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authorJoel Sherrill <joel.sherrill@OARcorp.com>2006-10-23 19:38:12 +0000
committerJoel Sherrill <joel.sherrill@OARcorp.com>2006-10-23 19:38:12 +0000
commit8d41236f6d4bdb59545f2052bff5de122ffebb72 (patch)
tree6e480d466b16bf1491e5cb6954d921a4d6f7936f /c/src/lib/libbsp/bfin/shared/timer/timer.c
parent2006-10-23 Joel Sherrill <joel@OARcorp.com> (diff)
downloadrtems-8d41236f6d4bdb59545f2052bff5de122ffebb72.tar.bz2
2006-10-23 Joel Sherrill <joel@OARcorp.com>
* bfin/ChangeLog, bfin/Makefile.am, bfin/acinclude.m4, bfin/configure.ac, bfin/eZKit533/.cvsignore, bfin/eZKit533/ChangeLog, bfin/eZKit533/Makefile.am, bfin/eZKit533/README, bfin/eZKit533/bsp_specs, bfin/eZKit533/configure, bfin/eZKit533/configure.ac, bfin/eZKit533/preinstall.am, bfin/eZKit533/times, bfin/eZKit533/console/console-io.c, bfin/eZKit533/include/.cvsignore, bfin/eZKit533/include/bsp.h, bfin/eZKit533/include/bspopts.h.in, bfin/eZKit533/include/coverhd.h, bfin/eZKit533/include/tm27.h, bfin/eZKit533/startup/bspstart.c, bfin/eZKit533/startup/linkcmds, bfin/shared/clock/clockdrv.c, bfin/shared/clock/rtc.c, bfin/shared/clock/tod.h, bfin/shared/console/console.c, bfin/shared/start/start.S, bfin/shared/timer/timer.c: New files.
Diffstat (limited to '')
-rw-r--r--c/src/lib/libbsp/bfin/shared/timer/timer.c106
1 files changed, 106 insertions, 0 deletions
diff --git a/c/src/lib/libbsp/bfin/shared/timer/timer.c b/c/src/lib/libbsp/bfin/shared/timer/timer.c
new file mode 100644
index 0000000000..9bbf6f7a83
--- /dev/null
+++ b/c/src/lib/libbsp/bfin/shared/timer/timer.c
@@ -0,0 +1,106 @@
+/* bspstart.c for eZKit533
+ *
+ * This file manages the benchmark timer used by the RTEMS Timing Test
+ * Suite. Each measured time period is demarcated by calls to
+ * Timer_initialize() and Read_timer(). Read_timer() usually returns
+ * the number of microseconds since Timer_initialize() exitted.
+ *
+ * Copyright (c) 2006 by Atos Automacao Industrial Ltda.
+ * written by Alain Schaefer <alain.schaefer@easc.ch>
+ * and Antonio Giovanini <antonio@atos.com.br>
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rtems.com/license/LICENSE.
+ *
+ * $Id$
+ */
+
+
+#include <rtems.h>
+#include <bsp.h>
+
+
+uint32_t Timer_interrupts;
+rtems_boolean Timer_driver_Find_average_overhead;
+
+/*
+ * Timer_initialize
+ *
+ * Blackfin processor has a counter for clock cycles.
+ */
+void Timer_initialize( void )
+{
+
+ /*reset counters*/
+ asm ("R2 = 0;");
+ asm ("CYCLES = R2;");
+ asm ("CYCLES2 = R2;");
+ /*start counters*/
+ asm ("R2 = SYSCFG;");
+ asm ("BITSET(R2,1);");
+ asm ("SYSCFG = R2");
+
+}
+
+/*
+ * The following controls the behavior of Read_timer().
+ *
+ * AVG_OVEREHAD is the overhead for starting and stopping the timer. It
+ * is usually deducted from the number returned.
+ *
+ * LEAST_VALID is the lowest number this routine should trust. Numbers
+ * below this are "noise" and zero is returned.
+ */
+
+#define AVG_OVERHEAD 0 /* It typically takes X.X microseconds */
+ /* (Y countdowns) to start/stop the timer. */
+ /* This value is in microseconds. */
+#define LEAST_VALID 1 /* Don't trust a clicks value lower than this */
+
+int Read_timer( void )
+{
+ uint32_t clicks;
+ uint32_t total;
+ register int *cycles asm ("R2");
+
+ /* stop counter */
+ asm("R2 = SYSCFG;");
+ asm("BITCLR(R2,1);");
+ asm("SYSCFG = R2;");
+ asm("R2 = CYCLES;");
+
+
+ clicks = cycles; /* Clock cycles */
+
+ /* converting to microseconds */
+ total = clicks / (CCLK/1000000);
+
+ if ( Timer_driver_Find_average_overhead == 1 )
+ return total; /* in XXX microsecond units */
+ else {
+ if ( total < LEAST_VALID )
+ return 0; /* below timer resolution */
+ /*
+ * Somehow convert total into microseconds
+ */
+ return (total - AVG_OVERHEAD);
+ }
+}
+
+/*
+ * Empty function call used in loops to measure basic cost of looping
+ * in Timing Test Suite.
+ */
+
+rtems_status_code Empty_function( void )
+{
+ return RTEMS_SUCCESSFUL;
+}
+
+void Set_find_average_overhead(
+ rtems_boolean find_flag
+)
+{
+ Timer_driver_Find_average_overhead = find_flag;
+}