ARM: Add support for AT_HWCAP2 in _dl_procinfo

Add support for the new HWCAP2 values for ARMv8 added in the
3.15 kernel. Tested using QEMU which supports these extensions.

ChangeLog:

2014-06-25  Will Newton  <will.newton@linaro.org>

	* sysdeps/unix/sysv/linux/arm/dl-procinfo.c
	(_dl_arm_cap_flags): Add HWCAP2 values.
	* sysdeps/unix/sysv/linux/arm/dl-procinfo.h
	(_DL_HWCAP_COUNT): Increase to 37.
	(_DL_HWCAP_LAST): New define.
	(_DL_HWCAP2_LAST): New define.
	(_dl_procinfo): Add support for printing
	AT_HWCAP2 entries.
	(_dl_string_hwcap): Use _dl_hwcap_string.

1 files changed, 38 insertions, 23 deletions

diff --git a/sysdeps/unix/sysv/linux/arm/dl-procinfo.h b/sysdeps/unix/sysv/linux/arm/dl-procinfo.h
index 20a3e92bbb..f7557b9d86 100644
--- a/sysdeps/unix/sysv/linux/arm/dl-procinfo.h
+++ b/sysdeps/unix/sysv/linux/arm/dl-procinfo.h
@@ -23,51 +23,66 @@
 #include <ldsodefs.h>
 #include <sysdep.h>
 
-#define _DL_HWCAP_COUNT 22
+#define _DL_HWCAP_COUNT 37
+
+/* Low 22 bits are allocated in HWCAP.  */
+#define _DL_HWCAP_LAST		21
+
+/* Low 5 bits are allocated in HWCAP2.  */
+#define _DL_HWCAP2_LAST		4
 
 /* The kernel provides platform data but it is not interesting.  */
-#define _DL_HWCAP_PLATFORM 	0
+#define _DL_HWCAP_PLATFORM	0
 
 
+static inline const char *
+__attribute__ ((unused))
+_dl_hwcap_string (int idx)
+{
+  return GLRO(dl_arm_cap_flags)[idx];
+};
+
 static inline int
 __attribute__ ((unused))
 _dl_procinfo (unsigned int type, unsigned long int word)
 {
-  int i;
-
-  /* Fallback to unknown output mechanism.  */
-  if (type == AT_HWCAP2)
-    return -1;
+  switch(type)
+    {
+    case AT_HWCAP:
+      _dl_printf ("AT_HWCAP:       ");
 
-  _dl_printf ("AT_HWCAP:   ");
+      for (int i = 0; i <= _DL_HWCAP_LAST; ++i)
+	if (word & (1 << i))
+	  _dl_printf (" %s", _dl_hwcap_string (i));
+      break;
+    case AT_HWCAP2:
+      {
+	unsigned int offset = _DL_HWCAP_LAST + 1;
 
-  for (i = 0; i < _DL_HWCAP_COUNT; ++i)
-    if (word & (1 << i))
-      _dl_printf (" %s", GLRO(dl_arm_cap_flags)[i]);
+	_dl_printf ("AT_HWCAP2:      ");
 
+	for (int i = 0; i <= _DL_HWCAP2_LAST; ++i)
+	  if (word & (1 << i))
+	    _dl_printf (" %s", _dl_hwcap_string (offset + i));
+	break;
+      }
+    default:
+      /* This should not happen.  */
+      return -1;
+    }
   _dl_printf ("\n");
-
   return 0;
 }
 
-static inline const char *
-__attribute__ ((unused))
-_dl_hwcap_string (int idx)
-{
-  return GLRO(dl_arm_cap_flags)[idx];
-};
-
 #define HWCAP_IMPORTANT		(HWCAP_ARM_VFP | HWCAP_ARM_NEON)
 
 static inline int
 __attribute__ ((unused))
 _dl_string_hwcap (const char *str)
 {
-  int i;
-
-  for (i = 0; i < _DL_HWCAP_COUNT; i++)
+  for (int i = 0; i < _DL_HWCAP_COUNT; i++)
     {
-      if (strcmp (str, GLRO(dl_arm_cap_flags)[i]) == 0)
+      if (strcmp (str, _dl_hwcap_string (i)) == 0)
 	return i;
     }
   return -1;