svn commit: r192364 - projects/mips/sys/mips/mips

[Oleksandr Tymoshenko]

Author: gonzo
Date: Tue May 19 02:43:21 2009
New Revision: 192364
URL: http://svn.freebsd.org/changeset/base/192364

Log:
  - Cleanup ticker initialization code. For some MIPS cpu Counter
      register increments only every second cycle. The only timing
      references for us is Count value. Therefore it's better to convert
      frequencies related to it and use them. Besides cleanup this commit
      fixes twice more then requested sleep interval problem.

Modified:
  projects/mips/sys/mips/mips/tick.c

Modified: projects/mips/sys/mips/mips/tick.c
==============================================================================
--- projects/mips/sys/mips/mips/tick.c	Tue May 19 01:58:00 2009	(r192363)
+++ projects/mips/sys/mips/mips/tick.c	Tue May 19 02:43:21 2009	(r192364)
@@ -138,25 +138,19 @@ mips_timer_init_params(uint64_t platform
 	 * function should  be called before cninit.
 	 */
 	counter_freq = platform_counter_freq;
+	/*
+	 * XXX: Some MIPS32 cores update the Count register only every two
+	 * pipeline cycles.
+	 */
+	if (double_count != 0)
+		counter_freq /= 2;
+
 	cycles_per_tick = counter_freq / 1000;
-	if (double_count)
-		cycles_per_tick *= 2;
 	cycles_per_hz = counter_freq / hz;
 	cycles_per_usec = counter_freq / (1 * 1000 * 1000);
 	cycles_per_sec =  counter_freq ;
 	
 	counter_timecounter.tc_frequency = counter_freq;
-	/*
-	 * XXX: Some MIPS32 cores update the Count register only every two
-	 * pipeline cycles.
-	 * XXX2: We can read this from the hardware register on some
-	 * systems.  Need to investigate.
-	 */
-	if (double_count != 0) {
-		cycles_per_hz /= 2;
-		cycles_per_usec /= 2;
-		cycles_per_sec /= 2;
-	}
 	printf("hz=%d cyl_per_hz:%jd cyl_per_usec:%jd freq:%jd cyl_per_hz:%jd cyl_per_sec:%jd\n",
 	       hz,
 	       cycles_per_tick,
@@ -346,6 +340,7 @@ clock_attach(device_t dev)
 		device_printf(dev, "bus_setup_intr returned %d\n", error);
 		return (error);
 	}
+
 	mips_wr_compare(mips_rd_count() + counter_freq / hz);
 	return (0);
 }