ARM: OMAP: Clean-up dmtimer reset code

Only OMAP1 devices use the omap_dm_timer_reset() and so require the
omap_dm_timer_wait_for_reset() and __omap_dm_timer_reset() functions.
Therefore combine these into a single function called omap_dm_timer_reset()
and simplify the code.

The omap_dm_timer_reset() function is now the only place that is using the
omap_dm_timer structure member "sys_stat". Therefore, remove this member and
just use the register offset definition to simplify and clean-up the code. The
TISTAT register is only present on revision 1 timers and so check for this in
the omap_dm_timer_reset() function.

Please note that for OMAP1 devices, the TIOCP_CFG register does not have the
clock-activity field and so when we reset the timer for an OMAP1 device we
only need to configure the idle-mode field in the TIOCP_CFG register.

Signed-off-by: Jon Hunter <jon-hunter@ti.com>

2 files changed, 31 insertions, 42 deletions

diff --git a/arch/arm/plat-omap/dmtimer.c b/arch/arm/plat-omap/dmtimer.c
index 9deeb3064d33..4c28452ba078 100644
--- a/arch/arm/plat-omap/dmtimer.c
+++ b/arch/arm/plat-omap/dmtimer.c
@@ -99,32 +99,39 @@ static void omap_timer_restore_context(struct omap_dm_timer *timer)
                                 timer->context.tclr);
 }
 
-static void omap_dm_timer_wait_for_reset(struct omap_dm_timer *timer)
+static int omap_dm_timer_reset(struct omap_dm_timer *timer)
 {
-        int c;
+        u32 l, timeout = 100000;
 
-        if (!timer->sys_stat)
-                return;
+        if (timer->revision != 1)
+                return -EINVAL;
 
-        c = 0;
-        while (!(__raw_readl(timer->sys_stat) & 1)) {
-                c++;
-                if (c > 100000) {
-                        printk(KERN_ERR "Timer failed to reset\n");
-                        return;
-                }
+        omap_dm_timer_write_reg(timer, OMAP_TIMER_IF_CTRL_REG, 0x06);
+
+        do {
+                l = __omap_dm_timer_read(timer,
+                                         OMAP_TIMER_V1_SYS_STAT_OFFSET, 0);
+        } while (!l && timeout--);
+
+        if (!timeout) {
+                dev_err(&timer->pdev->dev, "Timer failed to reset\n");
+                return -ETIMEDOUT;
         }
-}
 
-static void omap_dm_timer_reset(struct omap_dm_timer *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);
+        /* Configure timer for smart-idle mode */
+        l = __omap_dm_timer_read(timer, OMAP_TIMER_OCP_CFG_OFFSET, 0);
+        l |= 0x2 << 0x3;
+        __omap_dm_timer_write(timer, OMAP_TIMER_OCP_CFG_OFFSET, l, 0);
+
+        timer->posted = 0;
+
+        return 0;
 }
 
 int omap_dm_timer_prepare(struct omap_dm_timer *timer)
 {
+        int rc;
+
         /*
          * FIXME: OMAP1 devices do not use the clock framework for dmtimers so
          * do not call clk_get() for these devices.
@@ -140,8 +147,13 @@ 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);
+        if (timer->capability & OMAP_TIMER_NEEDS_RESET) {
+                rc = omap_dm_timer_reset(timer);
+                if (rc) {
+                        omap_dm_timer_disable(timer);
+                        return rc;
+                }
+        }
 
         __omap_dm_timer_enable_posted(timer);
         omap_dm_timer_disable(timer);
diff --git a/arch/arm/plat-omap/include/plat/dmtimer.h b/arch/arm/plat-omap/include/plat/dmtimer.h
index 05a36e16f3f4..c5c890dabca4 100644
--- a/arch/arm/plat-omap/include/plat/dmtimer.h
+++ b/arch/arm/plat-omap/include/plat/dmtimer.h
@@ -267,7 +267,6 @@ struct omap_dm_timer {
         struct clk *fclk;
 
         void __iomem    *io_base;
-        void __iomem    *sys_stat;      /* TISTAT timer status */
         void __iomem    *irq_stat;      /* TISR/IRQSTATUS interrupt status */
         void __iomem    *irq_ena;       /* irq enable */
         void __iomem    *irq_dis;       /* irq disable, only on v2 ip */
@@ -317,8 +316,6 @@ static inline void __omap_dm_timer_init_regs(struct omap_dm_timer *timer)
         tidr = __raw_readl(timer->io_base);
         if (!(tidr >> 16)) {
                 timer->revision = 1;
-                timer->sys_stat = timer->io_base +
-                                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 = timer->io_base + OMAP_TIMER_V1_INT_EN_OFFSET;
@@ -326,7 +323,6 @@ static inline void __omap_dm_timer_init_regs(struct omap_dm_timer *timer)
                 timer->func_base = timer->io_base;
         } else {
                 timer->revision = 2;
-                timer->sys_stat = NULL;
                 timer->irq_stat = timer->io_base + OMAP_TIMER_V2_IRQSTATUS;
                 timer->irq_ena = timer->io_base + OMAP_TIMER_V2_IRQENABLE_SET;
                 timer->irq_dis = timer->io_base + OMAP_TIMER_V2_IRQENABLE_CLR;
@@ -337,25 +333,6 @@ static inline void __omap_dm_timer_init_regs(struct omap_dm_timer *timer)
         }
 }
 
-/* Assumes the source clock has been set by caller */
-static inline void __omap_dm_timer_reset(struct omap_dm_timer *timer,
-                                        int autoidle, int wakeup)
-{
-        u32 l;
-
-        l = __raw_readl(timer->io_base + OMAP_TIMER_OCP_CFG_OFFSET);
-        l |= 0x02 << 3;  /* Set to smart-idle mode */
-        l |= 0x2 << 8;   /* Set clock activity to perserve f-clock on idle */
-
-        if (autoidle)
-                l |= 0x1 << 0;
-
-        if (wakeup)
-                l |= 1 << 2;
-
-        __raw_writel(l, timer->io_base + OMAP_TIMER_OCP_CFG_OFFSET);
-}
-
 /*
  * __omap_dm_timer_enable_posted - enables write posted mode
  * @timer:      pointer to timer instance handle