1 files changed, 95 insertions, 0 deletions
diff --git a/arch/loongarch/kernel/genex.S b/arch/loongarch/kernel/genex.S
new file mode 100644
index 000000000000..75e5be807a0d
--- /dev/null
+++ b/arch/loongarch/kernel/genex.S
@@ -0,0 +1,95 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
+ *
+ * Derived from MIPS:
+ * Copyright (C) 1994 - 2000, 2001, 2003 Ralf Baechle
+ * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
+ * Copyright (C) 2002, 2007  Maciej W. Rozycki
+ * Copyright (C) 2001, 2012 MIPS Technologies, Inc.  All rights reserved.
+ */
+#include <asm/asm.h>
+#include <asm/asmmacro.h>
+#include <asm/loongarch.h>
+#include <asm/regdef.h>
+#include <asm/fpregdef.h>
+#include <asm/stackframe.h>
+#include <asm/thread_info.h>
+
+	.align	5
+SYM_FUNC_START(__arch_cpu_idle)
+	/* start of rollback region */
+	LONG_L	t0, tp, TI_FLAGS
+	nop
+	andi	t0, t0, _TIF_NEED_RESCHED
+	bnez	t0, 1f
+	nop
+	nop
+	nop
+	idle	0
+	/* end of rollback region */
+1:	jr	ra
+SYM_FUNC_END(__arch_cpu_idle)
+
+SYM_FUNC_START(handle_vint)
+	BACKUP_T0T1
+	SAVE_ALL
+	la.abs	t1, __arch_cpu_idle
+	LONG_L	t0, sp, PT_ERA
+	/* 32 byte rollback region */
+	ori	t0, t0, 0x1f
+	xori	t0, t0, 0x1f
+	bne	t0, t1, 1f
+	LONG_S	t0, sp, PT_ERA
+1:	move	a0, sp
+	move	a1, sp
+	la.abs	t0, do_vint
+	jirl	ra, t0, 0
+	RESTORE_ALL_AND_RET
+SYM_FUNC_END(handle_vint)
+
+SYM_FUNC_START(except_vec_cex)
+	b	cache_parity_error
+SYM_FUNC_END(except_vec_cex)
+
+	.macro	build_prep_badv
+	csrrd	t0, LOONGARCH_CSR_BADV
+	PTR_S	t0, sp, PT_BVADDR
+	.endm
+
+	.macro	build_prep_fcsr
+	movfcsr2gr	a1, fcsr0
+	.endm
+
+	.macro	build_prep_none
+	.endm
+
+	.macro	BUILD_HANDLER exception handler prep
+	.align	5
+	SYM_FUNC_START(handle_\exception)
+	BACKUP_T0T1
+	SAVE_ALL
+	build_prep_\prep
+	move	a0, sp
+	la.abs	t0, do_\handler
+	jirl	ra, t0, 0
+	RESTORE_ALL_AND_RET
+	SYM_FUNC_END(handle_\exception)
+	.endm
+
+	BUILD_HANDLER ade ade badv
+	BUILD_HANDLER ale ale badv
+	BUILD_HANDLER bp bp none
+	BUILD_HANDLER fpe fpe fcsr
+	BUILD_HANDLER fpu fpu none
+	BUILD_HANDLER lsx lsx none
+	BUILD_HANDLER lasx lasx none
+	BUILD_HANDLER lbt lbt none
+	BUILD_HANDLER ri ri none
+	BUILD_HANDLER watch watch none
+	BUILD_HANDLER reserved reserved none	/* others */
+
+SYM_FUNC_START(handle_sys)
+	la.abs	t0, handle_syscall
+	jr	t0
+SYM_FUNC_END(handle_sys)