From 00c09535b6e3501d0ee993a1b7c8f19150d76209 Mon Sep 17 00:00:00 2001
From: Zhang Wenlong <zhangwenlong@loongson.cn>
Date: Wed, 8 Dec 2021 17:39:46 +0800
Subject: [PATCH] Introduce basic loongarch64 support

Signed-off-by: Zhang Wenlong <zhangwenlong@loongson.cn>
---
 Makefile               |  8 ++++++++
 ld.hugetlbfs           |  4 ++--
 sys-elf64-loongarch.S  | 24 ++++++++++++++++++++++++
 tests/icache-hygiene.c |  2 +-
 4 files changed, 35 insertions(+), 3 deletions(-)
 create mode 100644 sys-elf64-loongarch.S

diff --git a/Makefile b/Makefile
index 8b73523..88dbf77 100644
--- a/Makefile
+++ b/Makefile
@@ -117,6 +117,13 @@ ELF64 = elf_riscv64
 TMPLIB64 = lib64
 CUSTOM_LDSCRIPTS = no
 else
+ifeq ($(ARCH),loongarch64)
+CC64 = $(CC)
+ELF64 = elf64-loongarch
+TMPLIB64 = lib64
+TMPLIB32 = lib
+CUSTOM_LDSCRIPTS = no
+else
 $(error "Unrecognized architecture ($(ARCH))")
 endif
 endif
@@ -130,6 +137,7 @@ endif
 endif
 endif
 endif
+endif
 
 ifdef CC32
 OBJDIRS += obj32
diff --git a/ld.hugetlbfs b/ld.hugetlbfs
index 5e4e497..0157114 100755
--- a/ld.hugetlbfs
+++ b/ld.hugetlbfs
@@ -117,7 +117,7 @@ elf64ppc|elf64lppc)
 	fi ;;
 elf_i386|elf_x86_64)	HPAGE_SIZE=$((4*$MB)) SLICE_SIZE=$HPAGE_SIZE ;;
 elf_s390|elf64_s390)	HPAGE_SIZE=$((1*$MB)) SLICE_SIZE=$HPAGE_SIZE ;;
-armelf*_linux_eabi|aarch64elf*|aarch64linux*)
+armelf*_linux_eabi|aarch64elf*|aarch64linux*|elf64loongarch)
 	hpage_kb=$(cat /proc/meminfo  | grep Hugepagesize: | awk '{print $2}')
 	HPAGE_SIZE=$((hpage_kb * 1024))
 	SLICE_SIZE=$HPAGE_SIZE ;;
@@ -130,7 +130,7 @@ if [ "$HTLB_ALIGN" == "slice" ]; then
 	# targeting the ARM platform one needs to explicitly set the text segment offset
 	# otherwise it will be NULL.
 	case "$EMU" in
-	armelf*_linux_eabi|aarch64elf*|aarch64linux*)
+	armelf*_linux_eabi|aarch64elf*|aarch64linux*|elf64loongarch)
 		printf -v TEXTADDR "%x" "$SLICE_SIZE"
 		HTLBOPTS="$HTLBOPTS -Ttext-segment=$TEXTADDR" ;;
 	elf_i386)		HTLBOPTS="$HTLBOPTS -Ttext-segment=0x08000000" ;;
diff --git a/sys-elf64-loongarch.S b/sys-elf64-loongarch.S
new file mode 100644
index 0000000..24c5f05
--- /dev/null
+++ b/sys-elf64-loongarch.S
@@ -0,0 +1,24 @@
+/*
+ * libhugetlbfs - direct system call for loongarch64
+ *
+ * Author(s): Zhang Wenlong
+ */
+
+
+	.text
+
+	.globl	direct_syscall
+
+direct_syscall:
+	move	$a0,$ra
+	move	$a1,$a0
+	move	$a2,$a1
+	move	$a3,$a2
+	move	$a4,$a6
+	move	$a5,$a4
+	move	$fp,$a5
+	syscall	0
+	jr	$ra
+#if defined(__linux__) && defined(__ELF__)
+	.section .note.GNU-stack,"",%progbits
+#endif
diff --git a/tests/icache-hygiene.c b/tests/icache-hygiene.c
index 394d900..0013900 100644
--- a/tests/icache-hygiene.c
+++ b/tests/icache-hygiene.c
@@ -88,7 +88,7 @@ static void sig_handler(int signum, siginfo_t *si, void *uc)
 {
 #if defined(__powerpc__) || defined(__powerpc64__) || defined(__ia64__) || \
     defined(__s390__) || defined(__s390x__) || defined(__sparc__) || \
-    defined(__aarch64__) || (defined(__riscv) && __riscv_xlen == 64)
+    defined(__aarch64__) || (defined(__riscv) && __riscv_xlen == 64) || defined(__loongarch__)
 	/* On powerpc, ia64, s390 and Aarch64, 0 bytes are an illegal
 	 * instruction, so, if the icache is cleared properly, we SIGILL
 	 * as soon as we jump into the cleared page */