Fix timer code for ARM systems: make sure that udelay() does not

[u-boot] / cpu / arm925t / interrupts.c

diff --git a/cpu/arm925t/interrupts.c b/cpu/arm925t/interrupts.c
index d77c4e6f6778f6640ef0e411c8c4bd0d14f7de35..57bb4eab6f648b711d4939da2e9dd9014b26c7c5 100644 (file)
--- a/cpu/arm925t/interrupts.c
+++ b/cpu/arm925t/interrupts.c
@@ -38,7 +38,6 @@
 
 #include <asm/proc-armv/ptrace.h>
 
-extern void reset_cpu(ulong addr);
 #define TIMER_LOAD_VAL 0xffffffff
 
 /* macro to read the 32 bit timer */
@@ -215,16 +214,9 @@ void set_timer (ulong t)
        timestamp = t;
 }
 
-/* delay x useconds AND perserve advance timstamp value */
+/* delay x useconds AND preserve advance timestamp value */
 void udelay (unsigned long usec)
 {
-#ifdef CONFIG_INNOVATOROMAP1510
-#define LOOPS_PER_MSEC 60              /* tuned on omap1510 */
-       volatile int i, time_remaining = LOOPS_PER_MSEC * usec;
-
-       for (i = time_remaining; i > 0; i--) {
-       }
-#else
        ulong tmo, tmp;
 
        if(usec >= 1000){               /* if "big" number, spread normalization to seconds */
@@ -242,9 +234,8 @@ void udelay (unsigned long usec)
        else
                tmo += tmp;             /* else, set advancing stamp wake up time */
 
-       while (get_timer_masked () < tmo)/* loop till event */
+       while (get_timer_masked () < tmo) /* loop till event */
                /*NOP*/;
-#endif
 }
 
 void reset_timer_masked (void)
@@ -284,20 +275,24 @@ void udelay_masked (unsigned long usec)
 #else
 
        ulong tmo;
+       ulong endtime;
+       signed long diff;
 
-       if(usec >= 1000){               /* if "big" number, spread normalization to seconds */
+       if (usec >= 1000) {             /* if "big" number, spread normalization to seconds */
                tmo = usec / 1000;      /* start to normalize for usec to ticks per sec */
                tmo *= CFG_HZ;          /* find number of "ticks" to wait to achieve target */
                tmo /= 1000;            /* finish normalize. */
-       }else{                          /* else small number, don't kill it prior to HZ multiply */
+       } else {                        /* else small number, don't kill it prior to HZ multiply */
                tmo = usec * CFG_HZ;
                tmo /= (1000*1000);
        }
 
-       reset_timer_masked ();  /* set "advancing" timestamp to 0, set lastdec vaule */
+       endtime = get_timer_masked () + tmo;
 
-       while (get_timer_masked () < tmo) /* wait for time stamp to overtake tick number.*/
-               /*NOP*/;
+       do {
+               ulong now = get_timer_masked ();
+               diff = endtime - now;
+       } while (diff >= 0);
 #endif
 }