vserver 1.9.3

[linux-2.6.git] / drivers / char / ftape / lowlevel / ftape-calibr.c

diff --git a/drivers/char/ftape/lowlevel/ftape-calibr.c b/drivers/char/ftape/lowlevel/ftape-calibr.c
index 34f0e69..956b258 100644 (file)
--- a/drivers/char/ftape/lowlevel/ftape-calibr.c
+++ b/drivers/char/ftape/lowlevel/ftape-calibr.c
@@ -31,7 +31,10 @@
 #include <asm/io.h>
 #if defined(__alpha__)
 # include <asm/hwrpb.h>
-#elif defined(__i386__) || defined(__x86_64__)
+#elif defined(__x86_64__)
+# include <asm/msr.h>
+# include <asm/timex.h>
+#elif defined(__i386__)
 # include <linux/timex.h>
 #endif
 #include <linux/ftape.h>
@@ -45,7 +48,7 @@
 # error Ftape is not implemented for this architecture!
 #endif
 
-#if defined(__alpha__)
+#if defined(__alpha__) || defined(__x86_64__)
 static unsigned long ps_per_cycle = 0;
 #endif
 
@@ -72,7 +75,18 @@ unsigned int ftape_timestamp(void)
 
        asm volatile ("rpcc %0" : "=r" (r));
        return r;
-#elif defined(__i386__) || defined(__x86_64__)
+#elif defined(__x86_64__)
+       unsigned long r;
+       rdtscl(r);
+       return r;
+#elif defined(__i386__)
+
+/*
+ * Note that there is some time between counter underflowing and jiffies
+ * increasing, so the code below won't always give correct output.
+ * -Vojtech
+ */
+
        unsigned long flags;
        __u16 lo;
        __u16 hi;
@@ -89,9 +103,9 @@ unsigned int ftape_timestamp(void)
 
 static unsigned int short_ftape_timestamp(void)
 {
-#if defined(__alpha__)
+#if defined(__alpha__) || defined(__x86_64__)
        return ftape_timestamp();
-#elif defined(__i386__) || defined(__x86_64__)
+#elif defined(__i386__)
        unsigned int count;
        unsigned long flags;
  
@@ -106,9 +120,9 @@ static unsigned int short_ftape_timestamp(void)
 
 static unsigned int diff(unsigned int t0, unsigned int t1)
 {
-#if defined(__alpha__)
-       return (t1 <= t0) ? t1 + (1UL << 32) - t0 : t1 - t0;
-#elif defined(__i386__) || defined(__x86_64__)
+#if defined(__alpha__) || defined(__x86_64__)
+       return (t1 - t0);
+#elif defined(__i386__)
        /*
         * This is tricky: to work for both short and full ftape_timestamps
         * we'll have to discriminate between these.
@@ -122,9 +136,9 @@ static unsigned int diff(unsigned int t0, unsigned int t1)
 
 static unsigned int usecs(unsigned int count)
 {
-#if defined(__alpha__)
+#if defined(__alpha__) || defined(__x86_64__)
        return (ps_per_cycle * count) / 1000000UL;
-#elif defined(__i386__) || defined(__x86_64__)
+#elif defined(__i386__)
        return (10000 * count) / ((CLOCK_TICK_RATE + 50) / 100);
 #endif
 }
@@ -163,38 +177,13 @@ static void time_inb(void)
 
 static void init_clock(void)
 {
-#if defined(__i386__) || defined(__x86_64__)
-       unsigned int t;
-       int i;
        TRACE_FUN(ft_t_any);
 
-       /*  Haven't studied on why, but there sometimes is a problem
-        *  with the tick timer readout. The two bytes get swapped.
-        *  This hack solves that problem by doing one extra input.
-        */
-       for (i = 0; i < 1000; ++i) {
-               t = short_ftape_timestamp();
-               if (t > LATCH) {
-                       inb_p(0x40);    /* get in sync again */
-                       TRACE(ft_t_warn, "clock counter fixed");
-                       break;
-               }
-       }
+#if defined(__x86_64__)
+       ps_per_cycle = 1000000000UL / cpu_khz;
 #elif defined(__alpha__)
-#if CONFIG_FT_ALPHA_CLOCK == 0
-#error You must define and set CONFIG_FT_ALPHA_CLOCK in 'make config' !
-#endif
        extern struct hwrpb_struct *hwrpb;
-       TRACE_FUN(ft_t_any);
-
-       if (hwrpb->cycle_freq != 0) {
-               ps_per_cycle = (1000*1000*1000*1000UL) / hwrpb->cycle_freq;
-       } else {
-               /*
-                * HELP:  Linux 2.0.x doesn't set cycle_freq on my noname !
-                */
-               ps_per_cycle = (1000*1000*1000*1000UL) / CONFIG_FT_ALPHA_CLOCK;
-       }
+       ps_per_cycle = (1000*1000*1000*1000UL) / hwrpb->cycle_freq;
 #endif
        TRACE_EXIT;
 }
@@ -213,7 +202,7 @@ void ftape_calibrate(char *name,
        unsigned int tc = 0;
        unsigned int count;
        unsigned int time;
-#if defined(__i386__) || defined(__x86_64__)
+#if defined(__i386__)
        unsigned int old_tc = 0;
        unsigned int old_count = 1;
        unsigned int old_time = 1;
@@ -255,7 +244,7 @@ void ftape_calibrate(char *name,
                tc = (1000 * time) / (count - 1);
                TRACE(ft_t_any, "once:%3d us,%6d times:%6d us, TC:%5d ns",
                        usecs(once), count - 1, usecs(multiple), tc);
-#if defined(__alpha__)
+#if defined(__alpha__) || defined(__x86_64__)
                /*
                 * Increase the calibration count exponentially until the
                 * calibration time exceeds 100 ms.
@@ -263,7 +252,7 @@ void ftape_calibrate(char *name,
                if (time >= 100*1000) {
                        break;
                }
-#elif defined(__i386__) || defined(__x86_64__)
+#elif defined(__i386__)
                /*
                 * increase the count until the resulting time nears 2/HZ,
                 * then the tc will drop sharply because we lose LATCH counts.