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-rw-r--r--sysdeps/unix/sysv/linux/alpha/sysconf.c127
1 files changed, 127 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/alpha/sysconf.c b/sysdeps/unix/sysv/linux/alpha/sysconf.c
new file mode 100644
index 0000000000..467c5bb5f2
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/alpha/sysconf.c
@@ -0,0 +1,127 @@
+/* Copyright (C) 2004-2014 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <assert.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+
+static long int linux_sysconf (int name);
+
+#define CSHAPE(totalsize, linesize, assoc) \
+  ((totalsize & ~0xff) | (linesize << 4) | assoc)
+
+extern long __libc_alpha_cache_shape[4];
+
+/* Get the value of the system variable NAME.  */
+long int
+__sysconf (int name)
+{
+  long shape, index;
+
+  /* We only handle the cache information here (for now).  */
+  if (name < _SC_LEVEL1_ICACHE_SIZE || name > _SC_LEVEL4_CACHE_LINESIZE)
+    return linux_sysconf (name);
+
+  /* No Alpha has L4 caches.  */
+  if (name >= _SC_LEVEL4_CACHE_SIZE)
+    return -1;
+
+  index = (name - _SC_LEVEL1_ICACHE_SIZE) / 3;
+  shape = __libc_alpha_cache_shape[index];
+  if (shape == -2)
+    {
+      long shape_l1i, shape_l1d, shape_l2, shape_l3 = -1;
+
+      /* ??? In the cases below for which we do not know L1 cache sizes,
+	 we could do timings to measure sizes.  But for the Bcache, it's
+	 generally big enough that (without additional help) TLB effects
+	 get in the way.  We'd either need to be able to allocate large
+	 pages or have the kernel do the timings from KSEG.  Fortunately,
+	 kernels beginning with 2.6.5 will pass us this info in auxvec.  */
+
+      switch (__builtin_alpha_implver ())
+	{
+	case 0: /* EV4 */
+	  /* EV4/LCA45 had 8k L1 caches; EV45 had 16k L1 caches.  */
+	  /* EV4/EV45 had 128k to 16M 32-byte direct Bcache.  LCA45
+	     had 64k to 8M 8-byte direct Bcache.  Can't tell.  */
+	  shape_l1i = shape_l1d = shape_l2 = CSHAPE (0, 5, 1);
+	  break;
+
+	case 1: /* EV5 */
+	  if (__builtin_alpha_amask (1 << 8))
+	    {
+	      /* MAX insns not present; either EV5 or EV56.  */
+	      shape_l1i = shape_l1d = CSHAPE(8*1024, 5, 1);
+	      /* ??? L2 and L3 *can* be configured as 32-byte line.  */
+	      shape_l2 = CSHAPE (96*1024, 6, 3);
+	      /* EV5/EV56 has 1M to 16M Bcache.  */
+	      shape_l3 = CSHAPE (0, 6, 1);
+	    }
+	  else
+	    {
+	      /* MAX insns present; either PCA56 or PCA57.  */
+	      /* PCA56 had 16k 64-byte cache; PCA57 had 32k Icache.  */
+	      /* PCA56 had 8k 64-byte cache; PCA57 had 16k Dcache.  */
+	      /* PCA5[67] had 512k to 4M Bcache.  */
+	      shape_l1i = shape_l1d = shape_l2 = CSHAPE (0, 6, 1);
+	    }
+	  break;
+
+	case 2: /* EV6 */
+	  shape_l1i = shape_l1d = CSHAPE(64*1024, 6, 2);
+	  /* EV6/EV67/EV68* had 1M to 16M Bcache.  */
+	  shape_l2 = CSHAPE (0, 6, 1);
+	  break;
+
+	case 3: /* EV7 */
+	  shape_l1i = shape_l1d = CSHAPE(64*1024, 6, 2);
+	  shape_l2 = CSHAPE(7*1024*1024/4, 6, 7);
+	  break;
+
+	default:
+	  shape_l1i = shape_l1d = shape_l2 = 0;
+	  break;
+	}
+
+      __libc_alpha_cache_shape[0] = shape_l1i;
+      __libc_alpha_cache_shape[1] = shape_l1d;
+      __libc_alpha_cache_shape[2] = shape_l2;
+      __libc_alpha_cache_shape[3] = shape_l3;
+      shape = __libc_alpha_cache_shape[index];
+    }
+
+  if (shape <= 0)
+    return shape;
+
+  switch ((name - _SC_LEVEL1_ICACHE_SIZE) % 3)
+    {
+    case 0: /* total size */
+      return shape & -0x100;
+    case 1: /* associativity */
+      return shape & 0xf;
+    default: /* line size */
+      return 1L << ((shape >> 4) & 0xf);
+    }
+}
+
+/* Now the generic Linux version.  */
+#undef __sysconf
+#define __sysconf static linux_sysconf
+#include <sysdeps/unix/sysv/linux/sysconf.c>