diff options
Diffstat (limited to 'arch/nds32/kernel/process.c')
| -rw-r--r-- | arch/nds32/kernel/process.c | 262 |
1 files changed, 262 insertions, 0 deletions
diff --git a/arch/nds32/kernel/process.c b/arch/nds32/kernel/process.c new file mode 100644 index 000000000..c1327e552 --- /dev/null +++ b/arch/nds32/kernel/process.c @@ -0,0 +1,262 @@ +// 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 <asm/fpu.h> +#include <linux/ptrace.h> +#include <linux/reboot.h> + +#if IS_ENABLED(CONFIG_LAZY_FPU) +struct task_struct *last_task_used_math; +#endif + +extern void setup_mm_for_reboot(char mode); + +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", + uaccess_kernel() ? "kernel" : "user"); +} + +EXPORT_SYMBOL(show_regs); + +void exit_thread(struct task_struct *tsk) +{ +#if defined(CONFIG_FPU) && defined(CONFIG_LAZY_FPU) + if (last_task_used_math == tsk) + last_task_used_math = NULL; +#endif +} + +void flush_thread(void) +{ +#if defined(CONFIG_FPU) + clear_fpu(task_pt_regs(current)); + clear_used_math(); +# ifdef CONFIG_LAZY_FPU + if (last_task_used_math == current) + last_task_used_math = NULL; +# endif +#endif +} + +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, unsigned long tls) +{ + struct pt_regs *childregs = task_pt_regs(p); + + memset(&p->thread.cpu_context, 0, sizeof(struct cpu_context)); + + if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) { + 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] = tls; + } + /* cpu context switching */ + p->thread.cpu_context.pc = (unsigned long)ret_from_fork; + p->thread.cpu_context.sp = (unsigned long)childregs; + +#if IS_ENABLED(CONFIG_FPU) + if (used_math()) { +# if !IS_ENABLED(CONFIG_LAZY_FPU) + unlazy_fpu(current); +# else + preempt_disable(); + if (last_task_used_math == current) + save_fpu(current); + preempt_enable(); +# endif + p->thread.fpu = current->thread.fpu; + clear_fpu(task_pt_regs(p)); + set_stopped_child_used_math(p); + } +#endif + +#ifdef CONFIG_HWZOL + childregs->lb = 0; + childregs->le = 0; + childregs->lc = 0; +#endif + + return 0; +} + +#if IS_ENABLED(CONFIG_FPU) +struct task_struct *_switch_fpu(struct task_struct *prev, struct task_struct *next) +{ +#if !IS_ENABLED(CONFIG_LAZY_FPU) + unlazy_fpu(prev); +#endif + if (!(next->flags & PF_KTHREAD)) + clear_fpu(task_pt_regs(next)); + return prev; +} +#endif + +/* + * fill in the fpe structure for a core dump... + */ +int dump_fpu(struct pt_regs *regs, elf_fpregset_t * fpu) +{ + int fpvalid = 0; +#if IS_ENABLED(CONFIG_FPU) + struct task_struct *tsk = current; + + fpvalid = tsk_used_math(tsk); + if (fpvalid) { + lose_fpu(); + memcpy(fpu, &tsk->thread.fpu, sizeof(*fpu)); + } +#endif + 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); |