Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull clocksource updates from Ingo Molnar:
 "Misc clocksource/clockevent driver updates that came in a bit late but
  are ready for v5.2"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  misc: atmel_tclib: Do not probe already used TCBs
  clocksource/drivers/timer-atmel-tcb: Convert tc_clksrc_suspend|resume() to static
  clocksource/drivers/tcb_clksrc: Rename the file for consistency
  clocksource/drivers/timer-atmel-pit: Rework Kconfig option
  clocksource/drivers/tcb_clksrc: Move Kconfig option
  ARM: at91: Implement clocksource selection
  clocksource/drivers/tcb_clksrc: Use tcb as sched_clock
  clocksource/drivers/tcb_clksrc: Stop depending on atmel_tclib
  ARM: at91: move SoC specific definitions to SoC folder
  clocksource/drivers/timer-milbeaut: Cleanup common register accesses
  clocksource/drivers/timer-milbeaut: Add shutdown function
  clocksource/drivers/timer-milbeaut: Fix to enable one-shot timer
  clocksource/drivers/tegra: Rework for compensation of suspend time
  clocksource/drivers/sp804: Add COMPILE_TEST to CONFIG_ARM_TIMER_SP804
  clocksource/drivers/sun4i: Add a compatible for suniv
  dt-bindings: timer: Add Allwinner suniv timer

6 files changed, 169 insertions, 107 deletions

diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index 48321488f0fd..6bcaa4e2e72c 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -387,7 +387,7 @@ config ARM_GLOBAL_TIMER
 	  This options enables support for the ARM global timer unit
 
 config ARM_TIMER_SP804
-	bool "Support for Dual Timer SP804 module"
+	bool "Support for Dual Timer SP804 module" if COMPILE_TEST
 	depends on GENERIC_SCHED_CLOCK && CLKDEV_LOOKUP
 	select CLKSRC_MMIO
 	select TIMER_OF if OF
@@ -407,8 +407,11 @@ config ARMV7M_SYSTICK
 	  This options enables support for the ARMv7M system timer unit
 
 config ATMEL_PIT
+	bool "Atmel PIT support" if COMPILE_TEST
+	depends on HAS_IOMEM
 	select TIMER_OF if OF
-	def_bool SOC_AT91SAM9 || SOC_SAMA5
+	help
+	  Support for the Periodic Interval Timer found on Atmel SoCs.
 
 config ATMEL_ST
 	bool "Atmel ST timer support" if COMPILE_TEST
@@ -418,6 +421,13 @@ config ATMEL_ST
 	help
 	  Support for the Atmel ST timer.
 
+config ATMEL_TCB_CLKSRC
+	bool "Atmel TC Block timer driver" if COMPILE_TEST
+	depends on HAS_IOMEM
+	select TIMER_OF if OF
+	help
+	  Support for Timer Counter Blocks on Atmel SoCs.
+
 config CLKSRC_EXYNOS_MCT
 	bool "Exynos multi core timer driver" if COMPILE_TEST
 	depends on ARM || ARM64
diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index dba4eff880de..236858fa7fbf 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -3,7 +3,7 @@ obj-$(CONFIG_TIMER_OF)		+= timer-of.o
 obj-$(CONFIG_TIMER_PROBE)	+= timer-probe.o
 obj-$(CONFIG_ATMEL_PIT)		+= timer-atmel-pit.o
 obj-$(CONFIG_ATMEL_ST)		+= timer-atmel-st.o
-obj-$(CONFIG_ATMEL_TCB_CLKSRC)	+= tcb_clksrc.o
+obj-$(CONFIG_ATMEL_TCB_CLKSRC)	+= timer-atmel-tcb.o
 obj-$(CONFIG_X86_PM_TIMER)	+= acpi_pm.o
 obj-$(CONFIG_SCx200HR_TIMER)	+= scx200_hrt.o
 obj-$(CONFIG_CS5535_CLOCK_EVENT_SRC)	+= timer-cs5535.o
diff --git a/drivers/clocksource/tcb_clksrc.c b/drivers/clocksource/timer-atmel-tcb.c
index f987027ca566..6ed31f9def7e 100644
--- a/drivers/clocksource/tcb_clksrc.c
+++ b/drivers/clocksource/timer-atmel-tcb.c
@@ -9,9 +9,11 @@
 #include <linux/err.h>
 #include <linux/ioport.h>
 #include <linux/io.h>
-#include <linux/platform_device.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/sched_clock.h>
 #include <linux/syscore_ops.h>
-#include <linux/atmel_tc.h>
+#include <soc/at91/atmel_tcb.h>
 
 
 /*
@@ -28,13 +30,6 @@
  *     source, used in either periodic or oneshot mode.  This runs
  *     at 32 KiHZ, and can handle delays of up to two seconds.
  *
- * A boot clocksource and clockevent source are also currently needed,
- * unless the relevant platforms (ARM/AT91, AVR32/AT32) are changed so
- * this code can be used when init_timers() is called, well before most
- * devices are set up.  (Some low end AT91 parts, which can run uClinux,
- * have only the timers in one TC block... they currently don't support
- * the tclib code, because of that initialization issue.)
- *
  * REVISIT behavior during system suspend states... we should disable
  * all clocks and save the power.  Easily done for clockevent devices,
  * but clocksources won't necessarily get the needed notifications.
@@ -112,7 +107,6 @@ static void tc_clksrc_resume(struct clocksource *cs)
 }
 
 static struct clocksource clksrc = {
-	.name           = "tcb_clksrc",
 	.rating         = 200,
 	.read           = tc_get_cycles,
 	.mask           = CLOCKSOURCE_MASK(32),
@@ -121,6 +115,16 @@ static struct clocksource clksrc = {
 	.resume		= tc_clksrc_resume,
 };
 
+static u64 notrace tc_sched_clock_read(void)
+{
+	return tc_get_cycles(&clksrc);
+}
+
+static u64 notrace tc_sched_clock_read32(void)
+{
+	return tc_get_cycles32(&clksrc);
+}
+
 #ifdef CONFIG_GENERIC_CLOCKEVENTS
 
 struct tc_clkevt_device {
@@ -214,7 +218,6 @@ static int tc_next_event(unsigned long delta, struct clock_event_device *d)
 
 static struct tc_clkevt_device clkevt = {
 	.clkevt	= {
-		.name			= "tc_clkevt",
 		.features		= CLOCK_EVT_FEAT_PERIODIC |
 					  CLOCK_EVT_FEAT_ONESHOT,
 		/* Should be lower than at91rm9200's system timer */
@@ -330,39 +333,74 @@ static void __init tcb_setup_single_chan(struct atmel_tc *tc, int mck_divisor_id
 	writel(ATMEL_TC_SYNC, tcaddr + ATMEL_TC_BCR);
 }
 
-static int __init tcb_clksrc_init(void)
-{
-	static char bootinfo[] __initdata
-		= KERN_DEBUG "%s: tc%d at %d.%03d MHz\n";
+static const u8 atmel_tcb_divisors[5] = { 2, 8, 32, 128, 0, };
+
+static const struct of_device_id atmel_tcb_of_match[] = {
+	{ .compatible = "atmel,at91rm9200-tcb", .data = (void *)16, },
+	{ .compatible = "atmel,at91sam9x5-tcb", .data = (void *)32, },
+	{ /* sentinel */ }
+};
 
-	struct platform_device *pdev;
-	struct atmel_tc *tc;
+static int __init tcb_clksrc_init(struct device_node *node)
+{
+	struct atmel_tc tc;
 	struct clk *t0_clk;
+	const struct of_device_id *match;
+	u64 (*tc_sched_clock)(void);
 	u32 rate, divided_rate = 0;
 	int best_divisor_idx = -1;
 	int clk32k_divisor_idx = -1;
+	int bits;
 	int i;
 	int ret;
 
-	tc = atmel_tc_alloc(CONFIG_ATMEL_TCB_CLKSRC_BLOCK);
-	if (!tc) {
-		pr_debug("can't alloc TC for clocksource\n");
-		return -ENODEV;
+	/* Protect against multiple calls */
+	if (tcaddr)
+		return 0;
+
+	tc.regs = of_iomap(node->parent, 0);
+	if (!tc.regs)
+		return -ENXIO;
+
+	t0_clk = of_clk_get_by_name(node->parent, "t0_clk");
+	if (IS_ERR(t0_clk))
+		return PTR_ERR(t0_clk);
+
+	tc.slow_clk = of_clk_get_by_name(node->parent, "slow_clk");
+	if (IS_ERR(tc.slow_clk))
+		return PTR_ERR(tc.slow_clk);
+
+	tc.clk[0] = t0_clk;
+	tc.clk[1] = of_clk_get_by_name(node->parent, "t1_clk");
+	if (IS_ERR(tc.clk[1]))
+		tc.clk[1] = t0_clk;
+	tc.clk[2] = of_clk_get_by_name(node->parent, "t2_clk");
+	if (IS_ERR(tc.clk[2]))
+		tc.clk[2] = t0_clk;
+
+	tc.irq[2] = of_irq_get(node->parent, 2);
+	if (tc.irq[2] <= 0) {
+		tc.irq[2] = of_irq_get(node->parent, 0);
+		if (tc.irq[2] <= 0)
+			return -EINVAL;
 	}
-	tcaddr = tc->regs;
-	pdev = tc->pdev;
 
-	t0_clk = tc->clk[0];
+	match = of_match_node(atmel_tcb_of_match, node->parent);
+	bits = (uintptr_t)match->data;
+
+	for (i = 0; i < ARRAY_SIZE(tc.irq); i++)
+		writel(ATMEL_TC_ALL_IRQ, tc.regs + ATMEL_TC_REG(i, IDR));
+
 	ret = clk_prepare_enable(t0_clk);
 	if (ret) {
 		pr_debug("can't enable T0 clk\n");
-		goto err_free_tc;
+		return ret;
 	}
 
 	/* How fast will we be counting?  Pick something over 5 MHz.  */
 	rate = (u32) clk_get_rate(t0_clk);
-	for (i = 0; i < 5; i++) {
-		unsigned divisor = atmel_tc_divisors[i];
+	for (i = 0; i < ARRAY_SIZE(atmel_tcb_divisors); i++) {
+		unsigned divisor = atmel_tcb_divisors[i];
 		unsigned tmp;
 
 		/* remember 32 KiHz clock for later */
@@ -381,27 +419,31 @@ static int __init tcb_clksrc_init(void)
 		best_divisor_idx = i;
 	}
 
-
-	printk(bootinfo, clksrc.name, CONFIG_ATMEL_TCB_CLKSRC_BLOCK,
-			divided_rate / 1000000,
+	clksrc.name = kbasename(node->parent->full_name);
+	clkevt.clkevt.name = kbasename(node->parent->full_name);
+	pr_debug("%s at %d.%03d MHz\n", clksrc.name, divided_rate / 1000000,
 			((divided_rate % 1000000) + 500) / 1000);
 
-	if (tc->tcb_config && tc->tcb_config->counter_width == 32) {
+	tcaddr = tc.regs;
+
+	if (bits == 32) {
 		/* use apropriate function to read 32 bit counter */
 		clksrc.read = tc_get_cycles32;
 		/* setup ony channel 0 */
-		tcb_setup_single_chan(tc, best_divisor_idx);
+		tcb_setup_single_chan(&tc, best_divisor_idx);
+		tc_sched_clock = tc_sched_clock_read32;
 	} else {
-		/* tclib will give us three clocks no matter what the
+		/* we have three clocks no matter what the
 		 * underlying platform supports.
 		 */
-		ret = clk_prepare_enable(tc->clk[1]);
+		ret = clk_prepare_enable(tc.clk[1]);
 		if (ret) {
 			pr_debug("can't enable T1 clk\n");
 			goto err_disable_t0;
 		}
 		/* setup both channel 0 & 1 */
-		tcb_setup_dual_chan(tc, best_divisor_idx);
+		tcb_setup_dual_chan(&tc, best_divisor_idx);
+		tc_sched_clock = tc_sched_clock_read;
 	}
 
 	/* and away we go! */
@@ -410,24 +452,26 @@ static int __init tcb_clksrc_init(void)
 		goto err_disable_t1;
 
 	/* channel 2:  periodic and oneshot timer support */
-	ret = setup_clkevents(tc, clk32k_divisor_idx);
+	ret = setup_clkevents(&tc, clk32k_divisor_idx);
 	if (ret)
 		goto err_unregister_clksrc;
 
+	sched_clock_register(tc_sched_clock, 32, divided_rate);
+
 	return 0;
 
 err_unregister_clksrc:
 	clocksource_unregister(&clksrc);
 
 err_disable_t1:
-	if (!tc->tcb_config || tc->tcb_config->counter_width != 32)
-		clk_disable_unprepare(tc->clk[1]);
+	if (bits != 32)
+		clk_disable_unprepare(tc.clk[1]);
 
 err_disable_t0:
 	clk_disable_unprepare(t0_clk);
 
-err_free_tc:
-	atmel_tc_free(tc);
+	tcaddr = NULL;
+
 	return ret;
 }
-arch_initcall(tcb_clksrc_init);
+TIMER_OF_DECLARE(atmel_tcb_clksrc, "atmel,tcb-timer", tcb_clksrc_init);
diff --git a/drivers/clocksource/timer-milbeaut.c b/drivers/clocksource/timer-milbeaut.c
index f2019a88e3ee..fa9fb4eacade 100644
--- a/drivers/clocksource/timer-milbeaut.c
+++ b/drivers/clocksource/timer-milbeaut.c
@@ -26,8 +26,8 @@
 #define MLB_TMR_TMCSR_CSL_DIV2	0
 #define MLB_TMR_DIV_CNT		2
 
-#define MLB_TMR_SRC_CH  (1)
-#define MLB_TMR_EVT_CH  (0)
+#define MLB_TMR_SRC_CH		1
+#define MLB_TMR_EVT_CH		0
 
 #define MLB_TMR_SRC_CH_OFS	(MLB_TMR_REGSZPCH * MLB_TMR_SRC_CH)
 #define MLB_TMR_EVT_CH_OFS	(MLB_TMR_REGSZPCH * MLB_TMR_EVT_CH)
@@ -43,6 +43,8 @@
 #define MLB_TMR_EVT_TMRLR2_OFS	(MLB_TMR_EVT_CH_OFS + MLB_TMR_TMRLR2_OFS)
 
 #define MLB_TIMER_RATING	500
+#define MLB_TIMER_ONESHOT	0
+#define MLB_TIMER_PERIODIC	1
 
 static irqreturn_t mlb_timer_interrupt(int irq, void *dev_id)
 {
@@ -59,27 +61,53 @@ static irqreturn_t mlb_timer_interrupt(int irq, void *dev_id)
 	return IRQ_HANDLED;
 }
 
-static int mlb_set_state_periodic(struct clock_event_device *clk)
+static void mlb_evt_timer_start(struct timer_of *to, bool periodic)
 {
-	struct timer_of *to = to_timer_of(clk);
 	u32 val = MLB_TMR_TMCSR_CSL_DIV2;
 
+	val |= MLB_TMR_TMCSR_CNTE | MLB_TMR_TMCSR_TRG | MLB_TMR_TMCSR_INTE;
+	if (periodic)
+		val |= MLB_TMR_TMCSR_RELD;
 	writel_relaxed(val, timer_of_base(to) + MLB_TMR_EVT_TMCSR_OFS);
+}
 
-	writel_relaxed(to->of_clk.period, timer_of_base(to) +
-				MLB_TMR_EVT_TMRLR1_OFS);
-	val |= MLB_TMR_TMCSR_RELD | MLB_TMR_TMCSR_CNTE |
-		MLB_TMR_TMCSR_TRG | MLB_TMR_TMCSR_INTE;
+static void mlb_evt_timer_stop(struct timer_of *to)
+{
+	u32 val = readl_relaxed(timer_of_base(to) + MLB_TMR_EVT_TMCSR_OFS);
+
+	val &= ~MLB_TMR_TMCSR_CNTE;
 	writel_relaxed(val, timer_of_base(to) + MLB_TMR_EVT_TMCSR_OFS);
+}
+
+static void mlb_evt_timer_register_count(struct timer_of *to, unsigned long cnt)
+{
+	writel_relaxed(cnt, timer_of_base(to) + MLB_TMR_EVT_TMRLR1_OFS);
+}
+
+static int mlb_set_state_periodic(struct clock_event_device *clk)
+{
+	struct timer_of *to = to_timer_of(clk);
+
+	mlb_evt_timer_stop(to);
+	mlb_evt_timer_register_count(to, to->of_clk.period);
+	mlb_evt_timer_start(to, MLB_TIMER_PERIODIC);
 	return 0;
 }
 
 static int mlb_set_state_oneshot(struct clock_event_device *clk)
 {
 	struct timer_of *to = to_timer_of(clk);
-	u32 val = MLB_TMR_TMCSR_CSL_DIV2;
 
-	writel_relaxed(val, timer_of_base(to) + MLB_TMR_EVT_TMCSR_OFS);
+	mlb_evt_timer_stop(to);
+	mlb_evt_timer_start(to, MLB_TIMER_ONESHOT);
+	return 0;
+}
+
+static int mlb_set_state_shutdown(struct clock_event_device *clk)
+{
+	struct timer_of *to = to_timer_of(clk);
+
+	mlb_evt_timer_stop(to);
 	return 0;
 }
 
@@ -88,22 +116,21 @@ static int mlb_clkevt_next_event(unsigned long event,
 {
 	struct timer_of *to = to_timer_of(clk);
 
-	writel_relaxed(event, timer_of_base(to) + MLB_TMR_EVT_TMRLR1_OFS);
-	writel_relaxed(MLB_TMR_TMCSR_CSL_DIV2 |
-			MLB_TMR_TMCSR_CNTE | MLB_TMR_TMCSR_INTE |
-			MLB_TMR_TMCSR_TRG, timer_of_base(to) +
-			MLB_TMR_EVT_TMCSR_OFS);
+	mlb_evt_timer_stop(to);
+	mlb_evt_timer_register_count(to, event);
+	mlb_evt_timer_start(to, MLB_TIMER_ONESHOT);
 	return 0;
 }
 
 static int mlb_config_clock_source(struct timer_of *to)
 {
-	writel_relaxed(0, timer_of_base(to) + MLB_TMR_SRC_TMCSR_OFS);
-	writel_relaxed(~0, timer_of_base(to) + MLB_TMR_SRC_TMR_OFS);
+	u32 val = MLB_TMR_TMCSR_CSL_DIV2;
+
+	writel_relaxed(val, timer_of_base(to) + MLB_TMR_SRC_TMCSR_OFS);
 	writel_relaxed(~0, timer_of_base(to) + MLB_TMR_SRC_TMRLR1_OFS);
 	writel_relaxed(~0, timer_of_base(to) + MLB_TMR_SRC_TMRLR2_OFS);
-	writel_relaxed(BIT(4) | BIT(1) | BIT(0), timer_of_base(to) +
-		MLB_TMR_SRC_TMCSR_OFS);
+	val |= MLB_TMR_TMCSR_RELD | MLB_TMR_TMCSR_CNTE | MLB_TMR_TMCSR_TRG;
+	writel_relaxed(val, timer_of_base(to) + MLB_TMR_SRC_TMCSR_OFS);
 	return 0;
 }
 
@@ -123,6 +150,7 @@ static struct timer_of to = {
 		.features = CLOCK_EVT_FEAT_DYNIRQ | CLOCK_EVT_FEAT_ONESHOT,
 		.set_state_oneshot = mlb_set_state_oneshot,
 		.set_state_periodic = mlb_set_state_periodic,
+		.set_state_shutdown = mlb_set_state_shutdown,
 		.set_next_event = mlb_clkevt_next_event,
 	},
 
diff --git a/drivers/clocksource/timer-sun4i.c b/drivers/clocksource/timer-sun4i.c
index 6e0180aaf784..65f38f6ca714 100644
--- a/drivers/clocksource/timer-sun4i.c
+++ b/drivers/clocksource/timer-sun4i.c
@@ -186,7 +186,8 @@ static int __init sun4i_timer_init(struct device_node *node)
 	 */
 	if (of_machine_is_compatible("allwinner,sun4i-a10") ||
 	    of_machine_is_compatible("allwinner,sun5i-a13") ||
-	    of_machine_is_compatible("allwinner,sun5i-a10s"))
+	    of_machine_is_compatible("allwinner,sun5i-a10s") ||
+	    of_machine_is_compatible("allwinner,suniv-f1c100s"))
 		sched_clock_register(sun4i_timer_sched_read, 32,
 				     timer_of_rate(&to));
 
@@ -218,3 +219,5 @@ static int __init sun4i_timer_init(struct device_node *node)
 }
 TIMER_OF_DECLARE(sun4i, "allwinner,sun4i-a10-timer",
 		       sun4i_timer_init);
+TIMER_OF_DECLARE(suniv, "allwinner,suniv-f1c100s-timer",
+		       sun4i_timer_init);
diff --git a/drivers/clocksource/timer-tegra20.c b/drivers/clocksource/timer-tegra20.c
index fdb3d795a409..919b3568c495 100644
--- a/drivers/clocksource/timer-tegra20.c
+++ b/drivers/clocksource/timer-tegra20.c
@@ -60,9 +60,6 @@
 static u32 usec_config;
 static void __iomem *timer_reg_base;
 #ifdef CONFIG_ARM
-static void __iomem *rtc_base;
-static struct timespec64 persistent_ts;
-static u64 persistent_ms, last_persistent_ms;
 static struct delay_timer tegra_delay_timer;
 #endif
 
@@ -199,40 +196,30 @@ static unsigned long tegra_delay_timer_read_counter_long(void)
 	return readl(timer_reg_base + TIMERUS_CNTR_1US);
 }
 
+static struct timer_of suspend_rtc_to = {
+	.flags = TIMER_OF_BASE | TIMER_OF_CLOCK,
+};
+
 /*
  * tegra_rtc_read - Reads the Tegra RTC registers
  * Care must be taken that this funciton is not called while the
  * tegra_rtc driver could be executing to avoid race conditions
  * on the RTC shadow register
  */
-static u64 tegra_rtc_read_ms(void)
+static u64 tegra_rtc_read_ms(struct clocksource *cs)
 {
-	u32 ms = readl(rtc_base + RTC_MILLISECONDS);
-	u32 s = readl(rtc_base + RTC_SHADOW_SECONDS);
+	u32 ms = readl(timer_of_base(&suspend_rtc_to) + RTC_MILLISECONDS);
+	u32 s = readl(timer_of_base(&suspend_rtc_to) + RTC_SHADOW_SECONDS);
 	return (u64)s * MSEC_PER_SEC + ms;
 }
 
-/*
- * tegra_read_persistent_clock64 -  Return time from a persistent clock.
- *
- * Reads the time from a source which isn't disabled during PM, the
- * 32k sync timer.  Convert the cycles elapsed since last read into
- * nsecs and adds to a monotonically increasing timespec64.
- * Care must be taken that this funciton is not called while the
- * tegra_rtc driver could be executing to avoid race conditions
- * on the RTC shadow register
- */
-static void tegra_read_persistent_clock64(struct timespec64 *ts)
-{
-	u64 delta;
-
-	last_persistent_ms = persistent_ms;
-	persistent_ms = tegra_rtc_read_ms();
-	delta = persistent_ms - last_persistent_ms;
-
-	timespec64_add_ns(&persistent_ts, delta * NSEC_PER_MSEC);
-	*ts = persistent_ts;
-}
+static struct clocksource suspend_rtc_clocksource = {
+	.name	= "tegra_suspend_timer",
+	.rating	= 200,
+	.read	= tegra_rtc_read_ms,
+	.mask	= CLOCKSOURCE_MASK(32),
+	.flags	= CLOCK_SOURCE_IS_CONTINUOUS | CLOCK_SOURCE_SUSPEND_NONSTOP,
+};
 #endif
 
 static int tegra_timer_common_init(struct device_node *np, struct timer_of *to)
@@ -385,25 +372,15 @@ out:
 
 static int __init tegra20_init_rtc(struct device_node *np)
 {
-	struct clk *clk;
+	int ret;
 
-	rtc_base = of_iomap(np, 0);
-	if (!rtc_base) {
-		pr_err("Can't map RTC registers\n");
-		return -ENXIO;
-	}
+	ret = timer_of_init(np, &suspend_rtc_to);
+	if (ret)
+		return ret;
 
-	/*
-	 * rtc registers are used by read_persistent_clock, keep the rtc clock
-	 * enabled
-	 */
-	clk = of_clk_get(np, 0);
-	if (IS_ERR(clk))
-		pr_warn("Unable to get rtc-tegra clock\n");
-	else
-		clk_prepare_enable(clk);
+	clocksource_register_hz(&suspend_rtc_clocksource, 1000);
 
-	return register_persistent_clock(tegra_read_persistent_clock64);
+	return 0;
 }
 TIMER_OF_DECLARE(tegra20_rtc, "nvidia,tegra20-rtc", tegra20_init_rtc);
 #endif