avutil: [loongarch] Add support for loongarch SIMD.

LSX and LASX is loongarch SIMD extention.
They are enabled by default if compiler support it, and can be disabled
with '--disable-lsx' '--disable-lasx'.

Change-Id: Ie2608ea61dbd9b7fffadbf0ec2348bad6c124476
Reviewed-by: Shiyou Yin <yinshiyou-hf@loongson.cn>
Reviewed-by: guxiwei <guxiwei-hf@loongson.cn>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

3 files changed, 101 insertions, 0 deletions

diff --git a/libavutil/loongarch/Makefile b/libavutil/loongarch/Makefile
new file mode 100644
index 0000000000..2addd9351c
--- /dev/null
+++ b/libavutil/loongarch/Makefile
@@ -0,0 +1 @@
+OBJS += loongarch/cpu.o
diff --git a/libavutil/loongarch/cpu.c b/libavutil/loongarch/cpu.c
new file mode 100644
index 0000000000..e4b240bc44
--- /dev/null
+++ b/libavutil/loongarch/cpu.c
@@ -0,0 +1,69 @@
+/*
+ * Copyright (c) 2020 Loongson Technology Corporation Limited
+ * Contributed by Shiyou Yin <yinshiyou-hf@loongson.cn>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg 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.
+ *
+ * FFmpeg 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 FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <stdint.h>
+#include "cpu.h"
+
+#define LOONGARCH_CFG2 0x2
+#define LOONGARCH_CFG2_LSX    (1 << 6)
+#define LOONGARCH_CFG2_LASX   (1 << 7)
+
+static int cpu_flags_cpucfg(void)
+{
+    int flags = 0;
+    uint32_t cfg2 = 0;
+
+    __asm__ volatile(
+        "cpucfg %0, %1 \n\t"
+        : "+&r"(cfg2)
+        : "r"(LOONGARCH_CFG2)
+    );
+
+    if (cfg2 & LOONGARCH_CFG2_LSX)
+        flags |= AV_CPU_FLAG_LSX;
+
+    if (cfg2 & LOONGARCH_CFG2_LASX)
+        flags |= AV_CPU_FLAG_LASX;
+
+    return flags;
+}
+
+int ff_get_cpu_flags_loongarch(void)
+{
+#if defined __linux__
+    return cpu_flags_cpucfg();
+#else
+    /* Assume no SIMD ASE supported */
+    return 0;
+#endif
+}
+
+size_t ff_get_cpu_max_align_loongarch(void)
+{
+    int flags = av_get_cpu_flags();
+
+    if (flags & AV_CPU_FLAG_LASX)
+        return 32;
+    if (flags & AV_CPU_FLAG_LSX)
+        return 16;
+
+    return 8;
+}
diff --git a/libavutil/loongarch/cpu.h b/libavutil/loongarch/cpu.h
new file mode 100644
index 0000000000..1a445c69bc
--- /dev/null
+++ b/libavutil/loongarch/cpu.h
@@ -0,0 +1,31 @@
+/*
+ * Copyright (c) 2020 Loongson Technology Corporation Limited
+ * Contributed by Shiyou Yin <yinshiyou-hf@loongson.cn>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg 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.
+ *
+ * FFmpeg 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 FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef AVUTIL_LOONGARCH_CPU_H
+#define AVUTIL_LOONGARCH_CPU_H
+
+#include "libavutil/cpu.h"
+#include "libavutil/cpu_internal.h"
+
+#define have_lsx(flags) CPUEXT(flags, LSX)
+#define have_lasx(flags) CPUEXT(flags, LASX)
+
+#endif /* AVUTIL_LOONGARCH_CPU_H */