1 files changed, 97 insertions, 0 deletions
diff --git a/arch/loongarch/include/asm/kgdb.h b/arch/loongarch/include/asm/kgdb.h
new file mode 100644
index 000000000000..2041ae58b161
--- /dev/null
+++ b/arch/loongarch/include/asm/kgdb.h
@@ -0,0 +1,97 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2023 Loongson Technology Corporation Limited
+ */
+
+#ifndef _ASM_LOONGARCH_KGDB_H
+#define _ASM_LOONGARCH_KGDB_H
+
+#define GDB_SIZEOF_REG		sizeof(u64)
+
+/* gdb remote procotol expects the following register layout. */
+
+/*
+ * General purpose registers:
+ *     r0-r31: 64 bit
+ *     orig_a0: 64 bit
+ *     pc : 64 bit
+ *     csr_badvaddr: 64 bit
+ */
+#define DBG_PT_REGS_BASE	0
+#define DBG_PT_REGS_NUM		35
+#define DBG_PT_REGS_END		(DBG_PT_REGS_BASE + DBG_PT_REGS_NUM - 1)
+
+/*
+ * Floating point registers:
+ *     f0-f31: 64 bit
+ */
+#define DBG_FPR_BASE		(DBG_PT_REGS_END + 1)
+#define DBG_FPR_NUM		32
+#define DBG_FPR_END		(DBG_FPR_BASE + DBG_FPR_NUM - 1)
+
+/*
+ * Condition Flag registers:
+ *     fcc0-fcc8: 8 bit
+ */
+#define DBG_FCC_BASE		(DBG_FPR_END + 1)
+#define DBG_FCC_NUM		8
+#define DBG_FCC_END		(DBG_FCC_BASE + DBG_FCC_NUM - 1)
+
+/*
+ * Floating-point Control and Status registers:
+ *     fcsr: 32 bit
+ */
+#define DBG_FCSR_NUM		1
+#define DBG_FCSR		(DBG_FCC_END + 1)
+
+#define DBG_MAX_REG_NUM		(DBG_FCSR + 1)
+
+/*
+ * Size of I/O buffer for gdb packet.
+ * considering to hold all register contents, size is set
+ */
+#define BUFMAX			2048
+
+/*
+ * Number of bytes required for gdb_regs buffer.
+ * PT_REGS and FPR: 8 bytes; FCSR: 4 bytes; FCC: 1 bytes.
+ * GDB fails to connect for size beyond this with error
+ * "'g' packet reply is too long"
+ */
+#define NUMREGBYTES		((DBG_PT_REGS_NUM + DBG_FPR_NUM) * GDB_SIZEOF_REG + DBG_FCC_NUM * 1 + DBG_FCSR_NUM * 4)
+
+#define BREAK_INSTR_SIZE	4
+#define CACHE_FLUSH_IS_SAFE	0
+
+/* Register numbers of various important registers. */
+enum dbg_loongarch_regnum {
+	DBG_LOONGARCH_ZERO = 0,
+	DBG_LOONGARCH_RA,
+	DBG_LOONGARCH_TP,
+	DBG_LOONGARCH_SP,
+	DBG_LOONGARCH_A0,
+	DBG_LOONGARCH_FP = 22,
+	DBG_LOONGARCH_S0,
+	DBG_LOONGARCH_S1,
+	DBG_LOONGARCH_S2,
+	DBG_LOONGARCH_S3,
+	DBG_LOONGARCH_S4,
+	DBG_LOONGARCH_S5,
+	DBG_LOONGARCH_S6,
+	DBG_LOONGARCH_S7,
+	DBG_LOONGARCH_S8,
+	DBG_LOONGARCH_ORIG_A0,
+	DBG_LOONGARCH_PC,
+	DBG_LOONGARCH_BADV
+};
+
+void kgdb_breakinst(void);
+void arch_kgdb_breakpoint(void);
+
+#ifdef CONFIG_KGDB
+bool kgdb_breakpoint_handler(struct pt_regs *regs);
+#else /* !CONFIG_KGDB */
+static inline bool kgdb_breakpoint_handler(struct pt_regs *regs) { return false; }
+#endif /* CONFIG_KGDB */
+
+#endif /* __ASM_KGDB_H_ */