[PATCH-V7 0/3] ARM: OMAP: Make OMAP clocksource source selection runtime

[PATCH-V7 0/3] ARM: OMAP: Make OMAP clocksource source selection runtime

[Vaibhav Hiremath]

Current OMAP code supports couple of clocksource options based
on compilation flag (CONFIG_OMAP_32K_TIMER). The 32KHz sync-timer
and a gptimer which can run on 32KHz or system clock (e.g 38.4 MHz)

This patch series cleans up the existing 32k-sync timer implementation,
movind SoC init code to respective files (mach-omap1/timer32k.c and
mach-omap2/timer.c) and uses kernel parameter to override the default
clocksource of "counter_32k", also in order to support some OMAP based
derivative SoCs like AM33XX which doesn't have 32K sync-timer hardware IP,
adds hwmod lookup for omap2+ devices, and if lookup fails then
fall back to gp-timer.

if(use_gptimer_clksrc == true)
	gptimer clocksource init;
else if (counter_32 init == false)
	/* Fallback to gptimer */
	gptimer clocksource init(;

With this, we should be able to support multi-omap boot
including devices with/without 32k-sync timer.

This patch-series has been boot tested on AM37xEVM platform, it
would be helpful if somebody help me to validate it on OMAP1/2
platforms.

The patches are also available at (based on linux-omap/master) -
https://github.com/hvaibhav/am335x-linux   32ksync-timer-cleanup

History:
========
Changes from V6:
http://www.mail-archive.com/linux-omap at vger.kernel.org/msg67623.html
	- Changed Patch2/3 descrption to add affected kernel parameter
	- Warning Fix: Added missing inline prefix to omap_32k_timer_init()
	- Added Acked-by and Tested-by from Kevin Hilman

Changes from V5:
http://www.mail-archive.com/linux-omap at vger.kernel.org/msg67163.html
	- 2 of the original patch-series (1/3 and 2/3) has already been
	  accepted and queued by Paul, so removing them.
	  Also, add 2 new patches,
		- OMAP2 timer32k cleanup, check for return values.
		- Changed name of system timers, "gp timer" => "gp_timer".
	- Moved SoC specific init code to respective files
	  (mach-omap1/timer32k.c and mach-omap2/timer.c)

Changes from V4:
http://www.mail-archive.com/linux-omap at vger.kernel.org/msg67019.html
	- Fix the possible bug, leftover the cnt addr argument to
	  clocksource_mmio_init().

Changes from V3:
http://www.mail-archive.com/linux-omap at vger.kernel.org/msg66462.html
	- Fixed all review comments from Kevin H
		* Moved counter_32k CR register offset handling to
		  counter_32k.c file, so now, calling funtion don't have
		  to maintain or add offset to base addr.
		* Added comment for function omap_init_clocksource_32k()
		* Used resource_size() for calculate size
		* Convert WARN_ON to pr_warn

Changes from V2:
http://lists.infradead.org/pipermail/linux-arm-kernel/2012-March/092037.html
	- Added early_param support to read clocksource selection
	  from user through kernel parameter ("clocksource=")
	- Converted to ocp_if changes from Paul

Changes from V1:
http://lists.infradead.org/pipermail/linux-arm-kernel/2012-January/081037.html
	- Based on Tony's comment, added pbase & size argument to
	  omap_init_clocksource_32k(), to avoid cpu_is_xxx() check.
	- Added commit description based on discussion on list
	  (Thanks to Santosh here)
	- Reorder patch sequence


Vaibhav Hiremath (3):
  ARM: OMAP1: FIX: check possible error condition in timer_init
  ARM: OMAP2+: Replace space=>underscore in the name field of system
    timers
  ARM: OMAP: Make OMAP clocksource source selection using kernel param

 arch/arm/mach-omap1/common.h             |   10 ++-
 arch/arm/mach-omap1/time.c               |   16 +----
 arch/arm/mach-omap1/timer32k.c           |   28 ++++++-
 arch/arm/mach-omap2/timer.c              |  118 +++++++++++++++++++++++------
 arch/arm/plat-omap/counter_32k.c         |   91 ++++++++++-------------
 arch/arm/plat-omap/include/plat/common.h |    2 +-
 6 files changed, 167 insertions(+), 98 deletions(-)

[PATCH-V7 1/3] ARM: OMAP1: FIX: check possible error condition in timer_init

[Vaibhav Hiremath]

On OMAP1, omap_32k_timer_init() function always returns "true",
irrespective of whether error occurred while initializing 32k sync
counter as a kernel clocksource or not and execution will never
fallback to mpu_timer clocksource init code.

This patch adds check for return value from function
omap_init_clocksource_32k(), and fallback to omap_mpu_timer_init()
in case of failure/error from omap_init_clocksource_32k().

Signed-off-by: Vaibhav Hiremath <hvaibhav@ti.com>
Acked-by: Kevin Hilman <khilman@ti.com>
Tested-by: Kevin Hilman <khilman@ti.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Benoit Cousson <b-cousson@ti.com>
---
No Functional code change compared to V6 version, only 'inline'
prefix added to the function omap_32k_timer_init(), required to
fix warning (Thanks to Kevin).

 arch/arm/mach-omap1/common.h   |   10 +++++++++-
 arch/arm/mach-omap1/time.c     |   16 +---------------
 arch/arm/mach-omap1/timer32k.c |   13 +++++++++----
 3 files changed, 19 insertions(+), 20 deletions(-)

diff --git a/arch/arm/mach-omap1/common.h b/arch/arm/mach-omap1/common.h
index 8cc616e..cc83251 100644
--- a/arch/arm/mach-omap1/common.h
+++ b/arch/arm/mach-omap1/common.h
@@ -63,7 +63,15 @@ extern void omap1_nand_cmd_ctl(struct mtd_info *mtd, int cmd,
 			       unsigned int ctrl);

 extern struct sys_timer omap1_timer;
-extern bool omap_32k_timer_init(void);
+
+#ifdef CONFIG_OMAP_32K_TIMER
+extern int omap_32k_timer_init(void);
+#else
+static inline int __init omap_32k_timer_init(void)
+{
+	return -ENODEV;
+}
+#endif

 extern u32 omap_irq_flags;

diff --git a/arch/arm/mach-omap1/time.c b/arch/arm/mach-omap1/time.c
index 4d8dd9a..4062480 100644
--- a/arch/arm/mach-omap1/time.c
+++ b/arch/arm/mach-omap1/time.c
@@ -232,20 +232,6 @@ static inline void omap_mpu_timer_init(void)
 }
 #endif	/* CONFIG_OMAP_MPU_TIMER */

-static inline int omap_32k_timer_usable(void)
-{
-	int res = false;
-
-	if (cpu_is_omap730() || cpu_is_omap15xx())
-		return res;
-
-#ifdef CONFIG_OMAP_32K_TIMER
-	res = omap_32k_timer_init();
-#endif
-
-	return res;
-}
-
 /*
  * ---------------------------------------------------------------------------
  * Timer initialization
@@ -253,7 +239,7 @@ static inline int omap_32k_timer_usable(void)
  */
 static void __init omap1_timer_init(void)
 {
-	if (!omap_32k_timer_usable())
+	if (omap_32k_timer_init() != 0)
 		omap_mpu_timer_init();
 }

diff --git a/arch/arm/mach-omap1/timer32k.c b/arch/arm/mach-omap1/timer32k.c
index 325b9a0..e3613a8 100644
--- a/arch/arm/mach-omap1/timer32k.c
+++ b/arch/arm/mach-omap1/timer32k.c
@@ -182,10 +182,15 @@ static __init void omap_init_32k_timer(void)
  * Timer initialization
  * ---------------------------------------------------------------------------
  */
-bool __init omap_32k_timer_init(void)
+int __init omap_32k_timer_init(void)
 {
-	omap_init_clocksource_32k();
-	omap_init_32k_timer();
+	int ret = -ENODEV;

-	return true;
+	if (cpu_is_omap16xx())
+		ret = omap_init_clocksource_32k();
+
+	if (!ret)
+		omap_init_32k_timer();
+
+	return ret;
 }
--
1.7.0.4

[PATCH-V7 2/3] ARM: OMAP2+: Replace space=>underscore in the name field of system timers

[Vaibhav Hiremath]

Depending on the bootloader, passing command-line arguments
with spaces may have issues. Some bootloaders doesn't seem
to pass along the quotes, passing only 'gp' part of the string,
which leads to wrong override configuration.

The only affected kernel parameter configuration for OMAP family
is "clocksource=", used to override kernel clocksource.

So this patch changes "gp timer" => "gp_timer", for clockevent,
clocksource and timer irq_handler.

Signed-off-by: Vaibhav Hiremath <hvaibhav@ti.com>
Acked-by: Kevin Hilman <khilman@ti.com>
Tested-by: Kevin Hilman <khilman@ti.com>
Cc: Santosh Shilimkar <santosh.shilimkar@ti.com>
Cc: Benoit Cousson <b-cousson@ti.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Paul Walmsley <paul@pwsan.com>
---
No code change compared to V6 patch series, only
commit description has been updated as per Kevin's comment.

 arch/arm/mach-omap2/timer.c |    6 +++---
 1 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/arm/mach-omap2/timer.c b/arch/arm/mach-omap2/timer.c
index ecec873..777f84b 100644
--- a/arch/arm/mach-omap2/timer.c
+++ b/arch/arm/mach-omap2/timer.c
@@ -90,7 +90,7 @@ static irqreturn_t omap2_gp_timer_interrupt(int irq, void *dev_id)
 }

 static struct irqaction omap2_gp_timer_irq = {
-	.name		= "gp timer",
+	.name		= "gp_timer",
 	.flags		= IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
 	.handler	= omap2_gp_timer_interrupt,
 };
@@ -132,7 +132,7 @@ static void omap2_gp_timer_set_mode(enum clock_event_mode mode,
 }

 static struct clock_event_device clockevent_gpt = {
-	.name		= "gp timer",
+	.name		= "gp_timer",
 	.features       = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
 	.shift		= 32,
 	.set_next_event	= omap2_gp_timer_set_next_event,
@@ -269,7 +269,7 @@ static cycle_t clocksource_read_cycles(struct clocksource *cs)
 }

 static struct clocksource clocksource_gpt = {
-	.name		= "gp timer",
+	.name		= "gp_timer",
 	.rating		= 300,
 	.read		= clocksource_read_cycles,
 	.mask		= CLOCKSOURCE_MASK(32),
--
1.7.0.4

[PATCH-V7 3/3] ARM: OMAP: Make OMAP clocksource source selection using kernel param

[Vaibhav Hiremath]

Current OMAP code supports couple of clocksource options based
on compilation flag (CONFIG_OMAP_32K_TIMER). The 32KHz sync-timer
and a gptimer which can run on 32KHz or system clock (e.g 38.4 MHz).
So there can be 3 options -

1. 32KHz sync-timer
2. Sys_clock based (e.g 13/19.2/26/38.4 MHz) gptimer
3. 32KHz based gptimer.

The optional gptimer based clocksource was added so that it can
give the high precision than sync-timer, so expected usage was 2
and not 3.
Unfortunately option 2, clocksource doesn't meet the requirement of
free-running clock as per clocksource need. It stops in low power states
when sys_clock is cut. That makes gptimer based clocksource option
useless for OMAP2/3/4 devices with sys_clock as a clock input.
So, in order to use option 2, deeper idle state MUST be disabled.

Option 3 will still work but it is no better than 32K sync-timer
based clocksource.

We must support both sync timer and gptimer based clocksource as
some OMAP based derivative SoCs like AM33XX does not have the
sync timer.

Considering above, make sync-timer and gptimer clocksource runtime
selectable so that both OMAP and AMXXXX continue to use the same code.

And, in order to precisely configure/setup sched_clock for given
clocksource, decision has to be made early enough in boot sequence.

So, the solution is,

Use standard kernel parameter ("clocksource=") to override
default 32k_sync-timer, in addition to this, we also use hwmod database
lookup mechanism, through which at run-time we can identify availability
of 32k-sync timer on the device, else fall back to gptimer.

Also, moved low-level SoC specific init code to respective files,
(mach-omap1/timer32k.c and mach-omap2/timer.c)

Signed-off-by: Vaibhav Hiremath <hvaibhav@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Kevin Hilman <khilman@ti.com>
Tested-by: Kevin Hilman <khilman@ti.com>
Cc: Benoit Cousson <b-cousson@ti.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Tarun Kanti DebBarma <tarun.kanti@ti.com>
Cc: Ming Lei <tom.leiming@gmail.com>
---
No code change compared to V6 patch series.

 arch/arm/mach-omap1/timer32k.c           |   19 +++++-
 arch/arm/mach-omap2/timer.c              |  112 ++++++++++++++++++++++++------
 arch/arm/plat-omap/counter_32k.c         |   91 ++++++++++--------------
 arch/arm/plat-omap/include/plat/common.h |    2 +-
 4 files changed, 147 insertions(+), 77 deletions(-)

diff --git a/arch/arm/mach-omap1/timer32k.c b/arch/arm/mach-omap1/timer32k.c
index e3613a8..eae49c3 100644
--- a/arch/arm/mach-omap1/timer32k.c
+++ b/arch/arm/mach-omap1/timer32k.c
@@ -71,6 +71,7 @@

 /* 16xx specific defines */
 #define OMAP1_32K_TIMER_BASE		0xfffb9000
+#define OMAP1_32KSYNC_TIMER_BASE	0xfffbc400
 #define OMAP1_32K_TIMER_CR		0x08
 #define OMAP1_32K_TIMER_TVR		0x00
 #define OMAP1_32K_TIMER_TCR		0x04
@@ -186,8 +187,22 @@ int __init omap_32k_timer_init(void)
 {
 	int ret = -ENODEV;

-	if (cpu_is_omap16xx())
-		ret = omap_init_clocksource_32k();
+	if (cpu_is_omap16xx()) {
+		void __iomem *base;
+		struct clk *sync32k_ick;
+
+		base = ioremap(OMAP1_32KSYNC_TIMER_BASE, SZ_1K);
+		if (!base) {
+			pr_err("32k_counter: failed to map base addr\n");
+			return -ENODEV;
+		}
+
+		sync32k_ick = clk_get(NULL, "omap_32ksync_ick");
+		if (!IS_ERR(sync32k_ick))
+			clk_enable(sync32k_ick);
+
+		ret = omap_init_clocksource_32k(base);
+	}

 	if (!ret)
 		omap_init_32k_timer();
diff --git a/arch/arm/mach-omap2/timer.c b/arch/arm/mach-omap2/timer.c
index 777f84b..30824b5 100644
--- a/arch/arm/mach-omap2/timer.c
+++ b/arch/arm/mach-omap2/timer.c
@@ -243,22 +243,8 @@ static void __init omap2_gp_clockevent_init(int gptimer_id,
 }

 /* Clocksource code */
-
-#ifdef CONFIG_OMAP_32K_TIMER
-/*
- * When 32k-timer is enabled, don't use GPTimer for clocksource
- * instead, just leave default clocksource which uses the 32k
- * sync counter.  See clocksource setup in plat-omap/counter_32k.c
- */
-
-static void __init omap2_gp_clocksource_init(int unused, const char *dummy)
-{
-	omap_init_clocksource_32k();
-}
-
-#else
-
 static struct omap_dm_timer clksrc;
+static bool use_gptimer_clksrc;

 /*
  * clocksource
@@ -285,7 +271,46 @@ static u32 notrace dmtimer_read_sched_clock(void)
 }

 /* Setup free-running counter for clocksource */
-static void __init omap2_gp_clocksource_init(int gptimer_id,
+static int __init omap2_sync32k_clocksource_init(void)
+{
+	int ret;
+	struct omap_hwmod *oh;
+	void __iomem *vbase;
+	const char *oh_name = "counter_32k";
+
+	/*
+	 * First check hwmod data is available for sync32k counter
+	 */
+	oh = omap_hwmod_lookup(oh_name);
+	if (!oh || oh->slaves_cnt == 0)
+		return -ENODEV;
+
+	omap_hwmod_setup_one(oh_name);
+
+	vbase = omap_hwmod_get_mpu_rt_va(oh);
+	if (!vbase) {
+		pr_warn("%s: failed to get counter_32k resource\n", __func__);
+		return -ENXIO;
+	}
+
+	ret = omap_hwmod_enable(oh);
+	if (ret) {
+		pr_warn("%s: failed to enable counter_32k module (%d)\n",
+							__func__, ret);
+		return ret;
+	}
+
+	ret = omap_init_clocksource_32k(vbase);
+	if (ret) {
+		pr_warn("%s: failed to initialize counter_32k as a clocksource (%d)\n",
+							__func__, ret);
+		omap_hwmod_idle(oh);
+	}
+
+	return ret;
+}
+
+static void __init omap2_gptimer_clocksource_init(int gptimer_id,
 						const char *fck_source)
 {
 	int res;
@@ -293,9 +318,6 @@ static void __init omap2_gp_clocksource_init(int gptimer_id,
 	res = omap_dm_timer_init_one(&clksrc, gptimer_id, fck_source);
 	BUG_ON(res);

-	pr_info("OMAP clocksource: GPTIMER%d at %lu Hz\n",
-		gptimer_id, clksrc.rate);
-
 	__omap_dm_timer_load_start(&clksrc,
 			OMAP_TIMER_CTRL_ST | OMAP_TIMER_CTRL_AR, 0, 1);
 	setup_sched_clock(dmtimer_read_sched_clock, 32, clksrc.rate);
@@ -303,15 +325,36 @@ static void __init omap2_gp_clocksource_init(int gptimer_id,
 	if (clocksource_register_hz(&clocksource_gpt, clksrc.rate))
 		pr_err("Could not register clocksource %s\n",
 			clocksource_gpt.name);
+	else
+		pr_info("OMAP clocksource: GPTIMER%d at %lu Hz\n",
+			gptimer_id, clksrc.rate);
+}
+
+static void __init omap2_clocksource_init(int gptimer_id,
+						const char *fck_source)
+{
+	/*
+	 * First give preference to kernel parameter configuration
+	 * by user (clocksource="gp_timer").
+	 *
+	 * In case of missing kernel parameter for clocksource,
+	 * first check for availability for 32k-sync timer, in case
+	 * of failure in finding 32k_counter module or registering
+	 * it as clocksource, execution will fallback to gp-timer.
+	 */
+	if (use_gptimer_clksrc == true)
+		omap2_gptimer_clocksource_init(gptimer_id, fck_source);
+	else if (omap2_sync32k_clocksource_init())
+		/* Fall back to gp-timer code */
+		omap2_gptimer_clocksource_init(gptimer_id, fck_source);
 }
-#endif

 #define OMAP_SYS_TIMER_INIT(name, clkev_nr, clkev_src,			\
 				clksrc_nr, clksrc_src)			\
 static void __init omap##name##_timer_init(void)			\
 {									\
 	omap2_gp_clockevent_init((clkev_nr), clkev_src);		\
-	omap2_gp_clocksource_init((clksrc_nr), clksrc_src);		\
+	omap2_clocksource_init((clksrc_nr), clksrc_src);		\
 }

 #define OMAP_SYS_TIMER(name)						\
@@ -342,7 +385,7 @@ static DEFINE_TWD_LOCAL_TIMER(twd_local_timer,
 static void __init omap4_timer_init(void)
 {
 	omap2_gp_clockevent_init(1, OMAP4_CLKEV_SOURCE);
-	omap2_gp_clocksource_init(2, OMAP4_MPU_SOURCE);
+	omap2_clocksource_init(2, OMAP4_MPU_SOURCE);
 #ifdef CONFIG_LOCAL_TIMERS
 	/* Local timers are not supprted on OMAP4430 ES1.0 */
 	if (omap_rev() != OMAP4430_REV_ES1_0) {
@@ -510,3 +553,28 @@ static int __init omap2_dm_timer_init(void)
 	return 0;
 }
 arch_initcall(omap2_dm_timer_init);
+
+/**
+ * omap2_override_clocksource - clocksource override with user configuration
+ *
+ * Allows user to override default clocksource, using kernel parameter
+ *   clocksource="gp_timer"	(For all OMAP2PLUS architectures)
+ *
+ * Note that, here we are using same standard kernel parameter "clocksource=",
+ * and not introducing any OMAP specific interface.
+ */
+static int __init omap2_override_clocksource(char *str)
+{
+	if (!str)
+		return 0;
+	/*
+	 * For OMAP architecture, we only have two options
+	 *    - sync_32k (default)
+	 *    - gp_timer (sys_clk based)
+	 */
+	if (!strcmp(str, "gp_timer"))
+		use_gptimer_clksrc = true;
+
+	return 0;
+}
+early_param("clocksource", omap2_override_clocksource);
diff --git a/arch/arm/plat-omap/counter_32k.c b/arch/arm/plat-omap/counter_32k.c
index 5068fe5..b2f634b 100644
--- a/arch/arm/plat-omap/counter_32k.c
+++ b/arch/arm/plat-omap/counter_32k.c
@@ -27,19 +27,20 @@

 #include <plat/clock.h>

+/* OMAP2_32KSYNCNT_CR_OFF: offset of 32ksync counter register */
+#define OMAP2_32KSYNCNT_CR_OFF		0x10
+
 /*
  * 32KHz clocksource ... always available, on pretty most chips except
  * OMAP 730 and 1510.  Other timers could be used as clocksources, with
  * higher resolution in free-running counter modes (e.g. 12 MHz xtal),
  * but systems won't necessarily want to spend resources that way.
  */
-static void __iomem *timer_32k_base;
-
-#define OMAP16XX_TIMER_32K_SYNCHRONIZED		0xfffbc410
+static void __iomem *sync32k_cnt_reg;

 static u32 notrace omap_32k_read_sched_clock(void)
 {
-	return timer_32k_base ? __raw_readl(timer_32k_base) : 0;
+	return sync32k_cnt_reg ? __raw_readl(sync32k_cnt_reg) : 0;
 }

 /**
@@ -59,7 +60,7 @@ void read_persistent_clock(struct timespec *ts)
 	struct timespec *tsp = &persistent_ts;

 	last_cycles = cycles;
-	cycles = timer_32k_base ? __raw_readl(timer_32k_base) : 0;
+	cycles = sync32k_cnt_reg ? __raw_readl(sync32k_cnt_reg) : 0;
 	delta = cycles - last_cycles;

 	nsecs = clocksource_cyc2ns(delta, persistent_mult, persistent_shift);
@@ -68,54 +69,40 @@ void read_persistent_clock(struct timespec *ts)
 	*ts = *tsp;
 }

-int __init omap_init_clocksource_32k(void)
+/**
+ * omap_init_clocksource_32k - setup and register counter 32k as a
+ * kernel clocksource
+ * @pbase: base addr of counter_32k module
+ * @size: size of counter_32k to map
+ *
+ * Returns 0 upon success or negative error code upon failure.
+ *
+ */
+int __init omap_init_clocksource_32k(void __iomem *vbase)
 {
-	static char err[] __initdata = KERN_ERR
-			"%s: can't register clocksource!\n";
-
-	if (cpu_is_omap16xx() || cpu_class_is_omap2()) {
-		u32 pbase;
-		unsigned long size = SZ_4K;
-		void __iomem *base;
-		struct clk *sync_32k_ick;
-
-		if (cpu_is_omap16xx()) {
-			pbase = OMAP16XX_TIMER_32K_SYNCHRONIZED;
-			size = SZ_1K;
-		} else if (cpu_is_omap2420())
-			pbase = OMAP2420_32KSYNCT_BASE + 0x10;
-		else if (cpu_is_omap2430())
-			pbase = OMAP2430_32KSYNCT_BASE + 0x10;
-		else if (cpu_is_omap34xx())
-			pbase = OMAP3430_32KSYNCT_BASE + 0x10;
-		else if (cpu_is_omap44xx())
-			pbase = OMAP4430_32KSYNCT_BASE + 0x10;
-		else
-			return -ENODEV;
-
-		/* For this to work we must have a static mapping in io.c for this area */
-		base = ioremap(pbase, size);
-		if (!base)
-			return -ENODEV;
-
-		sync_32k_ick = clk_get(NULL, "omap_32ksync_ick");
-		if (!IS_ERR(sync_32k_ick))
-			clk_enable(sync_32k_ick);
-
-		timer_32k_base = base;
-
-		/*
-		 * 120000 rough estimate from the calculations in
-		 * __clocksource_updatefreq_scale.
-		 */
-		clocks_calc_mult_shift(&persistent_mult, &persistent_shift,
-				32768, NSEC_PER_SEC, 120000);
-
-		if (clocksource_mmio_init(base, "32k_counter", 32768, 250, 32,
-					  clocksource_mmio_readl_up))
-			printk(err, "32k_counter");
-
-		setup_sched_clock(omap_32k_read_sched_clock, 32, 32768);
+	int ret;
+
+	/*
+	 * 32k sync Counter register offset is at 0x10
+	 */
+	sync32k_cnt_reg = vbase + OMAP2_32KSYNCNT_CR_OFF;
+
+	/*
+	 * 120000 rough estimate from the calculations in
+	 * __clocksource_updatefreq_scale.
+	 */
+	clocks_calc_mult_shift(&persistent_mult, &persistent_shift,
+			32768, NSEC_PER_SEC, 120000);
+
+	ret = clocksource_mmio_init(sync32k_cnt_reg, "32k_counter", 32768,
+				250, 32, clocksource_mmio_readl_up);
+	if (ret) {
+		pr_err("32k_counter: can't register clocksource\n");
+		return ret;
 	}
+
+	setup_sched_clock(omap_32k_read_sched_clock, 32, 32768);
+	pr_info("OMAP clocksource: 32k_counter at 32768 Hz\n");
+
 	return 0;
 }
diff --git a/arch/arm/plat-omap/include/plat/common.h b/arch/arm/plat-omap/include/plat/common.h
index a557b84..d1cb6f5 100644
--- a/arch/arm/plat-omap/include/plat/common.h
+++ b/arch/arm/plat-omap/include/plat/common.h
@@ -30,7 +30,7 @@
 #include <plat/i2c.h>
 #include <plat/omap_hwmod.h>

-extern int __init omap_init_clocksource_32k(void);
+extern int __init omap_init_clocksource_32k(void __iomem *vbase);

 extern void __init omap_check_revision(void);

--
1.7.0.4

[PATCH-V7 0/3] ARM: OMAP: Make OMAP clocksource source selection runtime

[Tony Lindgren]

* Vaibhav Hiremath <hvaibhav@ti.com> [120503 01:02]:
> Current OMAP code supports couple of clocksource options based
> on compilation flag (CONFIG_OMAP_32K_TIMER). The 32KHz sync-timer
> and a gptimer which can run on 32KHz or system clock (e.g 38.4 MHz)
 
I'll apply these into cleanup-timer branch now that we have the
related hwmod patches merged into devel-hwmod-data.

Regards,

Tony

[PATCH-V7 0/3] ARM: OMAP: Make OMAP clocksource source selection runtime

[Janusz Krzysztofik]

Dnia czwartek, 3 maja 2012 13:28:58 Vaibhav Hiremath pisze:
> Current OMAP code supports couple of clocksource options based
> on compilation flag (CONFIG_OMAP_32K_TIMER). The 32KHz sync-timer
> and a gptimer which can run on 32KHz or system clock (e.g 38.4 MHz)
> 
> This patch series cleans up the existing 32k-sync timer 
implementation,
> movind SoC init code to respective files (mach-omap1/timer32k.c and
> mach-omap2/timer.c) and uses kernel parameter to override the default
> clocksource of "counter_32k", also in order to support some OMAP based
> derivative SoCs like AM33XX which doesn't have 32K sync-timer hardware 
IP,
> adds hwmod lookup for omap2+ devices, and if lookup fails then
> fall back to gp-timer.
> 
> if(use_gptimer_clksrc == true)
> 	gptimer clocksource init;
> else if (counter_32 init == false)
> 	/* Fallback to gptimer */
> 	gptimer clocksource init(;
> 
> With this, we should be able to support multi-omap boot
> including devices with/without 32k-sync timer.
> 
> This patch-series has been boot tested on AM37xEVM platform, it
> would be helpful if somebody help me to validate it on OMAP1/2
> platforms.
> 
> The patches are also available at (based on linux-omap/master) -
> https://github.com/hvaibhav/am335x-linux   32ksync-timer-cleanup

Tried to test this branch, merged into 3.4-rc6, and with my Amstrad 
Delta fixes applied, using my custom Amstrad Delta config, but initially 
failed because an unrelated issue rised to the surface:

|   LD      .tmp_vmlinux1
| arch/arm/mach-omap1/built-in.o: In function `omap1_usb_init':
| lcd_dma.c:(.init.text+0x1420): undefined reference to `ocpi_enable'
| make: *** [.tmp_vmlinux1] Error 1

Apparently introduced with commit 
d3645d39ad0ed9f09535065676ea0ba114f93cdf, "ARM: OMAP1: OHCI: use 
platform_data fn ptr to enable OCPI bus", looks like one or more symbols 
exported by the not linked in arch/arm/mach-omap1/ocpi.o may be missing 
for non-OMAP16xx configs.

Otherwise, if configured with OMAP16xx selected, builds and seems to work 
correctly for me, to the extent possible to verify without physical 
access to the hardware. However, please note that the Amstrad Delta 
doesn't make use of the 32k timer, only mpu_timer.

Thanks,
Janusz

[PATCH-V7 0/3] ARM: OMAP: Make OMAP clocksource source selection runtime

[Paul Walmsley]

Hi Janusz,

On Thu, 10 May 2012, Janusz Krzysztofik wrote:

> Tried to test this branch, merged into 3.4-rc6, and with my Amstrad 
> Delta fixes applied, using my custom Amstrad Delta config, but initially 
> failed because an unrelated issue rised to the surface:
> 
> |   LD      .tmp_vmlinux1
> | arch/arm/mach-omap1/built-in.o: In function `omap1_usb_init':
> | lcd_dma.c:(.init.text+0x1420): undefined reference to `ocpi_enable'
> | make: *** [.tmp_vmlinux1] Error 1
> 
> Apparently introduced with commit 
> d3645d39ad0ed9f09535065676ea0ba114f93cdf, "ARM: OMAP1: OHCI: use 
> platform_data fn ptr to enable OCPI bus", looks like one or more symbols 
> exported by the not linked in arch/arm/mach-omap1/ocpi.o may be missing 
> for non-OMAP16xx configs.

Thanks for the report, I'll send a fix.


- Paul

[PATCH-V7 0/3] ARM: OMAP: Make OMAP clocksource source selection runtime

[Tony Lindgren]

* Janusz Krzysztofik <jmkrzyszt@gmail.com> [120510 14:40]:
> 
> Otherwise, if configured with OMAP16xx selected, builds and seems to work 
> correctly for me, to the extent possible to verify without physical 
> access to the hardware. However, please note that the Amstrad Delta 
> doesn't make use of the 32k timer, only mpu_timer.

OK good to hear, thanks!

Tony

[PATCH-V7 0/3] ARM: OMAP: Make OMAP clocksource source selection runtime

[Paul Walmsley]

Hello Janusz,

On Thu, 10 May 2012, Janusz Krzysztofik wrote:

> Tried to test this branch, merged into 3.4-rc6, and with my Amstrad 
> Delta fixes applied, using my custom Amstrad Delta config, but initially 
> failed because an unrelated issue rised to the surface:
> 
> |   LD      .tmp_vmlinux1
> | arch/arm/mach-omap1/built-in.o: In function `omap1_usb_init':
> | lcd_dma.c:(.init.text+0x1420): undefined reference to `ocpi_enable'
> | make: *** [.tmp_vmlinux1] Error 1
> 
> Apparently introduced with commit 
> d3645d39ad0ed9f09535065676ea0ba114f93cdf, "ARM: OMAP1: OHCI: use 
> platform_data fn ptr to enable OCPI bus", looks like one or more symbols 
> exported by the not linked in arch/arm/mach-omap1/ocpi.o may be missing 
> for non-OMAP16xx configs.

A fix for this is now posted here:

http://marc.info/?l=linux-omap&m=133668898529344&w=2

If you have the chance to test it, that would be great.  Hopefully it 
should be pretty uncontroversial.


- Paul

[PATCH-V7 0/3] ARM: OMAP: Make OMAP clocksource source selection runtime

[Hiremath, Vaibhav]

On Fri, May 11, 2012 at 03:06:48, Janusz Krzysztofik wrote:
> Dnia czwartek, 3 maja 2012 13:28:58 Vaibhav Hiremath pisze:
> > Current OMAP code supports couple of clocksource options based
> > on compilation flag (CONFIG_OMAP_32K_TIMER). The 32KHz sync-timer
> > and a gptimer which can run on 32KHz or system clock (e.g 38.4 MHz)
> > 
> > This patch series cleans up the existing 32k-sync timer 
> implementation,
> > movind SoC init code to respective files (mach-omap1/timer32k.c and
> > mach-omap2/timer.c) and uses kernel parameter to override the default
> > clocksource of "counter_32k", also in order to support some OMAP based
> > derivative SoCs like AM33XX which doesn't have 32K sync-timer hardware 
> IP,
> > adds hwmod lookup for omap2+ devices, and if lookup fails then
> > fall back to gp-timer.
> > 
> > if(use_gptimer_clksrc == true)
> > 	gptimer clocksource init;
> > else if (counter_32 init == false)
> > 	/* Fallback to gptimer */
> > 	gptimer clocksource init(;
> > 
> > With this, we should be able to support multi-omap boot
> > including devices with/without 32k-sync timer.
> > 
> > This patch-series has been boot tested on AM37xEVM platform, it
> > would be helpful if somebody help me to validate it on OMAP1/2
> > platforms.
> > 
> > The patches are also available at (based on linux-omap/master) -
> > https://github.com/hvaibhav/am335x-linux   32ksync-timer-cleanup
> 
> Tried to test this branch, merged into 3.4-rc6, and with my Amstrad 
> Delta fixes applied, using my custom Amstrad Delta config, but initially 
> failed because an unrelated issue rised to the surface:
> 
> |   LD      .tmp_vmlinux1
> | arch/arm/mach-omap1/built-in.o: In function `omap1_usb_init':
> | lcd_dma.c:(.init.text+0x1420): undefined reference to `ocpi_enable'
> | make: *** [.tmp_vmlinux1] Error 1
> 
> Apparently introduced with commit 
> d3645d39ad0ed9f09535065676ea0ba114f93cdf, "ARM: OMAP1: OHCI: use 
> platform_data fn ptr to enable OCPI bus", looks like one or more symbols 
> exported by the not linked in arch/arm/mach-omap1/ocpi.o may be missing 
> for non-OMAP16xx configs.
> 
> Otherwise, if configured with OMAP16xx selected, builds and seems to work 
> correctly for me, to the extent possible to verify without physical 
> access to the hardware. However, please note that the Amstrad Delta 
> doesn't make use of the 32k timer, only mpu_timer.
> 

Thanks Janusz for validating this, really appreciate your help here.

Thanks,
Vaibhav