From bbeb4d255c100d0db823a8d2084358c17edc66a4 Mon Sep 17 00:00:00 2001
From: wangguofeng <wangguofeng@loongson.cn>
Date: Thu, 12 Aug 2021 10:00:08 +0800
Subject: [PATCH 1/3] arch: add loongarch support.

This patch adds support for loongarch for fio.  This is tested by building
FIO on an loongarch Debian 10 system.

Signed-off-by: wangguofeng <wangguofeng@loongson.cn>
---
 arch/arch-loongarch.h | 37 +++++++++++++++++++++++++++++++++++++
 arch/arch.h           |  3 +++
 os/os-linux-syscall.h |  4 ++--
 3 files changed, 42 insertions(+), 2 deletions(-)
 create mode 100644 arch/arch-loongarch.h

diff --git a/arch/arch-loongarch.h b/arch/arch-loongarch.h
new file mode 100644
index 0000000000..1f1b8a0034
--- /dev/null
+++ b/arch/arch-loongarch.h
@@ -0,0 +1,37 @@
+#ifndef ARCH_LOONGARCH_H
+#define ARCH_LOONGARCH_H
+
+#define FIO_ARCH	(arch_loongarch)
+
+#define read_barrier()		__asm__ __volatile__("dbar 0": : :"memory")
+#define write_barrier()		__asm__ __volatile__("dbar 0": : :"memory")
+#define nop			__asm__ __volatile__("nop")
+
+#if __loongarch_xlen == 64
+#define CTZ "ctz.d"
+#define CTO "cto.d"
+#else
+#define CTZ "ctz.w"
+#define CTO "cto.w"
+#endif
+static inline int arch_ffz(unsigned long bitmask)
+{
+	unsigned long count;
+	if (~bitmask == 0)	/* ffz() in lib/ffz.h does this. */
+		return 63;
+
+	__asm__ __volatile__ (CTZ " %0, %1\n\t"
+			      "bnez %0, 0f\n\t"
+			      CTO " %0, %1\n\t"
+			      "b 1f\n\t"
+			      "0: move %0, $zero\n\t"
+			      "1:\n\t"
+			      :"=&r"(count)
+			      :"r"(bitmask));
+
+	return count;
+}
+
+#define ARCH_HAVE_FFZ
+
+#endif
diff --git a/arch/arch.h b/arch/arch.h
index a25779d4fd..19bce09a7e 100644
--- a/arch/arch.h
+++ b/arch/arch.h
@@ -19,6 +19,7 @@ enum {
 	arch_hppa,
 	arch_mips,
 	arch_aarch64,
+	arch_loongarch,
 
 	arch_generic,
 
@@ -77,6 +78,8 @@ extern unsigned long arch_flags;
 #include "arch-hppa.h"
 #elif defined(__aarch64__)
 #include "arch-aarch64.h"
+#elif defined(__loongarch__)
+#include "arch-loongarch.h"
 #else
 #warning "Unknown architecture, attempting to use generic model."
 #include "arch-generic.h"
diff --git a/os/os-linux-syscall.h b/os/os-linux-syscall.h
index c399b2fa99..a43e394e65 100644
--- a/os/os-linux-syscall.h
+++ b/os/os-linux-syscall.h
@@ -263,8 +263,8 @@
 #define __NR_sys_vmsplice	294
 #endif
 
-/* Linux syscalls for aarch64 */
-#elif defined(ARCH_AARCH64_H)
+/* Linux syscalls for aarch64 and loongarch */
+#elif defined(ARCH_AARCH64_H) || defined(ARCH_LOONGARCH_H)
 #ifndef __NR_ioprio_set
 #define __NR_ioprio_set		30
 #define __NR_ioprio_get		31

From 5accd4b7b44204a696e047d7e9c194cb01682e06 Mon Sep 17 00:00:00 2001
From: wangguofeng <wangguofeng@loongson.cn>
Date: Mon, 16 Aug 2021 14:20:07 +0800
Subject: [PATCH 2/3] arch: remove loongarch 32bit ffz

---
 arch/arch-loongarch.h | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/arch/arch-loongarch.h b/arch/arch-loongarch.h
index 1f1b8a0034..474f70deb8 100644
--- a/arch/arch-loongarch.h
+++ b/arch/arch-loongarch.h
@@ -10,10 +10,6 @@
 #if __loongarch_xlen == 64
 #define CTZ "ctz.d"
 #define CTO "cto.d"
-#else
-#define CTZ "ctz.w"
-#define CTO "cto.w"
-#endif
 static inline int arch_ffz(unsigned long bitmask)
 {
 	unsigned long count;
@@ -35,3 +31,5 @@ static inline int arch_ffz(unsigned long bitmask)
 #define ARCH_HAVE_FFZ
 
 #endif
+
+#endif

From 32560c7cf51cb179d1a892263849d60cbe29d3f6 Mon Sep 17 00:00:00 2001
From: wangguofeng <wangguofeng@loongson.cn>
Date: Mon, 16 Aug 2021 17:55:19 +0800
Subject: [PATCH 3/3] arch: add loongarch 32bit ffz

---
 arch/arch-loongarch.h | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/arch/arch-loongarch.h b/arch/arch-loongarch.h
index 474f70deb8..e1248fae2f 100644
--- a/arch/arch-loongarch.h
+++ b/arch/arch-loongarch.h
@@ -7,14 +7,19 @@
 #define write_barrier()		__asm__ __volatile__("dbar 0": : :"memory")
 #define nop			__asm__ __volatile__("nop")
 
-#if __loongarch_xlen == 64
-#define CTZ "ctz.d"
-#define CTO "cto.d"
 static inline int arch_ffz(unsigned long bitmask)
 {
 	unsigned long count;
 	if (~bitmask == 0)	/* ffz() in lib/ffz.h does this. */
+#if __loongarch_xlen == 64
 		return 63;
+#define CTZ "ctz.d"
+#define CTO "cto.d"
+#else
+		return 31;
+#define CTZ "ctz.w"
+#define CTO "cto.w"
+#endif
 
 	__asm__ __volatile__ (CTZ " %0, %1\n\t"
 			      "bnez %0, 0f\n\t"
@@ -31,5 +36,3 @@ static inline int arch_ffz(unsigned long bitmask)
 #define ARCH_HAVE_FFZ
 
 #endif
-
-#endif