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 #define TIMER_VALUE_HI_MASK GENMASK(31, 0)
34
sprd_timer_enable(void __iomem * base,u32 flag)35 static void sprd_timer_enable(void __iomem *base, u32 flag)
36 {
37 u32 val = readl_relaxed(base + TIMER_CTL);
38
39 val |= TIMER_CTL_ENABLE;
40 if (flag & TIMER_CTL_64BIT_WIDTH)
41 val |= TIMER_CTL_64BIT_WIDTH;
42 else
43 val &= ~TIMER_CTL_64BIT_WIDTH;
44
45 if (flag & TIMER_CTL_PERIOD_MODE)
46 val |= TIMER_CTL_PERIOD_MODE;
47 else
48 val &= ~TIMER_CTL_PERIOD_MODE;
49
50 writel_relaxed(val, base + TIMER_CTL);
51 }
52
sprd_timer_disable(void __iomem * base)53 static void sprd_timer_disable(void __iomem *base)
54 {
55 u32 val = readl_relaxed(base + TIMER_CTL);
56
57 val &= ~TIMER_CTL_ENABLE;
58 writel_relaxed(val, base + TIMER_CTL);
59 }
60
sprd_timer_update_counter(void __iomem * base,unsigned long cycles)61 static void sprd_timer_update_counter(void __iomem *base, unsigned long cycles)
62 {
63 writel_relaxed(cycles & TIMER_VALUE_LO_MASK, base + TIMER_LOAD_LO);
64 writel_relaxed(0, base + TIMER_LOAD_HI);
65 }
66
sprd_timer_enable_interrupt(void __iomem * base)67 static void sprd_timer_enable_interrupt(void __iomem *base)
68 {
69 writel_relaxed(TIMER_INT_EN, base + TIMER_INT);
70 }
71
sprd_timer_clear_interrupt(void __iomem * base)72 static void sprd_timer_clear_interrupt(void __iomem *base)
73 {
74 u32 val = readl_relaxed(base + TIMER_INT);
75
76 val |= TIMER_INT_CLR;
77 writel_relaxed(val, base + TIMER_INT);
78 }
79
sprd_timer_set_next_event(unsigned long cycles,struct clock_event_device * ce)80 static int sprd_timer_set_next_event(unsigned long cycles,
81 struct clock_event_device *ce)
82 {
83 struct timer_of *to = to_timer_of(ce);
84
85 sprd_timer_disable(timer_of_base(to));
86 sprd_timer_update_counter(timer_of_base(to), cycles);
87 sprd_timer_enable(timer_of_base(to), 0);
88
89 return 0;
90 }
91
sprd_timer_set_periodic(struct clock_event_device * ce)92 static int sprd_timer_set_periodic(struct clock_event_device *ce)
93 {
94 struct timer_of *to = to_timer_of(ce);
95
96 sprd_timer_disable(timer_of_base(to));
97 sprd_timer_update_counter(timer_of_base(to), timer_of_period(to));
98 sprd_timer_enable(timer_of_base(to), TIMER_CTL_PERIOD_MODE);
99
100 return 0;
101 }
102
sprd_timer_shutdown(struct clock_event_device * ce)103 static int sprd_timer_shutdown(struct clock_event_device *ce)
104 {
105 struct timer_of *to = to_timer_of(ce);
106
107 sprd_timer_disable(timer_of_base(to));
108 return 0;
109 }
110
sprd_timer_interrupt(int irq,void * dev_id)111 static irqreturn_t sprd_timer_interrupt(int irq, void *dev_id)
112 {
113 struct clock_event_device *ce = (struct clock_event_device *)dev_id;
114 struct timer_of *to = to_timer_of(ce);
115
116 sprd_timer_clear_interrupt(timer_of_base(to));
117
118 if (clockevent_state_oneshot(ce))
119 sprd_timer_disable(timer_of_base(to));
120
121 ce->event_handler(ce);
122 return IRQ_HANDLED;
123 }
124
125 static struct timer_of to = {
126 .flags = TIMER_OF_IRQ | TIMER_OF_BASE | TIMER_OF_CLOCK,
127
128 .clkevt = {
129 .name = TIMER_NAME,
130 .rating = 300,
131 .features = CLOCK_EVT_FEAT_DYNIRQ | CLOCK_EVT_FEAT_PERIODIC |
132 CLOCK_EVT_FEAT_ONESHOT,
133 .set_state_shutdown = sprd_timer_shutdown,
134 .set_state_periodic = sprd_timer_set_periodic,
135 .set_next_event = sprd_timer_set_next_event,
136 .cpumask = cpu_possible_mask,
137 },
138
139 .of_irq = {
140 .handler = sprd_timer_interrupt,
141 .flags = IRQF_TIMER | IRQF_IRQPOLL,
142 },
143 };
144
sprd_timer_init(struct device_node * np)145 static int __init sprd_timer_init(struct device_node *np)
146 {
147 int ret;
148
149 ret = timer_of_init(np, &to);
150 if (ret)
151 return ret;
152
153 sprd_timer_enable_interrupt(timer_of_base(&to));
154 clockevents_config_and_register(&to.clkevt, timer_of_rate(&to),
155 1, UINT_MAX);
156
157 return 0;
158 }
159
160 static struct timer_of suspend_to = {
161 .flags = TIMER_OF_BASE | TIMER_OF_CLOCK,
162 };
163
sprd_suspend_timer_read(struct clocksource * cs)164 static u64 sprd_suspend_timer_read(struct clocksource *cs)
165 {
166 u32 lo, hi;
167
168 do {
169 hi = readl_relaxed(timer_of_base(&suspend_to) +
170 TIMER_VALUE_SHDW_HI);
171 lo = readl_relaxed(timer_of_base(&suspend_to) +
172 TIMER_VALUE_SHDW_LO);
173 } while (hi != readl_relaxed(timer_of_base(&suspend_to) + TIMER_VALUE_SHDW_HI));
174
175 return ~(((u64)hi << 32) | lo);
176 }
177
sprd_suspend_timer_enable(struct clocksource * cs)178 static int sprd_suspend_timer_enable(struct clocksource *cs)
179 {
180 writel_relaxed(TIMER_VALUE_LO_MASK,
181 timer_of_base(&suspend_to) + TIMER_LOAD_LO);
182 writel_relaxed(TIMER_VALUE_HI_MASK,
183 timer_of_base(&suspend_to) + TIMER_LOAD_HI);
184 sprd_timer_enable(timer_of_base(&suspend_to),
185 TIMER_CTL_PERIOD_MODE|TIMER_CTL_64BIT_WIDTH);
186
187 return 0;
188 }
189
sprd_suspend_timer_disable(struct clocksource * cs)190 static void sprd_suspend_timer_disable(struct clocksource *cs)
191 {
192 sprd_timer_disable(timer_of_base(&suspend_to));
193 }
194
195 static struct clocksource suspend_clocksource = {
196 .name = "sprd_suspend_timer",
197 .rating = 200,
198 .read = sprd_suspend_timer_read,
199 .enable = sprd_suspend_timer_enable,
200 .disable = sprd_suspend_timer_disable,
201 .mask = CLOCKSOURCE_MASK(64),
202 .flags = CLOCK_SOURCE_IS_CONTINUOUS | CLOCK_SOURCE_SUSPEND_NONSTOP,
203 };
204
sprd_suspend_timer_init(struct device_node * np)205 static int __init sprd_suspend_timer_init(struct device_node *np)
206 {
207 int ret;
208
209 ret = timer_of_init(np, &suspend_to);
210 if (ret)
211 return ret;
212
213 clocksource_register_hz(&suspend_clocksource,
214 timer_of_rate(&suspend_to));
215
216 return 0;
217 }
218
219 TIMER_OF_DECLARE(sc9860_timer, "sprd,sc9860-timer", sprd_timer_init);
220 TIMER_OF_DECLARE(sc9860_persistent_timer, "sprd,sc9860-suspend-timer",
221 sprd_suspend_timer_init);
222