[PATCH v2 4/5] wineboot: Remove dead TSC calibration code.

[Marc-Aurel Zent]

From: Marc-Aurel Zent

---
 programs/wineboot/wineboot.c | 111 ++++++++++++-----------------------
 1 file changed, 36 insertions(+), 75 deletions(-)

diff --git a/programs/wineboot/wineboot.c b/programs/wineboot/wineboot.c
index e7869eb64f4..a19046a6439 100644
--- a/programs/wineboot/wineboot.c
+++ b/programs/wineboot/wineboot.c
@@ -245,90 +245,51 @@ static void initialize_xstate_features(struct _KUSER_SHARED_DATA *data)
 static UINT64 read_tsc_frequency( BOOL has_rdtscp )
 {
     UINT64 freq = 0;
+    LONGLONG time0, time1, tsc0, tsc1, tsc2, tsc3, freq0, freq1, error;
+    unsigned int aux;
+    UINT retries = 50;
+    int regs[4];

-/* FIXME: Intel provides TSC freq in some CPUID but it's been slightly broken,
-   fix it properly and test it on real Intel hardware */
-
-#if 0
-    int regs[4], cpuid_level, tmp;
-    UINT64 denom, numer;
-
-    __cpuid( regs, 0 );
-    tmp = regs[2];
-    regs[2] = regs[3];
-    regs[3] = tmp;
-
-    /* only available on some intel CPUs */
-    if (memcmp( regs + 1, "GenuineIntel", 12 )) freq = 0;
-    else if ((cpuid_level = regs[0]) < 0x15) freq = 0;
-    else
+    do
     {
-        __cpuid( regs, 0x15 );
-        if (!(denom = regs[0]) || !(numer = regs[1])) freq = 0;
+        if (has_rdtscp)
+        {
+            tsc0 = __rdtscp( &aux );
+            time0 = RtlGetSystemTimePrecise();
+            tsc1 = __rdtscp( &aux );
+            Sleep( 1 );
+            tsc2 = __rdtscp( &aux );
+            time1 = RtlGetSystemTimePrecise();
+            tsc3 = __rdtscp( &aux );
+        }
         else
         {
-            if ((freq = regs[2])) freq = freq * numer / denom;
-            else if (cpuid_level >= 0x16)
-            {
-                __cpuid( regs, 0x16 ); /* eax is base freq in MHz */
-                freq = regs[0] * (UINT64)1000000;
-            }
-            else freq = 0;
+            tsc0 = __rdtsc(); __cpuid( regs, 0 );
+            time0 = RtlGetSystemTimePrecise();
+            tsc1 = __rdtsc(); __cpuid( regs, 0 );
+            Sleep(1);
+            tsc2 = __rdtsc(); __cpuid( regs, 0 );
+            time1 = RtlGetSystemTimePrecise();
+            tsc3 = __rdtsc(); __cpuid( regs, 0 );
         }

-        if (!freq) WARN( "Failed to read TSC frequency from CPUID, falling back to calibration.\n" );
-        else TRACE( "TSC frequency read from CPUID, found %I64u Hz\n", freq );
+        freq0 = (tsc2 - tsc0) * 10000000 / (time1 - time0);
+        freq1 = (tsc3 - tsc1) * 10000000 / (time1 - time0);
+        error = llabs( (freq1 - freq0) * 1000000 / min( freq1, freq0 ) );
     }
-#endif
+    while (error > 500 && --retries);

-    if (freq == 0)
+    if (!retries)
     {
-        LONGLONG time0, time1, tsc0, tsc1, tsc2, tsc3, freq0, freq1, error;
-        unsigned int aux;
-        UINT retries = 50;
-        int regs[4];
-
-        do
-        {
-            if (has_rdtscp)
-            {
-                tsc0 = __rdtscp( &aux );
-                time0 = RtlGetSystemTimePrecise();
-                tsc1 = __rdtscp( &aux );
-                Sleep( 1 );
-                tsc2 = __rdtscp( &aux );
-                time1 = RtlGetSystemTimePrecise();
-                tsc3 = __rdtscp( &aux );
-            }
-            else
-            {
-                tsc0 = __rdtsc(); __cpuid( regs, 0 );
-                time0 = RtlGetSystemTimePrecise();
-                tsc1 = __rdtsc(); __cpuid( regs, 0 );
-                Sleep(1);
-                tsc2 = __rdtsc(); __cpuid( regs, 0 );
-                time1 = RtlGetSystemTimePrecise();
-                tsc3 = __rdtsc(); __cpuid( regs, 0 );
-            }
-
-            freq0 = (tsc2 - tsc0) * 10000000 / (time1 - time0);
-            freq1 = (tsc3 - tsc1) * 10000000 / (time1 - time0);
-            error = llabs( (freq1 - freq0) * 1000000 / min( freq1, freq0 ) );
-        }
-        while (error > 500 && --retries);
-
-        if (!retries)
-        {
-            FIXME( "TSC frequency calibration failed, unstable TSC?");
-            FIXME( "time0 %I64u ns, time1 %I64u ns\n", time0 * 100, time1 * 100 );
-            FIXME( "tsc2 - tsc0 %I64u, tsc3 - tsc1 %I64u\n", tsc2 - tsc0, tsc3 - tsc1 );
-            FIXME( "freq0 %I64u Hz, freq2 %I64u Hz, error %I64u ppm\n", freq0, freq1, error );
-        }
-        else
-        {
-            freq = (freq0 + freq1) / 2;
-            TRACE( "TSC frequency calibration complete, found %I64u Hz\n", freq );
-        }
+        FIXME( "TSC frequency calibration failed, unstable TSC?");
+        FIXME( "time0 %I64u ns, time1 %I64u ns\n", time0 * 100, time1 * 100 );
+        FIXME( "tsc2 - tsc0 %I64u, tsc3 - tsc1 %I64u\n", tsc2 - tsc0, tsc3 - tsc1 );
+        FIXME( "freq0 %I64u Hz, freq2 %I64u Hz, error %I64u ppm\n", freq0, freq1, error );
+    }
+    else
+    {
+        freq = (freq0 + freq1) / 2;
+        TRACE( "TSC frequency calibration complete, found %I64u Hz\n", freq );
     }

return freq;