Merge branch 'fixes-timer' of github.com:jonhunter/linux into omap-for-v3.8/timer

2 files changed, 98 insertions, 51 deletions

diff --git a/arch/arm/plat-omap/dmtimer.c b/arch/arm/plat-omap/dmtimer.c
index 9dca23e4d6b..9deeb3064d3 100644
--- a/arch/arm/plat-omap/dmtimer.c
+++ b/arch/arm/plat-omap/dmtimer.c
@@ -35,6 +35,7 @@
  * 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
+#include <linux/clk.h>
 #include <linux/module.h>
 #include <linux/io.h>
 #include <linux/device.h>
@@ -83,10 +84,6 @@ static void omap_dm_timer_write_reg(struct omap_dm_timer *timer, u32 reg,
 
 static void omap_timer_restore_context(struct omap_dm_timer *timer)
 {
-	if (timer->revision == 1)
-		__raw_writel(timer->context.tistat, timer->sys_stat);
-
-	__raw_writel(timer->context.tisr, timer->irq_stat);
 	omap_dm_timer_write_reg(timer, OMAP_TIMER_WAKEUP_EN_REG,
 				timer->context.twer);
 	omap_dm_timer_write_reg(timer, OMAP_TIMER_COUNTER_REG,
@@ -121,21 +118,13 @@ static void omap_dm_timer_wait_for_reset(struct omap_dm_timer *timer)
 
 static void omap_dm_timer_reset(struct omap_dm_timer *timer)
 {
-	omap_dm_timer_enable(timer);
-	if (timer->pdev->id != 1) {
-		omap_dm_timer_write_reg(timer, OMAP_TIMER_IF_CTRL_REG, 0x06);
-		omap_dm_timer_wait_for_reset(timer);
-	}
-
+	omap_dm_timer_write_reg(timer, OMAP_TIMER_IF_CTRL_REG, 0x06);
+	omap_dm_timer_wait_for_reset(timer);
 	__omap_dm_timer_reset(timer, 0, 0);
-	omap_dm_timer_disable(timer);
-	timer->posted = 1;
 }
 
 int omap_dm_timer_prepare(struct omap_dm_timer *timer)
 {
-	int ret;
-
 	/*
 	 * FIXME: OMAP1 devices do not use the clock framework for dmtimers so
 	 * do not call clk_get() for these devices.
@@ -149,13 +138,15 @@ int omap_dm_timer_prepare(struct omap_dm_timer *timer)
 		}
 	}
 
+	omap_dm_timer_enable(timer);
+
 	if (timer->capability & OMAP_TIMER_NEEDS_RESET)
 		omap_dm_timer_reset(timer);
 
-	ret = omap_dm_timer_set_source(timer, OMAP_TIMER_SRC_32_KHZ);
+	__omap_dm_timer_enable_posted(timer);
+	omap_dm_timer_disable(timer);
 
-	timer->posted = 1;
-	return ret;
+	return omap_dm_timer_set_source(timer, OMAP_TIMER_SRC_32_KHZ);
 }
 
 static inline u32 omap_dm_timer_reserved_systimer(int id)
@@ -449,7 +440,6 @@ int omap_dm_timer_stop(struct omap_dm_timer *timer)
 	 */
 	timer->context.tclr =
 			omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
-	timer->context.tisr = __raw_readl(timer->irq_stat);
 	omap_dm_timer_disable(timer);
 	return 0;
 }
@@ -459,7 +449,7 @@ int omap_dm_timer_set_source(struct omap_dm_timer *timer, int source)
 {
 	int ret;
 	char *parent_name = NULL;
-	struct clk *fclk, *parent;
+	struct clk *parent;
 	struct dmtimer_platform_data *pdata;
 
 	if (unlikely(!timer))
@@ -478,11 +468,8 @@ int omap_dm_timer_set_source(struct omap_dm_timer *timer, int source)
 	if (pdata && pdata->set_timer_src)
 		return pdata->set_timer_src(timer->pdev, source);
 
-	fclk = clk_get(&timer->pdev->dev, "fck");
-	if (IS_ERR_OR_NULL(fclk)) {
-		pr_err("%s: fck not found\n", __func__);
+	if (!timer->fclk)
 		return -EINVAL;
-	}
 
 	switch (source) {
 	case OMAP_TIMER_SRC_SYS_CLK:
@@ -501,18 +488,15 @@ int omap_dm_timer_set_source(struct omap_dm_timer *timer, int source)
 	parent = clk_get(&timer->pdev->dev, parent_name);
 	if (IS_ERR_OR_NULL(parent)) {
 		pr_err("%s: %s not found\n", __func__, parent_name);
-		ret = -EINVAL;
-		goto out;
+		return -EINVAL;
 	}
 
-	ret = clk_set_parent(fclk, parent);
+	ret = clk_set_parent(timer->fclk, parent);
 	if (IS_ERR_VALUE(ret))
 		pr_err("%s: failed to set %s as parent\n", __func__,
 			parent_name);
 
 	clk_put(parent);
-out:
-	clk_put(fclk);
 
 	return ret;
 }
@@ -595,8 +579,8 @@ int omap_dm_timer_set_match(struct omap_dm_timer *timer, int enable,
 		l |= OMAP_TIMER_CTRL_CE;
 	else
 		l &= ~OMAP_TIMER_CTRL_CE;
-	omap_dm_timer_write_reg(timer, OMAP_TIMER_CTRL_REG, l);
 	omap_dm_timer_write_reg(timer, OMAP_TIMER_MATCH_REG, match);
+	omap_dm_timer_write_reg(timer, OMAP_TIMER_CTRL_REG, l);
 
 	/* Save the context */
 	timer->context.tclr = l;
@@ -672,6 +656,37 @@ int omap_dm_timer_set_int_enable(struct omap_dm_timer *timer,
 }
 EXPORT_SYMBOL_GPL(omap_dm_timer_set_int_enable);
 
+/**
+ * omap_dm_timer_set_int_disable - disable timer interrupts
+ * @timer:	pointer to timer handle
+ * @mask:	bit mask of interrupts to be disabled
+ *
+ * Disables the specified timer interrupts for a timer.
+ */
+int omap_dm_timer_set_int_disable(struct omap_dm_timer *timer, u32 mask)
+{
+	u32 l = mask;
+
+	if (unlikely(!timer))
+		return -EINVAL;
+
+	omap_dm_timer_enable(timer);
+
+	if (timer->revision == 1)
+		l = __raw_readl(timer->irq_ena) & ~mask;
+
+	__raw_writel(l, timer->irq_dis);
+	l = omap_dm_timer_read_reg(timer, OMAP_TIMER_WAKEUP_EN_REG) & ~mask;
+	omap_dm_timer_write_reg(timer, OMAP_TIMER_WAKEUP_EN_REG, l);
+
+	/* Save the context */
+	timer->context.tier &= ~mask;
+	timer->context.twer &= ~mask;
+	omap_dm_timer_disable(timer);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(omap_dm_timer_set_int_disable);
+
 unsigned int omap_dm_timer_read_status(struct omap_dm_timer *timer)
 {
 	unsigned int l;
@@ -693,8 +708,7 @@ int omap_dm_timer_write_status(struct omap_dm_timer *timer, unsigned int value)
 		return -EINVAL;
 
 	__omap_dm_timer_write_status(timer, value);
-	/* Save the context */
-	timer->context.tisr = value;
+
 	return 0;
 }
 EXPORT_SYMBOL_GPL(omap_dm_timer_write_status);
@@ -797,6 +811,7 @@ static int __devinit omap_dm_timer_probe(struct platform_device *pdev)
 			timer->capability |= OMAP_TIMER_SECURE;
 	} else {
 		timer->id = pdev->id;
+		timer->errata = pdata->timer_errata;
 		timer->capability = pdata->timer_capability;
 		timer->reserved = omap_dm_timer_reserved_systimer(timer->id);
 		timer->get_context_loss_count = pdata->get_context_loss_count;
diff --git a/arch/arm/plat-omap/include/plat/dmtimer.h b/arch/arm/plat-omap/include/plat/dmtimer.h
index f8943c8f9db..05a36e16f3f 100644
--- a/arch/arm/plat-omap/include/plat/dmtimer.h
+++ b/arch/arm/plat-omap/include/plat/dmtimer.h
@@ -32,7 +32,6 @@
  * 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
-#include <linux/clk.h>
 #include <linux/delay.h>
 #include <linux/io.h>
 #include <linux/platform_device.h>
@@ -55,6 +54,10 @@
 #define OMAP_TIMER_TRIGGER_OVERFLOW		0x01
 #define OMAP_TIMER_TRIGGER_OVERFLOW_AND_COMPARE	0x02
 
+/* posted mode types */
+#define OMAP_TIMER_NONPOSTED			0x00
+#define OMAP_TIMER_POSTED			0x01
+
 /* timer capabilities used in hwmod database */
 #define OMAP_TIMER_SECURE				0x80000000
 #define OMAP_TIMER_ALWON				0x40000000
@@ -62,6 +65,16 @@
 #define OMAP_TIMER_NEEDS_RESET				0x10000000
 #define OMAP_TIMER_HAS_DSP_IRQ				0x08000000
 
+/*
+ * timer errata flags
+ *
+ * Errata i103/i767 impacts all OMAP3/4/5 devices including AM33xx. This
+ * errata prevents us from using posted mode on these devices, unless the
+ * timer counter register is never read. For more details please refer to
+ * the OMAP3/4/5 errata documents.
+ */
+#define OMAP_TIMER_ERRATA_I103_I767			0x80000000
+
 struct omap_timer_capability_dev_attr {
 	u32 timer_capability;
 };
@@ -70,8 +83,6 @@ struct omap_dm_timer;
 
 struct timer_regs {
 	u32 tidr;
-	u32 tistat;
-	u32 tisr;
 	u32 tier;
 	u32 twer;
 	u32 tclr;
@@ -93,6 +104,7 @@ struct timer_regs {
 struct dmtimer_platform_data {
 	/* set_timer_src - Only used for OMAP1 devices */
 	int (*set_timer_src)(struct platform_device *pdev, int source);
+	u32 timer_errata;
 	u32 timer_capability;
 	int (*get_context_loss_count)(struct device *);
 };
@@ -122,6 +134,7 @@ int omap_dm_timer_set_pwm(struct omap_dm_timer *timer, int def_on, int toggle, i
 int omap_dm_timer_set_prescaler(struct omap_dm_timer *timer, int prescaler);
 
 int omap_dm_timer_set_int_enable(struct omap_dm_timer *timer, unsigned int value);
+int omap_dm_timer_set_int_disable(struct omap_dm_timer *timer, u32 mask);
 
 unsigned int omap_dm_timer_read_status(struct omap_dm_timer *timer);
 int omap_dm_timer_write_status(struct omap_dm_timer *timer, unsigned int value);
@@ -269,6 +282,7 @@ struct omap_dm_timer {
 	int ctx_loss_count;
 	int revision;
 	u32 capability;
+	u32 errata;
 	struct platform_device *pdev;
 	struct list_head node;
 };
@@ -307,7 +321,7 @@ static inline void __omap_dm_timer_init_regs(struct omap_dm_timer *timer)
 				OMAP_TIMER_V1_SYS_STAT_OFFSET;
 		timer->irq_stat = timer->io_base + OMAP_TIMER_V1_STAT_OFFSET;
 		timer->irq_ena = timer->io_base + OMAP_TIMER_V1_INT_EN_OFFSET;
-		timer->irq_dis = NULL;
+		timer->irq_dis = timer->io_base + OMAP_TIMER_V1_INT_EN_OFFSET;
 		timer->pend = timer->io_base + _OMAP_TIMER_WRITE_PEND_OFFSET;
 		timer->func_base = timer->io_base;
 	} else {
@@ -340,28 +354,46 @@ static inline void __omap_dm_timer_reset(struct omap_dm_timer *timer,
 		l |= 1 << 2;
 
 	__raw_writel(l, timer->io_base + OMAP_TIMER_OCP_CFG_OFFSET);
-
-	/* Match hardware reset default of posted mode */
-	__omap_dm_timer_write(timer, OMAP_TIMER_IF_CTRL_REG,
-					OMAP_TIMER_CTRL_POSTED, 0);
 }
 
-static inline int __omap_dm_timer_set_source(struct clk *timer_fck,
-						struct clk *parent)
+/*
+ * __omap_dm_timer_enable_posted - enables write posted mode
+ * @timer:      pointer to timer instance handle
+ *
+ * Enables the write posted mode for the timer. When posted mode is enabled
+ * writes to certain timer registers are immediately acknowledged by the
+ * internal bus and hence prevents stalling the CPU waiting for the write to
+ * complete. Enabling this feature can improve performance for writing to the
+ * timer registers.
+ */
+static inline void __omap_dm_timer_enable_posted(struct omap_dm_timer *timer)
 {
-	int ret;
+	if (timer->posted)
+		return;
 
-	clk_disable(timer_fck);
-	ret = clk_set_parent(timer_fck, parent);
-	clk_enable(timer_fck);
+	if (timer->errata & OMAP_TIMER_ERRATA_I103_I767)
+		return;
 
-	/*
-	 * When the functional clock disappears, too quick writes seem
-	 * to cause an abort. XXX Is this still necessary?
-	 */
-	__delay(300000);
+	__omap_dm_timer_write(timer, OMAP_TIMER_IF_CTRL_REG,
+			      OMAP_TIMER_CTRL_POSTED, 0);
+	timer->context.tsicr = OMAP_TIMER_CTRL_POSTED;
+	timer->posted = OMAP_TIMER_POSTED;
+}
 
-	return ret;
+/**
+ * __omap_dm_timer_override_errata - override errata flags for a timer
+ * @timer:      pointer to timer handle
+ * @errata:	errata flags to be ignored
+ *
+ * For a given timer, override a timer errata by clearing the flags
+ * specified by the errata argument. A specific erratum should only be
+ * overridden for a timer if the timer is used in such a way the erratum
+ * has no impact.
+ */
+static inline void __omap_dm_timer_override_errata(struct omap_dm_timer *timer,
+						   u32 errata)
+{
+	timer->errata &= ~errata;
 }
 
 static inline void __omap_dm_timer_stop(struct omap_dm_timer *timer,