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| author | Olof Johansson <olof@lixom.net> | 2013-04-11 03:39:00 -0700 | 
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| committer | Olof Johansson <olof@lixom.net> | 2013-04-11 03:39:00 -0700 | 
| commit | b9d5868e342a9802db7b299be511ac547ff1034d (patch) | |
| tree | 49c8fe5467b817bcaf2afa6468c2e362f50e4770 /drivers/clocksource/sun4i_timer.c | |
| parent | 83c15f4c05757b3c5fe1551a474458fd16d27bae (diff) | |
| parent | bc34b5f27cd33f4213bc5c8df0099dd11408d29d (diff) | |
| download | olio-linux-3.10-b9d5868e342a9802db7b299be511ac547ff1034d.tar.xz olio-linux-3.10-b9d5868e342a9802db7b299be511ac547ff1034d.zip  | |
Merge tag 'sunxi-cleanup-for-3.10' of git://github.com/mripard/linux into next/cleanup
From Maxime Ripard:
Cleanups for Allwinner sunXi architecture:
  - Remove sunxi.dtsi
  - Switch to clocksource/irqchip device tree handlers
  - Cleanup the watchdog code
* tag 'sunxi-cleanup-for-3.10' of git://github.com/mripard/linux:
  ARM: sunxi: Rework the restart code
  irqchip: sunxi: Rename sunxi to sun4i
  irqchip: sunxi: Make use of the IRQCHIP_DECLARE macro
  clocksource: sunxi: Rename sunxi to sun4i
  clocksource: sunxi: make use of CLKSRC_OF
  clocksource: sunxi: Cleanup the timer code
  clocksource: make CLOCKSOURCE_OF_DECLARE type safe
Signed-off-by: Olof Johansson <olof@lixom.net>
Add/change conflict in drivers/clocksource/Makefile resolved.
Diffstat (limited to 'drivers/clocksource/sun4i_timer.c')
| -rw-r--r-- | drivers/clocksource/sun4i_timer.c | 148 | 
1 files changed, 148 insertions, 0 deletions
diff --git a/drivers/clocksource/sun4i_timer.c b/drivers/clocksource/sun4i_timer.c new file mode 100644 index 00000000000..d4674e78ef3 --- /dev/null +++ b/drivers/clocksource/sun4i_timer.c @@ -0,0 +1,148 @@ +/* + * Allwinner A1X SoCs timer handling. + * + * Copyright (C) 2012 Maxime Ripard + * + * Maxime Ripard <maxime.ripard@free-electrons.com> + * + * Based on code from + * Allwinner Technology Co., Ltd. <www.allwinnertech.com> + * Benn Huang <benn@allwinnertech.com> + * + * This file is licensed under the terms of the GNU General Public + * License version 2.  This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#include <linux/clk.h> +#include <linux/clockchips.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/irqreturn.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> + +#define TIMER_IRQ_EN_REG	0x00 +#define TIMER_IRQ_EN(val)		(1 << val) +#define TIMER_IRQ_ST_REG	0x04 +#define TIMER_CTL_REG(val)	(0x10 * val + 0x10) +#define TIMER_CTL_ENABLE		(1 << 0) +#define TIMER_CTL_AUTORELOAD		(1 << 1) +#define TIMER_CTL_ONESHOT		(1 << 7) +#define TIMER_INTVAL_REG(val)	(0x10 * val + 0x14) +#define TIMER_CNTVAL_REG(val)	(0x10 * val + 0x18) + +#define TIMER_SCAL		16 + +static void __iomem *timer_base; + +static void sun4i_clkevt_mode(enum clock_event_mode mode, +			      struct clock_event_device *clk) +{ +	u32 u = readl(timer_base + TIMER_CTL_REG(0)); + +	switch (mode) { +	case CLOCK_EVT_MODE_PERIODIC: +		u &= ~(TIMER_CTL_ONESHOT); +		writel(u | TIMER_CTL_ENABLE, timer_base + TIMER_CTL_REG(0)); +		break; + +	case CLOCK_EVT_MODE_ONESHOT: +		writel(u | TIMER_CTL_ONESHOT, timer_base + TIMER_CTL_REG(0)); +		break; +	case CLOCK_EVT_MODE_UNUSED: +	case CLOCK_EVT_MODE_SHUTDOWN: +	default: +		writel(u & ~(TIMER_CTL_ENABLE), timer_base + TIMER_CTL_REG(0)); +		break; +	} +} + +static int sun4i_clkevt_next_event(unsigned long evt, +				   struct clock_event_device *unused) +{ +	u32 u = readl(timer_base + TIMER_CTL_REG(0)); +	writel(evt, timer_base + TIMER_CNTVAL_REG(0)); +	writel(u | TIMER_CTL_ENABLE | TIMER_CTL_AUTORELOAD, +	       timer_base + TIMER_CTL_REG(0)); + +	return 0; +} + +static struct clock_event_device sun4i_clockevent = { +	.name = "sun4i_tick", +	.rating = 300, +	.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT, +	.set_mode = sun4i_clkevt_mode, +	.set_next_event = sun4i_clkevt_next_event, +}; + + +static irqreturn_t sun4i_timer_interrupt(int irq, void *dev_id) +{ +	struct clock_event_device *evt = (struct clock_event_device *)dev_id; + +	writel(0x1, timer_base + TIMER_IRQ_ST_REG); +	evt->event_handler(evt); + +	return IRQ_HANDLED; +} + +static struct irqaction sun4i_timer_irq = { +	.name = "sun4i_timer0", +	.flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL, +	.handler = sun4i_timer_interrupt, +	.dev_id = &sun4i_clockevent, +}; + +static void __init sun4i_timer_init(struct device_node *node) +{ +	unsigned long rate = 0; +	struct clk *clk; +	int ret, irq; +	u32 val; + +	timer_base = of_iomap(node, 0); +	if (!timer_base) +		panic("Can't map registers"); + +	irq = irq_of_parse_and_map(node, 0); +	if (irq <= 0) +		panic("Can't parse IRQ"); + +	clk = of_clk_get(node, 0); +	if (IS_ERR(clk)) +		panic("Can't get timer clock"); + +	rate = clk_get_rate(clk); + +	writel(rate / (TIMER_SCAL * HZ), +	       timer_base + TIMER_INTVAL_REG(0)); + +	/* set clock source to HOSC, 16 pre-division */ +	val = readl(timer_base + TIMER_CTL_REG(0)); +	val &= ~(0x07 << 4); +	val &= ~(0x03 << 2); +	val |= (4 << 4) | (1 << 2); +	writel(val, timer_base + TIMER_CTL_REG(0)); + +	/* set mode to auto reload */ +	val = readl(timer_base + TIMER_CTL_REG(0)); +	writel(val | TIMER_CTL_AUTORELOAD, timer_base + TIMER_CTL_REG(0)); + +	ret = setup_irq(irq, &sun4i_timer_irq); +	if (ret) +		pr_warn("failed to setup irq %d\n", irq); + +	/* Enable timer0 interrupt */ +	val = readl(timer_base + TIMER_IRQ_EN_REG); +	writel(val | TIMER_IRQ_EN(0), timer_base + TIMER_IRQ_EN_REG); + +	sun4i_clockevent.cpumask = cpumask_of(0); + +	clockevents_config_and_register(&sun4i_clockevent, rate / TIMER_SCAL, +					0x1, 0xff); +} +CLOCKSOURCE_OF_DECLARE(sun4i, "allwinner,sun4i-timer", +		       sun4i_timer_init);  |