1 files changed, 97 insertions, 19 deletions

diff --git a/drivers/clocksource/sh_cmt.c b/drivers/clocksource/sh_cmt.c
index 1c92c39a53aa..cf56a2af5fe1 100644
--- a/drivers/clocksource/sh_cmt.c
+++ b/drivers/clocksource/sh_cmt.c
@@ -18,7 +18,6 @@
  */
 
 #include <linux/init.h>
-#include <linux/bootmem.h>
 #include <linux/platform_device.h>
 #include <linux/spinlock.h>
 #include <linux/interrupt.h>
@@ -29,7 +28,7 @@
 #include <linux/err.h>
 #include <linux/clocksource.h>
 #include <linux/clockchips.h>
-#include <linux/sh_cmt.h>
+#include <linux/sh_timer.h>
 
 struct sh_cmt_priv {
         void __iomem *mapbase;
@@ -47,6 +46,7 @@ struct sh_cmt_priv {
         unsigned long rate;
         spinlock_t lock;
         struct clock_event_device ced;
+        struct clocksource cs;
         unsigned long total_cycles;
 };
 
@@ -59,7 +59,7 @@ static DEFINE_SPINLOCK(sh_cmt_lock);
 
 static inline unsigned long sh_cmt_read(struct sh_cmt_priv *p, int reg_nr)
 {
-        struct sh_cmt_config *cfg = p->pdev->dev.platform_data;
+        struct sh_timer_config *cfg = p->pdev->dev.platform_data;
         void __iomem *base = p->mapbase;
         unsigned long offs;
 
@@ -83,7 +83,7 @@ static inline unsigned long sh_cmt_read(struct sh_cmt_priv *p, int reg_nr)
 static inline void sh_cmt_write(struct sh_cmt_priv *p, int reg_nr,
                                 unsigned long value)
 {
-        struct sh_cmt_config *cfg = p->pdev->dev.platform_data;
+        struct sh_timer_config *cfg = p->pdev->dev.platform_data;
         void __iomem *base = p->mapbase;
         unsigned long offs;
 
@@ -110,23 +110,28 @@ static unsigned long sh_cmt_get_counter(struct sh_cmt_priv *p,
                                         int *has_wrapped)
 {
         unsigned long v1, v2, v3;
+        int o1, o2;
+
+        o1 = sh_cmt_read(p, CMCSR) & p->overflow_bit;
 
         /* Make sure the timer value is stable. Stolen from acpi_pm.c */
         do {
+                o2 = o1;
                 v1 = sh_cmt_read(p, CMCNT);
                 v2 = sh_cmt_read(p, CMCNT);
                 v3 = sh_cmt_read(p, CMCNT);
-        } while (unlikely((v1 > v2 && v1 < v3) || (v2 > v3 && v2 < v1)
-                          || (v3 > v1 && v3 < v2)));
+                o1 = sh_cmt_read(p, CMCSR) & p->overflow_bit;
+        } while (unlikely((o1 != o2) || (v1 > v2 && v1 < v3)
+                          || (v2 > v3 && v2 < v1) || (v3 > v1 && v3 < v2)));
 
-        *has_wrapped = sh_cmt_read(p, CMCSR) & p->overflow_bit;
+        *has_wrapped = o1;
         return v2;
 }
 
 
 static void sh_cmt_start_stop_ch(struct sh_cmt_priv *p, int start)
 {
-        struct sh_cmt_config *cfg = p->pdev->dev.platform_data;
+        struct sh_timer_config *cfg = p->pdev->dev.platform_data;
         unsigned long flags, value;
 
         /* start stop register shared by multiple timer channels */
@@ -144,7 +149,7 @@ static void sh_cmt_start_stop_ch(struct sh_cmt_priv *p, int start)
 
 static int sh_cmt_enable(struct sh_cmt_priv *p, unsigned long *rate)
 {
-        struct sh_cmt_config *cfg = p->pdev->dev.platform_data;
+        struct sh_timer_config *cfg = p->pdev->dev.platform_data;
         int ret;
 
         /* enable clock */
@@ -153,16 +158,18 @@ static int sh_cmt_enable(struct sh_cmt_priv *p, unsigned long *rate)
                 pr_err("sh_cmt: cannot enable clock \"%s\"\n", cfg->clk);
                 return ret;
         }
-        *rate = clk_get_rate(p->clk) / 8;
 
         /* make sure channel is disabled */
         sh_cmt_start_stop_ch(p, 0);
 
         /* configure channel, periodic mode and maximum timeout */
-        if (p->width == 16)
-                sh_cmt_write(p, CMCSR, 0);
-        else
+        if (p->width == 16) {
+                *rate = clk_get_rate(p->clk) / 512;
+                sh_cmt_write(p, CMCSR, 0x43);
+        } else {
+                *rate = clk_get_rate(p->clk) / 8;
                 sh_cmt_write(p, CMCSR, 0x01a4);
+        }
 
         sh_cmt_write(p, CMCOR, 0xffffffff);
         sh_cmt_write(p, CMCNT, 0);
@@ -376,6 +383,68 @@ static void sh_cmt_stop(struct sh_cmt_priv *p, unsigned long flag)
         spin_unlock_irqrestore(&p->lock, flags);
 }
 
+static struct sh_cmt_priv *cs_to_sh_cmt(struct clocksource *cs)
+{
+        return container_of(cs, struct sh_cmt_priv, cs);
+}
+
+static cycle_t sh_cmt_clocksource_read(struct clocksource *cs)
+{
+        struct sh_cmt_priv *p = cs_to_sh_cmt(cs);
+        unsigned long flags, raw;
+        unsigned long value;
+        int has_wrapped;
+
+        spin_lock_irqsave(&p->lock, flags);
+        value = p->total_cycles;
+        raw = sh_cmt_get_counter(p, &has_wrapped);
+
+        if (unlikely(has_wrapped))
+                raw += p->match_value;
+        spin_unlock_irqrestore(&p->lock, flags);
+
+        return value + raw;
+}
+
+static int sh_cmt_clocksource_enable(struct clocksource *cs)
+{
+        struct sh_cmt_priv *p = cs_to_sh_cmt(cs);
+        int ret;
+
+        p->total_cycles = 0;
+
+        ret = sh_cmt_start(p, FLAG_CLOCKSOURCE);
+        if (ret)
+                return ret;
+
+        /* TODO: calculate good shift from rate and counter bit width */
+        cs->shift = 0;
+        cs->mult = clocksource_hz2mult(p->rate, cs->shift);
+        return 0;
+}
+
+static void sh_cmt_clocksource_disable(struct clocksource *cs)
+{
+        sh_cmt_stop(cs_to_sh_cmt(cs), FLAG_CLOCKSOURCE);
+}
+
+static int sh_cmt_register_clocksource(struct sh_cmt_priv *p,
+                                       char *name, unsigned long rating)
+{
+        struct clocksource *cs = &p->cs;
+
+        cs->name = name;
+        cs->rating = rating;
+        cs->read = sh_cmt_clocksource_read;
+        cs->enable = sh_cmt_clocksource_enable;
+        cs->disable = sh_cmt_clocksource_disable;
+        cs->mask = CLOCKSOURCE_MASK(sizeof(unsigned long) * 8);
+        cs->flags = CLOCK_SOURCE_IS_CONTINUOUS;
+        pr_info("sh_cmt: %s used as clock source\n", cs->name);
+        clocksource_register(cs);
+        return 0;
+}
+
 static struct sh_cmt_priv *ced_to_sh_cmt(struct clock_event_device *ced)
 {
         return container_of(ced, struct sh_cmt_priv, ced);
@@ -468,9 +537,9 @@ static void sh_cmt_register_clockevent(struct sh_cmt_priv *p,
         clockevents_register_device(ced);
 }
 
-int sh_cmt_register(struct sh_cmt_priv *p, char *name,
-                    unsigned long clockevent_rating,
-                    unsigned long clocksource_rating)
+static int sh_cmt_register(struct sh_cmt_priv *p, char *name,
+                           unsigned long clockevent_rating,
+                           unsigned long clocksource_rating)
 {
         if (p->width == (sizeof(p->max_match_value) * 8))
                 p->max_match_value = ~0;
@@ -483,12 +552,15 @@ int sh_cmt_register(struct sh_cmt_priv *p, char *name,
         if (clockevent_rating)
                 sh_cmt_register_clockevent(p, name, clockevent_rating);
 
+        if (clocksource_rating)
+                sh_cmt_register_clocksource(p, name, clocksource_rating);
+
         return 0;
 }
 
 static int sh_cmt_setup(struct sh_cmt_priv *p, struct platform_device *pdev)
 {
-        struct sh_cmt_config *cfg = pdev->dev.platform_data;
+        struct sh_timer_config *cfg = pdev->dev.platform_data;
         struct resource *res;
         int irq, ret;
         ret = -ENXIO;
@@ -545,7 +617,7 @@ static int sh_cmt_setup(struct sh_cmt_priv *p, struct platform_device *pdev)
         if (resource_size(res) == 6) {
                 p->width = 16;
                 p->overflow_bit = 0x80;
-                p->clear_bits = ~0xc0;
+                p->clear_bits = ~0x80;
         } else {
                 p->width = 32;
                 p->overflow_bit = 0x8000;
@@ -566,8 +638,14 @@ static int sh_cmt_setup(struct sh_cmt_priv *p, struct platform_device *pdev)
 static int __devinit sh_cmt_probe(struct platform_device *pdev)
 {
         struct sh_cmt_priv *p = platform_get_drvdata(pdev);
+        struct sh_timer_config *cfg = pdev->dev.platform_data;
         int ret;
 
+        if (p) {
+                pr_info("sh_cmt: %s kept as earlytimer\n", cfg->name);
+                return 0;
+        }
+
         p = kmalloc(sizeof(*p), GFP_KERNEL);
         if (p == NULL) {
                 dev_err(&pdev->dev, "failed to allocate driver data\n");
@@ -577,7 +655,6 @@ static int __devinit sh_cmt_probe(struct platform_device *pdev)
         ret = sh_cmt_setup(p, pdev);
         if (ret) {
                 kfree(p);
-
                 platform_set_drvdata(pdev, NULL);
         }
         return ret;
@@ -606,6 +683,7 @@ static void __exit sh_cmt_exit(void)
         platform_driver_unregister(&sh_cmt_device_driver);
 }
 
+early_platform_init("earlytimer", &sh_cmt_device_driver);
 module_init(sh_cmt_init);
 module_exit(sh_cmt_exit);