projects/linux·blob v4.16 · refs

159 lines · 3.6 KiB

1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2017 Spreadtrum Communications Inc.
4 */
5
6#include <linux/init.h>
7#include <linux/interrupt.h>
8
9#include "timer-of.h"
10
11#define TIMER_NAME "sprd_timer"
12
13#define TIMER_LOAD_LO 0x0
14#define TIMER_LOAD_HI 0x4
15#define TIMER_VALUE_LO 0x8
16#define TIMER_VALUE_HI 0xc
17
18#define TIMER_CTL 0x10
19#define TIMER_CTL_PERIOD_MODE BIT(0)
20#define TIMER_CTL_ENABLE BIT(1)
21#define TIMER_CTL_64BIT_WIDTH BIT(16)
22
23#define TIMER_INT 0x14
24#define TIMER_INT_EN BIT(0)
25#define TIMER_INT_RAW_STS BIT(1)
26#define TIMER_INT_MASK_STS BIT(2)
27#define TIMER_INT_CLR BIT(3)
28
29#define TIMER_VALUE_SHDW_LO 0x18
30#define TIMER_VALUE_SHDW_HI 0x1c
31
32#define TIMER_VALUE_LO_MASK GENMASK(31, 0)
33
34static void sprd_timer_enable(void __iomem *base, u32 flag)
35{
36 u32 val = readl_relaxed(base + TIMER_CTL);
37
38 val |= TIMER_CTL_ENABLE;
39 if (flag & TIMER_CTL_64BIT_WIDTH)
40 val |= TIMER_CTL_64BIT_WIDTH;
41 else
42 val &= ~TIMER_CTL_64BIT_WIDTH;
43
44 if (flag & TIMER_CTL_PERIOD_MODE)
45 val |= TIMER_CTL_PERIOD_MODE;
46 else
47 val &= ~TIMER_CTL_PERIOD_MODE;
48
49 writel_relaxed(val, base + TIMER_CTL);
50}
51
52static void sprd_timer_disable(void __iomem *base)
53{
54 u32 val = readl_relaxed(base + TIMER_CTL);
55
56 val &= ~TIMER_CTL_ENABLE;
57 writel_relaxed(val, base + TIMER_CTL);
58}
59
60static void sprd_timer_update_counter(void __iomem *base, unsigned long cycles)
61{
62 writel_relaxed(cycles & TIMER_VALUE_LO_MASK, base + TIMER_LOAD_LO);
63 writel_relaxed(0, base + TIMER_LOAD_HI);
64}
65
66static void sprd_timer_enable_interrupt(void __iomem *base)
67{
68 writel_relaxed(TIMER_INT_EN, base + TIMER_INT);
69}
70
71static void sprd_timer_clear_interrupt(void __iomem *base)
72{
73 u32 val = readl_relaxed(base + TIMER_INT);
74
75 val |= TIMER_INT_CLR;
76 writel_relaxed(val, base + TIMER_INT);
77}
78
79static int sprd_timer_set_next_event(unsigned long cycles,
80 struct clock_event_device *ce)
81{
82 struct timer_of *to = to_timer_of(ce);
83
84 sprd_timer_disable(timer_of_base(to));
85 sprd_timer_update_counter(timer_of_base(to), cycles);
86 sprd_timer_enable(timer_of_base(to), 0);
87
88 return 0;
89}
90
91static int sprd_timer_set_periodic(struct clock_event_device *ce)
92{
93 struct timer_of *to = to_timer_of(ce);
94
95 sprd_timer_disable(timer_of_base(to));
96 sprd_timer_update_counter(timer_of_base(to), timer_of_period(to));
97 sprd_timer_enable(timer_of_base(to), TIMER_CTL_PERIOD_MODE);
98
99 return 0;
100}
101
102static int sprd_timer_shutdown(struct clock_event_device *ce)
103{
104 struct timer_of *to = to_timer_of(ce);
105
106 sprd_timer_disable(timer_of_base(to));
107 return 0;
108}
109
110static irqreturn_t sprd_timer_interrupt(int irq, void *dev_id)
111{
112 struct clock_event_device *ce = (struct clock_event_device *)dev_id;
113 struct timer_of *to = to_timer_of(ce);
114
115 sprd_timer_clear_interrupt(timer_of_base(to));
116
117 if (clockevent_state_oneshot(ce))
118 sprd_timer_disable(timer_of_base(to));
119
120 ce->event_handler(ce);
121 return IRQ_HANDLED;
122}
123
124static struct timer_of to = {
125 .flags = TIMER_OF_IRQ | TIMER_OF_BASE | TIMER_OF_CLOCK,
126
127 .clkevt = {
128 .name = TIMER_NAME,
129 .rating = 300,
130 .features = CLOCK_EVT_FEAT_DYNIRQ | CLOCK_EVT_FEAT_PERIODIC |
131 CLOCK_EVT_FEAT_ONESHOT,
132 .set_state_shutdown = sprd_timer_shutdown,
133 .set_state_periodic = sprd_timer_set_periodic,
134 .set_next_event = sprd_timer_set_next_event,
135 .cpumask = cpu_possible_mask,
136 },
137
138 .of_irq = {
139 .handler = sprd_timer_interrupt,
140 .flags = IRQF_TIMER | IRQF_IRQPOLL,
141 },
142};
143
144static int __init sprd_timer_init(struct device_node *np)
145{
146 int ret;
147
148 ret = timer_of_init(np, &to);
149 if (ret)
150 return ret;
151
152 sprd_timer_enable_interrupt(timer_of_base(&to));
153 clockevents_config_and_register(&to.clkevt, timer_of_rate(&to),
154 1, UINT_MAX);
155
156 return 0;
157}
158
159TIMER_OF_DECLARE(sc9860_timer, "sprd,sc9860-timer", sprd_timer_init);