clocksource: clps711x: Add CLPS711X clocksource driver

This adds the clocksource driver for Cirrus Logic CLPS711X series SoCs.
Designed primarily for migration CLPS711X subarch for multiplatform & DT,
for this as the "OF" and "non-OF" calls implemented.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
This commit is contained in:
Alexander Shiyan 2014-07-13 08:45:13 +04:00 committed by Daniel Lezcano
parent 38941522ec
commit f0b7fabec3
2 changed files with 132 additions and 0 deletions

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@ -16,6 +16,7 @@ obj-$(CONFIG_CLKSRC_DBX500_PRCMU) += clksrc-dbx500-prcmu.o
obj-$(CONFIG_ARMADA_370_XP_TIMER) += time-armada-370-xp.o
obj-$(CONFIG_ORION_TIMER) += time-orion.o
obj-$(CONFIG_ARCH_BCM2835) += bcm2835_timer.o
obj-$(CONFIG_ARCH_CLPS711X) += clps711x-timer.o
obj-$(CONFIG_ARCH_MARCO) += timer-marco.o
obj-$(CONFIG_ARCH_MOXART) += moxart_timer.o
obj-$(CONFIG_ARCH_MXS) += mxs_timer.o

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@ -0,0 +1,131 @@
/*
* Cirrus Logic CLPS711X clocksource driver
*
* Copyright (C) 2014 Alexander Shiyan <shc_work@mail.ru>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/
#include <linux/clk.h>
#include <linux/clockchips.h>
#include <linux/clocksource.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/sched_clock.h>
#include <linux/slab.h>
enum {
CLPS711X_CLKSRC_CLOCKSOURCE,
CLPS711X_CLKSRC_CLOCKEVENT,
};
static void __iomem *tcd;
static u64 notrace clps711x_sched_clock_read(void)
{
return ~readw(tcd);
}
static int __init _clps711x_clksrc_init(struct clk *clock, void __iomem *base)
{
unsigned long rate;
if (!base)
return -ENOMEM;
if (IS_ERR(clock))
return PTR_ERR(clock);
rate = clk_get_rate(clock);
tcd = base;
clocksource_mmio_init(tcd, "clps711x-clocksource", rate, 300, 16,
clocksource_mmio_readw_down);
sched_clock_register(clps711x_sched_clock_read, 16, rate);
return 0;
}
static irqreturn_t clps711x_timer_interrupt(int irq, void *dev_id)
{
struct clock_event_device *evt = dev_id;
evt->event_handler(evt);
return IRQ_HANDLED;
}
static void clps711x_clockevent_set_mode(enum clock_event_mode mode,
struct clock_event_device *evt)
{
}
static int __init _clps711x_clkevt_init(struct clk *clock, void __iomem *base,
unsigned int irq)
{
struct clock_event_device *clkevt;
unsigned long rate;
if (!irq)
return -EINVAL;
if (!base)
return -ENOMEM;
if (IS_ERR(clock))
return PTR_ERR(clock);
clkevt = kzalloc(sizeof(*clkevt), GFP_KERNEL);
if (!clkevt)
return -ENOMEM;
rate = clk_get_rate(clock);
/* Set Timer prescaler */
writew(DIV_ROUND_CLOSEST(rate, HZ), base);
clkevt->name = "clps711x-clockevent";
clkevt->rating = 300;
clkevt->features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_C3STOP;
clkevt->set_mode = clps711x_clockevent_set_mode;
clkevt->cpumask = cpumask_of(0);
clockevents_config_and_register(clkevt, HZ, 0, 0);
return request_irq(irq, clps711x_timer_interrupt, IRQF_TIMER,
"clps711x-timer", clkevt);
}
void __init clps711x_clksrc_init(void __iomem *tc1_base, void __iomem *tc2_base,
unsigned int irq)
{
struct clk *tc1 = clk_get_sys("clps711x-timer.0", NULL);
struct clk *tc2 = clk_get_sys("clps711x-timer.1", NULL);
BUG_ON(_clps711x_clksrc_init(tc1, tc1_base));
BUG_ON(_clps711x_clkevt_init(tc2, tc2_base, irq));
}
#ifdef CONFIG_CLKSRC_OF
static void __init clps711x_timer_init(struct device_node *np)
{
unsigned int irq = irq_of_parse_and_map(np, 0);
struct clk *clock = of_clk_get(np, 0);
void __iomem *base = of_iomap(np, 0);
switch (of_alias_get_id(np, "timer")) {
case CLPS711X_CLKSRC_CLOCKSOURCE:
BUG_ON(_clps711x_clksrc_init(clock, base));
break;
case CLPS711X_CLKSRC_CLOCKEVENT:
BUG_ON(_clps711x_clkevt_init(clock, base, irq));
break;
default:
break;
}
}
CLOCKSOURCE_OF_DECLARE(clps711x, "cirrus,clps711x-timer", clps711x_timer_init);
#endif