From 19b0a1e5ac5a7f1dafd5ee2479a5db72b330246b Mon Sep 17 00:00:00 2001
From: Stephen Boyd <sboyd@codeaurora.org>
Date: Wed, 17 Jul 2013 19:39:19 -0700
Subject: [PATCH 01/23] clocksource: orion: Use linux/sched_clock.h

The sched_clock.h include is under include/linux now.

Cc: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
---
 drivers/clocksource/time-orion.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/clocksource/time-orion.c b/drivers/clocksource/time-orion.c
index ecbeb6810215..9c7f018a67ca 100644
--- a/drivers/clocksource/time-orion.c
+++ b/drivers/clocksource/time-orion.c
@@ -19,7 +19,7 @@
 #include <linux/of_address.h>
 #include <linux/of_irq.h>
 #include <linux/spinlock.h>
-#include <asm/sched_clock.h>
+#include <linux/sched_clock.h>
 
 #define TIMER_CTRL		0x00
 #define  TIMER0_EN		BIT(0)

From 9222d247bcbaacc40fe15549158f9d67523c1ace Mon Sep 17 00:00:00 2001
From: John Stultz <john.stultz@linaro.org>
Date: Tue, 16 Jul 2013 16:45:31 +0200
Subject: [PATCH 02/23] MAINTAINERS: Add Daniel as maintainer for CLOCKSOURCE
 and CLOCKEVENT Drivers

I've been doing a bad job at managing the drivers/clocksource directory,
so Daniel has been helping with review and patch queuing for the clocksource
and clockevent drivers, so add him formally to the MAINTAINERS list.

Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Joe Perches <joe@perches.com>
Cc: Arnd Bergmann <arnd.bergmann@linaro.org>
Cc: Olof Johansson <olof@lixom.net>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
---
 MAINTAINERS | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/MAINTAINERS b/MAINTAINERS
index bf61e04291ab..12a1ef44ca83 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2107,6 +2107,13 @@ M:	Russell King <linux@arm.linux.org.uk>
 S:	Maintained
 F:	include/linux/clk.h
 
+CLOCKSOURCE, CLOCKEVENT DRIVERS
+M:	Daniel Lezcano <daniel.lezcano@linaro.org>
+M:	Thomas Gleixner <tglx@linutronix.de>
+T:	git git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git timers/core
+S:	Supported
+F:	drivers/clocksource
+
 CISCO FCOE HBA DRIVER
 M:	Hiral Patel <hiralpat@cisco.com>
 M:	Suma Ramars <sramars@cisco.com>
@@ -7123,7 +7130,7 @@ S:	Maintained
 F:	include/linux/mmc/dw_mmc.h
 F:	drivers/mmc/host/dw_mmc*
 
-TIMEKEEPING, NTP
+TIMEKEEPING, CLOCKSOURCE CORE, NTP
 M:	John Stultz <john.stultz@linaro.org>
 M:	Thomas Gleixner <tglx@linutronix.de>
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git timers/core
@@ -7136,7 +7143,6 @@ F:	include/uapi/linux/timex.h
 F:	kernel/time/clocksource.c
 F:	kernel/time/time*.c
 F:	kernel/time/ntp.c
-F:	drivers/clocksource
 
 TLG2300 VIDEO4LINUX-2 DRIVER
 M:	Huang Shijie <shijie8@gmail.com>

From 40777645eb7fe5b9184b339e1a8aa889993f6d75 Mon Sep 17 00:00:00 2001
From: Maxime Ripard <maxime.ripard@free-electrons.com>
Date: Tue, 16 Jul 2013 16:45:37 +0200
Subject: [PATCH 03/23] clocksource: sun4i: Use the BIT macros where possible

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
---
 drivers/clocksource/sun4i_timer.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/clocksource/sun4i_timer.c b/drivers/clocksource/sun4i_timer.c
index d4674e78ef35..bdf34d9910cb 100644
--- a/drivers/clocksource/sun4i_timer.c
+++ b/drivers/clocksource/sun4i_timer.c
@@ -24,12 +24,12 @@
 #include <linux/of_irq.h>
 
 #define TIMER_IRQ_EN_REG	0x00
-#define TIMER_IRQ_EN(val)		(1 << val)
+#define TIMER_IRQ_EN(val)		BIT(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_CTL_ENABLE		BIT(0)
+#define TIMER_CTL_AUTORELOAD		BIT(1)
+#define TIMER_CTL_ONESHOT		BIT(7)
 #define TIMER_INTVAL_REG(val)	(0x10 * val + 0x14)
 #define TIMER_CNTVAL_REG(val)	(0x10 * val + 0x18)
 

From bb008b9e873f5544120dcd401316b4c0e7743dde Mon Sep 17 00:00:00 2001
From: Maxime Ripard <maxime.ripard@free-electrons.com>
Date: Tue, 16 Jul 2013 16:45:37 +0200
Subject: [PATCH 04/23] clocksource: sun4i: Wrap macros arguments in
 parenthesis

The macros were not using parenthesis to escape the arguments passed to
them. It is pretty unsafe, so add those parenthesis.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
---
 drivers/clocksource/sun4i_timer.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/clocksource/sun4i_timer.c b/drivers/clocksource/sun4i_timer.c
index bdf34d9910cb..34ab6580ad1c 100644
--- a/drivers/clocksource/sun4i_timer.c
+++ b/drivers/clocksource/sun4i_timer.c
@@ -30,8 +30,8 @@
 #define TIMER_CTL_ENABLE		BIT(0)
 #define TIMER_CTL_AUTORELOAD		BIT(1)
 #define TIMER_CTL_ONESHOT		BIT(7)
-#define TIMER_INTVAL_REG(val)	(0x10 * val + 0x14)
-#define TIMER_CNTVAL_REG(val)	(0x10 * val + 0x18)
+#define TIMER_INTVAL_REG(val)	(0x10 * (val) + 0x14)
+#define TIMER_CNTVAL_REG(val)	(0x10 * (val) + 0x18)
 
 #define TIMER_SCAL		16
 

From 9eded23215e99338155c18f6d860859106568bb0 Mon Sep 17 00:00:00 2001
From: Maxime Ripard <maxime.ripard@free-electrons.com>
Date: Tue, 16 Jul 2013 16:45:37 +0200
Subject: [PATCH 05/23] clocksource: sun4i: rename AUTORELOAD define to RELOAD

The name AUTORELOAD was actually pretty bad since it doesn't make the
register reload the previous interval when it expires, but setting this
value pushes the new programmed interval to the internal timer counter.
Rename it to RELOAD instead.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
---
 drivers/clocksource/sun4i_timer.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/clocksource/sun4i_timer.c b/drivers/clocksource/sun4i_timer.c
index 34ab6580ad1c..f5e227b06ad5 100644
--- a/drivers/clocksource/sun4i_timer.c
+++ b/drivers/clocksource/sun4i_timer.c
@@ -28,7 +28,7 @@
 #define TIMER_IRQ_ST_REG	0x04
 #define TIMER_CTL_REG(val)	(0x10 * val + 0x10)
 #define TIMER_CTL_ENABLE		BIT(0)
-#define TIMER_CTL_AUTORELOAD		BIT(1)
+#define TIMER_CTL_RELOAD		BIT(1)
 #define TIMER_CTL_ONESHOT		BIT(7)
 #define TIMER_INTVAL_REG(val)	(0x10 * (val) + 0x14)
 #define TIMER_CNTVAL_REG(val)	(0x10 * (val) + 0x18)
@@ -129,7 +129,7 @@ static void __init sun4i_timer_init(struct device_node *node)
 
 	/* set mode to auto reload */
 	val = readl(timer_base + TIMER_CTL_REG(0));
-	writel(val | TIMER_CTL_AUTORELOAD, timer_base + TIMER_CTL_REG(0));
+	writel(val | TIMER_CTL_RELOAD, timer_base + TIMER_CTL_REG(0));
 
 	ret = setup_irq(irq, &sun4i_timer_irq);
 	if (ret)

From 137c6b3c7c63944a9cb51de0870b72f62d240f62 Mon Sep 17 00:00:00 2001
From: Maxime Ripard <maxime.ripard@free-electrons.com>
Date: Tue, 16 Jul 2013 16:45:37 +0200
Subject: [PATCH 06/23] clocksource: sun4i: Add clocksource and sched clock
 drivers

Use the second timer found on the Allwinner SoCs as a clock source and
sched clock, that were both not used yet on these platforms.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
---
 drivers/clocksource/sun4i_timer.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/drivers/clocksource/sun4i_timer.c b/drivers/clocksource/sun4i_timer.c
index f5e227b06ad5..b581c93f20b3 100644
--- a/drivers/clocksource/sun4i_timer.c
+++ b/drivers/clocksource/sun4i_timer.c
@@ -19,6 +19,7 @@
 #include <linux/interrupt.h>
 #include <linux/irq.h>
 #include <linux/irqreturn.h>
+#include <linux/sched_clock.h>
 #include <linux/of.h>
 #include <linux/of_address.h>
 #include <linux/of_irq.h>
@@ -96,6 +97,11 @@ static struct irqaction sun4i_timer_irq = {
 	.dev_id = &sun4i_clockevent,
 };
 
+static u32 sun4i_timer_sched_read(void)
+{
+	return ~readl(timer_base + TIMER_CNTVAL_REG(1));
+}
+
 static void __init sun4i_timer_init(struct device_node *node)
 {
 	unsigned long rate = 0;
@@ -117,6 +123,15 @@ static void __init sun4i_timer_init(struct device_node *node)
 
 	rate = clk_get_rate(clk);
 
+	writel(~0, timer_base + TIMER_INTVAL_REG(1));
+	writel(TIMER_CTL_ENABLE | TIMER_CTL_RELOAD |
+	       TIMER_CTL_CLK_SRC(TIMER_CTL_CLK_SRC_OSC24M),
+	       timer_base + TIMER_CTL_REG(1));
+
+	setup_sched_clock(sun4i_timer_sched_read, 32, rate);
+	clocksource_mmio_init(timer_base + TIMER_CNTVAL_REG(1), node->name,
+			      rate, 300, 32, clocksource_mmio_readl_down);
+
 	writel(rate / (TIMER_SCAL * HZ),
 	       timer_base + TIMER_INTVAL_REG(0));
 

From 8c31bec28b69a86aa83f072e6e00225380853a9e Mon Sep 17 00:00:00 2001
From: Maxime Ripard <maxime.ripard@free-electrons.com>
Date: Tue, 16 Jul 2013 16:45:38 +0200
Subject: [PATCH 07/23] clocksource: sun4i: Don't forget to enable the clock we
 use

Even if in our case, this clock was non-gatable, used as a parent clock
for several IPs, it still is a good idea to enable it.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
---
 drivers/clocksource/sun4i_timer.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/clocksource/sun4i_timer.c b/drivers/clocksource/sun4i_timer.c
index b581c93f20b3..8e9c65136451 100644
--- a/drivers/clocksource/sun4i_timer.c
+++ b/drivers/clocksource/sun4i_timer.c
@@ -120,6 +120,7 @@ static void __init sun4i_timer_init(struct device_node *node)
 	clk = of_clk_get(node, 0);
 	if (IS_ERR(clk))
 		panic("Can't get timer clock");
+	clk_prepare_enable(clk);
 
 	rate = clk_get_rate(clk);
 

From 63d88f1ac71173e47c40ea116e4489f71c6ed9c7 Mon Sep 17 00:00:00 2001
From: Maxime Ripard <maxime.ripard@free-electrons.com>
Date: Tue, 16 Jul 2013 16:45:38 +0200
Subject: [PATCH 08/23] clocksource: sun4i: Fix the next event code

The next_event logic was setting the next interval to fire in the
current timer value instead of the interval value register, which is
obviously wrong.

Plus, the logic to set the actual value was wrong as well: the interval
register can only be modified when the timer is disabled, and then
enable it back, otherwise, it'll have no effect. Fix this logic as well
since that code couldn't possibly work.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
---
 drivers/clocksource/sun4i_timer.c | 25 ++++++++++++++++++++++---
 1 file changed, 22 insertions(+), 3 deletions(-)

diff --git a/drivers/clocksource/sun4i_timer.c b/drivers/clocksource/sun4i_timer.c
index 8e9c65136451..7123f654ce71 100644
--- a/drivers/clocksource/sun4i_timer.c
+++ b/drivers/clocksource/sun4i_timer.c
@@ -38,6 +38,20 @@
 
 static void __iomem *timer_base;
 
+/*
+ * When we disable a timer, we need to wait at least for 2 cycles of
+ * the timer source clock. We will use for that the clocksource timer
+ * that is already setup and runs at the same frequency than the other
+ * timers, and we never will be disabled.
+ */
+static void sun4i_clkevt_sync(void)
+{
+	u32 old = readl(timer_base + TIMER_CNTVAL_REG(1));
+
+	while ((old - readl(timer_base + TIMER_CNTVAL_REG(1))) < 3)
+		cpu_relax();
+}
+
 static void sun4i_clkevt_mode(enum clock_event_mode mode,
 			      struct clock_event_device *clk)
 {
@@ -63,9 +77,14 @@ static void sun4i_clkevt_mode(enum clock_event_mode mode,
 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,
+	u32 val = readl(timer_base + TIMER_CTL_REG(0));
+	writel(val & ~TIMER_CTL_ENABLE, timer_base + TIMER_CTL_REG(0));
+	sun4i_clkevt_sync();
+
+	writel(evt, timer_base + TIMER_INTVAL_REG(0));
+
+	val = readl(timer_base + TIMER_CTL_REG(0));
+	writel(val | TIMER_CTL_ENABLE | TIMER_CTL_AUTORELOAD,
 	       timer_base + TIMER_CTL_REG(0));
 
 	return 0;

From 96651a0732d148f7e4a59cec6aa174049866cd0e Mon Sep 17 00:00:00 2001
From: Maxime Ripard <maxime.ripard@free-electrons.com>
Date: Tue, 16 Jul 2013 16:45:38 +0200
Subject: [PATCH 09/23] clocksource: sun4i: Factor out some timer code

The set_next_event and set_mode callbacks share a lot of common code we
can easily factor to avoid duplication and mistakes.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
---
 drivers/clocksource/sun4i_timer.c | 48 ++++++++++++++++++++-----------
 1 file changed, 32 insertions(+), 16 deletions(-)

diff --git a/drivers/clocksource/sun4i_timer.c b/drivers/clocksource/sun4i_timer.c
index 7123f654ce71..dd78b63f3a24 100644
--- a/drivers/clocksource/sun4i_timer.c
+++ b/drivers/clocksource/sun4i_timer.c
@@ -52,24 +52,46 @@ static void sun4i_clkevt_sync(void)
 		cpu_relax();
 }
 
+static void sun4i_clkevt_time_stop(u8 timer)
+{
+	u32 val = readl(timer_base + TIMER_CTL_REG(timer));
+	writel(val & ~TIMER_CTL_ENABLE, timer_base + TIMER_CTL_REG(timer));
+	sun4i_clkevt_sync();
+}
+
+static void sun4i_clkevt_time_setup(u8 timer, unsigned long delay)
+{
+	writel(delay, timer_base + TIMER_INTVAL_REG(timer));
+}
+
+static void sun4i_clkevt_time_start(u8 timer, bool periodic)
+{
+	u32 val = readl(timer_base + TIMER_CTL_REG(timer));
+
+	if (periodic)
+		val &= ~TIMER_CTL_ONESHOT;
+	else
+		val |= TIMER_CTL_ONESHOT;
+
+	writel(val | TIMER_CTL_ENABLE, timer_base + TIMER_CTL_REG(timer));
+}
+
 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));
+		sun4i_clkevt_time_stop(0);
+		sun4i_clkevt_time_start(0, true);
 		break;
-
 	case CLOCK_EVT_MODE_ONESHOT:
-		writel(u | TIMER_CTL_ONESHOT, timer_base + TIMER_CTL_REG(0));
+		sun4i_clkevt_time_stop(0);
+		sun4i_clkevt_time_start(0, false);
 		break;
 	case CLOCK_EVT_MODE_UNUSED:
 	case CLOCK_EVT_MODE_SHUTDOWN:
 	default:
-		writel(u & ~(TIMER_CTL_ENABLE), timer_base + TIMER_CTL_REG(0));
+		sun4i_clkevt_time_stop(0);
 		break;
 	}
 }
@@ -77,15 +99,9 @@ static void sun4i_clkevt_mode(enum clock_event_mode mode,
 static int sun4i_clkevt_next_event(unsigned long evt,
 				   struct clock_event_device *unused)
 {
-	u32 val = readl(timer_base + TIMER_CTL_REG(0));
-	writel(val & ~TIMER_CTL_ENABLE, timer_base + TIMER_CTL_REG(0));
-	sun4i_clkevt_sync();
-
-	writel(evt, timer_base + TIMER_INTVAL_REG(0));
-
-	val = readl(timer_base + TIMER_CTL_REG(0));
-	writel(val | TIMER_CTL_ENABLE | TIMER_CTL_AUTORELOAD,
-	       timer_base + TIMER_CTL_REG(0));
+	sun4i_clkevt_time_stop(0);
+	sun4i_clkevt_time_setup(0, evt);
+	sun4i_clkevt_time_start(0, false);
 
 	return 0;
 }

From c2b852f77b0d4c71967b61848d666c7a25e17627 Mon Sep 17 00:00:00 2001
From: Maxime Ripard <maxime.ripard@free-electrons.com>
Date: Tue, 16 Jul 2013 16:45:38 +0200
Subject: [PATCH 10/23] clocksource: sun4i: Remove TIMER_SCAL variable

The prescaler is only used when using the internal low frequency
oscillator (at 32kHz). Since we're using the higher frequency oscillator
at 24MHz, we can just remove it.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
---
 drivers/clocksource/sun4i_timer.c | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/drivers/clocksource/sun4i_timer.c b/drivers/clocksource/sun4i_timer.c
index dd78b63f3a24..3217adc7457c 100644
--- a/drivers/clocksource/sun4i_timer.c
+++ b/drivers/clocksource/sun4i_timer.c
@@ -34,8 +34,6 @@
 #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;
 
 /*
@@ -168,8 +166,7 @@ static void __init sun4i_timer_init(struct device_node *node)
 	clocksource_mmio_init(timer_base + TIMER_CNTVAL_REG(1), node->name,
 			      rate, 300, 32, clocksource_mmio_readl_down);
 
-	writel(rate / (TIMER_SCAL * HZ),
-	       timer_base + TIMER_INTVAL_REG(0));
+	writel(rate / HZ, timer_base + TIMER_INTVAL_REG(0));
 
 	/* set clock source to HOSC, 16 pre-division */
 	val = readl(timer_base + TIMER_CTL_REG(0));
@@ -192,8 +189,8 @@ static void __init sun4i_timer_init(struct device_node *node)
 
 	sun4i_clockevent.cpumask = cpumask_of(0);
 
-	clockevents_config_and_register(&sun4i_clockevent, rate / TIMER_SCAL,
-					0x1, 0xff);
+	clockevents_config_and_register(&sun4i_clockevent, rate, 0x1,
+					0xffffffff);
 }
 CLOCKSOURCE_OF_DECLARE(sun4i, "allwinner,sun4i-timer",
 		       sun4i_timer_init);

From a2c49e7b553a28f10ab34e5da538ed4a45a697a7 Mon Sep 17 00:00:00 2001
From: Maxime Ripard <maxime.ripard@free-electrons.com>
Date: Tue, 16 Jul 2013 16:45:38 +0200
Subject: [PATCH 11/23] clocksource: sun4i: Cleanup parent clock setup

The current bring-up code for the timer was overly complicated. The only
thing we need is actually which clock we want to use as source and
that's pretty much all. Let's keep it that way.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
---
 drivers/clocksource/sun4i_timer.c | 15 +++++----------
 1 file changed, 5 insertions(+), 10 deletions(-)

diff --git a/drivers/clocksource/sun4i_timer.c b/drivers/clocksource/sun4i_timer.c
index 3217adc7457c..2fadb3ba59db 100644
--- a/drivers/clocksource/sun4i_timer.c
+++ b/drivers/clocksource/sun4i_timer.c
@@ -30,6 +30,9 @@
 #define TIMER_CTL_REG(val)	(0x10 * val + 0x10)
 #define TIMER_CTL_ENABLE		BIT(0)
 #define TIMER_CTL_RELOAD		BIT(1)
+#define TIMER_CTL_CLK_SRC(val)		(((val) & 0x3) << 2)
+#define TIMER_CTL_CLK_SRC_OSC24M		(1)
+#define TIMER_CTL_CLK_PRES(val)		(((val) & 0x7) << 4)
 #define TIMER_CTL_ONESHOT		BIT(7)
 #define TIMER_INTVAL_REG(val)	(0x10 * (val) + 0x14)
 #define TIMER_CNTVAL_REG(val)	(0x10 * (val) + 0x18)
@@ -168,16 +171,8 @@ static void __init sun4i_timer_init(struct device_node *node)
 
 	writel(rate / 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_RELOAD, timer_base + TIMER_CTL_REG(0));
+	writel(TIMER_CTL_CLK_SRC(TIMER_CTL_CLK_SRC_OSC24M) | TIMER_CTL_RELOAD,
+	       timer_base + TIMER_CTL_REG(0));
 
 	ret = setup_irq(irq, &sun4i_timer_irq);
 	if (ret)

From 7e14183469d8aa2c7aa7675a6156e7846dda7748 Mon Sep 17 00:00:00 2001
From: Maxime Ripard <maxime.ripard@free-electrons.com>
Date: Tue, 16 Jul 2013 16:45:38 +0200
Subject: [PATCH 12/23] clocksource: sun4i: Fix bug when switching from
 periodic to oneshot modes

The interval was firing at was set up at probe time, and only changed in
the set_next_event, and never changed back, which is not really what is
expected.

When enabling the periodic mode, now set an interval to tick every
jiffy.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
---
 drivers/clocksource/sun4i_timer.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/clocksource/sun4i_timer.c b/drivers/clocksource/sun4i_timer.c
index 2fadb3ba59db..8ead0258740a 100644
--- a/drivers/clocksource/sun4i_timer.c
+++ b/drivers/clocksource/sun4i_timer.c
@@ -38,6 +38,7 @@
 #define TIMER_CNTVAL_REG(val)	(0x10 * (val) + 0x18)
 
 static void __iomem *timer_base;
+static u32 ticks_per_jiffy;
 
 /*
  * When we disable a timer, we need to wait at least for 2 cycles of
@@ -74,7 +75,8 @@ static void sun4i_clkevt_time_start(u8 timer, bool periodic)
 	else
 		val |= TIMER_CTL_ONESHOT;
 
-	writel(val | TIMER_CTL_ENABLE, timer_base + TIMER_CTL_REG(timer));
+	writel(val | TIMER_CTL_ENABLE | TIMER_CTL_RELOAD,
+	       timer_base + TIMER_CTL_REG(timer));
 }
 
 static void sun4i_clkevt_mode(enum clock_event_mode mode,
@@ -83,6 +85,7 @@ static void sun4i_clkevt_mode(enum clock_event_mode mode,
 	switch (mode) {
 	case CLOCK_EVT_MODE_PERIODIC:
 		sun4i_clkevt_time_stop(0);
+		sun4i_clkevt_time_setup(0, ticks_per_jiffy);
 		sun4i_clkevt_time_start(0, true);
 		break;
 	case CLOCK_EVT_MODE_ONESHOT:
@@ -169,9 +172,9 @@ static void __init sun4i_timer_init(struct device_node *node)
 	clocksource_mmio_init(timer_base + TIMER_CNTVAL_REG(1), node->name,
 			      rate, 300, 32, clocksource_mmio_readl_down);
 
-	writel(rate / HZ, timer_base + TIMER_INTVAL_REG(0));
+	ticks_per_jiffy = DIV_ROUND_UP(rate, HZ);
 
-	writel(TIMER_CTL_CLK_SRC(TIMER_CTL_CLK_SRC_OSC24M) | TIMER_CTL_RELOAD,
+	writel(TIMER_CTL_CLK_SRC(TIMER_CTL_CLK_SRC_OSC24M),
 	       timer_base + TIMER_CTL_REG(0));
 
 	ret = setup_irq(irq, &sun4i_timer_irq);

From 9bbf914043e04f65e619f3c0ff67c387812f9458 Mon Sep 17 00:00:00 2001
From: Soren Brinkmann <soren.brinkmann@xilinx.com>
Date: Mon, 8 Jul 2013 09:51:37 -0700
Subject: [PATCH 13/23] clocksource: cadence_ttc: Remove unused header

The clk-provider.h header is not required by this driver.

Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
---
 drivers/clocksource/cadence_ttc_timer.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/clocksource/cadence_ttc_timer.c b/drivers/clocksource/cadence_ttc_timer.c
index 4cbe28c74631..0eefc8d8622b 100644
--- a/drivers/clocksource/cadence_ttc_timer.c
+++ b/drivers/clocksource/cadence_ttc_timer.c
@@ -21,7 +21,6 @@
 #include <linux/of_address.h>
 #include <linux/of_irq.h>
 #include <linux/slab.h>
-#include <linux/clk-provider.h>
 
 /*
  * This driver configures the 2 16-bit count-up timers as follows:

From 3d77b30efc72d126c2b74070b41a03869611228d Mon Sep 17 00:00:00 2001
From: Soren Brinkmann <soren.brinkmann@xilinx.com>
Date: Mon, 8 Jul 2013 09:51:38 -0700
Subject: [PATCH 14/23] clocksource: cadence_ttc: Reuse clocksource as
 sched_clock

Reuse the TTC clocksource timer as sched clock provider.

Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Michal Simek <monstr@monstr.eu>
---
 drivers/clocksource/cadence_ttc_timer.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/drivers/clocksource/cadence_ttc_timer.c b/drivers/clocksource/cadence_ttc_timer.c
index 0eefc8d8622b..b2bb3a4bc205 100644
--- a/drivers/clocksource/cadence_ttc_timer.c
+++ b/drivers/clocksource/cadence_ttc_timer.c
@@ -21,6 +21,7 @@
 #include <linux/of_address.h>
 #include <linux/of_irq.h>
 #include <linux/slab.h>
+#include <linux/sched_clock.h>
 
 /*
  * This driver configures the 2 16-bit count-up timers as follows:
@@ -94,6 +95,8 @@ struct ttc_timer_clockevent {
 #define to_ttc_timer_clkevent(x) \
 		container_of(x, struct ttc_timer_clockevent, ce)
 
+static void __iomem *ttc_sched_clock_val_reg;
+
 /**
  * ttc_set_interval - Set the timer interval value
  *
@@ -155,6 +158,11 @@ static cycle_t __ttc_clocksource_read(struct clocksource *cs)
 				TTC_COUNT_VAL_OFFSET);
 }
 
+static u32 notrace ttc_sched_clock_read(void)
+{
+	return __raw_readl(ttc_sched_clock_val_reg);
+}
+
 /**
  * ttc_set_next_event - Sets the time interval for next event
  *
@@ -296,6 +304,10 @@ static void __init ttc_setup_clocksource(struct clk *clk, void __iomem *base)
 		kfree(ttccs);
 		return;
 	}
+
+	ttc_sched_clock_val_reg = base + TTC_COUNT_VAL_OFFSET;
+	setup_sched_clock(ttc_sched_clock_read, 16,
+			clk_get_rate(ttccs->ttc.clk) / PRESCALE);
 }
 
 static int ttc_rate_change_clockevent_cb(struct notifier_block *nb,

From 07862c1cd6675cde2dd4bd64e64d704ea2185b79 Mon Sep 17 00:00:00 2001
From: Jonas Jensen <jonas.jensen@gmail.com>
Date: Wed, 17 Jul 2013 10:04:57 +0200
Subject: [PATCH 15/23] ARM: clocksource: Add support for MOXA ART SoCs

This patch adds an clocksource driver for the main timer(s)
found on MOXA ART SoCs.

The MOXA ART SoC provides three separate timers with individual
count/load/match registers, two are used here:

TIMER1: clockevents, used to support oneshot and periodic events
TIMER2: set up as a free running counter, used as clocksource

Timers are preconfigured by bootloader to count down and interrupt
on match or zero. Count increments every APB clock cycle and is
automatically reloaded when it reaches zero.

Signed-off-by: Jonas Jensen <jonas.jensen@gmail.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
---
 .../bindings/timer/moxa,moxart-timer.txt      |  17 ++
 drivers/clocksource/Makefile                  |   1 +
 drivers/clocksource/moxart_timer.c            | 164 ++++++++++++++++++
 3 files changed, 182 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/timer/moxa,moxart-timer.txt
 create mode 100644 drivers/clocksource/moxart_timer.c

diff --git a/Documentation/devicetree/bindings/timer/moxa,moxart-timer.txt b/Documentation/devicetree/bindings/timer/moxa,moxart-timer.txt
new file mode 100644
index 000000000000..77c4cfa198ee
--- /dev/null
+++ b/Documentation/devicetree/bindings/timer/moxa,moxart-timer.txt
@@ -0,0 +1,17 @@
+MOXA ART timer
+
+Required properties:
+
+- compatible : Should be "moxa,moxart-timer"
+- reg : Should contain registers location and length
+- interrupts : Should contain the timer interrupt number
+- clocks : Should contain phandle for APB clock "clkapb"
+
+Example:
+
+	timer: timer@98400000 {
+		compatible = "moxa,moxart-timer";
+		reg = <0x98400000 0x42>;
+		interrupts = <19 1>;
+		clocks = <&clkapb>;
+	};
diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index 8b00c5cebfa4..704d6d342adc 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -18,6 +18,7 @@ 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_MARCO)	+= timer-marco.o
+obj-$(CONFIG_ARCH_MOXART)	+= moxart_timer.o
 obj-$(CONFIG_ARCH_MXS)		+= mxs_timer.o
 obj-$(CONFIG_ARCH_PRIMA2)	+= timer-prima2.o
 obj-$(CONFIG_SUN4I_TIMER)	+= sun4i_timer.o
diff --git a/drivers/clocksource/moxart_timer.c b/drivers/clocksource/moxart_timer.c
new file mode 100644
index 000000000000..08a5943b3e42
--- /dev/null
+++ b/drivers/clocksource/moxart_timer.c
@@ -0,0 +1,164 @@
+/*
+ * MOXA ART SoCs timer handling.
+ *
+ * Copyright (C) 2013 Jonas Jensen
+ *
+ * Jonas Jensen <jonas.jensen@gmail.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>
+#include <linux/io.h>
+#include <linux/clocksource.h>
+
+#define TIMER1_BASE		0x00
+#define TIMER2_BASE		0x10
+#define TIMER3_BASE		0x20
+
+#define REG_COUNT		0x0 /* writable */
+#define REG_LOAD		0x4
+#define REG_MATCH1		0x8
+#define REG_MATCH2		0xC
+
+#define TIMER_CR		0x30
+#define TIMER_INTR_STATE	0x34
+#define TIMER_INTR_MASK		0x38
+
+/*
+ * TIMER_CR flags:
+ *
+ * TIMEREG_CR_*_CLOCK	0: PCLK, 1: EXT1CLK
+ * TIMEREG_CR_*_INT	overflow interrupt enable bit
+ */
+#define TIMEREG_CR_1_ENABLE	BIT(0)
+#define TIMEREG_CR_1_CLOCK	BIT(1)
+#define TIMEREG_CR_1_INT	BIT(2)
+#define TIMEREG_CR_2_ENABLE	BIT(3)
+#define TIMEREG_CR_2_CLOCK	BIT(4)
+#define TIMEREG_CR_2_INT	BIT(5)
+#define TIMEREG_CR_3_ENABLE	BIT(6)
+#define TIMEREG_CR_3_CLOCK	BIT(7)
+#define TIMEREG_CR_3_INT	BIT(8)
+#define TIMEREG_CR_COUNT_UP	BIT(9)
+
+#define TIMER1_ENABLE		(TIMEREG_CR_2_ENABLE | TIMEREG_CR_1_ENABLE)
+#define TIMER1_DISABLE		(TIMEREG_CR_2_ENABLE)
+
+static void __iomem *base;
+static unsigned int clock_count_per_tick;
+
+static void moxart_clkevt_mode(enum clock_event_mode mode,
+			       struct clock_event_device *clk)
+{
+	switch (mode) {
+	case CLOCK_EVT_MODE_RESUME:
+	case CLOCK_EVT_MODE_ONESHOT:
+		writel(TIMER1_DISABLE, base + TIMER_CR);
+		writel(~0, base + TIMER1_BASE + REG_LOAD);
+		break;
+	case CLOCK_EVT_MODE_PERIODIC:
+		writel(clock_count_per_tick, base + TIMER1_BASE + REG_LOAD);
+		writel(TIMER1_ENABLE, base + TIMER_CR);
+		break;
+	case CLOCK_EVT_MODE_UNUSED:
+	case CLOCK_EVT_MODE_SHUTDOWN:
+	default:
+		writel(TIMER1_DISABLE, base + TIMER_CR);
+		break;
+	}
+}
+
+static int moxart_clkevt_next_event(unsigned long cycles,
+				    struct clock_event_device *unused)
+{
+	u32 u;
+
+	writel(TIMER1_DISABLE, base + TIMER_CR);
+
+	u = readl(base + TIMER1_BASE + REG_COUNT) - cycles;
+	writel(u, base + TIMER1_BASE + REG_MATCH1);
+
+	writel(TIMER1_ENABLE, base + TIMER_CR);
+
+	return 0;
+}
+
+static struct clock_event_device moxart_clockevent = {
+	.name		= "moxart_timer",
+	.rating		= 200,
+	.features	= CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
+	.set_mode	= moxart_clkevt_mode,
+	.set_next_event	= moxart_clkevt_next_event,
+};
+
+static irqreturn_t moxart_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = dev_id;
+	evt->event_handler(evt);
+	return IRQ_HANDLED;
+}
+
+static struct irqaction moxart_timer_irq = {
+	.name		= "moxart-timer",
+	.flags		= IRQF_TIMER,
+	.handler	= moxart_timer_interrupt,
+	.dev_id		= &moxart_clockevent,
+};
+
+static void __init moxart_timer_init(struct device_node *node)
+{
+	int ret, irq;
+	unsigned long pclk;
+	struct clk *clk;
+
+	base = of_iomap(node, 0);
+	if (!base)
+		panic("%s: of_iomap failed\n", node->full_name);
+
+	irq = irq_of_parse_and_map(node, 0);
+	if (irq <= 0)
+		panic("%s: irq_of_parse_and_map failed\n", node->full_name);
+
+	ret = setup_irq(irq, &moxart_timer_irq);
+	if (ret)
+		panic("%s: setup_irq failed\n", node->full_name);
+
+	clk = of_clk_get(node, 0);
+	if (IS_ERR(clk))
+		panic("%s: of_clk_get failed\n", node->full_name);
+
+	pclk = clk_get_rate(clk);
+
+	if (clocksource_mmio_init(base + TIMER2_BASE + REG_COUNT,
+				  "moxart_timer", pclk, 200, 32,
+				  clocksource_mmio_readl_down))
+		panic("%s: clocksource_mmio_init failed\n", node->full_name);
+
+	clock_count_per_tick = DIV_ROUND_CLOSEST(pclk, HZ);
+
+	writel(~0, base + TIMER2_BASE + REG_LOAD);
+	writel(TIMEREG_CR_2_ENABLE, base + TIMER_CR);
+
+	moxart_clockevent.cpumask = cpumask_of(0);
+	moxart_clockevent.irq = irq;
+
+	/*
+	 * documentation is not publicly available:
+	 * min_delta / max_delta obtained by trial-and-error,
+	 * max_delta 0xfffffffe should be ok because count
+	 * register size is u32
+	 */
+	clockevents_config_and_register(&moxart_clockevent, pclk,
+					0x4, 0xfffffffe);
+}
+CLOCKSOURCE_OF_DECLARE(moxart, "moxa,moxart-timer", moxart_timer_init);

From b662a8662436cd4815e1738d5f491a12dc289177 Mon Sep 17 00:00:00 2001
From: Jonas Jensen <jonas.jensen@gmail.com>
Date: Fri, 19 Jul 2013 13:12:59 +0200
Subject: [PATCH 16/23] ARM: clocksource: moxart: documentation: Fix device
 tree bindings document

Fix device tree bindings document with the correct clock name.

Signed-off-by: Jonas Jensen <jonas.jensen@gmail.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
---
 Documentation/devicetree/bindings/timer/moxa,moxart-timer.txt | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/timer/moxa,moxart-timer.txt b/Documentation/devicetree/bindings/timer/moxa,moxart-timer.txt
index 77c4cfa198ee..ad0bf7f1a7e7 100644
--- a/Documentation/devicetree/bindings/timer/moxa,moxart-timer.txt
+++ b/Documentation/devicetree/bindings/timer/moxa,moxart-timer.txt
@@ -5,7 +5,7 @@ Required properties:
 - compatible : Should be "moxa,moxart-timer"
 - reg : Should contain registers location and length
 - interrupts : Should contain the timer interrupt number
-- clocks : Should contain phandle for APB clock "clkapb"
+- clocks : Should contain phandle for the MOXA ART core clock "coreclk"
 
 Example:
 
@@ -13,5 +13,5 @@ Example:
 		compatible = "moxa,moxart-timer";
 		reg = <0x98400000 0x42>;
 		interrupts = <19 1>;
-		clocks = <&clkapb>;
+		clocks = <&coreclk>;
 	};

From adf157ebf6097aa2abc7f05120e7dda6ed238252 Mon Sep 17 00:00:00 2001
From: Jonas Jensen <jonas.jensen@gmail.com>
Date: Fri, 26 Jul 2013 16:03:38 +0200
Subject: [PATCH 17/23] ARM: clocksource: moxart: Add bitops.h include

bitops.h included implicitly, add #include <linux/bitops.h>

Signed-off-by: Jonas Jensen <jonas.jensen@gmail.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
---
 drivers/clocksource/moxart_timer.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/clocksource/moxart_timer.c b/drivers/clocksource/moxart_timer.c
index 08a5943b3e42..5eb2c35932b1 100644
--- a/drivers/clocksource/moxart_timer.c
+++ b/drivers/clocksource/moxart_timer.c
@@ -20,6 +20,7 @@
 #include <linux/of_irq.h>
 #include <linux/io.h>
 #include <linux/clocksource.h>
+#include <linux/bitops.h>
 
 #define TIMER1_BASE		0x00
 #define TIMER2_BASE		0x10

From 766acb88a773dcbc98f2ae8d7ef8c147e2dccd99 Mon Sep 17 00:00:00 2001
From: Jonas Jensen <jonas.jensen@gmail.com>
Date: Fri, 26 Jul 2013 16:17:15 +0200
Subject: [PATCH 18/23] ARM: clocksource: moxart: documentation: Update device
 tree bindings document

1. describe compatible variable "Must be" instead of "Should be".
2. change description so it's from the point of view of the device

Signed-off-by: Jonas Jensen <jonas.jensen@gmail.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
---
 Documentation/devicetree/bindings/timer/moxa,moxart-timer.txt | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/timer/moxa,moxart-timer.txt b/Documentation/devicetree/bindings/timer/moxa,moxart-timer.txt
index ad0bf7f1a7e7..da2d510cae47 100644
--- a/Documentation/devicetree/bindings/timer/moxa,moxart-timer.txt
+++ b/Documentation/devicetree/bindings/timer/moxa,moxart-timer.txt
@@ -2,10 +2,10 @@ MOXA ART timer
 
 Required properties:
 
-- compatible : Should be "moxa,moxart-timer"
+- compatible : Must be "moxa,moxart-timer"
 - reg : Should contain registers location and length
 - interrupts : Should contain the timer interrupt number
-- clocks : Should contain phandle for the MOXA ART core clock "coreclk"
+- clocks : Should contain phandle for the clock that drives the counter
 
 Example:
 

From e09f3cc0184d6b5c3816f921b7ffb67623e5e834 Mon Sep 17 00:00:00 2001
From: Stephen Boyd <sboyd@codeaurora.org>
Date: Thu, 18 Jul 2013 16:59:28 -0700
Subject: [PATCH 19/23] clocksource: arch_timer: Make register accessors less
 error-prone

Using an enum for the register we wish to access allows newer
compilers to determine if we've forgotten a case in our switch
statement. This allows us to remove the BUILD_BUG() instances in
the arm64 port, avoiding problems where optimizations may not
happen.

To try and force better code generation we're currently marking
the accessor functions as inline, but newer compilers can ignore
the inline keyword unless it's marked __always_inline. Luckily on
arm and arm64 inline is __always_inline, but let's make
everything __always_inline to be explicit.

Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Marc Zyngier <Marc.Zyngier@arm.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
---
 arch/arm/include/asm/arch_timer.h    | 14 ++++++--------
 arch/arm64/include/asm/arch_timer.h  | 23 +++++++++--------------
 drivers/clocksource/arm_arch_timer.c |  6 +++---
 include/clocksource/arm_arch_timer.h |  6 ++++--
 4 files changed, 22 insertions(+), 27 deletions(-)

diff --git a/arch/arm/include/asm/arch_timer.h b/arch/arm/include/asm/arch_timer.h
index accefe099182..aeb93f38e9c9 100644
--- a/arch/arm/include/asm/arch_timer.h
+++ b/arch/arm/include/asm/arch_timer.h
@@ -17,7 +17,8 @@ int arch_timer_arch_init(void);
  * nicely work out which register we want, and chuck away the rest of
  * the code. At least it does so with a recent GCC (4.6.3).
  */
-static inline void arch_timer_reg_write(const int access, const int reg, u32 val)
+static __always_inline
+void arch_timer_reg_write(int access, enum arch_timer_reg reg, u32 val)
 {
 	if (access == ARCH_TIMER_PHYS_ACCESS) {
 		switch (reg) {
@@ -28,9 +29,7 @@ static inline void arch_timer_reg_write(const int access, const int reg, u32 val
 			asm volatile("mcr p15, 0, %0, c14, c2, 0" : : "r" (val));
 			break;
 		}
-	}
-
-	if (access == ARCH_TIMER_VIRT_ACCESS) {
+	} else if (access == ARCH_TIMER_VIRT_ACCESS) {
 		switch (reg) {
 		case ARCH_TIMER_REG_CTRL:
 			asm volatile("mcr p15, 0, %0, c14, c3, 1" : : "r" (val));
@@ -44,7 +43,8 @@ static inline void arch_timer_reg_write(const int access, const int reg, u32 val
 	isb();
 }
 
-static inline u32 arch_timer_reg_read(const int access, const int reg)
+static __always_inline
+u32 arch_timer_reg_read(int access, enum arch_timer_reg reg)
 {
 	u32 val = 0;
 
@@ -57,9 +57,7 @@ static inline u32 arch_timer_reg_read(const int access, const int reg)
 			asm volatile("mrc p15, 0, %0, c14, c2, 0" : "=r" (val));
 			break;
 		}
-	}
-
-	if (access == ARCH_TIMER_VIRT_ACCESS) {
+	} else if (access == ARCH_TIMER_VIRT_ACCESS) {
 		switch (reg) {
 		case ARCH_TIMER_REG_CTRL:
 			asm volatile("mrc p15, 0, %0, c14, c3, 1" : "=r" (val));
diff --git a/arch/arm64/include/asm/arch_timer.h b/arch/arm64/include/asm/arch_timer.h
index d56ed11ba9a3..dbca77168e81 100644
--- a/arch/arm64/include/asm/arch_timer.h
+++ b/arch/arm64/include/asm/arch_timer.h
@@ -26,7 +26,13 @@
 
 #include <clocksource/arm_arch_timer.h>
 
-static inline void arch_timer_reg_write(int access, int reg, u32 val)
+/*
+ * These register accessors are marked inline so the compiler can
+ * nicely work out which register we want, and chuck away the rest of
+ * the code.
+ */
+static __always_inline
+void arch_timer_reg_write(int access, enum arch_timer_reg reg, u32 val)
 {
 	if (access == ARCH_TIMER_PHYS_ACCESS) {
 		switch (reg) {
@@ -36,8 +42,6 @@ static inline void arch_timer_reg_write(int access, int reg, u32 val)
 		case ARCH_TIMER_REG_TVAL:
 			asm volatile("msr cntp_tval_el0, %0" : : "r" (val));
 			break;
-		default:
-			BUILD_BUG();
 		}
 	} else if (access == ARCH_TIMER_VIRT_ACCESS) {
 		switch (reg) {
@@ -47,17 +51,14 @@ static inline void arch_timer_reg_write(int access, int reg, u32 val)
 		case ARCH_TIMER_REG_TVAL:
 			asm volatile("msr cntv_tval_el0, %0" : : "r" (val));
 			break;
-		default:
-			BUILD_BUG();
 		}
-	} else {
-		BUILD_BUG();
 	}
 
 	isb();
 }
 
-static inline u32 arch_timer_reg_read(int access, int reg)
+static __always_inline
+u32 arch_timer_reg_read(int access, enum arch_timer_reg reg)
 {
 	u32 val;
 
@@ -69,8 +70,6 @@ static inline u32 arch_timer_reg_read(int access, int reg)
 		case ARCH_TIMER_REG_TVAL:
 			asm volatile("mrs %0, cntp_tval_el0" : "=r" (val));
 			break;
-		default:
-			BUILD_BUG();
 		}
 	} else if (access == ARCH_TIMER_VIRT_ACCESS) {
 		switch (reg) {
@@ -80,11 +79,7 @@ static inline u32 arch_timer_reg_read(int access, int reg)
 		case ARCH_TIMER_REG_TVAL:
 			asm volatile("mrs %0, cntv_tval_el0" : "=r" (val));
 			break;
-		default:
-			BUILD_BUG();
 		}
-	} else {
-		BUILD_BUG();
 	}
 
 	return val;
diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index 053d846ab5b1..aa0703847e5d 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -43,7 +43,7 @@ static bool arch_timer_use_virtual = true;
  * Architected system timer support.
  */
 
-static inline irqreturn_t timer_handler(const int access,
+static __always_inline irqreturn_t timer_handler(const int access,
 					struct clock_event_device *evt)
 {
 	unsigned long ctrl;
@@ -72,7 +72,7 @@ static irqreturn_t arch_timer_handler_phys(int irq, void *dev_id)
 	return timer_handler(ARCH_TIMER_PHYS_ACCESS, evt);
 }
 
-static inline void timer_set_mode(const int access, int mode)
+static __always_inline void timer_set_mode(const int access, int mode)
 {
 	unsigned long ctrl;
 	switch (mode) {
@@ -99,7 +99,7 @@ static void arch_timer_set_mode_phys(enum clock_event_mode mode,
 	timer_set_mode(ARCH_TIMER_PHYS_ACCESS, mode);
 }
 
-static inline void set_next_event(const int access, unsigned long evt)
+static __always_inline void set_next_event(const int access, unsigned long evt)
 {
 	unsigned long ctrl;
 	ctrl = arch_timer_reg_read(access, ARCH_TIMER_REG_CTRL);
diff --git a/include/clocksource/arm_arch_timer.h b/include/clocksource/arm_arch_timer.h
index c463ce990c48..f3da817b9b8e 100644
--- a/include/clocksource/arm_arch_timer.h
+++ b/include/clocksource/arm_arch_timer.h
@@ -23,8 +23,10 @@
 #define ARCH_TIMER_CTRL_IT_MASK		(1 << 1)
 #define ARCH_TIMER_CTRL_IT_STAT		(1 << 2)
 
-#define ARCH_TIMER_REG_CTRL		0
-#define ARCH_TIMER_REG_TVAL		1
+enum arch_timer_reg {
+	ARCH_TIMER_REG_CTRL,
+	ARCH_TIMER_REG_TVAL,
+};
 
 #define ARCH_TIMER_PHYS_ACCESS		0
 #define ARCH_TIMER_VIRT_ACCESS		1

From 1ff99ea65687d921cb71f330491ec4205c00eb9f Mon Sep 17 00:00:00 2001
From: Stephen Boyd <sboyd@codeaurora.org>
Date: Thu, 18 Jul 2013 16:59:30 -0700
Subject: [PATCH 20/23] clocksource: arch_timer: Pass clock event to set_mode
 callback

There isn't any reason why we don't pass the event here and we'll
need it in the near future for memory mapped arch timers anyway.

Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Marc Zyngier <Marc.Zyngier@arm.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
---
 drivers/clocksource/arm_arch_timer.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index aa0703847e5d..7624ba574144 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -140,7 +140,7 @@ static int __cpuinit arch_timer_setup(struct clock_event_device *clk)
 
 	clk->cpumask = cpumask_of(smp_processor_id());
 
-	clk->set_mode(CLOCK_EVT_MODE_SHUTDOWN, NULL);
+	clk->set_mode(CLOCK_EVT_MODE_SHUTDOWN, clk);
 
 	clockevents_config_and_register(clk, arch_timer_rate,
 					0xf, 0x7fffffff);

From d53ef114cf40a043e3cc3fa70dbcdfb268a7e4dc Mon Sep 17 00:00:00 2001
From: Stephen Boyd <sboyd@codeaurora.org>
Date: Thu, 18 Jul 2013 16:59:29 -0700
Subject: [PATCH 21/23] Documentation: Add memory mapped ARM architected timer
 binding

Add a binding for the arm architected timer hardware's memory
mapped interface. The mmio timer hardware is made up of one base
frame and a collection of up to 8 timer frames, where each of the
8 timer frames can have either one or two views. A frame
typically maps to a privilege level (user/kernel, hypervisor,
secure). The first view has full access to the registers within a
frame, while the second view can be restricted to particular
registers within a frame. Each frame must support a physical
timer. It's optional for a frame to support a virtual timer.

Cc: devicetree-discuss@lists.ozlabs.org
Cc: Marc Zyngier <Marc.Zyngier@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Rob Herring <robherring2@gmail.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
---
 .../devicetree/bindings/arm/arch_timer.txt    | 59 ++++++++++++++++++-
 1 file changed, 56 insertions(+), 3 deletions(-)

diff --git a/Documentation/devicetree/bindings/arm/arch_timer.txt b/Documentation/devicetree/bindings/arm/arch_timer.txt
index 20746e5abe6f..06fc7602593a 100644
--- a/Documentation/devicetree/bindings/arm/arch_timer.txt
+++ b/Documentation/devicetree/bindings/arm/arch_timer.txt
@@ -1,10 +1,14 @@
 * ARM architected timer
 
-ARM cores may have a per-core architected timer, which provides per-cpu timers.
+ARM cores may have a per-core architected timer, which provides per-cpu timers,
+or a memory mapped architected timer, which provides up to 8 frames with a
+physical and optional virtual timer per frame.
 
-The timer is attached to a GIC to deliver its per-processor interrupts.
+The per-core architected timer is attached to a GIC to deliver its
+per-processor interrupts via PPIs. The memory mapped timer is attached to a GIC
+to deliver its interrupts via SPIs.
 
-** Timer node properties:
+** CP15 Timer node properties:
 
 - compatible : Should at least contain one of
 	"arm,armv7-timer"
@@ -26,3 +30,52 @@ Example:
 			     <1 10 0xf08>;
 		clock-frequency = <100000000>;
 	};
+
+** Memory mapped timer node properties:
+
+- compatible : Should at least contain "arm,armv7-timer-mem".
+
+- clock-frequency : The frequency of the main counter, in Hz. Optional.
+
+- reg : The control frame base address.
+
+Note that #address-cells, #size-cells, and ranges shall be present to ensure
+the CPU can address a frame's registers.
+
+A timer node has up to 8 frame sub-nodes, each with the following properties:
+
+- frame-number: 0 to 7.
+
+- interrupts : Interrupt list for physical and virtual timers in that order.
+  The virtual timer interrupt is optional.
+
+- reg : The first and second view base addresses in that order. The second view
+  base address is optional.
+
+- status : "disabled" indicates the frame is not available for use. Optional.
+
+Example:
+
+	timer@f0000000 {
+		compatible = "arm,armv7-timer-mem";
+		#address-cells = <1>;
+		#size-cells = <1>;
+		ranges;
+		reg = <0xf0000000 0x1000>;
+		clock-frequency = <50000000>;
+
+		frame@f0001000 {
+			frame-number = <0>
+			interrupts = <0 13 0x8>,
+				     <0 14 0x8>;
+			reg = <0xf0001000 0x1000>,
+			      <0xf0002000 0x1000>;
+		};
+
+		frame@f0003000 {
+			frame-number = <1>
+			interrupts = <0 15 0x8>;
+			reg = <0xf0003000 0x1000>;
+			status = "disabled";
+		};
+	};

From 60faddf6eb3aba16068032bdcf35e18ace4bfb21 Mon Sep 17 00:00:00 2001
From: Stephen Boyd <sboyd@codeaurora.org>
Date: Thu, 18 Jul 2013 16:59:31 -0700
Subject: [PATCH 22/23] clocksource: arch_timer: Push the read/write wrappers
 deeper

We're going to introduce support to read and write the memory
mapped timer registers in the next patch, so push the cp15
read/write functions one level deeper. This simplifies the next
patch and makes it clearer what's going on.

Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Marc Zyngier <Marc.Zyngier@arm.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
---
 arch/arm/include/asm/arch_timer.h    |  4 +--
 arch/arm64/include/asm/arch_timer.h  |  4 +--
 drivers/clocksource/arm_arch_timer.c | 46 +++++++++++++++++++---------
 3 files changed, 35 insertions(+), 19 deletions(-)

diff --git a/arch/arm/include/asm/arch_timer.h b/arch/arm/include/asm/arch_timer.h
index aeb93f38e9c9..556094689724 100644
--- a/arch/arm/include/asm/arch_timer.h
+++ b/arch/arm/include/asm/arch_timer.h
@@ -18,7 +18,7 @@ int arch_timer_arch_init(void);
  * the code. At least it does so with a recent GCC (4.6.3).
  */
 static __always_inline
-void arch_timer_reg_write(int access, enum arch_timer_reg reg, u32 val)
+void arch_timer_reg_write_cp15(int access, enum arch_timer_reg reg, u32 val)
 {
 	if (access == ARCH_TIMER_PHYS_ACCESS) {
 		switch (reg) {
@@ -44,7 +44,7 @@ void arch_timer_reg_write(int access, enum arch_timer_reg reg, u32 val)
 }
 
 static __always_inline
-u32 arch_timer_reg_read(int access, enum arch_timer_reg reg)
+u32 arch_timer_reg_read_cp15(int access, enum arch_timer_reg reg)
 {
 	u32 val = 0;
 
diff --git a/arch/arm64/include/asm/arch_timer.h b/arch/arm64/include/asm/arch_timer.h
index dbca77168e81..7181e777c2c5 100644
--- a/arch/arm64/include/asm/arch_timer.h
+++ b/arch/arm64/include/asm/arch_timer.h
@@ -32,7 +32,7 @@
  * the code.
  */
 static __always_inline
-void arch_timer_reg_write(int access, enum arch_timer_reg reg, u32 val)
+void arch_timer_reg_write_cp15(int access, enum arch_timer_reg reg, u32 val)
 {
 	if (access == ARCH_TIMER_PHYS_ACCESS) {
 		switch (reg) {
@@ -58,7 +58,7 @@ void arch_timer_reg_write(int access, enum arch_timer_reg reg, u32 val)
 }
 
 static __always_inline
-u32 arch_timer_reg_read(int access, enum arch_timer_reg reg)
+u32 arch_timer_reg_read_cp15(int access, enum arch_timer_reg reg)
 {
 	u32 val;
 
diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index 7624ba574144..a9ca28447b49 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -43,14 +43,28 @@ static bool arch_timer_use_virtual = true;
  * Architected system timer support.
  */
 
+static __always_inline
+void arch_timer_reg_write(int access, enum arch_timer_reg reg, u32 val,
+		struct clock_event_device *clk)
+{
+	arch_timer_reg_write_cp15(access, reg, val);
+}
+
+static __always_inline
+u32 arch_timer_reg_read(int access, enum arch_timer_reg reg,
+		struct clock_event_device *clk)
+{
+	return arch_timer_reg_read_cp15(access, reg);
+}
+
 static __always_inline irqreturn_t timer_handler(const int access,
 					struct clock_event_device *evt)
 {
 	unsigned long ctrl;
-	ctrl = arch_timer_reg_read(access, ARCH_TIMER_REG_CTRL);
+	ctrl = arch_timer_reg_read(access, ARCH_TIMER_REG_CTRL, evt);
 	if (ctrl & ARCH_TIMER_CTRL_IT_STAT) {
 		ctrl |= ARCH_TIMER_CTRL_IT_MASK;
-		arch_timer_reg_write(access, ARCH_TIMER_REG_CTRL, ctrl);
+		arch_timer_reg_write(access, ARCH_TIMER_REG_CTRL, ctrl, evt);
 		evt->event_handler(evt);
 		return IRQ_HANDLED;
 	}
@@ -72,15 +86,16 @@ static irqreturn_t arch_timer_handler_phys(int irq, void *dev_id)
 	return timer_handler(ARCH_TIMER_PHYS_ACCESS, evt);
 }
 
-static __always_inline void timer_set_mode(const int access, int mode)
+static __always_inline void timer_set_mode(const int access, int mode,
+				  struct clock_event_device *clk)
 {
 	unsigned long ctrl;
 	switch (mode) {
 	case CLOCK_EVT_MODE_UNUSED:
 	case CLOCK_EVT_MODE_SHUTDOWN:
-		ctrl = arch_timer_reg_read(access, ARCH_TIMER_REG_CTRL);
+		ctrl = arch_timer_reg_read(access, ARCH_TIMER_REG_CTRL, clk);
 		ctrl &= ~ARCH_TIMER_CTRL_ENABLE;
-		arch_timer_reg_write(access, ARCH_TIMER_REG_CTRL, ctrl);
+		arch_timer_reg_write(access, ARCH_TIMER_REG_CTRL, ctrl, clk);
 		break;
 	default:
 		break;
@@ -90,36 +105,37 @@ static __always_inline void timer_set_mode(const int access, int mode)
 static void arch_timer_set_mode_virt(enum clock_event_mode mode,
 				     struct clock_event_device *clk)
 {
-	timer_set_mode(ARCH_TIMER_VIRT_ACCESS, mode);
+	timer_set_mode(ARCH_TIMER_VIRT_ACCESS, mode, clk);
 }
 
 static void arch_timer_set_mode_phys(enum clock_event_mode mode,
 				     struct clock_event_device *clk)
 {
-	timer_set_mode(ARCH_TIMER_PHYS_ACCESS, mode);
+	timer_set_mode(ARCH_TIMER_PHYS_ACCESS, mode, clk);
 }
 
-static __always_inline void set_next_event(const int access, unsigned long evt)
+static __always_inline void set_next_event(const int access, unsigned long evt,
+				  struct clock_event_device *clk)
 {
 	unsigned long ctrl;
-	ctrl = arch_timer_reg_read(access, ARCH_TIMER_REG_CTRL);
+	ctrl = arch_timer_reg_read(access, ARCH_TIMER_REG_CTRL, clk);
 	ctrl |= ARCH_TIMER_CTRL_ENABLE;
 	ctrl &= ~ARCH_TIMER_CTRL_IT_MASK;
-	arch_timer_reg_write(access, ARCH_TIMER_REG_TVAL, evt);
-	arch_timer_reg_write(access, ARCH_TIMER_REG_CTRL, ctrl);
+	arch_timer_reg_write(access, ARCH_TIMER_REG_TVAL, evt, clk);
+	arch_timer_reg_write(access, ARCH_TIMER_REG_CTRL, ctrl, clk);
 }
 
 static int arch_timer_set_next_event_virt(unsigned long evt,
-					  struct clock_event_device *unused)
+					  struct clock_event_device *clk)
 {
-	set_next_event(ARCH_TIMER_VIRT_ACCESS, evt);
+	set_next_event(ARCH_TIMER_VIRT_ACCESS, evt, clk);
 	return 0;
 }
 
 static int arch_timer_set_next_event_phys(unsigned long evt,
-					  struct clock_event_device *unused)
+					  struct clock_event_device *clk)
 {
-	set_next_event(ARCH_TIMER_PHYS_ACCESS, evt);
+	set_next_event(ARCH_TIMER_PHYS_ACCESS, evt, clk);
 	return 0;
 }
 

From 220069945b298d3998c6598b081c466dca259929 Mon Sep 17 00:00:00 2001
From: Stephen Boyd <sboyd@codeaurora.org>
Date: Thu, 18 Jul 2013 16:59:32 -0700
Subject: [PATCH 23/23] clocksource: arch_timer: Add support for memory mapped
 timers

Add support for the memory mapped timers by filling in the
read/write functions and adding some parsing code. Note that we
only register one clocksource, preferring the cp15 based
clocksource over the mmio one.

To keep things simple we register one global clockevent. This
covers the case of UP and SMP systems with only mmio hardware and
systems where the memory mapped timers are used as the broadcast
timer in low power modes.

The DT binding allows for per-CPU memory mapped timers in case we
want to support that in the future, but the code isn't added
here. We also don't do much for hypervisor support, although it
should be possible to support it by searching for at least two
frames where one frame has the virtual capability and then
updating KVM timers to support it.

Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Marc Zyngier <Marc.Zyngier@arm.com>
Cc: Rob Herring <robherring2@gmail.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
---
 drivers/clocksource/arm_arch_timer.c | 404 +++++++++++++++++++++++----
 include/clocksource/arm_arch_timer.h |   4 +-
 2 files changed, 351 insertions(+), 57 deletions(-)

diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index a9ca28447b49..b3df46d9918b 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -16,13 +16,39 @@
 #include <linux/clockchips.h>
 #include <linux/interrupt.h>
 #include <linux/of_irq.h>
+#include <linux/of_address.h>
 #include <linux/io.h>
+#include <linux/slab.h>
 
 #include <asm/arch_timer.h>
 #include <asm/virt.h>
 
 #include <clocksource/arm_arch_timer.h>
 
+#define CNTTIDR		0x08
+#define CNTTIDR_VIRT(n)	(BIT(1) << ((n) * 4))
+
+#define CNTVCT_LO	0x08
+#define CNTVCT_HI	0x0c
+#define CNTFRQ		0x10
+#define CNTP_TVAL	0x28
+#define CNTP_CTL	0x2c
+#define CNTV_TVAL	0x38
+#define CNTV_CTL	0x3c
+
+#define ARCH_CP15_TIMER	BIT(0)
+#define ARCH_MEM_TIMER	BIT(1)
+static unsigned arch_timers_present __initdata;
+
+static void __iomem *arch_counter_base;
+
+struct arch_timer {
+	void __iomem *base;
+	struct clock_event_device evt;
+};
+
+#define to_arch_timer(e) container_of(e, struct arch_timer, evt)
+
 static u32 arch_timer_rate;
 
 enum ppi_nr {
@@ -38,6 +64,7 @@ static int arch_timer_ppi[MAX_TIMER_PPI];
 static struct clock_event_device __percpu *arch_timer_evt;
 
 static bool arch_timer_use_virtual = true;
+static bool arch_timer_mem_use_virtual;
 
 /*
  * Architected system timer support.
@@ -47,14 +74,62 @@ static __always_inline
 void arch_timer_reg_write(int access, enum arch_timer_reg reg, u32 val,
 		struct clock_event_device *clk)
 {
-	arch_timer_reg_write_cp15(access, reg, val);
+	if (access == ARCH_TIMER_MEM_PHYS_ACCESS) {
+		struct arch_timer *timer = to_arch_timer(clk);
+		switch (reg) {
+		case ARCH_TIMER_REG_CTRL:
+			writel_relaxed(val, timer->base + CNTP_CTL);
+			break;
+		case ARCH_TIMER_REG_TVAL:
+			writel_relaxed(val, timer->base + CNTP_TVAL);
+			break;
+		}
+	} else if (access == ARCH_TIMER_MEM_VIRT_ACCESS) {
+		struct arch_timer *timer = to_arch_timer(clk);
+		switch (reg) {
+		case ARCH_TIMER_REG_CTRL:
+			writel_relaxed(val, timer->base + CNTV_CTL);
+			break;
+		case ARCH_TIMER_REG_TVAL:
+			writel_relaxed(val, timer->base + CNTV_TVAL);
+			break;
+		}
+	} else {
+		arch_timer_reg_write_cp15(access, reg, val);
+	}
 }
 
 static __always_inline
 u32 arch_timer_reg_read(int access, enum arch_timer_reg reg,
 		struct clock_event_device *clk)
 {
-	return arch_timer_reg_read_cp15(access, reg);
+	u32 val;
+
+	if (access == ARCH_TIMER_MEM_PHYS_ACCESS) {
+		struct arch_timer *timer = to_arch_timer(clk);
+		switch (reg) {
+		case ARCH_TIMER_REG_CTRL:
+			val = readl_relaxed(timer->base + CNTP_CTL);
+			break;
+		case ARCH_TIMER_REG_TVAL:
+			val = readl_relaxed(timer->base + CNTP_TVAL);
+			break;
+		}
+	} else if (access == ARCH_TIMER_MEM_VIRT_ACCESS) {
+		struct arch_timer *timer = to_arch_timer(clk);
+		switch (reg) {
+		case ARCH_TIMER_REG_CTRL:
+			val = readl_relaxed(timer->base + CNTV_CTL);
+			break;
+		case ARCH_TIMER_REG_TVAL:
+			val = readl_relaxed(timer->base + CNTV_TVAL);
+			break;
+		}
+	} else {
+		val = arch_timer_reg_read_cp15(access, reg);
+	}
+
+	return val;
 }
 
 static __always_inline irqreturn_t timer_handler(const int access,
@@ -86,6 +161,20 @@ static irqreturn_t arch_timer_handler_phys(int irq, void *dev_id)
 	return timer_handler(ARCH_TIMER_PHYS_ACCESS, evt);
 }
 
+static irqreturn_t arch_timer_handler_phys_mem(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = dev_id;
+
+	return timer_handler(ARCH_TIMER_MEM_PHYS_ACCESS, evt);
+}
+
+static irqreturn_t arch_timer_handler_virt_mem(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = dev_id;
+
+	return timer_handler(ARCH_TIMER_MEM_VIRT_ACCESS, evt);
+}
+
 static __always_inline void timer_set_mode(const int access, int mode,
 				  struct clock_event_device *clk)
 {
@@ -114,6 +203,18 @@ static void arch_timer_set_mode_phys(enum clock_event_mode mode,
 	timer_set_mode(ARCH_TIMER_PHYS_ACCESS, mode, clk);
 }
 
+static void arch_timer_set_mode_virt_mem(enum clock_event_mode mode,
+					 struct clock_event_device *clk)
+{
+	timer_set_mode(ARCH_TIMER_MEM_VIRT_ACCESS, mode, clk);
+}
+
+static void arch_timer_set_mode_phys_mem(enum clock_event_mode mode,
+					 struct clock_event_device *clk)
+{
+	timer_set_mode(ARCH_TIMER_MEM_PHYS_ACCESS, mode, clk);
+}
+
 static __always_inline void set_next_event(const int access, unsigned long evt,
 				  struct clock_event_device *clk)
 {
@@ -139,27 +240,62 @@ static int arch_timer_set_next_event_phys(unsigned long evt,
 	return 0;
 }
 
-static int __cpuinit arch_timer_setup(struct clock_event_device *clk)
+static int arch_timer_set_next_event_virt_mem(unsigned long evt,
+					      struct clock_event_device *clk)
 {
-	clk->features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_C3STOP;
-	clk->name = "arch_sys_timer";
-	clk->rating = 450;
-	if (arch_timer_use_virtual) {
-		clk->irq = arch_timer_ppi[VIRT_PPI];
-		clk->set_mode = arch_timer_set_mode_virt;
-		clk->set_next_event = arch_timer_set_next_event_virt;
-	} else {
-		clk->irq = arch_timer_ppi[PHYS_SECURE_PPI];
-		clk->set_mode = arch_timer_set_mode_phys;
-		clk->set_next_event = arch_timer_set_next_event_phys;
-	}
+	set_next_event(ARCH_TIMER_MEM_VIRT_ACCESS, evt, clk);
+	return 0;
+}
 
-	clk->cpumask = cpumask_of(smp_processor_id());
+static int arch_timer_set_next_event_phys_mem(unsigned long evt,
+					      struct clock_event_device *clk)
+{
+	set_next_event(ARCH_TIMER_MEM_PHYS_ACCESS, evt, clk);
+	return 0;
+}
+
+static void __cpuinit __arch_timer_setup(unsigned type,
+				       struct clock_event_device *clk)
+{
+	clk->features = CLOCK_EVT_FEAT_ONESHOT;
+
+	if (type == ARCH_CP15_TIMER) {
+		clk->features |= CLOCK_EVT_FEAT_C3STOP;
+		clk->name = "arch_sys_timer";
+		clk->rating = 450;
+		clk->cpumask = cpumask_of(smp_processor_id());
+		if (arch_timer_use_virtual) {
+			clk->irq = arch_timer_ppi[VIRT_PPI];
+			clk->set_mode = arch_timer_set_mode_virt;
+			clk->set_next_event = arch_timer_set_next_event_virt;
+		} else {
+			clk->irq = arch_timer_ppi[PHYS_SECURE_PPI];
+			clk->set_mode = arch_timer_set_mode_phys;
+			clk->set_next_event = arch_timer_set_next_event_phys;
+		}
+	} else {
+		clk->name = "arch_mem_timer";
+		clk->rating = 400;
+		clk->cpumask = cpu_all_mask;
+		if (arch_timer_mem_use_virtual) {
+			clk->set_mode = arch_timer_set_mode_virt_mem;
+			clk->set_next_event =
+				arch_timer_set_next_event_virt_mem;
+		} else {
+			clk->set_mode = arch_timer_set_mode_phys_mem;
+			clk->set_next_event =
+				arch_timer_set_next_event_phys_mem;
+		}
+	}
 
 	clk->set_mode(CLOCK_EVT_MODE_SHUTDOWN, clk);
 
-	clockevents_config_and_register(clk, arch_timer_rate,
-					0xf, 0x7fffffff);
+	clockevents_config_and_register(clk, arch_timer_rate, 0xf, 0x7fffffff);
+}
+
+static int __cpuinit arch_timer_setup(struct clock_event_device *clk)
+{
+	__arch_timer_setup(ARCH_CP15_TIMER, clk);
 
 	if (arch_timer_use_virtual)
 		enable_percpu_irq(arch_timer_ppi[VIRT_PPI], 0);
@@ -174,27 +310,41 @@ static int __cpuinit arch_timer_setup(struct clock_event_device *clk)
 	return 0;
 }
 
-static int arch_timer_available(void)
+static void
+arch_timer_detect_rate(void __iomem *cntbase, struct device_node *np)
 {
-	u32 freq;
+	/* Who has more than one independent system counter? */
+	if (arch_timer_rate)
+		return;
 
-	if (arch_timer_rate == 0) {
-		freq = arch_timer_get_cntfrq();
-
-		/* Check the timer frequency. */
-		if (freq == 0) {
-			pr_warn("Architected timer frequency not available\n");
-			return -EINVAL;
-		}
-
-		arch_timer_rate = freq;
+	/* Try to determine the frequency from the device tree or CNTFRQ */
+	if (of_property_read_u32(np, "clock-frequency", &arch_timer_rate)) {
+		if (cntbase)
+			arch_timer_rate = readl_relaxed(cntbase + CNTFRQ);
+		else
+			arch_timer_rate = arch_timer_get_cntfrq();
 	}
 
-	pr_info_once("Architected local timer running at %lu.%02luMHz (%s).\n",
+	/* Check the timer frequency. */
+	if (arch_timer_rate == 0)
+		pr_warn("Architected timer frequency not available\n");
+}
+
+static void arch_timer_banner(unsigned type)
+{
+	pr_info("Architected %s%s%s timer(s) running at %lu.%02luMHz (%s%s%s).\n",
+		     type & ARCH_CP15_TIMER ? "cp15" : "",
+		     type == (ARCH_CP15_TIMER | ARCH_MEM_TIMER) ?  " and " : "",
+		     type & ARCH_MEM_TIMER ? "mmio" : "",
 		     (unsigned long)arch_timer_rate / 1000000,
 		     (unsigned long)(arch_timer_rate / 10000) % 100,
-		     arch_timer_use_virtual ? "virt" : "phys");
-	return 0;
+		     type & ARCH_CP15_TIMER ?
+			arch_timer_use_virtual ? "virt" : "phys" :
+			"",
+		     type == (ARCH_CP15_TIMER | ARCH_MEM_TIMER) ?  "/" : "",
+		     type & ARCH_MEM_TIMER ?
+			arch_timer_mem_use_virtual ? "virt" : "phys" :
+			"");
 }
 
 u32 arch_timer_get_rate(void)
@@ -202,19 +352,35 @@ u32 arch_timer_get_rate(void)
 	return arch_timer_rate;
 }
 
-u64 arch_timer_read_counter(void)
+static u64 arch_counter_get_cntvct_mem(void)
 {
-	return arch_counter_get_cntvct();
+	u32 vct_lo, vct_hi, tmp_hi;
+
+	do {
+		vct_hi = readl_relaxed(arch_counter_base + CNTVCT_HI);
+		vct_lo = readl_relaxed(arch_counter_base + CNTVCT_LO);
+		tmp_hi = readl_relaxed(arch_counter_base + CNTVCT_HI);
+	} while (vct_hi != tmp_hi);
+
+	return ((u64) vct_hi << 32) | vct_lo;
 }
 
+/*
+ * Default to cp15 based access because arm64 uses this function for
+ * sched_clock() before DT is probed and the cp15 method is guaranteed
+ * to exist on arm64. arm doesn't use this before DT is probed so even
+ * if we don't have the cp15 accessors we won't have a problem.
+ */
+u64 (*arch_timer_read_counter)(void) = arch_counter_get_cntvct;
+
 static cycle_t arch_counter_read(struct clocksource *cs)
 {
-	return arch_counter_get_cntvct();
+	return arch_timer_read_counter();
 }
 
 static cycle_t arch_counter_read_cc(const struct cyclecounter *cc)
 {
-	return arch_counter_get_cntvct();
+	return arch_timer_read_counter();
 }
 
 static struct clocksource clocksource_counter = {
@@ -237,6 +403,23 @@ struct timecounter *arch_timer_get_timecounter(void)
 	return &timecounter;
 }
 
+static void __init arch_counter_register(unsigned type)
+{
+	u64 start_count;
+
+	/* Register the CP15 based counter if we have one */
+	if (type & ARCH_CP15_TIMER)
+		arch_timer_read_counter = arch_counter_get_cntvct;
+	else
+		arch_timer_read_counter = arch_counter_get_cntvct_mem;
+
+	start_count = arch_timer_read_counter();
+	clocksource_register_hz(&clocksource_counter, arch_timer_rate);
+	cyclecounter.mult = clocksource_counter.mult;
+	cyclecounter.shift = clocksource_counter.shift;
+	timecounter_init(&timecounter, &cyclecounter, start_count);
+}
+
 static void __cpuinit arch_timer_stop(struct clock_event_device *clk)
 {
 	pr_debug("arch_timer_teardown disable IRQ%d cpu #%d\n",
@@ -281,22 +464,12 @@ static int __init arch_timer_register(void)
 	int err;
 	int ppi;
 
-	err = arch_timer_available();
-	if (err)
-		goto out;
-
 	arch_timer_evt = alloc_percpu(struct clock_event_device);
 	if (!arch_timer_evt) {
 		err = -ENOMEM;
 		goto out;
 	}
 
-	clocksource_register_hz(&clocksource_counter, arch_timer_rate);
-	cyclecounter.mult = clocksource_counter.mult;
-	cyclecounter.shift = clocksource_counter.shift;
-	timecounter_init(&timecounter, &cyclecounter,
-			 arch_counter_get_cntvct());
-
 	if (arch_timer_use_virtual) {
 		ppi = arch_timer_ppi[VIRT_PPI];
 		err = request_percpu_irq(ppi, arch_timer_handler_virt,
@@ -347,24 +520,77 @@ out:
 	return err;
 }
 
+static int __init arch_timer_mem_register(void __iomem *base, unsigned int irq)
+{
+	int ret;
+	irq_handler_t func;
+	struct arch_timer *t;
+
+	t = kzalloc(sizeof(*t), GFP_KERNEL);
+	if (!t)
+		return -ENOMEM;
+
+	t->base = base;
+	t->evt.irq = irq;
+	__arch_timer_setup(ARCH_MEM_TIMER, &t->evt);
+
+	if (arch_timer_mem_use_virtual)
+		func = arch_timer_handler_virt_mem;
+	else
+		func = arch_timer_handler_phys_mem;
+
+	ret = request_irq(irq, func, IRQF_TIMER, "arch_mem_timer", &t->evt);
+	if (ret) {
+		pr_err("arch_timer: Failed to request mem timer irq\n");
+		kfree(t);
+	}
+
+	return ret;
+}
+
+static const struct of_device_id arch_timer_of_match[] __initconst = {
+	{ .compatible   = "arm,armv7-timer",    },
+	{ .compatible   = "arm,armv8-timer",    },
+	{},
+};
+
+static const struct of_device_id arch_timer_mem_of_match[] __initconst = {
+	{ .compatible   = "arm,armv7-timer-mem", },
+	{},
+};
+
+static void __init arch_timer_common_init(void)
+{
+	unsigned mask = ARCH_CP15_TIMER | ARCH_MEM_TIMER;
+
+	/* Wait until both nodes are probed if we have two timers */
+	if ((arch_timers_present & mask) != mask) {
+		if (of_find_matching_node(NULL, arch_timer_mem_of_match) &&
+				!(arch_timers_present & ARCH_MEM_TIMER))
+			return;
+		if (of_find_matching_node(NULL, arch_timer_of_match) &&
+				!(arch_timers_present & ARCH_CP15_TIMER))
+			return;
+	}
+
+	arch_timer_banner(arch_timers_present);
+	arch_counter_register(arch_timers_present);
+	arch_timer_arch_init();
+}
+
 static void __init arch_timer_init(struct device_node *np)
 {
-	u32 freq;
 	int i;
 
-	if (arch_timer_get_rate()) {
+	if (arch_timers_present & ARCH_CP15_TIMER) {
 		pr_warn("arch_timer: multiple nodes in dt, skipping\n");
 		return;
 	}
 
-	/* Try to determine the frequency from the device tree or CNTFRQ */
-	if (!of_property_read_u32(np, "clock-frequency", &freq))
-		arch_timer_rate = freq;
-
+	arch_timers_present |= ARCH_CP15_TIMER;
 	for (i = PHYS_SECURE_PPI; i < MAX_TIMER_PPI; i++)
 		arch_timer_ppi[i] = irq_of_parse_and_map(np, i);
-
-	of_node_put(np);
+	arch_timer_detect_rate(NULL, np);
 
 	/*
 	 * If HYP mode is available, we know that the physical timer
@@ -385,7 +611,73 @@ static void __init arch_timer_init(struct device_node *np)
 	}
 
 	arch_timer_register();
-	arch_timer_arch_init();
+	arch_timer_common_init();
 }
 CLOCKSOURCE_OF_DECLARE(armv7_arch_timer, "arm,armv7-timer", arch_timer_init);
 CLOCKSOURCE_OF_DECLARE(armv8_arch_timer, "arm,armv8-timer", arch_timer_init);
+
+static void __init arch_timer_mem_init(struct device_node *np)
+{
+	struct device_node *frame, *best_frame = NULL;
+	void __iomem *cntctlbase, *base;
+	unsigned int irq;
+	u32 cnttidr;
+
+	arch_timers_present |= ARCH_MEM_TIMER;
+	cntctlbase = of_iomap(np, 0);
+	if (!cntctlbase) {
+		pr_err("arch_timer: Can't find CNTCTLBase\n");
+		return;
+	}
+
+	cnttidr = readl_relaxed(cntctlbase + CNTTIDR);
+	iounmap(cntctlbase);
+
+	/*
+	 * Try to find a virtual capable frame. Otherwise fall back to a
+	 * physical capable frame.
+	 */
+	for_each_available_child_of_node(np, frame) {
+		int n;
+
+		if (of_property_read_u32(frame, "frame-number", &n)) {
+			pr_err("arch_timer: Missing frame-number\n");
+			of_node_put(best_frame);
+			of_node_put(frame);
+			return;
+		}
+
+		if (cnttidr & CNTTIDR_VIRT(n)) {
+			of_node_put(best_frame);
+			best_frame = frame;
+			arch_timer_mem_use_virtual = true;
+			break;
+		}
+		of_node_put(best_frame);
+		best_frame = of_node_get(frame);
+	}
+
+	base = arch_counter_base = of_iomap(best_frame, 0);
+	if (!base) {
+		pr_err("arch_timer: Can't map frame's registers\n");
+		of_node_put(best_frame);
+		return;
+	}
+
+	if (arch_timer_mem_use_virtual)
+		irq = irq_of_parse_and_map(best_frame, 1);
+	else
+		irq = irq_of_parse_and_map(best_frame, 0);
+	of_node_put(best_frame);
+	if (!irq) {
+		pr_err("arch_timer: Frame missing %s irq",
+				arch_timer_mem_use_virtual ? "virt" : "phys");
+		return;
+	}
+
+	arch_timer_detect_rate(base, np);
+	arch_timer_mem_register(base, irq);
+	arch_timer_common_init();
+}
+CLOCKSOURCE_OF_DECLARE(armv7_arch_timer_mem, "arm,armv7-timer-mem",
+		       arch_timer_mem_init);
diff --git a/include/clocksource/arm_arch_timer.h b/include/clocksource/arm_arch_timer.h
index f3da817b9b8e..93b7f96f9c59 100644
--- a/include/clocksource/arm_arch_timer.h
+++ b/include/clocksource/arm_arch_timer.h
@@ -30,11 +30,13 @@ enum arch_timer_reg {
 
 #define ARCH_TIMER_PHYS_ACCESS		0
 #define ARCH_TIMER_VIRT_ACCESS		1
+#define ARCH_TIMER_MEM_PHYS_ACCESS	2
+#define ARCH_TIMER_MEM_VIRT_ACCESS	3
 
 #ifdef CONFIG_ARM_ARCH_TIMER
 
 extern u32 arch_timer_get_rate(void);
-extern u64 arch_timer_read_counter(void);
+extern u64 (*arch_timer_read_counter)(void);
 extern struct timecounter *arch_timer_get_timecounter(void);
 
 #else