[ARM] 4013/1: clocksource driver for netx

Add a clocksource driver for netx systems

Signed-off-by: Luotao Fu <lfu@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 30 insertions, 12 deletions

diff --git a/arch/arm/mach-netx/time.c b/arch/arm/mach-netx/time.c
index 0993336c0b55..5773b55ef4a6 100644
--- a/arch/arm/mach-netx/time.c
+++ b/arch/arm/mach-netx/time.c
@@ -19,6 +19,8 @@
 
 #include <linux/init.h>
 #include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/clocksource.h>
 
 #include <asm/hardware.h>
 #include <asm/io.h>
@@ -26,15 +28,6 @@
 #include <asm/arch/netx-regs.h>
 
 /*
- * Returns number of us since last clock interrupt.  Note that interrupts
- * will have been disabled by do_gettimeoffset()
- */
-static unsigned long netx_gettimeoffset(void)
-{
-        return readl(NETX_GPIO_COUNTER_CURRENT(0)) / 100;
-}
-
-/*
  * IRQ handler for the timer
  */
 static irqreturn_t
@@ -43,6 +36,7 @@ netx_timer_interrupt(int irq, void *dev_id)
         write_seqlock(&xtime_lock);
 
         timer_tick();
+
         write_sequnlock(&xtime_lock);
 
         /* acknowledge interrupt */
@@ -51,13 +45,26 @@ netx_timer_interrupt(int irq, void *dev_id)
         return IRQ_HANDLED;
 }
 
-
 static struct irqaction netx_timer_irq = {
         .name           = "NetX Timer Tick",
         .flags          = IRQF_DISABLED | IRQF_TIMER,
         .handler        = netx_timer_interrupt,
 };
 
+cycle_t netx_get_cycles(void)
+{
+        return readl(NETX_GPIO_COUNTER_CURRENT(1));
+}
+
+static struct clocksource clocksource_netx = {
+        .name           = "netx_timer",
+        .rating         = 200,
+        .read           = netx_get_cycles,
+        .mask           = CLOCKSOURCE_MASK(32),
+        .shift          = 20,
+        .is_continuous  = 1,
+};
+
 /*
  * Set up timer interrupt
  */
@@ -80,9 +87,20 @@ static void __init netx_timer_init(void)
                 NETX_GPIO_COUNTER_CTRL(0));
 
         setup_irq(NETX_IRQ_TIMER0, &netx_timer_irq);
+
+        /* Setup timer one for clocksource */
+        writel(0, NETX_GPIO_COUNTER_CTRL(1));
+        writel(0, NETX_GPIO_COUNTER_CURRENT(1));
+        writel(0xFFFFFFFF, NETX_GPIO_COUNTER_MAX(1));
+
+        writel(NETX_GPIO_COUNTER_CTRL_RUN,
+                NETX_GPIO_COUNTER_CTRL(1));
+
+        clocksource_netx.mult =
+                clocksource_hz2mult(CLOCK_TICK_RATE, clocksource_netx.shift);
+        clocksource_register(&clocksource_netx);
 }
 
 struct sys_timer netx_timer = {
-        .init           = netx_timer_init,
-        .offset         = netx_gettimeoffset,
+        .init           = netx_timer_init,
 };