v4.19.13 snapshot.
diff --git a/arch/nds32/kernel/process.c b/arch/nds32/kernel/process.c
new file mode 100644
index 0000000..65fda98
--- /dev/null
+++ b/arch/nds32/kernel/process.c
@@ -0,0 +1,208 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2005-2017 Andes Technology Corporation
+
+#include <linux/sched.h>
+#include <linux/sched/debug.h>
+#include <linux/sched/task_stack.h>
+#include <linux/delay.h>
+#include <linux/kallsyms.h>
+#include <linux/uaccess.h>
+#include <asm/elf.h>
+#include <asm/proc-fns.h>
+#include <linux/ptrace.h>
+#include <linux/reboot.h>
+
+extern void setup_mm_for_reboot(char mode);
+#ifdef CONFIG_PROC_FS
+struct proc_dir_entry *proc_dir_cpu;
+EXPORT_SYMBOL(proc_dir_cpu);
+#endif
+
+extern inline void arch_reset(char mode)
+{
+ if (mode == 's') {
+ /* Use cpu handler, jump to 0 */
+ cpu_reset(0);
+ }
+}
+
+void (*pm_power_off) (void);
+EXPORT_SYMBOL(pm_power_off);
+
+static char reboot_mode_nds32 = 'h';
+
+int __init reboot_setup(char *str)
+{
+ reboot_mode_nds32 = str[0];
+ return 1;
+}
+
+static int cpub_pwroff(void)
+{
+ return 0;
+}
+
+__setup("reboot=", reboot_setup);
+
+void machine_halt(void)
+{
+ cpub_pwroff();
+}
+
+EXPORT_SYMBOL(machine_halt);
+
+void machine_power_off(void)
+{
+ if (pm_power_off)
+ pm_power_off();
+}
+
+EXPORT_SYMBOL(machine_power_off);
+
+void machine_restart(char *cmd)
+{
+ /*
+ * Clean and disable cache, and turn off interrupts
+ */
+ cpu_proc_fin();
+
+ /*
+ * Tell the mm system that we are going to reboot -
+ * we may need it to insert some 1:1 mappings so that
+ * soft boot works.
+ */
+ setup_mm_for_reboot(reboot_mode_nds32);
+
+ /* Execute kernel restart handler call chain */
+ do_kernel_restart(cmd);
+
+ /*
+ * Now call the architecture specific reboot code.
+ */
+ arch_reset(reboot_mode_nds32);
+
+ /*
+ * Whoops - the architecture was unable to reboot.
+ * Tell the user!
+ */
+ mdelay(1000);
+ pr_info("Reboot failed -- System halted\n");
+ while (1) ;
+}
+
+EXPORT_SYMBOL(machine_restart);
+
+void show_regs(struct pt_regs *regs)
+{
+ printk("PC is at %pS\n", (void *)instruction_pointer(regs));
+ printk("LP is at %pS\n", (void *)regs->lp);
+ pr_info("pc : [<%08lx>] lp : [<%08lx>] %s\n"
+ "sp : %08lx fp : %08lx gp : %08lx\n",
+ instruction_pointer(regs),
+ regs->lp, print_tainted(), regs->sp, regs->fp, regs->gp);
+ pr_info("r25: %08lx r24: %08lx\n", regs->uregs[25], regs->uregs[24]);
+
+ pr_info("r23: %08lx r22: %08lx r21: %08lx r20: %08lx\n",
+ regs->uregs[23], regs->uregs[22],
+ regs->uregs[21], regs->uregs[20]);
+ pr_info("r19: %08lx r18: %08lx r17: %08lx r16: %08lx\n",
+ regs->uregs[19], regs->uregs[18],
+ regs->uregs[17], regs->uregs[16]);
+ pr_info("r15: %08lx r14: %08lx r13: %08lx r12: %08lx\n",
+ regs->uregs[15], regs->uregs[14],
+ regs->uregs[13], regs->uregs[12]);
+ pr_info("r11: %08lx r10: %08lx r9 : %08lx r8 : %08lx\n",
+ regs->uregs[11], regs->uregs[10],
+ regs->uregs[9], regs->uregs[8]);
+ pr_info("r7 : %08lx r6 : %08lx r5 : %08lx r4 : %08lx\n",
+ regs->uregs[7], regs->uregs[6], regs->uregs[5], regs->uregs[4]);
+ pr_info("r3 : %08lx r2 : %08lx r1 : %08lx r0 : %08lx\n",
+ regs->uregs[3], regs->uregs[2], regs->uregs[1], regs->uregs[0]);
+ pr_info(" IRQs o%s Segment %s\n",
+ interrupts_enabled(regs) ? "n" : "ff",
+ segment_eq(get_fs(), get_ds())? "kernel" : "user");
+}
+
+EXPORT_SYMBOL(show_regs);
+
+void flush_thread(void)
+{
+}
+
+DEFINE_PER_CPU(struct task_struct *, __entry_task);
+
+asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");
+int copy_thread(unsigned long clone_flags, unsigned long stack_start,
+ unsigned long stk_sz, struct task_struct *p)
+{
+ struct pt_regs *childregs = task_pt_regs(p);
+
+ memset(&p->thread.cpu_context, 0, sizeof(struct cpu_context));
+
+ if (unlikely(p->flags & PF_KTHREAD)) {
+ memset(childregs, 0, sizeof(struct pt_regs));
+ /* kernel thread fn */
+ p->thread.cpu_context.r6 = stack_start;
+ /* kernel thread argument */
+ p->thread.cpu_context.r7 = stk_sz;
+ } else {
+ *childregs = *current_pt_regs();
+ if (stack_start)
+ childregs->sp = stack_start;
+ /* child get zero as ret. */
+ childregs->uregs[0] = 0;
+ childregs->osp = 0;
+ if (clone_flags & CLONE_SETTLS)
+ childregs->uregs[25] = childregs->uregs[3];
+ }
+ /* cpu context switching */
+ p->thread.cpu_context.pc = (unsigned long)ret_from_fork;
+ p->thread.cpu_context.sp = (unsigned long)childregs;
+
+#ifdef CONFIG_HWZOL
+ childregs->lb = 0;
+ childregs->le = 0;
+ childregs->lc = 0;
+#endif
+
+ return 0;
+}
+
+/*
+ * fill in the fpe structure for a core dump...
+ */
+int dump_fpu(struct pt_regs *regs, elf_fpregset_t * fpu)
+{
+ int fpvalid = 0;
+ return fpvalid;
+}
+
+EXPORT_SYMBOL(dump_fpu);
+
+unsigned long get_wchan(struct task_struct *p)
+{
+ unsigned long fp, lr;
+ unsigned long stack_start, stack_end;
+ int count = 0;
+
+ if (!p || p == current || p->state == TASK_RUNNING)
+ return 0;
+
+ if (IS_ENABLED(CONFIG_FRAME_POINTER)) {
+ stack_start = (unsigned long)end_of_stack(p);
+ stack_end = (unsigned long)task_stack_page(p) + THREAD_SIZE;
+
+ fp = thread_saved_fp(p);
+ do {
+ if (fp < stack_start || fp > stack_end)
+ return 0;
+ lr = ((unsigned long *)fp)[0];
+ if (!in_sched_functions(lr))
+ return lr;
+ fp = *(unsigned long *)(fp + 4);
+ } while (count++ < 16);
+ }
+ return 0;
+}
+
+EXPORT_SYMBOL(get_wchan);