Revert "dw_apb_timer_of.c: Remove parts that were picoxcell-specific"

This reverts commit 55a68c2.

In order to avoid a collision with dw_apb_timer changes in
the arm-soc tree, revert this change.

I'm leaving it to the arm-soc folks to sort out if they want
to keep the other side of the collision or if they're just going
to back it all out and try again during the next release cycle.

Reported-by: Dinh Nguyen <dinguyen@altera.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>

arch/arm/mach-picoxcell/common.h

@@ -12,4 +12,6 @@
 
 #include <asm/mach/time.h>
 
+extern void dw_apb_timer_init(void);
+
 #endif /* __PICOXCELL_COMMON_H__ */

drivers/clocksource/dw_apb_timer.c

@@ -21,6 +21,12 @@
 #define APBT_MIN_PERIOD			4
 #define APBT_MIN_DELTA_USEC		200
 
+#define APBTMR_N_LOAD_COUNT		0x00
+#define APBTMR_N_CURRENT_VALUE		0x04
+#define APBTMR_N_CONTROL		0x08
+#define APBTMR_N_EOI			0x0c
+#define APBTMR_N_INT_STATUS		0x10
+
 #define APBTMRS_INT_STATUS		0xa0
 #define APBTMRS_EOI			0xa4
 #define APBTMRS_RAW_INT_STATUS		0xa8

drivers/clocksource/dw_apb_timer_of.c

@@ -55,15 +55,6 @@ static void add_clockevent(struct device_node *event_timer)
 	dw_apb_clockevent_register(ced);
 }
 
-static void __iomem *sched_io_base;
-
-/* This is actually same as __apbt_read_clocksource(), but with
-   different interface */
-static u32 read_sched_clock_sptimer(void)
-{
-	return ~__raw_readl(sched_io_base + APBTMR_N_CURRENT_VALUE);
-}
-
 static void add_clocksource(struct device_node *source_timer)
 {
 	void __iomem *iobase;
@@ -78,27 +69,41 @@ static void add_clocksource(struct device_node *source_timer)
 
 	dw_apb_clocksource_start(cs);
 	dw_apb_clocksource_register(cs);
+}
 
-	sched_io_base = iobase;
-	setup_sched_clock(read_sched_clock_sptimer, 32, rate);
+static void __iomem *sched_io_base;
+
+static u32 read_sched_clock(void)
+{
+	return __raw_readl(sched_io_base);
 }
 
-static const struct of_device_id osctimer_ids[] __initconst = {
-	{ .compatible = "picochip,pc3x2-timer" },
-	{ .compatible = "snps,dw-apb-timer-osc" },
+static const struct of_device_id sptimer_ids[] __initconst = {
+	{ .compatible = "picochip,pc3x2-rtc" },
 	{ .compatible = "snps,dw-apb-timer-sp" },
-	{  /* Sentinel */ },
+	{ /* Sentinel */ },
 };
 
-/*
-   You don't have to use dw_apb_timer for scheduler clock,
-   this should also work fine on arm:
+static void init_sched_clock(void)
+{
+	struct device_node *sched_timer;
+	u32 rate;
 
-  twd_local_timer_of_register();
-  arch_timer_of_register();
-  arch_timer_sched_clock_init();
-*/
+	sched_timer = of_find_matching_node(NULL, sptimer_ids);
+	if (!sched_timer)
+		panic("No RTC for sched clock to use");
 
+	timer_get_base_and_rate(sched_timer, &sched_io_base, &rate);
+	of_node_put(sched_timer);
+
+	setup_sched_clock(read_sched_clock, 32, rate);
+}
+
+static const struct of_device_id osctimer_ids[] __initconst = {
+	{ .compatible = "picochip,pc3x2-timer" },
+	{ .compatible = "snps,dw-apb-timer-osc" },
+	{},
+};
 
 void __init dw_apb_timer_init(void)
 {
@@ -114,6 +119,7 @@ void __init dw_apb_timer_init(void)
 		panic("No timer for clocksource");
 	add_clocksource(source_timer);
 
-	of_node_put(event_timer);
 	of_node_put(source_timer);
+
+	init_sched_clock();
 }

include/linux/dw_apb_timer.h

@@ -17,12 +17,6 @@
 #include <linux/clocksource.h>
 #include <linux/interrupt.h>
 
-#define APBTMR_N_LOAD_COUNT		0x00
-#define APBTMR_N_CURRENT_VALUE		0x04
-#define APBTMR_N_CONTROL		0x08
-#define APBTMR_N_EOI			0x0c
-#define APBTMR_N_INT_STATUS		0x10
-
 #define APBTMRS_REG_SIZE       0x14
 
 struct dw_apb_timer {