* Patch by Steven Scholz, 18 Oct 2003:
Fix AT91RM9200 ethernet driver
* Patch by Nye Liu, 17 Oct 2003:
Fix typo in include/mpc8xx.h
* Patch by Richard Woodruff, 16 Oct 03:
Fixes for cpu/arm925/interrupt.c
- Initialize timestamp & lastdec vars.
- fix timestamp overflows.
- fix lastdec overflow.
- smarter normalization to allow udelay() below 1ms to work.
* Patch by Scott McNutt, 16 Oct
add networking support for the Altera Nios Development Kit,
Cyclone Edition (DK-1C20)
* Patch by Jon Diekema, 14 Oct 2003:
add hint about doc/README.silent to README file
diff --git a/cpu/arm925t/interrupts.c b/cpu/arm925t/interrupts.c
index 132af1a..7897184 100644
--- a/cpu/arm925t/interrupts.c
+++ b/cpu/arm925t/interrupts.c
@@ -185,9 +185,14 @@
{
int32_t val;
+ /* Start the decrementer ticking down from 0xffffffff */
*((int32_t *) (CFG_TIMERBASE + LOAD_TIM)) = TIMER_LOAD_VAL;
val = MPUTIM_ST | MPUTIM_AR | MPUTIM_CLOCK_ENABLE | (CFG_PVT << MPUTIM_PTV_BIT);
*((int32_t *) (CFG_TIMERBASE + CNTL_TIMER)) = val;
+
+ /* init the timestamp and lastdec value */
+ reset_timer_masked();
+
return (0);
}
@@ -210,7 +215,7 @@
timestamp = t;
}
-/* very rough timer... */
+/* delay x useconds AND perserve advance timstamp value */
void udelay (unsigned long usec)
{
#ifdef CONFIG_INNOVATOROMAP1510
@@ -220,16 +225,24 @@
for (i = time_remaining; i > 0; i--) {
}
#else
+ ulong tmo, tmp;
- ulong tmo;
+ 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 */
+ tmo = usec * CFG_HZ;
+ tmo /= (1000*1000);
+ }
- tmo = usec / 1000;
- tmo *= CFG_HZ;
- tmo /= 1000;
+ tmp = get_timer (0); /* get current timestamp */
+ if( (tmo + tmp) < tmp ) /* if setting this fordward will roll time stamp */
+ reset_timer_masked (); /* reset "advancing" timestamp to 0, set lastdec value */
+ else
+ tmo += tmp; /* else, set advancing stamp wake up time */
- tmo += get_timer (0);
-
- while (get_timer_masked () < tmo)
+ while (get_timer_masked () < tmo)/* loop till event */
/*NOP*/;
#endif
}
@@ -237,19 +250,23 @@
void reset_timer_masked (void)
{
/* reset time */
- lastdec = READ_TIMER;
- timestamp = 0;
+ lastdec = READ_TIMER; /* capure current decrementer value time */
+ timestamp = 0; /* start "advancing" time stamp from 0 */
}
ulong get_timer_masked (void)
{
- ulong now = READ_TIMER; /* current tick value */
+ ulong now = READ_TIMER; /* current tick value */
- if (lastdec >= now) { /* did I roll (rem decrementer) */
+ if (lastdec >= now) { /* normal mode (non roll) */
/* normal mode */
- timestamp += lastdec - now; /* record amount of time since last check */
- } else {
- /* we have an overflow ... */
+ timestamp += lastdec - now; /* move stamp fordward with absoulte diff ticks */
+ } else { /* we have overflow of the count down timer */
+ /* nts = ts + ld + (TLV - now)
+ * ts=old stamp, ld=time that passed before passing through -1
+ * (TLV-now) amount of time after passing though -1
+ * nts = new "advancing time stamp"...it could also roll and cause problems.
+ */
timestamp += lastdec + TIMER_LOAD_VAL - now;
}
lastdec = now;
@@ -257,6 +274,7 @@
return timestamp;
}
+/* waits specified delay value and resets timestamp */
void udelay_masked (unsigned long usec)
{
#ifdef CONFIG_INNOVATOROMAP1510
@@ -265,15 +283,20 @@
for (i=time_remaining; i>0; i--) { }
#else
- ulong tmo;
+ ulong tmo, tmp;
- tmo = usec / 1000;
- tmo *= CFG_HZ;
- tmo /= 1000;
+ 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 */
+ tmo = usec * CFG_HZ;
+ tmo /= (1000*1000);
+ }
- reset_timer_masked ();
+ reset_timer_masked (); /* set "advancing" timestamp to 0, set lastdec vaule */
- while (get_timer_masked () < tmo)
+ while (get_timer_masked () < tmo) /* wait for time stamp to overtake tick number.*/
/*NOP*/;
#endif
}
@@ -292,7 +315,7 @@
* On ARM it returns the number of timer ticks per second.
*/
ulong get_tbclk (void)
-{ /* poor timer, may need to improve especiall for bootp. */
+{
ulong tbclk;
tbclk = CFG_HZ;