upgrade to upstream version 2013.07

[karo-tx-uboot.git] / arch / arm / imx-common / timer.c

diff --git a/arch/arm/imx-common/timer.c b/arch/arm/imx-common/timer.c
index ab37d641ece97c82f230ad9e6a89511fea8fddff..92712a6de55b86a2432bbbf02ac694566b2c3b68 100644 (file)
--- a/arch/arm/imx-common/timer.c
+++ b/arch/arm/imx-common/timer.c
@@ -4,23 +4,7 @@
  *
  * (C) Copyright 2009 Freescale Semiconductor, Inc.
  *
- * See file CREDITS for list of people who contributed to this
- * project.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License as
- * published by the Free Software Foundation; either version 2 of
- * the License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
- * MA 02111-1307 USA
+ * SPDX-License-Identifier:    GPL-2.0+
  */
 
 #include <common.h>
@@ -48,17 +32,22 @@ static struct mxc_gpt *cur_gpt = (struct mxc_gpt *)GPT1_BASE_ADDR;
 
 DECLARE_GLOBAL_DATA_PTR;
 
-#define timestamp (gd->arch.tbl)
-#define lastinc (gd->arch.lastinc)
-
 static inline unsigned long long tick_to_time(unsigned long long tick)
 {
        tick *= CONFIG_SYS_HZ;
        do_div(tick, MXC_CLK32);
-
        return tick;
 }
 
+static inline unsigned long time_to_tick(unsigned long time)
+{
+       unsigned long long ticks = (unsigned long long)time;
+
+       ticks *= MXC_CLK32;
+       do_div(ticks, CONFIG_SYS_HZ);
+       return ticks;
+}
+
 static inline unsigned long long us_to_tick(unsigned long long usec)
 {
        usec = usec * MXC_CLK32 + 999999;
@@ -70,7 +59,6 @@ static inline unsigned long long us_to_tick(unsigned long long usec)
 int timer_init(void)
 {
        int i;
-       ulong val;
 
        /* setup GP Timer 1 */
        __raw_writel(GPTCR_SWR, &cur_gpt->control);
@@ -85,10 +73,10 @@ int timer_init(void)
        i = __raw_readl(&cur_gpt->control);
        __raw_writel(i | GPTCR_CLKSOURCE_32 | GPTCR_TEN, &cur_gpt->control);
 
-       val = __raw_readl(&cur_gpt->counter);
-       lastinc = val / (MXC_CLK32 / CONFIG_SYS_HZ);
-       timestamp = 0;
+       gd->arch.tbl = __raw_readl(&cur_gpt->counter);
+       gd->arch.tbu = 0;
 
+       gd->arch.timer_rate_hz = MXC_CLK32;
        return 0;
 }
 
@@ -96,18 +84,11 @@ unsigned long long get_ticks(void)
 {
        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;
+       /* increment tbu if tbl has rolled over */
+       if (now < gd->arch.tbl)
+               gd->arch.tbu++;
+       gd->arch.tbl = now;
+       return (((unsigned long long)gd->arch.tbu) << 32) | gd->arch.tbl;
 }
 
 ulong get_timer_masked(void)
@@ -118,25 +99,36 @@ ulong get_timer_masked(void)
         * 5 * 10^9 days... and get_ticks() * CONFIG_SYS_HZ wraps in
         * 5 * 10^6 days - long enough.
         */
+       /*
+        * LW: get_ticks() returns a long long with the top 32 bits always ZERO!
+        * Thus the calculation above is not true.
+        * A 64bit timer value would only make sense if it was
+        * consistently used throughout the code. Thus also the parameter
+        * to get_timer() and its return value would need to be 64bit wide!
+        */
        return tick_to_time(get_ticks());
 }
 
 ulong get_timer(ulong base)
 {
-       return get_timer_masked() - base;
+       return tick_to_time(get_ticks() - time_to_tick(base));
 }
 
 /* delay x useconds AND preserve advance timstamp value */
 void __udelay(unsigned long usec)
 {
-       unsigned long long tmp;
-       ulong tmo;
+       unsigned long start = __raw_readl(&cur_gpt->counter);
+       unsigned long ticks;
+
+       if (usec == 0)
+               return;
 
-       tmo = us_to_tick(usec);
-       tmp = get_ticks() + tmo;        /* get current timestamp */
+       ticks = us_to_tick(usec);
+       if (ticks == 0)
+               ticks++;
 
-       while (get_ticks() < tmp)       /* loop till event */
-                /*NOP*/;
+       while (__raw_readl(&cur_gpt->counter) - start < ticks)
+               /* loop till event */;
 }
 
 /*
@@ -145,5 +137,5 @@ void __udelay(unsigned long usec)
  */
 ulong get_tbclk(void)
 {
-       return MXC_CLK32;
+       return gd->arch.timer_rate_hz;
 }