s390: calculate loops_per_jiffies with fp instructions

Implement calculation of loops_per_jiffies with fp instructions which
are available on all 64 bit machines.
To save and restore floating point register context use the new vx support
functions.

Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

diff --git a/arch/s390/kernel/sysinfo.c b/arch/s390/kernel/sysinfo.c
index f7dba3887a54556aa51eed974b79834e2947280b..96d81502e599db25100af720ef4496952e7a0acd 100644 (file)
--- a/arch/s390/kernel/sysinfo.c
+++ b/arch/s390/kernel/sysinfo.c
@@ -16,11 +16,7 @@
 #include <asm/sysinfo.h>
 #include <asm/cpcmd.h>
 #include <asm/topology.h>
-
-/* Sigh, math-emu. Don't ask. */
-#include <asm/sfp-util.h>
-#include <math-emu/soft-fp.h>
-#include <math-emu/single.h>
+#include <asm/fpu/api.h>
 
 int topology_max_mnest;
 
@@ -414,10 +410,8 @@ subsys_initcall(create_proc_service_level);
 void s390_adjust_jiffies(void)
 {
        struct sysinfo_1_2_2 *info;
-       const unsigned int fmil = 0x4b189680;   /* 1e7 as 32-bit float. */
-       FP_DECL_S(SA); FP_DECL_S(SB); FP_DECL_S(SR);
-       FP_DECL_EX;
-       unsigned int capability;
+       unsigned long capability;
+       struct kernel_fpu fpu;
 
        info = (void *) get_zeroed_page(GFP_KERNEL);
        if (!info)
@@ -433,15 +427,25 @@ void s390_adjust_jiffies(void)
                 * higher cpu capacity. Bogomips are the other way round.
                 * To get to a halfway suitable number we divide 1e7
                 * by the cpu capability number. Yes, that means a floating
-                * point division .. math-emu here we come :-)
+                * point division ..
                 */
-               FP_UNPACK_SP(SA, &fmil);
-               if ((info->capability >> 23) == 0)
-                       FP_FROM_INT_S(SB, (long) info->capability, 64, long);
-               else
-                       FP_UNPACK_SP(SB, &info->capability);
-               FP_DIV_S(SR, SA, SB);
-               FP_TO_INT_S(capability, SR, 32, 0);
+               kernel_fpu_begin(&fpu, KERNEL_FPR);
+               asm volatile(
+                       "       sfpc    %3\n"
+                       "       l       %0,%1\n"
+                       "       tmlh    %0,0xff80\n"
+                       "       jnz     0f\n"
+                       "       cefbr   %%f2,%0\n"
+                       "       j       1f\n"
+                       "0:     le      %%f2,%1\n"
+                       "1:     cefbr   %%f0,%2\n"
+                       "       debr    %%f0,%%f2\n"
+                       "       cgebr   %0,5,%%f0\n"
+                       : "=&d" (capability)
+                       : "Q" (info->capability), "d" (10000000), "d" (0)
+                       : "cc"
+                       );
+               kernel_fpu_end(&fpu);
        } else
                /*
                 * Really old machine without stsi block for basic