1/*
  2 * Copyright (C) ST-Ericsson SA 2011
  3 *
  4 * License Terms: GNU General Public License v2
  5 * Author: Mattias Wallin <mattias.wallin@stericsson.com> for ST-Ericsson
  6 */
  7#include <linux/io.h>
  8#include <linux/errno.h>
  9#include <linux/clksrc-dbx500-prcmu.h>
 10#include <linux/of.h>
 11#include <linux/of_address.h>
 12
 13#include <asm/smp_twd.h>
 14
 15#include <plat/mtu.h>
 16
 17#include <mach/setup.h>
 18#include <mach/hardware.h>
 19#include <mach/irqs.h>
 20
 21#ifdef CONFIG_HAVE_ARM_TWD
 22static DEFINE_TWD_LOCAL_TIMER(u8500_twd_local_timer,
 23			      U8500_TWD_BASE, IRQ_LOCALTIMER);
 24
 25static void __init ux500_twd_init(void)
 26{
 27	struct twd_local_timer *twd_local_timer;
 28	int err;
 29
 30	/* Use this to switch local timer base if changed in new ASICs */
 31	twd_local_timer = &u8500_twd_local_timer;
 32
 33	if (of_have_populated_dt())
 34		twd_local_timer_of_register();
 35	else {
 36		err = twd_local_timer_register(twd_local_timer);
 37		if (err)
 38			pr_err("twd_local_timer_register failed %d\n", err);
 39	}
 40}
 41#else
 42#define ux500_twd_init()	do { } while(0)
 43#endif
 44
 45const static struct of_device_id prcmu_timer_of_match[] __initconst = {
 46	{ .compatible = "stericsson,db8500-prcmu-timer-4", },
 47	{ },
 48};
 49
 50static void __init ux500_timer_init(void)
 51{
 52	void __iomem *mtu_timer_base;
 53	void __iomem *prcmu_timer_base;
 54	void __iomem *tmp_base;
 55	struct device_node *np;
 56
 57	if (cpu_is_u8500_family()) {
 58		mtu_timer_base = __io_address(U8500_MTU0_BASE);
 59		prcmu_timer_base = __io_address(U8500_PRCMU_TIMER_4_BASE);
 60	} else {
 61		ux500_unknown_soc();
 62	}
 63
 64	/* TODO: Once MTU has been DT:ed place code above into else. */
 65	if (of_have_populated_dt()) {
 66#ifdef CONFIG_OF
 67		np = of_find_matching_node(NULL, prcmu_timer_of_match);
 68		if (!np)
 69#endif
 70			goto dt_fail;
 71
 72		tmp_base = of_iomap(np, 0);
 73		if (!tmp_base)
 74			goto dt_fail;
 75
 76		prcmu_timer_base = tmp_base;
 77	}
 78
 79dt_fail:
 80	/* Doing it the old fashioned way. */
 81
 82	/*
 83	 * Here we register the timerblocks active in the system.
 84	 * Localtimers (twd) is started when both cpu is up and running.
 85	 * MTU register a clocksource, clockevent and sched_clock.
 86	 * Since the MTU is located in the VAPE power domain
 87	 * it will be cleared in sleep which makes it unsuitable.
 88	 * We however need it as a timer tick (clockevent)
 89	 * during boot to calibrate delay until twd is started.
 90	 * RTC-RTT have problems as timer tick during boot since it is
 91	 * depending on delay which is not yet calibrated. RTC-RTT is in the
 92	 * always-on powerdomain and is used as clockevent instead of twd when
 93	 * sleeping.
 94	 * The PRCMU timer 4 register a clocksource and
 95	 * sched_clock with higher rating then MTU since is always-on.
 96	 *
 97	 */
 98
 99	nmdk_timer_init(mtu_timer_base);
100	clksrc_dbx500_prcmu_init(prcmu_timer_base);
101	ux500_twd_init();
102}
103
104static void ux500_timer_reset(void)
105{
106	nmdk_clkevt_reset();
107	nmdk_clksrc_reset();
108}
109
110struct sys_timer ux500_timer = {
111	.init		= ux500_timer_init,
112	.resume		= ux500_timer_reset,
113};