1 // SPDX-License-Identifier: GPL-2.0 2 // Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd. 3 4 #include <linux/module.h> 5 #include <linux/version.h> 6 #include <linux/sched.h> 7 #include <linux/sched/task_stack.h> 8 #include <linux/sched/debug.h> 9 #include <linux/delay.h> 10 #include <linux/kallsyms.h> 11 #include <linux/uaccess.h> 12 #include <linux/ptrace.h> 13 14 #include <asm/elf.h> 15 #include <abi/reg_ops.h> 16 17 struct cpuinfo_csky cpu_data[NR_CPUS]; 18 19 #ifdef CONFIG_STACKPROTECTOR 20 #include <linux/stackprotector.h> 21 unsigned long __stack_chk_guard __read_mostly; 22 EXPORT_SYMBOL(__stack_chk_guard); 23 #endif 24 25 asmlinkage void ret_from_fork(void); 26 asmlinkage void ret_from_kernel_thread(void); 27 28 /* 29 * Some archs flush debug and FPU info here 30 */ 31 void flush_thread(void){} 32 33 /* 34 * Return saved PC from a blocked thread 35 */ 36 unsigned long thread_saved_pc(struct task_struct *tsk) 37 { 38 struct switch_stack *sw = (struct switch_stack *)tsk->thread.sp; 39 40 return sw->r15; 41 } 42 43 int copy_thread_tls(unsigned long clone_flags, 44 unsigned long usp, 45 unsigned long kthread_arg, 46 struct task_struct *p, 47 unsigned long tls) 48 { 49 struct switch_stack *childstack; 50 struct pt_regs *childregs = task_pt_regs(p); 51 52 #ifdef CONFIG_CPU_HAS_FPU 53 save_to_user_fp(&p->thread.user_fp); 54 #endif 55 56 childstack = ((struct switch_stack *) childregs) - 1; 57 memset(childstack, 0, sizeof(struct switch_stack)); 58 59 /* setup thread.sp for switch_to !!! */ 60 p->thread.sp = (unsigned long)childstack; 61 62 if (unlikely(p->flags & PF_KTHREAD)) { 63 memset(childregs, 0, sizeof(struct pt_regs)); 64 childstack->r15 = (unsigned long) ret_from_kernel_thread; 65 childstack->r10 = kthread_arg; 66 childstack->r9 = usp; 67 childregs->sr = mfcr("psr"); 68 } else { 69 *childregs = *(current_pt_regs()); 70 if (usp) 71 childregs->usp = usp; 72 if (clone_flags & CLONE_SETTLS) 73 task_thread_info(p)->tp_value = childregs->tls 74 = tls; 75 76 childregs->a0 = 0; 77 childstack->r15 = (unsigned long) ret_from_fork; 78 } 79 80 return 0; 81 } 82 83 /* Fill in the fpu structure for a core dump. */ 84 int dump_fpu(struct pt_regs *regs, struct user_fp *fpu) 85 { 86 memcpy(fpu, ¤t->thread.user_fp, sizeof(*fpu)); 87 return 1; 88 } 89 EXPORT_SYMBOL(dump_fpu); 90 91 int dump_task_regs(struct task_struct *tsk, elf_gregset_t *pr_regs) 92 { 93 struct pt_regs *regs = task_pt_regs(tsk); 94 95 /* NOTE: usp is error value. */ 96 ELF_CORE_COPY_REGS((*pr_regs), regs) 97 98 return 1; 99 } 100 101 #ifndef CONFIG_CPU_PM_NONE 102 void arch_cpu_idle(void) 103 { 104 #ifdef CONFIG_CPU_PM_WAIT 105 asm volatile("wait\n"); 106 #endif 107 108 #ifdef CONFIG_CPU_PM_DOZE 109 asm volatile("doze\n"); 110 #endif 111 112 #ifdef CONFIG_CPU_PM_STOP 113 asm volatile("stop\n"); 114 #endif 115 local_irq_enable(); 116 } 117 #endif 118