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

reset timers so it's save to use udelay() in timeout code.
This commit is contained in:
wdenk
2005-04-04 12:08:28 +00:00
parent 50712ba16e
commit 101e8dfa2a
14 changed files with 140 additions and 80 deletions

View File

@@ -26,7 +26,7 @@
*
* 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
* 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
@@ -116,15 +116,15 @@ void show_regs (struct pt_regs *regs)
flags = condition_codes (regs);
printf ("pc : [<%08lx>] lr : [<%08lx>]\n"
"sp : %08lx ip : %08lx fp : %08lx\n",
printf ("pc : [<%08lx>] lr : [<%08lx>]\n"
"sp : %08lx ip : %08lx fp : %08lx\n",
instruction_pointer (regs),
regs->ARM_lr, regs->ARM_sp, regs->ARM_ip, regs->ARM_fp);
printf ("r10: %08lx r9 : %08lx r8 : %08lx\n",
printf ("r10: %08lx r9 : %08lx r8 : %08lx\n",
regs->ARM_r10, regs->ARM_r9, regs->ARM_r8);
printf ("r7 : %08lx r6 : %08lx r5 : %08lx r4 : %08lx\n",
printf ("r7 : %08lx r6 : %08lx r5 : %08lx r4 : %08lx\n",
regs->ARM_r7, regs->ARM_r6, regs->ARM_r5, regs->ARM_r4);
printf ("r3 : %08lx r2 : %08lx r1 : %08lx r0 : %08lx\n",
printf ("r3 : %08lx r2 : %08lx r1 : %08lx r0 : %08lx\n",
regs->ARM_r3, regs->ARM_r2, regs->ARM_r1, regs->ARM_r0);
printf ("Flags: %c%c%c%c",
flags & CC_N_BIT ? 'N' : 'n',
@@ -242,17 +242,17 @@ void udelay (unsigned long usec)
{
ulong tmo, tmp;
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 */
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);
}
tmp = get_timer (0); /* get current timestamp */
if( (tmo + tmp + 1) < tmp ) /* if setting this fordward will roll time stamp */
if( (tmo + tmp + 1) < 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 */
@@ -265,7 +265,7 @@ void reset_timer_masked (void)
{
/* reset time */
lastdec = READ_TIMER; /* capure current decrementer value time */
timestamp = 0; /* start "advancing" time stamp from 0 */
timestamp = 0; /* start "advancing" time stamp from 0 */
}
ulong get_timer_masked (void)
@@ -292,20 +292,24 @@ ulong get_timer_masked (void)
void udelay_masked (unsigned long usec)
{
ulong tmo;
ulong endtime;
signed long diff;
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 */
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 (); /* 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);
}
/*