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
sprd_timer_enable(void __iomem * base,u32 flag)34 static 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
sprd_timer_disable(void __iomem * base)52 static 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
sprd_timer_update_counter(void __iomem * base,unsigned long cycles)60 static 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
sprd_timer_enable_interrupt(void __iomem * base)66 static void sprd_timer_enable_interrupt(void __iomem *base)
67 {
68 writel_relaxed(TIMER_INT_EN, base + TIMER_INT);
69 }
70
sprd_timer_clear_interrupt(void __iomem * base)71 static 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
sprd_timer_set_next_event(unsigned long cycles,struct clock_event_device * ce)79 static 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
sprd_timer_set_periodic(struct clock_event_device * ce)91 static 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
sprd_timer_shutdown(struct clock_event_device * ce)102 static 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
sprd_timer_interrupt(int irq,void * dev_id)110 static 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
124 static 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
sprd_timer_init(struct device_node * np)144 static 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
159 static struct timer_of suspend_to = {
160 .flags = TIMER_OF_BASE | TIMER_OF_CLOCK,
161 };
162
sprd_suspend_timer_read(struct clocksource * cs)163 static u64 sprd_suspend_timer_read(struct clocksource *cs)
164 {
165 return ~(u64)readl_relaxed(timer_of_base(&suspend_to) +
166 TIMER_VALUE_SHDW_LO) & cs->mask;
167 }
168
sprd_suspend_timer_enable(struct clocksource * cs)169 static int sprd_suspend_timer_enable(struct clocksource *cs)
170 {
171 sprd_timer_update_counter(timer_of_base(&suspend_to),
172 TIMER_VALUE_LO_MASK);
173 sprd_timer_enable(timer_of_base(&suspend_to), TIMER_CTL_PERIOD_MODE);
174
175 return 0;
176 }
177
sprd_suspend_timer_disable(struct clocksource * cs)178 static void sprd_suspend_timer_disable(struct clocksource *cs)
179 {
180 sprd_timer_disable(timer_of_base(&suspend_to));
181 }
182
183 static struct clocksource suspend_clocksource = {
184 .name = "sprd_suspend_timer",
185 .rating = 200,
186 .read = sprd_suspend_timer_read,
187 .enable = sprd_suspend_timer_enable,
188 .disable = sprd_suspend_timer_disable,
189 .mask = CLOCKSOURCE_MASK(32),
190 .flags = CLOCK_SOURCE_IS_CONTINUOUS | CLOCK_SOURCE_SUSPEND_NONSTOP,
191 };
192
sprd_suspend_timer_init(struct device_node * np)193 static int __init sprd_suspend_timer_init(struct device_node *np)
194 {
195 int ret;
196
197 ret = timer_of_init(np, &suspend_to);
198 if (ret)
199 return ret;
200
201 clocksource_register_hz(&suspend_clocksource,
202 timer_of_rate(&suspend_to));
203
204 return 0;
205 }
206
207 TIMER_OF_DECLARE(sc9860_timer, "sprd,sc9860-timer", sprd_timer_init);
208 TIMER_OF_DECLARE(sc9860_persistent_timer, "sprd,sc9860-suspend-timer",
209 sprd_suspend_timer_init);
210