1 // SPDX-License-Identifier: GPL-2.0-or-later
11  * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
13  * This file handles the architecture-dependent parts of process handling...
50  * Used at user space -> kernel transitions.
63 	/* Whoops - the platform was unable to reboot. Tell the user! */  in machine_restart()
64 	pr_emerg("Reboot failed -- System halted\n");  in machine_restart()
69  * This is used if a sys-off handler was not set by a power management
80  * here to freeze the system for e.g. post-mortem debug purpose when
81  * possible.  This halt has nothing to do with the idle halt.
85 	printk(KERN_INFO "*** MACHINE HALT ***\n");  in machine_halt()
89 /* If or when software power-off is implemented, add code here.  */
121 void show_regs(struct pt_regs *regs)  in show_regs()  argument
125 	show_registers(regs);  in show_regs()
129  * Copy the thread-specific (arch specific) info from the current
168 	unsigned long clone_flags = args->flags;  in copy_thread()
169 	unsigned long usp = args->stack;  in copy_thread()
170 	unsigned long tls = args->tls;  in copy_thread()
179 	sp -= STACK_FRAME_OVERHEAD;	/* redzone */  in copy_thread()
180 	sp -= sizeof(struct pt_regs);  in copy_thread()
184 	sp -= STACK_FRAME_OVERHEAD;	/* redzone */  in copy_thread()
185 	sp -= sizeof(struct pt_regs);  in copy_thread()
188 	if (unlikely(args->fn)) {  in copy_thread()
190 		kregs->gpr[20] = (unsigned long)args->fn;  in copy_thread()
191 		kregs->gpr[22] = (unsigned long)args->fn_arg;  in copy_thread()
196 			userregs->sp = usp;  in copy_thread()
202 			userregs->gpr[10] = tls;  in copy_thread()
204 		userregs->gpr[11] = 0;	/* Result from fork() */  in copy_thread()
206 		kregs->gpr[20] = 0;	/* Userspace thread */  in copy_thread()
210 	 * _switch wants the kernel stack page in pt_regs->sp so that it  in copy_thread()
211 	 * can restore it to thread_info->ksp... see _switch for details.  in copy_thread()
213 	kregs->sp = top_of_kernel_stack;  in copy_thread()
214 	kregs->gpr[9] = (unsigned long)ret_from_fork;  in copy_thread()
216 	task_thread_info(p)->ksp = (unsigned long)kregs;  in copy_thread()
224 void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long sp)  in start_thread()  argument
228 	memset(regs, 0, sizeof(struct pt_regs));  in start_thread()
230 	regs->pc = pc;  in start_thread()
231 	regs->sr = sr;  in start_thread()
232 	regs->sp = sp;  in start_thread()
251 	 * (one for each cpu). we need them at user->kernel transition,  in __switch_to()
252 	 * while we save them at kernel->user transition  in __switch_to()
254 	new_ti = new->stack;  in __switch_to()
255 	old_ti = old->stack;  in __switch_to()
260 	last = (_switch(old_ti, new_ti))->task;  in __switch_to()
273 void dump_elf_thread(elf_greg_t *dest, struct pt_regs* regs)  in dump_elf_thread()  argument
276 	memcpy(dest+1, regs->gpr+1, 31*sizeof(unsigned long));  in dump_elf_thread()
277 	dest[32] = regs->pc;  in dump_elf_thread()
278 	dest[33] = regs->sr;  in dump_elf_thread()