MX5/MX6: add missing get_ticks() and get_tbclk()

commit f31a911fe (arm, post: add missing post_time_ms for arm)
enables get_ticks and get_tbclk for all arm based boards,
MX5/MX6 have not yet implemented.

Signed-off-by: Stefano Babic <sbabic@denx.de>
CC: Dirk Behme <dirk.behme@de.bosch.com>
CC: Jason Liu <jason.hui@linaro.org>
CC: Marek Vasut <marek.vasut@gmail.com>

diff --git a/arch/arm/cpu/armv7/imx-common/timer.c b/arch/arm/cpu/armv7/imx-common/timer.c
index 98e9f4ad61f978be533bce1ec996e3909028da75..1645ff83f47be8548e4bf713222e3766d7a42e99 100755 (executable)
--- a/arch/arm/cpu/armv7/imx-common/timer.c
+++ b/arch/arm/cpu/armv7/imx-common/timer.c
@@ -25,6 +25,7 @@
 
 #include <common.h>
 #include <asm/io.h>
+#include <div64.h>
 #include <asm/arch/imx-regs.h>
 
 /* General purpose timers registers */
@@ -50,6 +51,22 @@ DECLARE_GLOBAL_DATA_PTR;
 #define timestamp (gd->tbl)
 #define lastinc (gd->lastinc)
 
+static inline unsigned long long tick_to_time(unsigned long long tick)
+{
+       tick *= CONFIG_SYS_HZ;
+       do_div(tick, CLK_32KHZ);
+
+       return tick;
+}
+
+static inline unsigned long long us_to_tick(unsigned long long usec)
+{
+       usec *= CLK_32KHZ;
+       do_div(usec, 1000000);
+
+       return usec;
+}
+
 int timer_init(void)
 {
        int i;
@@ -75,36 +92,58 @@ int timer_init(void)
        return 0;
 }
 
-ulong get_timer_masked(void)
+unsigned long long get_ticks(void)
 {
-       ulong val = __raw_readl(&cur_gpt->counter);
-       val /= (CLK_32KHZ / CONFIG_SYS_HZ);
-       if (val >= lastinc)
-               timestamp += (val - lastinc);
-       else
-               timestamp += ((0xFFFFFFFF / (CLK_32KHZ / CONFIG_SYS_HZ))
-                               - lastinc) + val;
-       lastinc = val;
+       ulong now = __raw_readl(&cur_gpt->counter); /* current tick value */
+
+       if (now >= lastinc) {
+               /*
+                * normal mode (non roll)
+                * move stamp forward with absolut diff ticks
+                */
+               timestamp += (now - lastinc);
+       } else {
+               /* we have rollover of incrementer */
+               timestamp += (0xFFFFFFFF - lastinc) + now;
+       }
+       lastinc = now;
        return timestamp;
 }
 
+ulong get_timer_masked(void)
+{
+       /*
+        * get_ticks() returns a long long (64 bit), it wraps in
+        * 2^64 / CONFIG_MX25_CLK32 = 2^64 / 2^15 = 2^49 ~ 5 * 10^14 (s) ~
+        * 5 * 10^9 days... and get_ticks() * CONFIG_SYS_HZ wraps in
+        * 5 * 10^6 days - long enough.
+        */
+       return tick_to_time(get_ticks());
+}
+
 ulong get_timer(ulong base)
 {
        return get_timer_masked() - base;
 }
 
-/* delay x useconds AND preserve advance timestamp value */
+/* delay x useconds AND preserve advance timstamp value */
 void __udelay(unsigned long usec)
 {
-       unsigned long now, start, tmo;
-       tmo = usec * (CLK_32KHZ / 1000) / 1000;
-
-       if (!tmo)
-               tmo = 1;
+       unsigned long long tmp;
+       ulong tmo;
 
-       now = start = readl(&cur_gpt->counter);
+       tmo = us_to_tick(usec);
+       tmp = get_ticks() + tmo;        /* get current timestamp */
 
-       while ((now - start) < tmo)
-               now = readl(&cur_gpt->counter);
+       while (get_ticks() < tmp)       /* loop till event */
+                /*NOP*/;
+}
 
+/*
+ * This function is derived from PowerPC code (timebase clock frequency).
+ * On ARM it returns the number of timer ticks per second.
+ */
+ulong get_tbclk(void)
+{
+       return CLK_32KHZ;
 }