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  • only in /asuswrt-rt-n18u-9.0.0.4.380.2695/release/src-rt-6.x.4708/linux/linux-2.6.36/arch/mips/kernel/
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
23struct txx9_clocksource {
24	struct clocksource cs;
25	struct txx9_tmr_reg __iomem *tmrptr;
26};
27
28static cycle_t txx9_cs_read(struct clocksource *cs)
29{
30	struct txx9_clocksource *txx9_cs =
31		container_of(cs, struct txx9_clocksource, cs);
32	return __raw_readl(&txx9_cs->tmrptr->trr);
33}
34
35/* Use 1 bit smaller width to use full bits in that width */
36#define TXX9_CLOCKSOURCE_BITS (TXX9_TIMER_BITS - 1)
37
38static struct txx9_clocksource txx9_clocksource = {
39	.cs = {
40		.name		= "TXx9",
41		.rating		= 200,
42		.read		= txx9_cs_read,
43		.mask		= CLOCKSOURCE_MASK(TXX9_CLOCKSOURCE_BITS),
44		.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
45	},
46};
47
48void __init txx9_clocksource_init(unsigned long baseaddr,
49				  unsigned int imbusclk)
50{
51	struct txx9_tmr_reg __iomem *tmrptr;
52
53	clocksource_set_clock(&txx9_clocksource.cs, TIMER_CLK(imbusclk));
54	clocksource_register(&txx9_clocksource.cs);
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
66struct txx9_clock_event_device {
67	struct clock_event_device cd;
68	struct txx9_tmr_reg __iomem *tmrptr;
69};
70
71static 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
79static 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
111static 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
125static 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
136static 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
147static struct irqaction txx9tmr_irq = {
148	.handler	= txx9tmr_interrupt,
149	.flags		= IRQF_DISABLED | IRQF_PERCPU | IRQF_TIMER,
150	.name		= "txx9tmr",
151	.dev_id		= &txx9_clock_event_device,
152};
153
154void __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
178void __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