Try modified version for cpuspeed which gives the correct result

1 files changed, 23 insertions, 21 deletions

diff --git a/efi_memtest/memtest86+/efi/init.c b/efi_memtest/memtest86+/efi/init.c
index 6434b5a..2756838 100644
--- a/efi_memtest/memtest86+/efi/init.c
+++ b/efi_memtest/memtest86+/efi/init.c
@@ -1211,8 +1211,8 @@ static int cpuspeed(void)
 	}
 	
 	int loops;
-    // TODO int stlow, sthigh; ulong or int?
-	// TODO ulong end_low, end_high;
+    int stlow, sthigh; // TODO ulong or int?
+	int end_low, end_high; // TODO ulong or int?
 
 	if (cpu_id.fid.bits.rdtsc == 0 ) {
 		return(-1);
@@ -1226,20 +1226,6 @@ static int cpuspeed(void)
 
  	asm __volatile__ ("rdtsc":"=a" (stlow),"=d" (sthigh));
 
-    if (logflag) {
-        char log[28] = "stlow = ";
-        int length = 8;
-        int_to_charr(stlow, log, &length);
-        print_log(log, length);
-    }
-
-    if (logflag) {
-        char log[29] = "sthigh = ";
-        int length = 9;
-        int_to_charr(stlow, log, &length);
-        print_log(log, length);
-    }
-
 	loops = 0;
 	do {
 		loops++;
@@ -1254,20 +1240,34 @@ static int cpuspeed(void)
 		:"=a" (end_low), "=d" (end_high)
 	);*/
 
-   /* asm __volatile__ (
+    /*asm __volatile__ (
         "rdtsc\n\t" \
-        "subq %0, %%rax\n\t" \
-        "sbbq %1, %%rdx\n\t" \
+        "subl %0, %%eax\n\t" \
+        "sbbl %1, %%edx\n\t" \
         :"=a" (end_low), "=d" (end_high)
         :"r" (stlow), "r" (sthigh)
     );*/
 
-     asm __volatile__ (
-        "rdtsc\n\t" // TODO remove
+    asm __volatile__ (
+        "rdtsc"
         :"=a" (end_low), "=d" (end_high)
     );
 
     if (logflag) {
+        char log[28] = "stlow = ";
+        int length = 8;
+        int_to_charr(stlow, log, &length);
+        print_log(log, length);
+    }
+
+    if (logflag) {
+        char log[29] = "sthigh = ";
+        int length = 9;
+        int_to_charr(sthigh, log, &length);
+        print_log(log, length);
+    }
+
+    if (logflag) {
         char log[30] = "end_low = ";
         int length = 10;
         int_to_charr(end_low, log, &length);
@@ -1281,6 +1281,8 @@ static int cpuspeed(void)
         print_log(log, length);
     }
 
+    end_low -= stlow; // TODO remember the carry flag
+
 	/* Make sure we have a credible result */
 	if (loops < 4 || end_low < 50000) {
 		return(-1);