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-rw-r--r--third_party/aom/aom_ports/ppc_cpudetect.c82
1 files changed, 82 insertions, 0 deletions
diff --git a/third_party/aom/aom_ports/ppc_cpudetect.c b/third_party/aom/aom_ports/ppc_cpudetect.c
new file mode 100644
index 0000000000..82b4f58ccc
--- /dev/null
+++ b/third_party/aom/aom_ports/ppc_cpudetect.c
@@ -0,0 +1,82 @@
+/*
+ * Copyright (c) 2018, Alliance for Open Media. All rights reserved
+ *
+ * This source code is subject to the terms of the BSD 2 Clause License and
+ * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
+ * was not distributed with this source code in the LICENSE file, you can
+ * obtain it at www.aomedia.org/license/software. If the Alliance for Open
+ * Media Patent License 1.0 was not distributed with this source code in the
+ * PATENTS file, you can obtain it at www.aomedia.org/license/patent.
+ */
+
+#include <fcntl.h>
+#include <unistd.h>
+#include <stdint.h>
+#include <asm/cputable.h>
+#include <linux/auxvec.h>
+
+#include "config/aom_config.h"
+
+#include "aom_ports/ppc.h"
+
+#if CONFIG_RUNTIME_CPU_DETECT
+static int cpu_env_flags(int *flags) {
+ char *env;
+ env = getenv("AOM_SIMD_CAPS");
+ if (env && *env) {
+ *flags = (int)strtol(env, NULL, 0);
+ return 0;
+ }
+ *flags = 0;
+ return -1;
+}
+
+static int cpu_env_mask(void) {
+ char *env;
+ env = getenv("AOM_SIMD_CAPS_MASK");
+ return env && *env ? (int)strtol(env, NULL, 0) : ~0;
+}
+
+int ppc_simd_caps(void) {
+ int flags;
+ int mask;
+ int fd;
+ ssize_t count;
+ unsigned int i;
+ uint64_t buf[64];
+
+ // If VPX_SIMD_CAPS is set then allow only those capabilities.
+ if (!cpu_env_flags(&flags)) {
+ return flags;
+ }
+
+ mask = cpu_env_mask();
+
+ fd = open("/proc/self/auxv", O_RDONLY);
+ if (fd < 0) {
+ return 0;
+ }
+
+ while ((count = read(fd, buf, sizeof(buf))) > 0) {
+ for (i = 0; i < (count / sizeof(*buf)); i += 2) {
+ if (buf[i] == AT_HWCAP) {
+#if HAVE_VSX
+ if (buf[i + 1] & PPC_FEATURE_HAS_VSX) {
+ flags |= HAS_VSX;
+ }
+#endif // HAVE_VSX
+ goto out_close;
+ } else if (buf[i] == AT_NULL) {
+ goto out_close;
+ }
+ }
+ }
+out_close:
+ close(fd);
+ return flags & mask;
+}
+#else
+// If there is no RTCD the function pointers are not used and can not be
+// changed.
+int ppc_simd_caps(void) { return 0; }
+#endif // CONFIG_RUNTIME_CPU_DETECT