
148 clockevent_set_clock(cd, TIMER_CLK(imbusclk));
149 cd->max_delta_ns =
150 clockevent_delta2ns(0xffffffff >> (32 - TXX9_TIMER_BITS), cd);
151 cd->min_delta_ns = clockevent_delta2ns(0xf, cd);
152 cd->irq = irq;
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
159void __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 __raw_writel(TXx9_TMTCR_CRE, &tmrptr->tcr);
165 __raw_writel(0, &tmrptr->tisr);
166 __raw_writel(0xffffffff, &tmrptr->cpra);
167 __raw_writel(0, &tmrptr->itmr);
168 __raw_writel(0, &tmrptr->ccdr);
169 __raw_writel(0, &tmrptr->pgmr);
170 iounmap(tmrptr);
171}