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authorAndroid Build Coastguard Worker <android-build-coastguard-worker@google.com>2023-02-01 18:16:36 +0000
committerAndroid Build Coastguard Worker <android-build-coastguard-worker@google.com>2023-02-01 18:16:36 +0000
commit891eab5d3ef1389ff27447aa19fe36b97e98fd71 (patch)
treeb1549c5eb19c887159bcba9e71b8e63f6ee02273 /vpx_ports/ppc_cpudetect.c
parent6939824c0cf8321a1718973892371085f7b4edff (diff)
parent6f710d29f638dc64370644643d6b2f1ba468deec (diff)
downloadlibvpx-891eab5d3ef1389ff27447aa19fe36b97e98fd71.tar.gz
Snap for 9551305 from 6f710d29f638dc64370644643d6b2f1ba468deec to mainline-tzdata5-release
Change-Id: I3deecb4a87bf823d07abf0c9c522bcd1bc7d8313
Diffstat (limited to 'vpx_ports/ppc_cpudetect.c')
-rw-r--r--vpx_ports/ppc_cpudetect.c80
1 files changed, 80 insertions, 0 deletions
diff --git a/vpx_ports/ppc_cpudetect.c b/vpx_ports/ppc_cpudetect.c
new file mode 100644
index 000000000..374a0271c
--- /dev/null
+++ b/vpx_ports/ppc_cpudetect.c
@@ -0,0 +1,80 @@
+/*
+ * Copyright (c) 2017 The WebM project authors. All Rights Reserved.
+ *
+ * Use of this source code is governed by a BSD-style license
+ * that can be found in the LICENSE file in the root of the source
+ * tree. An additional intellectual property rights grant can be found
+ * in the file PATENTS. All contributing project authors may
+ * be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include <fcntl.h>
+#include <unistd.h>
+#include <stdint.h>
+#include <asm/cputable.h>
+#include <linux/auxvec.h>
+
+#include "./vpx_config.h"
+#include "vpx_ports/ppc.h"
+
+#if CONFIG_RUNTIME_CPU_DETECT
+static int cpu_env_flags(int *flags) {
+ char *env;
+ env = getenv("VPX_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("VPX_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