summaryrefslogtreecommitdiffstats
path: root/arch/loongarch/lib/unaligned.S
diff options
context:
space:
mode:
Diffstat (limited to 'arch/loongarch/lib/unaligned.S')
-rw-r--r--arch/loongarch/lib/unaligned.S83
1 files changed, 83 insertions, 0 deletions
diff --git a/arch/loongarch/lib/unaligned.S b/arch/loongarch/lib/unaligned.S
new file mode 100644
index 0000000000..185f82d858
--- /dev/null
+++ b/arch/loongarch/lib/unaligned.S
@@ -0,0 +1,83 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
+ */
+
+#include <linux/linkage.h>
+
+#include <asm/asm.h>
+#include <asm/asmmacro.h>
+#include <asm/asm-extable.h>
+#include <asm/errno.h>
+#include <asm/regdef.h>
+
+.L_fixup_handle_unaligned:
+ li.w a0, -EFAULT
+ jr ra
+
+/*
+ * unsigned long unaligned_read(void *addr, void *value, unsigned long n, bool sign)
+ *
+ * a0: addr
+ * a1: value
+ * a2: n
+ * a3: sign
+ */
+SYM_FUNC_START(unaligned_read)
+ beqz a2, 5f
+
+ li.w t2, 0
+ addi.d t0, a2, -1
+ slli.d t1, t0, 3
+ add.d a0, a0, t0
+
+ beqz a3, 2f
+1: ld.b t3, a0, 0
+ b 3f
+
+2: ld.bu t3, a0, 0
+3: sll.d t3, t3, t1
+ or t2, t2, t3
+ addi.d t1, t1, -8
+ addi.d a0, a0, -1
+ addi.d a2, a2, -1
+ bgtz a2, 2b
+4: st.d t2, a1, 0
+
+ move a0, a2
+ jr ra
+
+5: li.w a0, -EFAULT
+ jr ra
+
+ _asm_extable 1b, .L_fixup_handle_unaligned
+ _asm_extable 2b, .L_fixup_handle_unaligned
+ _asm_extable 4b, .L_fixup_handle_unaligned
+SYM_FUNC_END(unaligned_read)
+
+/*
+ * unsigned long unaligned_write(void *addr, unsigned long value, unsigned long n)
+ *
+ * a0: addr
+ * a1: value
+ * a2: n
+ */
+SYM_FUNC_START(unaligned_write)
+ beqz a2, 3f
+
+ li.w t0, 0
+1: srl.d t1, a1, t0
+2: st.b t1, a0, 0
+ addi.d t0, t0, 8
+ addi.d a2, a2, -1
+ addi.d a0, a0, 1
+ bgtz a2, 1b
+
+ move a0, a2
+ jr ra
+
+3: li.w a0, -EFAULT
+ jr ra
+
+ _asm_extable 2b, .L_fixup_handle_unaligned
+SYM_FUNC_END(unaligned_write)