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.ksp; 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 ksp for switch_to !!! */ 60 p->thread.ksp = (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 unsigned long get_wchan(struct task_struct *p) 102 { 103 unsigned long lr; 104 unsigned long *fp, *stack_start, *stack_end; 105 int count = 0; 106 107 if (!p || p == current || p->state == TASK_RUNNING) 108 return 0; 109 110 stack_start = (unsigned long *)end_of_stack(p); 111 stack_end = (unsigned long *)(task_stack_page(p) + THREAD_SIZE); 112 113 fp = (unsigned long *) thread_saved_fp(p); 114 do { 115 if (fp < stack_start || fp > stack_end) 116 return 0; 117 #ifdef CONFIG_STACKTRACE 118 lr = fp[1]; 119 fp = (unsigned long *)fp[0]; 120 #else 121 lr = *fp++; 122 #endif 123 if (!in_sched_functions(lr) && 124 __kernel_text_address(lr)) 125 return lr; 126 } while (count++ < 16); 127 128 return 0; 129 } 130 EXPORT_SYMBOL(get_wchan); 131 132 #ifndef CONFIG_CPU_PM_NONE 133 void arch_cpu_idle(void) 134 { 135 #ifdef CONFIG_CPU_PM_WAIT 136 asm volatile("wait\n"); 137 #endif 138 139 #ifdef CONFIG_CPU_PM_DOZE 140 asm volatile("doze\n"); 141 #endif 142 143 #ifdef CONFIG_CPU_PM_STOP 144 asm volatile("stop\n"); 145 #endif 146 local_irq_enable(); 147 } 148 #endif 149