1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211
|
/*
* Rockchip timer support
*
* Copyright (C) Daniel Lezcano <daniel.lezcano@linaro.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/clk.h>
#include <linux/clockchips.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#define TIMER_NAME "rk_timer"
#define TIMER_LOAD_COUNT0 0x00
#define TIMER_LOAD_COUNT1 0x04
#define TIMER_CONTROL_REG3288 0x10
#define TIMER_CONTROL_REG3399 0x1c
#define TIMER_INT_STATUS 0x18
#define TIMER_DISABLE 0x0
#define TIMER_ENABLE 0x1
#define TIMER_MODE_FREE_RUNNING (0 << 1)
#define TIMER_MODE_USER_DEFINED_COUNT (1 << 1)
#define TIMER_INT_UNMASK (1 << 2)
struct bc_timer {
struct clock_event_device ce;
void __iomem *base;
void __iomem *ctrl;
u32 freq;
};
static struct bc_timer bc_timer;
static inline struct bc_timer *rk_timer(struct clock_event_device *ce)
{
return container_of(ce, struct bc_timer, ce);
}
static inline void __iomem *rk_base(struct clock_event_device *ce)
{
return rk_timer(ce)->base;
}
static inline void __iomem *rk_ctrl(struct clock_event_device *ce)
{
return rk_timer(ce)->ctrl;
}
static inline void rk_timer_disable(struct clock_event_device *ce)
{
writel_relaxed(TIMER_DISABLE, rk_ctrl(ce));
}
static inline void rk_timer_enable(struct clock_event_device *ce, u32 flags)
{
writel_relaxed(TIMER_ENABLE | TIMER_INT_UNMASK | flags,
rk_ctrl(ce));
}
static void rk_timer_update_counter(unsigned long cycles,
struct clock_event_device *ce)
{
writel_relaxed(cycles, rk_base(ce) + TIMER_LOAD_COUNT0);
writel_relaxed(0, rk_base(ce) + TIMER_LOAD_COUNT1);
}
static void rk_timer_interrupt_clear(struct clock_event_device *ce)
{
writel_relaxed(1, rk_base(ce) + TIMER_INT_STATUS);
}
static inline int rk_timer_set_next_event(unsigned long cycles,
struct clock_event_device *ce)
{
rk_timer_disable(ce);
rk_timer_update_counter(cycles, ce);
rk_timer_enable(ce, TIMER_MODE_USER_DEFINED_COUNT);
return 0;
}
static int rk_timer_shutdown(struct clock_event_device *ce)
{
rk_timer_disable(ce);
return 0;
}
static int rk_timer_set_periodic(struct clock_event_device *ce)
{
rk_timer_disable(ce);
rk_timer_update_counter(rk_timer(ce)->freq / HZ - 1, ce);
rk_timer_enable(ce, TIMER_MODE_FREE_RUNNING);
return 0;
}
static irqreturn_t rk_timer_interrupt(int irq, void *dev_id)
{
struct clock_event_device *ce = dev_id;
rk_timer_interrupt_clear(ce);
if (clockevent_state_oneshot(ce))
rk_timer_disable(ce);
ce->event_handler(ce);
return IRQ_HANDLED;
}
static int __init rk_timer_init(struct device_node *np, u32 ctrl_reg)
{
struct clock_event_device *ce = &bc_timer.ce;
struct clk *timer_clk;
struct clk *pclk;
int ret = -EINVAL, irq;
bc_timer.base = of_iomap(np, 0);
if (!bc_timer.base) {
pr_err("Failed to get base address for '%s'\n", TIMER_NAME);
return -ENXIO;
}
bc_timer.ctrl = bc_timer.base + ctrl_reg;
pclk = of_clk_get_by_name(np, "pclk");
if (IS_ERR(pclk)) {
ret = PTR_ERR(pclk);
pr_err("Failed to get pclk for '%s'\n", TIMER_NAME);
goto out_unmap;
}
ret = clk_prepare_enable(pclk);
if (ret) {
pr_err("Failed to enable pclk for '%s'\n", TIMER_NAME);
goto out_unmap;
}
timer_clk = of_clk_get_by_name(np, "timer");
if (IS_ERR(timer_clk)) {
ret = PTR_ERR(timer_clk);
pr_err("Failed to get timer clock for '%s'\n", TIMER_NAME);
goto out_timer_clk;
}
ret = clk_prepare_enable(timer_clk);
if (ret) {
pr_err("Failed to enable timer clock\n");
goto out_timer_clk;
}
bc_timer.freq = clk_get_rate(timer_clk);
irq = irq_of_parse_and_map(np, 0);
if (!irq) {
ret = -EINVAL;
pr_err("Failed to map interrupts for '%s'\n", TIMER_NAME);
goto out_irq;
}
ce->name = TIMER_NAME;
ce->features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT |
CLOCK_EVT_FEAT_DYNIRQ;
ce->set_next_event = rk_timer_set_next_event;
ce->set_state_shutdown = rk_timer_shutdown;
ce->set_state_periodic = rk_timer_set_periodic;
ce->irq = irq;
ce->cpumask = cpu_possible_mask;
ce->rating = 250;
rk_timer_interrupt_clear(ce);
rk_timer_disable(ce);
ret = request_irq(irq, rk_timer_interrupt, IRQF_TIMER, TIMER_NAME, ce);
if (ret) {
pr_err("Failed to initialize '%s': %d\n", TIMER_NAME, ret);
goto out_irq;
}
clockevents_config_and_register(ce, bc_timer.freq, 1, UINT_MAX);
return 0;
out_irq:
clk_disable_unprepare(timer_clk);
out_timer_clk:
clk_disable_unprepare(pclk);
out_unmap:
iounmap(bc_timer.base);
return ret;
}
static int __init rk3288_timer_init(struct device_node *np)
{
return rk_timer_init(np, TIMER_CONTROL_REG3288);
}
static int __init rk3399_timer_init(struct device_node *np)
{
return rk_timer_init(np, TIMER_CONTROL_REG3399);
}
CLOCKSOURCE_OF_DECLARE(rk3288_timer, "rockchip,rk3288-timer",
rk3288_timer_init);
CLOCKSOURCE_OF_DECLARE(rk3399_timer, "rockchip,rk3399-timer",
rk3399_timer_init);
|