iop: enable generic time

This updates the IOP platform to use the kernel's generic time
framework. With clockevent support in place, this reduces to
selecting GENERIC_TIME and removing the platform's private timer
->offset() operation (iop_gettimeoffset).

Tested on n2100, compile-tested for all plat-iop machines.

Signed-off-by: Mikael Pettersson <mikpe@it.uu.se>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index e732fcc..455284e 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -811,6 +811,7 @@
 config PLAT_IOP
 	bool
 	select GENERIC_CLOCKEVENTS
+	select GENERIC_TIME
 
 config PLAT_ORION
 	bool
diff --git a/arch/arm/include/asm/hardware/iop3xx.h b/arch/arm/include/asm/hardware/iop3xx.h
index 34601b9..5daea29 100644
--- a/arch/arm/include/asm/hardware/iop3xx.h
+++ b/arch/arm/include/asm/hardware/iop3xx.h
@@ -234,7 +234,6 @@
 void iop3xx_map_io(void);
 void iop_init_cp6_handler(void);
 void iop_init_time(unsigned long tickrate);
-unsigned long iop_gettimeoffset(void);
 
 static inline u32 read_tmr0(void)
 {
diff --git a/arch/arm/mach-iop13xx/include/mach/time.h b/arch/arm/mach-iop13xx/include/mach/time.h
index b2fb17b..f1c00d6 100644
--- a/arch/arm/mach-iop13xx/include/mach/time.h
+++ b/arch/arm/mach-iop13xx/include/mach/time.h
@@ -20,7 +20,6 @@
 #define IOP13XX_CORE_FREQ_1200		(5 << 16)
 
 void iop_init_time(unsigned long tickrate);
-unsigned long iop_gettimeoffset(void);
 
 static inline unsigned long iop13xx_core_freq(void)
 {
diff --git a/arch/arm/mach-iop13xx/iq81340mc.c b/arch/arm/mach-iop13xx/iq81340mc.c
index 5051c03..f91f315 100644
--- a/arch/arm/mach-iop13xx/iq81340mc.c
+++ b/arch/arm/mach-iop13xx/iq81340mc.c
@@ -87,7 +87,6 @@
 
 static struct sys_timer iq81340mc_timer = {
        .init       = iq81340mc_timer_init,
-       .offset     = iop_gettimeoffset,
 };
 
 MACHINE_START(IQ81340MC, "Intel IQ81340MC")
diff --git a/arch/arm/mach-iop13xx/iq81340sc.c b/arch/arm/mach-iop13xx/iq81340sc.c
index bc44307..ddb7a34 100644
--- a/arch/arm/mach-iop13xx/iq81340sc.c
+++ b/arch/arm/mach-iop13xx/iq81340sc.c
@@ -89,7 +89,6 @@
 
 static struct sys_timer iq81340sc_timer = {
        .init       = iq81340sc_timer_init,
-       .offset     = iop_gettimeoffset,
 };
 
 MACHINE_START(IQ81340SC, "Intel IQ81340SC")
diff --git a/arch/arm/mach-iop32x/em7210.c b/arch/arm/mach-iop32x/em7210.c
index 3ad4696..2bef9b6 100644
--- a/arch/arm/mach-iop32x/em7210.c
+++ b/arch/arm/mach-iop32x/em7210.c
@@ -42,7 +42,6 @@
 
 static struct sys_timer em7210_timer = {
 	.init		= em7210_timer_init,
-	.offset		= iop_gettimeoffset,
 };
 
 /*
diff --git a/arch/arm/mach-iop32x/glantank.c b/arch/arm/mach-iop32x/glantank.c
index a9c2dfd..93370a4 100644
--- a/arch/arm/mach-iop32x/glantank.c
+++ b/arch/arm/mach-iop32x/glantank.c
@@ -47,7 +47,6 @@
 
 static struct sys_timer glantank_timer = {
 	.init		= glantank_timer_init,
-	.offset		= iop_gettimeoffset,
 };
 
 
diff --git a/arch/arm/mach-iop32x/iq31244.c b/arch/arm/mach-iop32x/iq31244.c
index dd1cd99..a7a08dd 100644
--- a/arch/arm/mach-iop32x/iq31244.c
+++ b/arch/arm/mach-iop32x/iq31244.c
@@ -78,7 +78,6 @@
 
 static struct sys_timer iq31244_timer = {
 	.init		= iq31244_timer_init,
-	.offset		= iop_gettimeoffset,
 };
 
 
diff --git a/arch/arm/mach-iop32x/iq80321.c b/arch/arm/mach-iop32x/iq80321.c
index fbe2779..0200f80 100644
--- a/arch/arm/mach-iop32x/iq80321.c
+++ b/arch/arm/mach-iop32x/iq80321.c
@@ -46,7 +46,6 @@
 
 static struct sys_timer iq80321_timer = {
 	.init		= iq80321_timer_init,
-	.offset		= iop_gettimeoffset,
 };
 
 
diff --git a/arch/arm/mach-iop32x/n2100.c b/arch/arm/mach-iop32x/n2100.c
index d2e4278..2a5c637 100644
--- a/arch/arm/mach-iop32x/n2100.c
+++ b/arch/arm/mach-iop32x/n2100.c
@@ -53,7 +53,6 @@
 
 static struct sys_timer n2100_timer = {
 	.init		= n2100_timer_init,
-	.offset		= iop_gettimeoffset,
 };
 
 
diff --git a/arch/arm/mach-iop33x/iq80331.c b/arch/arm/mach-iop33x/iq80331.c
index d51e10c..394e95a 100644
--- a/arch/arm/mach-iop33x/iq80331.c
+++ b/arch/arm/mach-iop33x/iq80331.c
@@ -48,7 +48,6 @@
 
 static struct sys_timer iq80331_timer = {
 	.init		= iq80331_timer_init,
-	.offset		= iop_gettimeoffset,
 };
 
 
diff --git a/arch/arm/mach-iop33x/iq80332.c b/arch/arm/mach-iop33x/iq80332.c
index 92fb44c..a40badf 100644
--- a/arch/arm/mach-iop33x/iq80332.c
+++ b/arch/arm/mach-iop33x/iq80332.c
@@ -48,7 +48,6 @@
 
 static struct sys_timer iq80332_timer = {
 	.init		= iq80332_timer_init,
-	.offset		= iop_gettimeoffset,
 };
 
 
diff --git a/arch/arm/plat-iop/time.c b/arch/arm/plat-iop/time.c
index a550e96..aaaef3b 100644
--- a/arch/arm/plat-iop/time.c
+++ b/arch/arm/plat-iop/time.c
@@ -140,33 +140,6 @@
 	       ce->name, ce->shift, ce->mult);
 }
 
-static unsigned long ticks_per_usec;
-static unsigned long next_jiffy_time;
-
-unsigned long iop_gettimeoffset(void)
-{
-	unsigned long offset, temp;
-
-	/* enable cp6, if necessary, to avoid taking the overhead of an
-	 * undefined instruction trap
-	 */
-	asm volatile (
-	"mrc	p15, 0, %0, c15, c1, 0\n\t"
-	"tst	%0, #(1 << 6)\n\t"
-	"orreq	%0, %0, #(1 << 6)\n\t"
-	"mcreq	p15, 0, %0, c15, c1, 0\n\t"
-#ifdef CONFIG_CPU_XSCALE
-	"mrceq	p15, 0, %0, c15, c1, 0\n\t"
-	"moveq	%0, %0\n\t"
-	"subeq	pc, pc, #4\n\t"
-#endif
-	: "=r"(temp) : : "cc");
-
-	offset = next_jiffy_time - read_tcr1();
-
-	return offset / ticks_per_usec;
-}
-
 static irqreturn_t
 iop_timer_interrupt(int irq, void *dev_id)
 {
@@ -196,8 +169,6 @@
 	u32 timer_ctl;
 
 	ticks_per_jiffy = DIV_ROUND_CLOSEST(tick_rate, HZ);
-	ticks_per_usec = tick_rate / 1000000;
-	next_jiffy_time = 0xffffffff;
 	iop_tick_rate = tick_rate;
 
 	timer_ctl = IOP_TMR_EN | IOP_TMR_PRIVILEGED |