Prepare for hardware feature detection on other platforms.

* configure.ac (GCRYPT_HWF_MODULES): New.
(HAVE_CPU_ARCH_X86, HAVE_CPU_ARCH_ALPHA, HAVE_CPU_ARCH_SPARC)
(HAVE_CPU_ARCH_MIPS, HAVE_CPU_ARCH_M68K, HAVE_CPU_ARCH_PPC)
(HAVE_CPU_ARCH_ARM): New AC_DEFINEs.
* mpi/config.links (mpi_cpu_arch): New.
* src/global.c (print_config): Print new tag "cpu-arch".
* src/Makefile.am (libgcrypt_la_SOURCES): Add hwf-common.h
(EXTRA_libgcrypt_la_SOURCES): New.
(gcrypt_hwf_modules): New.
(libgcrypt_la_DEPENDENCIES, libgcrypt_la_LIBADD): Add that one.
* src/hwfeatures.c: Factor most code out to ...
* src/hwf-x86.c: New file.
(detect_x86_gnuc): Return the feature vector.
(_gcry_hwf_detect_x86): New.
* src/hwf-common.h: New.
* src/hwfeatures.c (_gcry_detect_hw_features): Dispatch using
HAVE_CPU_ARCH_ macros.

Signed-off-by: Werner Koch <wk@gnupg.org>

1 files changed, 6 insertions, 182 deletions

diff --git a/src/hwfeatures.c b/src/hwfeatures.c
index 62600aa9..87d05d83 100644
--- a/src/hwfeatures.c
+++ b/src/hwfeatures.c
@@ -1,5 +1,6 @@
 /* hwfeatures.c - Detect hardware features.
  * Copyright (C) 2007, 2011  Free Software Foundation, Inc.
+ * Copyright (C) 2012  g10 Code GmbH
  *
  * This file is part of Libgcrypt.
  *
@@ -25,6 +26,8 @@
 #include <unistd.h>
 
 #include "g10lib.h"
+#include "hwf-common.h"
+
 
 /* A bit vector describing the hardware features currently
    available. */
@@ -40,185 +43,6 @@ _gcry_get_hw_features (void)
 }
 
 
-#undef HAS_X86_CPUID
-
-#if defined (__i386__) && SIZEOF_UNSIGNED_LONG == 4 && defined (__GNUC__)
-#define HAS_X86_CPUID 1
-
-static int
-is_cpuid_available(void)
-{
-  int has_cpuid = 0;
-
-  /* Detect the CPUID feature by testing some undefined behaviour (16
-     vs 32 bit pushf/popf). */
-  asm volatile
-    ("pushf\n\t"                 /* Copy flags to EAX.  */
-     "popl %%eax\n\t"
-     "movl %%eax, %%ecx\n\t"     /* Save flags into ECX.  */
-     "xorl $0x200000, %%eax\n\t" /* Toggle ID bit and copy it to the flags.  */
-     "pushl %%eax\n\t"
-     "popf\n\t"
-     "pushf\n\t"                 /* Copy changed flags again to EAX.  */
-     "popl %%eax\n\t"
-     "pushl %%ecx\n\t"           /* Restore flags from ECX.  */
-     "popf\n\t"
-     "xorl %%eax, %%ecx\n\t"     /* Compare flags against saved flags.  */
-     "jz .Lno_cpuid%=\n\t"       /* Toggling did not work, thus no CPUID.  */
-     "movl $1, %0\n"             /* Worked. true -> HAS_CPUID.  */
-     ".Lno_cpuid%=:\n\t"
-     : "+r" (has_cpuid)
-     :
-     : "%eax", "%ecx", "cc"
-     );
-
-  return has_cpuid;
-}
-
-static void
-get_cpuid(unsigned int in, unsigned int *eax, unsigned int *ebx,
-          unsigned int *ecx, unsigned int *edx)
-{
-  unsigned int regs[4];
-
-  asm volatile
-    ("pushl %%ebx\n\t"           /* Save GOT register.  */
-     "cpuid\n\t"
-     "movl %%ebx, %1\n\t"
-     "popl %%ebx\n\t"            /* Restore GOT register. */
-     : "=a" (regs[0]), "=r" (regs[1]), "=c" (regs[2]), "=d" (regs[3])
-     : "0" (in)
-     : "cc"
-     );
-
-  if (eax)
-    *eax = regs[0];
-  if (ebx)
-    *ebx = regs[1];
-  if (ecx)
-    *ecx = regs[2];
-  if (edx)
-    *edx = regs[3];
-}
-#endif /* i386 && GNUC */
-
-
-#if defined (__x86_64__) && defined (__GNUC__)
-#define HAS_X86_CPUID 1
-
-static int
-is_cpuid_available(void)
-{
-  return 1;
-}
-
-static void
-get_cpuid(unsigned int in, unsigned int *eax, unsigned int *ebx,
-          unsigned int *ecx, unsigned int *edx)
-{
-  unsigned int regs[4];
-
-  asm volatile
-    ("cpuid\n\t"
-     : "=a" (regs[0]), "=b" (regs[1]), "=c" (regs[2]), "=d" (regs[3])
-     : "0" (in)
-     : "cc"
-     );
-
-  if (eax)
-    *eax = regs[0];
-  if (ebx)
-    *ebx = regs[1];
-  if (ecx)
-    *ecx = regs[2];
-  if (edx)
-    *edx = regs[3];
-}
-#endif /* x86-64 && GNUC */
-
-
-#ifdef HAS_X86_CPUID
-static void
-detect_x86_gnuc (void)
-{
-  char vendor_id[12+1];
-  unsigned int features;
-
-  if (!is_cpuid_available())
-    return;
-
-  get_cpuid(0, NULL,
-            (unsigned int *)&vendor_id[0],
-            (unsigned int *)&vendor_id[8],
-            (unsigned int *)&vendor_id[4]);
-  vendor_id[12] = 0;
-
-  if (0)
-    ; /* Just to make "else if" and ifdef macros look pretty.  */
-#ifdef ENABLE_PADLOCK_SUPPORT
-  else if (!strcmp (vendor_id, "CentaurHauls"))
-    {
-      /* This is a VIA CPU.  Check what PadLock features we have.  */
-
-      /* Check for extended centaur (EAX).  */
-      get_cpuid(0xC0000000, &features, NULL, NULL, NULL);
-
-      /* Has extended centaur features? */
-      if (features > 0xC0000000)
-        {
-           /* Ask for the extended feature flags (EDX). */
-           get_cpuid(0xC0000001, NULL, NULL, NULL, &features);
-
-           /* Test bits 2 and 3 to see whether the RNG exists and is enabled. */
-           if ((features & 0x0C) == 0x0C)
-             hw_features |= HWF_PADLOCK_RNG;
-
-           /* Test bits 6 and 7 to see whether the ACE exists and is enabled. */
-           if ((features & 0xC0) == 0xC0)
-             hw_features |= HWF_PADLOCK_AES;
-
-           /* Test bits 10 and 11 to see whether the PHE exists and is
-              enabled.  */
-           if ((features & 0xC00) == 0xC00)
-             hw_features |= HWF_PADLOCK_SHA;
-
-           /* Test bits 12 and 13 to see whether the MONTMUL exists and is
-              enabled.  */
-           if ((features & 0x3000) == 0x3000)
-             hw_features |= HWF_PADLOCK_MMUL;
-        }
-    }
-#endif /*ENABLE_PADLOCK_SUPPORT*/
-  else if (!strcmp (vendor_id, "GenuineIntel"))
-    {
-      /* This is an Intel CPU.  */
-    }
-  else if (!strcmp (vendor_id, "AuthenticAMD"))
-    {
-      /* This is an AMD CPU.  */
-    }
-
-  /* Detect Intel features, that might also be supported by other
-     vendors.  */
-
-  /* Get CPU info and Intel feature flags (ECX).  */
-  get_cpuid(1, NULL, NULL, &features, NULL);
-
-#ifdef ENABLE_AESNI_SUPPORT
-  /* Test bit 25 for AES-NI.  */
-  if (features & 0x02000000)
-     hw_features |= HWF_INTEL_AESNI;
-#endif /*ENABLE_AESNI_SUPPORT*/
-#ifdef ENABLE_DRNG_SUPPORT
-  /* Test bit 30 for RDRAND.  */
-  if (features & 0x40000000)
-     hw_features |= HWF_INTEL_RDRAND;
-#endif /*ENABLE_DRNG_SUPPORT*/
-
-}
-#endif /* HAS_X86_CPUID */
-
-
 /* Detect the available hardware features.  This function is called
    once right at startup and we assume that no other threads are
    running.  */
@@ -230,11 +54,11 @@ _gcry_detect_hw_features (unsigned int disabled_features)
   if (fips_mode ())
     return; /* Hardware support is not to be evaluated.  */
 
-#if HAS_X86_CPUID
+#if defined (HAVE_CPU_ARCH_X86)
   {
-    detect_x86_gnuc ();
+    hw_features = _gcry_hwf_detect_x86 ();
   }
-#endif /* HAS_X86_CPUID */
+#endif /* HAVE_CPU_ARCH_X86 */
 
   hw_features &= ~disabled_features;
 }