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>

7 files changed, 117 insertions, 0 deletions

diff --git a/libavutil/cpu.c b/libavutil/cpu.c
index 4627af4f23..63efb97ffd 100644
--- a/libavutil/cpu.c
+++ b/libavutil/cpu.c
@@ -62,6 +62,8 @@ static int get_cpu_flags(void)
         return ff_get_cpu_flags_ppc();
     if (ARCH_X86)
         return ff_get_cpu_flags_x86();
+    if (ARCH_LOONGARCH)
+        return ff_get_cpu_flags_loongarch();
     return 0;
 }
 
@@ -168,6 +170,9 @@ int av_parse_cpu_caps(unsigned *flags, const char *s)
 #elif ARCH_MIPS
         { "mmi",      NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_MMI      },    .unit = "flags" },
         { "msa",      NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_MSA      },    .unit = "flags" },
+#elif ARCH_LOONGARCH
+        { "lsx",      NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_LSX      },    .unit = "flags" },
+        { "lasx",     NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AV_CPU_FLAG_LASX     },    .unit = "flags" },
 #endif
         { NULL },
     };
@@ -253,6 +258,8 @@ size_t av_cpu_max_align(void)
         return ff_get_cpu_max_align_ppc();
     if (ARCH_X86)
         return ff_get_cpu_max_align_x86();
+    if (ARCH_LOONGARCH)
+        return ff_get_cpu_max_align_loongarch();
 
     return 8;
 }
diff --git a/libavutil/cpu.h b/libavutil/cpu.h
index afea0640b4..ae443eccad 100644
--- a/libavutil/cpu.h
+++ b/libavutil/cpu.h
@@ -72,6 +72,10 @@
 #define AV_CPU_FLAG_MMI          (1 << 0)
 #define AV_CPU_FLAG_MSA          (1 << 1)
 
+//Loongarch SIMD extension.
+#define AV_CPU_FLAG_LSX          (1 << 0)
+#define AV_CPU_FLAG_LASX         (1 << 1)
+
 /**
  * Return the flags which specify extensions supported by the CPU.
  * The returned value is affected by av_force_cpu_flags() if that was used
diff --git a/libavutil/cpu_internal.h b/libavutil/cpu_internal.h
index 889764320b..e207b2d480 100644
--- a/libavutil/cpu_internal.h
+++ b/libavutil/cpu_internal.h
@@ -46,11 +46,13 @@ int ff_get_cpu_flags_aarch64(void);
 int ff_get_cpu_flags_arm(void);
 int ff_get_cpu_flags_ppc(void);
 int ff_get_cpu_flags_x86(void);
+int ff_get_cpu_flags_loongarch(void);
 
 size_t ff_get_cpu_max_align_mips(void);
 size_t ff_get_cpu_max_align_aarch64(void);
 size_t ff_get_cpu_max_align_arm(void);
 size_t ff_get_cpu_max_align_ppc(void);
 size_t ff_get_cpu_max_align_x86(void);
+size_t ff_get_cpu_max_align_loongarch(void);
 
 #endif /* AVUTIL_CPU_INTERNAL_H */
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 */
diff --git a/libavutil/tests/cpu.c b/libavutil/tests/cpu.c
index c853371fb3..0a6c0cd32e 100644
--- a/libavutil/tests/cpu.c
+++ b/libavutil/tests/cpu.c
@@ -77,6 +77,9 @@ static const struct {
     { AV_CPU_FLAG_BMI2,      "bmi2"       },
     { AV_CPU_FLAG_AESNI,     "aesni"      },
     { AV_CPU_FLAG_AVX512,    "avx512"     },
+#elif ARCH_LOONGARCH
+    { AV_CPU_FLAG_LSX,       "lsx"        },
+    { AV_CPU_FLAG_LASX,      "lasx"       },
 #endif
     { 0 }
 };