patch-2.4.19 linux-2.4.19/include/asm-cris/timex.h

• Lines: 46
• Date: Fri Aug 2 17:39:45 2002
• Orig file: linux-2.4.18/include/asm-cris/timex.h
• Orig date: Fri Nov 9 14:11:15 2001

diff -urN linux-2.4.18/include/asm-cris/timex.h linux-2.4.19/include/asm-cris/timex.h
@@ -2,25 +2,34 @@
  * linux/include/asm-cris/timex.h
  *
  * CRIS architecture timex specifications
+ * 2002-03-04    Johan Adolfsson
+ *      Use prescale timer at 25000 Hz instead of the baudrate timer at 
+ *      19200 to get rid of the 64ppm to fast timer (and we get better 
+ *      resolution within a jiffie as well.
  */
 #ifndef _ASM_CRIS_TIMEX_H
 #define _ASM_CRIS_TIMEX_H
 
-#define CLOCK_TICK_RATE 19200 /* Underlying frequency of the HZ timer */
-
-/* The timer0 values gives ~52.1us resolution (1/19200) but interrupts at HZ*/
+/* The prescaler clock runs at 25MHz, we divide it by 1000 in the prescaler */
+/* If you change anything here you must check time.c as well... */
+#define PRESCALE_FREQ 25000000
+#define PRESCALE_VALUE 1000
+#define CLOCK_TICK_RATE 25000 /* Underlying frequency of the HZ timer */
+/* The timer0 values gives 40us resolution (1/25000) but interrupts at HZ*/
 #define TIMER0_FREQ (CLOCK_TICK_RATE)
-#define TIMER0_CLKSEL c19k2Hz
+#define TIMER0_CLKSEL flexible
 #define TIMER0_DIV (TIMER0_FREQ/(HZ))
-/* This is the slow one: */
-/*
+
+
 #define GET_JIFFIES_USEC() \
-  ( (*R_TIMER0_DATA - TIMER0_DIV) * (1000000/HZ)/TIMER0_DIV )
-*/
-/* This is the fast version: */
-extern unsigned short cris_timer0_value_us[TIMER0_DIV+1]; /* in kernel/time.c */
-#define GET_JIFFIES_USEC() (cris_timer0_value_us[*R_TIMER0_DATA])
+  ( (TIMER0_DIV - *R_TIMER0_DATA) * (1000000/HZ)/TIMER0_DIV )
+
+unsigned long get_ns_in_jiffie(void);
 
+static inline unsigned long get_us_in_jiffie_highres(void)
+{
+	return get_ns_in_jiffie()/1000;
+}
 /*
  * We don't have a cycle-counter.. but we do not support SMP anyway where this is
  * used so it does not matter.