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authorTony Lindgren <tony@atomide.com>2012-11-13 13:52:38 -0800
committerTony Lindgren <tony@atomide.com>2012-11-13 13:52:38 -0800
commit9dc57643738f9fbe45c10cc062903d5dfda5bdd9 (patch)
tree1579e10fe2cf0b5473080c74e1184976372df8f2 /arch/arm/plat-omap/include/plat/dmtimer.h
parentd308ba50a1234b299a00e63a95e61fdeb2f1a2df (diff)
parentb1538832191d59e29b1077e64cf416a7617b45bc (diff)
Merge branch 'fixes-timer' of github.com:jonhunter/linux into omap-for-v3.8/timer
Diffstat (limited to 'arch/arm/plat-omap/include/plat/dmtimer.h')
-rw-r--r--arch/arm/plat-omap/include/plat/dmtimer.h72
1 files changed, 52 insertions, 20 deletions
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,