Merge tag 'loongarch-5.20' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson

Pull LoongArch updates from Huacai Chen:

 - Optimise getcpu() with vDSO

 - PCI enablement on top of pci & irqchip changes

 - Stack unwinder and stack trace support

 - Some bug fixes and build error fixes

 - Update the default config file

* tag 'loongarch-5.20' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson:
  docs/zh_CN/LoongArch: Add I14 description
  docs/LoongArch: Add I14 description
  LoongArch: Update Loongson-3 default config file
  LoongArch: Add USER_STACKTRACE support
  LoongArch: Add STACKTRACE support
  LoongArch: Add prologue unwinder support
  LoongArch: Add guess unwinder support
  LoongArch: Add vDSO syscall __vdso_getcpu()
  LoongArch: Add PCI controller support
  LoongArch: Parse MADT to get multi-processor information
  LoongArch: Jump to the link address before enable PG
  LoongArch: Requires __force attributes for any casts
  LoongArch: Fix unsigned comparison with less than zero
  LoongArch: Adjust arch/loongarch/Kconfig
  LoongArch: cpuinfo: Fix a warning for CONFIG_CPUMASK_OFFSTACK

1 files changed, 42 insertions, 0 deletions

diff --git a/arch/loongarch/include/asm/unwind.h b/arch/loongarch/include/asm/unwind.h
new file mode 100644
index 000000000000..6af4718bdf01
--- /dev/null
+++ b/arch/loongarch/include/asm/unwind.h
@@ -0,0 +1,42 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Most of this ideas comes from x86.
+ *
+ * Copyright (C) 2022 Loongson Technology Corporation Limited
+ */
+#ifndef _ASM_UNWIND_H
+#define _ASM_UNWIND_H
+
+#include <linux/sched.h>
+
+#include <asm/stacktrace.h>
+
+enum unwinder_type {
+	UNWINDER_GUESS,
+	UNWINDER_PROLOGUE,
+};
+
+struct unwind_state {
+	char type; /* UNWINDER_XXX */
+	struct stack_info stack_info;
+	struct task_struct *task;
+	bool first, error;
+	unsigned long sp, pc, ra;
+};
+
+void unwind_start(struct unwind_state *state,
+		  struct task_struct *task, struct pt_regs *regs);
+bool unwind_next_frame(struct unwind_state *state);
+unsigned long unwind_get_return_address(struct unwind_state *state);
+
+static inline bool unwind_done(struct unwind_state *state)
+{
+	return state->stack_info.type == STACK_TYPE_UNKNOWN;
+}
+
+static inline bool unwind_error(struct unwind_state *state)
+{
+	return state->error;
+}
+
+#endif /* _ASM_UNWIND_H */