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

[platform/kernel/u-boot.git] / cpu / arm926ejs / interrupts.c

diff --git a/cpu/arm926ejs/interrupts.c b/cpu/arm926ejs/interrupts.c
index 062515e..ae8082d 100644 (file)
--- a/cpu/arm926ejs/interrupts.c
+++ b/cpu/arm926ejs/interrupts.c
@@ -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;
-
-       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 */
+       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 */
                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);
 }
 
 /*