1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * Copyright (C) 2018 Socionext Inc. |
4 | */ |
5 | |
6 | #include <linux/clk.h> |
7 | #include <linux/interrupt.h> |
8 | #include <linux/irq.h> |
9 | #include <linux/irqreturn.h> |
10 | #include <linux/sched_clock.h> |
11 | #include "timer-of.h" |
12 | |
13 | #define MLB_TMR_TMCSR_OFS 0x0 |
14 | #define MLB_TMR_TMR_OFS 0x4 |
15 | #define MLB_TMR_TMRLR1_OFS 0x8 |
16 | #define MLB_TMR_TMRLR2_OFS 0xc |
17 | #define MLB_TMR_REGSZPCH 0x10 |
18 | |
19 | #define MLB_TMR_TMCSR_OUTL BIT(5) |
20 | #define MLB_TMR_TMCSR_RELD BIT(4) |
21 | #define MLB_TMR_TMCSR_INTE BIT(3) |
22 | #define MLB_TMR_TMCSR_UF BIT(2) |
23 | #define MLB_TMR_TMCSR_CNTE BIT(1) |
24 | #define MLB_TMR_TMCSR_TRG BIT(0) |
25 | |
26 | #define MLB_TMR_TMCSR_CSL_DIV2 0 |
27 | #define MLB_TMR_DIV_CNT 2 |
28 | |
29 | #define MLB_TMR_SRC_CH 1 |
30 | #define MLB_TMR_EVT_CH 0 |
31 | |
32 | #define MLB_TMR_SRC_CH_OFS (MLB_TMR_REGSZPCH * MLB_TMR_SRC_CH) |
33 | #define MLB_TMR_EVT_CH_OFS (MLB_TMR_REGSZPCH * MLB_TMR_EVT_CH) |
34 | |
35 | #define MLB_TMR_SRC_TMCSR_OFS (MLB_TMR_SRC_CH_OFS + MLB_TMR_TMCSR_OFS) |
36 | #define MLB_TMR_SRC_TMR_OFS (MLB_TMR_SRC_CH_OFS + MLB_TMR_TMR_OFS) |
37 | #define MLB_TMR_SRC_TMRLR1_OFS (MLB_TMR_SRC_CH_OFS + MLB_TMR_TMRLR1_OFS) |
38 | #define MLB_TMR_SRC_TMRLR2_OFS (MLB_TMR_SRC_CH_OFS + MLB_TMR_TMRLR2_OFS) |
39 | |
40 | #define MLB_TMR_EVT_TMCSR_OFS (MLB_TMR_EVT_CH_OFS + MLB_TMR_TMCSR_OFS) |
41 | #define MLB_TMR_EVT_TMR_OFS (MLB_TMR_EVT_CH_OFS + MLB_TMR_TMR_OFS) |
42 | #define MLB_TMR_EVT_TMRLR1_OFS (MLB_TMR_EVT_CH_OFS + MLB_TMR_TMRLR1_OFS) |
43 | #define MLB_TMR_EVT_TMRLR2_OFS (MLB_TMR_EVT_CH_OFS + MLB_TMR_TMRLR2_OFS) |
44 | |
45 | #define MLB_TIMER_RATING 500 |
46 | #define MLB_TIMER_ONESHOT 0 |
47 | #define MLB_TIMER_PERIODIC 1 |
48 | |
49 | static irqreturn_t mlb_timer_interrupt(int irq, void *dev_id) |
50 | { |
51 | struct clock_event_device *clk = dev_id; |
52 | struct timer_of *to = to_timer_of(clkevt: clk); |
53 | u32 val; |
54 | |
55 | val = readl_relaxed(timer_of_base(to) + MLB_TMR_EVT_TMCSR_OFS); |
56 | val &= ~MLB_TMR_TMCSR_UF; |
57 | writel_relaxed(val, timer_of_base(to) + MLB_TMR_EVT_TMCSR_OFS); |
58 | |
59 | clk->event_handler(clk); |
60 | |
61 | return IRQ_HANDLED; |
62 | } |
63 | |
64 | static void mlb_evt_timer_start(struct timer_of *to, bool periodic) |
65 | { |
66 | u32 val = MLB_TMR_TMCSR_CSL_DIV2; |
67 | |
68 | val |= MLB_TMR_TMCSR_CNTE | MLB_TMR_TMCSR_TRG | MLB_TMR_TMCSR_INTE; |
69 | if (periodic) |
70 | val |= MLB_TMR_TMCSR_RELD; |
71 | writel_relaxed(val, timer_of_base(to) + MLB_TMR_EVT_TMCSR_OFS); |
72 | } |
73 | |
74 | static void mlb_evt_timer_stop(struct timer_of *to) |
75 | { |
76 | u32 val = readl_relaxed(timer_of_base(to) + MLB_TMR_EVT_TMCSR_OFS); |
77 | |
78 | val &= ~MLB_TMR_TMCSR_CNTE; |
79 | writel_relaxed(val, timer_of_base(to) + MLB_TMR_EVT_TMCSR_OFS); |
80 | } |
81 | |
82 | static void mlb_evt_timer_register_count(struct timer_of *to, unsigned long cnt) |
83 | { |
84 | writel_relaxed(cnt, timer_of_base(to) + MLB_TMR_EVT_TMRLR1_OFS); |
85 | } |
86 | |
87 | static int mlb_set_state_periodic(struct clock_event_device *clk) |
88 | { |
89 | struct timer_of *to = to_timer_of(clkevt: clk); |
90 | |
91 | mlb_evt_timer_stop(to); |
92 | mlb_evt_timer_register_count(to, cnt: to->of_clk.period); |
93 | mlb_evt_timer_start(to, MLB_TIMER_PERIODIC); |
94 | return 0; |
95 | } |
96 | |
97 | static int mlb_set_state_oneshot(struct clock_event_device *clk) |
98 | { |
99 | struct timer_of *to = to_timer_of(clkevt: clk); |
100 | |
101 | mlb_evt_timer_stop(to); |
102 | mlb_evt_timer_start(to, MLB_TIMER_ONESHOT); |
103 | return 0; |
104 | } |
105 | |
106 | static int mlb_set_state_shutdown(struct clock_event_device *clk) |
107 | { |
108 | struct timer_of *to = to_timer_of(clkevt: clk); |
109 | |
110 | mlb_evt_timer_stop(to); |
111 | return 0; |
112 | } |
113 | |
114 | static int mlb_clkevt_next_event(unsigned long event, |
115 | struct clock_event_device *clk) |
116 | { |
117 | struct timer_of *to = to_timer_of(clkevt: clk); |
118 | |
119 | mlb_evt_timer_stop(to); |
120 | mlb_evt_timer_register_count(to, cnt: event); |
121 | mlb_evt_timer_start(to, MLB_TIMER_ONESHOT); |
122 | return 0; |
123 | } |
124 | |
125 | static int mlb_config_clock_source(struct timer_of *to) |
126 | { |
127 | u32 val = MLB_TMR_TMCSR_CSL_DIV2; |
128 | |
129 | writel_relaxed(val, timer_of_base(to) + MLB_TMR_SRC_TMCSR_OFS); |
130 | writel_relaxed(~0, timer_of_base(to) + MLB_TMR_SRC_TMRLR1_OFS); |
131 | writel_relaxed(~0, timer_of_base(to) + MLB_TMR_SRC_TMRLR2_OFS); |
132 | val |= MLB_TMR_TMCSR_RELD | MLB_TMR_TMCSR_CNTE | MLB_TMR_TMCSR_TRG; |
133 | writel_relaxed(val, timer_of_base(to) + MLB_TMR_SRC_TMCSR_OFS); |
134 | return 0; |
135 | } |
136 | |
137 | static int mlb_config_clock_event(struct timer_of *to) |
138 | { |
139 | writel_relaxed(0, timer_of_base(to) + MLB_TMR_EVT_TMCSR_OFS); |
140 | return 0; |
141 | } |
142 | |
143 | static struct timer_of to = { |
144 | .flags = TIMER_OF_IRQ | TIMER_OF_BASE | TIMER_OF_CLOCK, |
145 | |
146 | .clkevt = { |
147 | .name = "mlb-clkevt" , |
148 | .rating = MLB_TIMER_RATING, |
149 | .cpumask = cpu_possible_mask, |
150 | .features = CLOCK_EVT_FEAT_DYNIRQ | CLOCK_EVT_FEAT_ONESHOT, |
151 | .set_state_oneshot = mlb_set_state_oneshot, |
152 | .set_state_periodic = mlb_set_state_periodic, |
153 | .set_state_shutdown = mlb_set_state_shutdown, |
154 | .set_next_event = mlb_clkevt_next_event, |
155 | }, |
156 | |
157 | .of_irq = { |
158 | .flags = IRQF_TIMER | IRQF_IRQPOLL, |
159 | .handler = mlb_timer_interrupt, |
160 | }, |
161 | }; |
162 | |
163 | static u64 notrace mlb_timer_sched_read(void) |
164 | { |
165 | return ~readl_relaxed(timer_of_base(&to) + MLB_TMR_SRC_TMR_OFS); |
166 | } |
167 | |
168 | static int __init mlb_timer_init(struct device_node *node) |
169 | { |
170 | int ret; |
171 | unsigned long rate; |
172 | |
173 | ret = timer_of_init(np: node, to: &to); |
174 | if (ret) |
175 | return ret; |
176 | |
177 | rate = timer_of_rate(to: &to) / MLB_TMR_DIV_CNT; |
178 | mlb_config_clock_source(to: &to); |
179 | clocksource_mmio_init(timer_of_base(to: &to) + MLB_TMR_SRC_TMR_OFS, |
180 | node->name, rate, MLB_TIMER_RATING, 32, |
181 | clocksource_mmio_readl_down); |
182 | sched_clock_register(read: mlb_timer_sched_read, bits: 32, rate); |
183 | mlb_config_clock_event(to: &to); |
184 | clockevents_config_and_register(dev: &to.clkevt, freq: timer_of_rate(to: &to), min_delta: 15, |
185 | max_delta: 0xffffffff); |
186 | return 0; |
187 | } |
188 | TIMER_OF_DECLARE(mlb_peritimer, "socionext,milbeaut-timer" , |
189 | mlb_timer_init); |
190 | |