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v6.8
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * Actions Semi Owl timer
  4 *
  5 * Copyright 2012 Actions Semi Inc.
  6 * Author: Actions Semi, Inc.
  7 *
  8 * Copyright (c) 2017 SUSE Linux GmbH
  9 * Author: Andreas Färber
 10 */
 11
 12#include <linux/clk.h>
 13#include <linux/clockchips.h>
 14#include <linux/interrupt.h>
 15#include <linux/irq.h>
 16#include <linux/irqreturn.h>
 17#include <linux/sched_clock.h>
 18#include <linux/of.h>
 19#include <linux/of_address.h>
 20#include <linux/of_irq.h>
 21
 22#define OWL_Tx_CTL		0x0
 23#define OWL_Tx_CMP		0x4
 24#define OWL_Tx_VAL		0x8
 25
 26#define OWL_Tx_CTL_PD		BIT(0)
 27#define OWL_Tx_CTL_INTEN	BIT(1)
 28#define OWL_Tx_CTL_EN		BIT(2)
 29
 30static void __iomem *owl_timer_base;
 31static void __iomem *owl_clksrc_base;
 32static void __iomem *owl_clkevt_base;
 33
 34static inline void owl_timer_reset(void __iomem *base)
 35{
 36	writel(0, base + OWL_Tx_CTL);
 37	writel(0, base + OWL_Tx_VAL);
 38	writel(0, base + OWL_Tx_CMP);
 39}
 40
 41static inline void owl_timer_set_enabled(void __iomem *base, bool enabled)
 42{
 43	u32 ctl = readl(base + OWL_Tx_CTL);
 44
 45	/* PD bit is cleared when set */
 46	ctl &= ~OWL_Tx_CTL_PD;
 47
 48	if (enabled)
 49		ctl |= OWL_Tx_CTL_EN;
 50	else
 51		ctl &= ~OWL_Tx_CTL_EN;
 52
 53	writel(ctl, base + OWL_Tx_CTL);
 54}
 55
 56static u64 notrace owl_timer_sched_read(void)
 57{
 58	return (u64)readl(owl_clksrc_base + OWL_Tx_VAL);
 59}
 60
 61static int owl_timer_set_state_shutdown(struct clock_event_device *evt)
 62{
 63	owl_timer_set_enabled(owl_clkevt_base, false);
 64
 65	return 0;
 66}
 67
 68static int owl_timer_set_state_oneshot(struct clock_event_device *evt)
 69{
 70	owl_timer_reset(owl_clkevt_base);
 71
 72	return 0;
 73}
 74
 75static int owl_timer_tick_resume(struct clock_event_device *evt)
 76{
 77	return 0;
 78}
 79
 80static int owl_timer_set_next_event(unsigned long evt,
 81				    struct clock_event_device *ev)
 82{
 83	void __iomem *base = owl_clkevt_base;
 84
 85	owl_timer_set_enabled(base, false);
 86	writel(OWL_Tx_CTL_INTEN, base + OWL_Tx_CTL);
 87	writel(0, base + OWL_Tx_VAL);
 88	writel(evt, base + OWL_Tx_CMP);
 89	owl_timer_set_enabled(base, true);
 90
 91	return 0;
 92}
 93
 94static struct clock_event_device owl_clockevent = {
 95	.name			= "owl_tick",
 96	.rating			= 200,
 97	.features		= CLOCK_EVT_FEAT_ONESHOT |
 98				  CLOCK_EVT_FEAT_DYNIRQ,
 99	.set_state_shutdown	= owl_timer_set_state_shutdown,
100	.set_state_oneshot	= owl_timer_set_state_oneshot,
101	.tick_resume		= owl_timer_tick_resume,
102	.set_next_event		= owl_timer_set_next_event,
103};
104
105static irqreturn_t owl_timer1_interrupt(int irq, void *dev_id)
106{
107	struct clock_event_device *evt = (struct clock_event_device *)dev_id;
108
109	writel(OWL_Tx_CTL_PD, owl_clkevt_base + OWL_Tx_CTL);
110
111	evt->event_handler(evt);
112
113	return IRQ_HANDLED;
114}
115
116static int __init owl_timer_init(struct device_node *node)
117{
118	struct clk *clk;
119	unsigned long rate;
120	int timer1_irq, ret;
121
122	owl_timer_base = of_io_request_and_map(node, 0, "owl-timer");
123	if (IS_ERR(owl_timer_base)) {
124		pr_err("Can't map timer registers\n");
125		return PTR_ERR(owl_timer_base);
126	}
127
128	owl_clksrc_base = owl_timer_base + 0x08;
129	owl_clkevt_base = owl_timer_base + 0x14;
130
131	timer1_irq = of_irq_get_byname(node, "timer1");
132	if (timer1_irq <= 0) {
133		pr_err("Can't parse timer1 IRQ\n");
134		return -EINVAL;
135	}
136
137	clk = of_clk_get(node, 0);
138	if (IS_ERR(clk)) {
139		ret = PTR_ERR(clk);
140		pr_err("Failed to get clock for clocksource (%d)\n", ret);
141		return ret;
142	}
143
144	rate = clk_get_rate(clk);
145
146	owl_timer_reset(owl_clksrc_base);
147	owl_timer_set_enabled(owl_clksrc_base, true);
148
149	sched_clock_register(owl_timer_sched_read, 32, rate);
150	ret = clocksource_mmio_init(owl_clksrc_base + OWL_Tx_VAL, node->name,
151				    rate, 200, 32, clocksource_mmio_readl_up);
152	if (ret) {
153		pr_err("Failed to register clocksource (%d)\n", ret);
154		return ret;
155	}
156
157	owl_timer_reset(owl_clkevt_base);
158
159	ret = request_irq(timer1_irq, owl_timer1_interrupt, IRQF_TIMER,
160			  "owl-timer", &owl_clockevent);
161	if (ret) {
162		pr_err("failed to request irq %d\n", timer1_irq);
163		return ret;
164	}
165
166	owl_clockevent.cpumask = cpumask_of(0);
167	owl_clockevent.irq = timer1_irq;
168
169	clockevents_config_and_register(&owl_clockevent, rate,
170					0xf, 0xffffffff);
171
172	return 0;
173}
174TIMER_OF_DECLARE(owl_s500, "actions,s500-timer", owl_timer_init);
175TIMER_OF_DECLARE(owl_s700, "actions,s700-timer", owl_timer_init);
176TIMER_OF_DECLARE(owl_s900, "actions,s900-timer", owl_timer_init);
v5.14.15
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * Actions Semi Owl timer
  4 *
  5 * Copyright 2012 Actions Semi Inc.
  6 * Author: Actions Semi, Inc.
  7 *
  8 * Copyright (c) 2017 SUSE Linux GmbH
  9 * Author: Andreas Färber
 10 */
 11
 12#include <linux/clk.h>
 13#include <linux/clockchips.h>
 14#include <linux/interrupt.h>
 15#include <linux/irq.h>
 16#include <linux/irqreturn.h>
 17#include <linux/sched_clock.h>
 18#include <linux/of.h>
 19#include <linux/of_address.h>
 20#include <linux/of_irq.h>
 21
 22#define OWL_Tx_CTL		0x0
 23#define OWL_Tx_CMP		0x4
 24#define OWL_Tx_VAL		0x8
 25
 26#define OWL_Tx_CTL_PD		BIT(0)
 27#define OWL_Tx_CTL_INTEN	BIT(1)
 28#define OWL_Tx_CTL_EN		BIT(2)
 29
 30static void __iomem *owl_timer_base;
 31static void __iomem *owl_clksrc_base;
 32static void __iomem *owl_clkevt_base;
 33
 34static inline void owl_timer_reset(void __iomem *base)
 35{
 36	writel(0, base + OWL_Tx_CTL);
 37	writel(0, base + OWL_Tx_VAL);
 38	writel(0, base + OWL_Tx_CMP);
 39}
 40
 41static inline void owl_timer_set_enabled(void __iomem *base, bool enabled)
 42{
 43	u32 ctl = readl(base + OWL_Tx_CTL);
 44
 45	/* PD bit is cleared when set */
 46	ctl &= ~OWL_Tx_CTL_PD;
 47
 48	if (enabled)
 49		ctl |= OWL_Tx_CTL_EN;
 50	else
 51		ctl &= ~OWL_Tx_CTL_EN;
 52
 53	writel(ctl, base + OWL_Tx_CTL);
 54}
 55
 56static u64 notrace owl_timer_sched_read(void)
 57{
 58	return (u64)readl(owl_clksrc_base + OWL_Tx_VAL);
 59}
 60
 61static int owl_timer_set_state_shutdown(struct clock_event_device *evt)
 62{
 63	owl_timer_set_enabled(owl_clkevt_base, false);
 64
 65	return 0;
 66}
 67
 68static int owl_timer_set_state_oneshot(struct clock_event_device *evt)
 69{
 70	owl_timer_reset(owl_clkevt_base);
 71
 72	return 0;
 73}
 74
 75static int owl_timer_tick_resume(struct clock_event_device *evt)
 76{
 77	return 0;
 78}
 79
 80static int owl_timer_set_next_event(unsigned long evt,
 81				    struct clock_event_device *ev)
 82{
 83	void __iomem *base = owl_clkevt_base;
 84
 85	owl_timer_set_enabled(base, false);
 86	writel(OWL_Tx_CTL_INTEN, base + OWL_Tx_CTL);
 87	writel(0, base + OWL_Tx_VAL);
 88	writel(evt, base + OWL_Tx_CMP);
 89	owl_timer_set_enabled(base, true);
 90
 91	return 0;
 92}
 93
 94static struct clock_event_device owl_clockevent = {
 95	.name			= "owl_tick",
 96	.rating			= 200,
 97	.features		= CLOCK_EVT_FEAT_ONESHOT |
 98				  CLOCK_EVT_FEAT_DYNIRQ,
 99	.set_state_shutdown	= owl_timer_set_state_shutdown,
100	.set_state_oneshot	= owl_timer_set_state_oneshot,
101	.tick_resume		= owl_timer_tick_resume,
102	.set_next_event		= owl_timer_set_next_event,
103};
104
105static irqreturn_t owl_timer1_interrupt(int irq, void *dev_id)
106{
107	struct clock_event_device *evt = (struct clock_event_device *)dev_id;
108
109	writel(OWL_Tx_CTL_PD, owl_clkevt_base + OWL_Tx_CTL);
110
111	evt->event_handler(evt);
112
113	return IRQ_HANDLED;
114}
115
116static int __init owl_timer_init(struct device_node *node)
117{
118	struct clk *clk;
119	unsigned long rate;
120	int timer1_irq, ret;
121
122	owl_timer_base = of_io_request_and_map(node, 0, "owl-timer");
123	if (IS_ERR(owl_timer_base)) {
124		pr_err("Can't map timer registers\n");
125		return PTR_ERR(owl_timer_base);
126	}
127
128	owl_clksrc_base = owl_timer_base + 0x08;
129	owl_clkevt_base = owl_timer_base + 0x14;
130
131	timer1_irq = of_irq_get_byname(node, "timer1");
132	if (timer1_irq <= 0) {
133		pr_err("Can't parse timer1 IRQ\n");
134		return -EINVAL;
135	}
136
137	clk = of_clk_get(node, 0);
138	if (IS_ERR(clk)) {
139		ret = PTR_ERR(clk);
140		pr_err("Failed to get clock for clocksource (%d)\n", ret);
141		return ret;
142	}
143
144	rate = clk_get_rate(clk);
145
146	owl_timer_reset(owl_clksrc_base);
147	owl_timer_set_enabled(owl_clksrc_base, true);
148
149	sched_clock_register(owl_timer_sched_read, 32, rate);
150	ret = clocksource_mmio_init(owl_clksrc_base + OWL_Tx_VAL, node->name,
151				    rate, 200, 32, clocksource_mmio_readl_up);
152	if (ret) {
153		pr_err("Failed to register clocksource (%d)\n", ret);
154		return ret;
155	}
156
157	owl_timer_reset(owl_clkevt_base);
158
159	ret = request_irq(timer1_irq, owl_timer1_interrupt, IRQF_TIMER,
160			  "owl-timer", &owl_clockevent);
161	if (ret) {
162		pr_err("failed to request irq %d\n", timer1_irq);
163		return ret;
164	}
165
166	owl_clockevent.cpumask = cpumask_of(0);
167	owl_clockevent.irq = timer1_irq;
168
169	clockevents_config_and_register(&owl_clockevent, rate,
170					0xf, 0xffffffff);
171
172	return 0;
173}
174TIMER_OF_DECLARE(owl_s500, "actions,s500-timer", owl_timer_init);
175TIMER_OF_DECLARE(owl_s700, "actions,s700-timer", owl_timer_init);
176TIMER_OF_DECLARE(owl_s900, "actions,s900-timer", owl_timer_init);