Update the i.MX31 Kernel to 2.6.232.6.23-mx31ads-2008022618072.6.23-mx31-200802261807

This is the result of a brute-force attempt to update the kernel to 2.6.23.
Now that we have a git tree, our effort will be a little nicer in the future.

Signed-off-by: Justin Waters <justin.waters@timesys.com>

1 files changed, 31 insertions, 3 deletions

diff --git a/include/asm-i386/timer.h b/include/asm-i386/timer.h
index 153770e25faa..0db7e994fb8b 100644
--- a/include/asm-i386/timer.h
+++ b/include/asm-i386/timer.h
@@ -5,18 +5,46 @@
 
 #define TICK_SIZE (tick_nsec / 1000)
 
-void setup_pit_timer(void);
 unsigned long long native_sched_clock(void);
 unsigned long native_calculate_cpu_khz(void);
 
 extern int timer_ack;
 extern int no_timer_check;
-extern int no_sync_cmos_clock;
 extern int recalibrate_cpu_khz(void);
 
 #ifndef CONFIG_PARAVIRT
-#define get_scheduled_cycles(val) rdtscll(val)
 #define calculate_cpu_khz() native_calculate_cpu_khz()
 #endif
 
+/* Accellerators for sched_clock()
+ * convert from cycles(64bits) => nanoseconds (64bits)
+ *  basic equation:
+ *		ns = cycles / (freq / ns_per_sec)
+ *		ns = cycles * (ns_per_sec / freq)
+ *		ns = cycles * (10^9 / (cpu_khz * 10^3))
+ *		ns = cycles * (10^6 / cpu_khz)
+ *
+ *	Then we use scaling math (suggested by george@mvista.com) to get:
+ *		ns = cycles * (10^6 * SC / cpu_khz) / SC
+ *		ns = cycles * cyc2ns_scale / SC
+ *
+ *	And since SC is a constant power of two, we can convert the div
+ *  into a shift.
+ *
+ *  We can use khz divisor instead of mhz to keep a better percision, since
+ *  cyc2ns_scale is limited to 10^6 * 2^10, which fits in 32 bits.
+ *  (mathieu.desnoyers@polymtl.ca)
+ *
+ *			-johnstul@us.ibm.com "math is hard, lets go shopping!"
+ */
+extern unsigned long cyc2ns_scale __read_mostly;
+
+#define CYC2NS_SCALE_FACTOR 10 /* 2^10, carefully chosen */
+
+static inline unsigned long long cycles_2_ns(unsigned long long cyc)
+{
+	return (cyc * cyc2ns_scale) >> CYC2NS_SCALE_FACTOR;
+}
+
+
 #endif