Introduce and use cache-utils.[ch]

Thanks to Segher Boessenkool and Holis Blanchard.

AIX and Darwin cache inquiry:
http://gcc.gnu.org/ml/gcc-patches/2007-08/msg00388.html

Auxiliary vectors:
http://manugarg.googlepages.com/aboutelfauxiliaryvectors

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5973 c046a42c-6fe2-441c-8c8c-71466251a162
diff --git a/cache-utils.c b/cache-utils.c
new file mode 100644
index 0000000..0b4a5acb
--- /dev/null
+++ b/cache-utils.c
@@ -0,0 +1,68 @@
+#include "cache-utils.h"
+
+#ifdef __powerpc__
+struct qemu_cache_conf qemu_cache_conf = {
+    .dcache_bsize = 16,
+    .icache_bsize = 16
+};
+
+#if defined _AIX
+#include <sys/systemcfg.h>
+
+static void ppc_init_cacheline_sizes(void)
+{
+    qemu_cache_conf.icache_bsize = _system_configuration.icache_line;
+    qemu_cache_conf.dcache_bsize = _system_configuration.dcache_line;
+}
+
+#elif defined __linux__
+#include <linux/auxvec.h>
+
+static void ppc_init_cacheline_sizes(char **envp)
+{
+    unsigned long *auxv;
+
+    while (*envp++);
+
+    for (auxv = (unsigned long *) envp; *auxv != AT_NULL; auxv += 2) {
+        switch (*auxv) {
+        case AT_DCACHEBSIZE: qemu_cache_conf.dcache_bsize = auxv[1]; break;
+        case AT_ICACHEBSIZE: qemu_cache_conf.icache_bsize = auxv[1]; break;
+        default: break;
+        }
+    }
+}
+
+#elif defined __APPLE__
+#include <sys/types.h>
+#include <sys/sysctl.h>
+
+static void ppc_init_cacheline_sizes(void)
+{
+    size_t len;
+    unsigned cacheline;
+    int name[2] = { CTL_HW, HW_CACHELINE };
+
+    if (sysctl(name, 2, &cacheline, &len, NULL, 0)) {
+        perror("sysctl CTL_HW HW_CACHELINE failed");
+    } else {
+        qemu_cache_conf.dcache_bsize = cacheline;
+        qemu_cache_conf.icache_bsize = cacheline;
+    }
+}
+#endif
+
+#ifdef __linux__
+void qemu_cache_utils_init(char **envp)
+{
+    ppc_init_cacheline_sizes(envp);
+}
+#else
+void qemu_cache_utils_init(char **envp)
+{
+    (void) envp;
+    ppc_init_cacheline_sizes();
+}
+#endif
+
+#endif /* __powerpc__ */