1/* 2 * Copyright (C) 2004-2006 Atmel Corporation 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License version 2 as 6 * published by the Free Software Foundation. 7 */ 8#include <linux/sched.h> 9#include <linux/module.h> 10#include <linux/kallsyms.h> 11#include <linux/fs.h> 12#include <linux/pm.h> 13#include <linux/ptrace.h> 14#include <linux/slab.h> 15#include <linux/reboot.h> 16#include <linux/tick.h> 17#include <linux/uaccess.h> 18#include <linux/unistd.h> 19 20#include <asm/sysreg.h> 21#include <asm/ocd.h> 22#include <asm/syscalls.h> 23 24#include <mach/pm.h> 25 26void (*pm_power_off)(void); 27EXPORT_SYMBOL(pm_power_off); 28 29/* 30 * This file handles the architecture-dependent parts of process handling.. 31 */ 32 33void arch_cpu_idle(void) 34{ 35 cpu_enter_idle(); 36} 37 38void machine_halt(void) 39{ 40 /* 41 * Enter Stop mode. The 32 kHz oscillator will keep running so 42 * the RTC will keep the time properly and the system will 43 * boot quickly. 44 */ 45 asm volatile("sleep 3\n\t" 46 "sub pc, -2"); 47} 48 49void machine_power_off(void) 50{ 51 if (pm_power_off) 52 pm_power_off(); 53} 54 55void machine_restart(char *cmd) 56{ 57 ocd_write(DC, (1 << OCD_DC_DBE_BIT)); 58 ocd_write(DC, (1 << OCD_DC_RES_BIT)); 59 while (1) ; 60} 61 62/* 63 * Free current thread data structures etc 64 */ 65void exit_thread(void) 66{ 67 ocd_disable(current); 68} 69 70void flush_thread(void) 71{ 72 /* nothing to do */ 73} 74 75void release_thread(struct task_struct *dead_task) 76{ 77 /* do nothing */ 78} 79 80static void dump_mem(const char *str, const char *log_lvl, 81 unsigned long bottom, unsigned long top) 82{ 83 unsigned long p; 84 int i; 85 86 printk("%s%s(0x%08lx to 0x%08lx)\n", log_lvl, str, bottom, top); 87 88 for (p = bottom & ~31; p < top; ) { 89 printk("%s%04lx: ", log_lvl, p & 0xffff); 90 91 for (i = 0; i < 8; i++, p += 4) { 92 unsigned int val; 93 94 if (p < bottom || p >= top) 95 printk(" "); 96 else { 97 if (__get_user(val, (unsigned int __user *)p)) { 98 printk("\n"); 99 goto out; 100 } 101 printk("%08x ", val); 102 } 103 } 104 printk("\n"); 105 } 106 107out: 108 return; 109} 110 111static inline int valid_stack_ptr(struct thread_info *tinfo, unsigned long p) 112{ 113 return (p > (unsigned long)tinfo) 114 && (p < (unsigned long)tinfo + THREAD_SIZE - 3); 115} 116 117#ifdef CONFIG_FRAME_POINTER 118static void show_trace_log_lvl(struct task_struct *tsk, unsigned long *sp, 119 struct pt_regs *regs, const char *log_lvl) 120{ 121 unsigned long lr, fp; 122 struct thread_info *tinfo; 123 124 if (regs) 125 fp = regs->r7; 126 else if (tsk == current) 127 asm("mov %0, r7" : "=r"(fp)); 128 else 129 fp = tsk->thread.cpu_context.r7; 130 131 /* 132 * Walk the stack as long as the frame pointer (a) is within 133 * the kernel stack of the task, and (b) it doesn't move 134 * downwards. 135 */ 136 tinfo = task_thread_info(tsk); 137 printk("%sCall trace:\n", log_lvl); 138 while (valid_stack_ptr(tinfo, fp)) { 139 unsigned long new_fp; 140 141 lr = *(unsigned long *)fp; 142#ifdef CONFIG_KALLSYMS 143 printk("%s [<%08lx>] ", log_lvl, lr); 144#else 145 printk(" [<%08lx>] ", lr); 146#endif 147 print_symbol("%s\n", lr); 148 149 new_fp = *(unsigned long *)(fp + 4); 150 if (new_fp <= fp) 151 break; 152 fp = new_fp; 153 } 154 printk("\n"); 155} 156#else 157static void show_trace_log_lvl(struct task_struct *tsk, unsigned long *sp, 158 struct pt_regs *regs, const char *log_lvl) 159{ 160 unsigned long addr; 161 162 printk("%sCall trace:\n", log_lvl); 163 164 while (!kstack_end(sp)) { 165 addr = *sp++; 166 if (kernel_text_address(addr)) { 167#ifdef CONFIG_KALLSYMS 168 printk("%s [<%08lx>] ", log_lvl, addr); 169#else 170 printk(" [<%08lx>] ", addr); 171#endif 172 print_symbol("%s\n", addr); 173 } 174 } 175 printk("\n"); 176} 177#endif 178 179void show_stack_log_lvl(struct task_struct *tsk, unsigned long sp, 180 struct pt_regs *regs, const char *log_lvl) 181{ 182 struct thread_info *tinfo; 183 184 if (sp == 0) { 185 if (tsk) 186 sp = tsk->thread.cpu_context.ksp; 187 else 188 sp = (unsigned long)&tinfo; 189 } 190 if (!tsk) 191 tsk = current; 192 193 tinfo = task_thread_info(tsk); 194 195 if (valid_stack_ptr(tinfo, sp)) { 196 dump_mem("Stack: ", log_lvl, sp, 197 THREAD_SIZE + (unsigned long)tinfo); 198 show_trace_log_lvl(tsk, (unsigned long *)sp, regs, log_lvl); 199 } 200} 201 202void show_stack(struct task_struct *tsk, unsigned long *stack) 203{ 204 show_stack_log_lvl(tsk, (unsigned long)stack, NULL, ""); 205} 206 207static const char *cpu_modes[] = { 208 "Application", "Supervisor", "Interrupt level 0", "Interrupt level 1", 209 "Interrupt level 2", "Interrupt level 3", "Exception", "NMI" 210}; 211 212void show_regs_log_lvl(struct pt_regs *regs, const char *log_lvl) 213{ 214 unsigned long sp = regs->sp; 215 unsigned long lr = regs->lr; 216 unsigned long mode = (regs->sr & MODE_MASK) >> MODE_SHIFT; 217 218 show_regs_print_info(log_lvl); 219 220 if (!user_mode(regs)) { 221 sp = (unsigned long)regs + FRAME_SIZE_FULL; 222 223 printk("%s", log_lvl); 224 print_symbol("PC is at %s\n", instruction_pointer(regs)); 225 printk("%s", log_lvl); 226 print_symbol("LR is at %s\n", lr); 227 } 228 229 printk("%spc : [<%08lx>] lr : [<%08lx>] %s\n" 230 "%ssp : %08lx r12: %08lx r11: %08lx\n", 231 log_lvl, instruction_pointer(regs), lr, print_tainted(), 232 log_lvl, sp, regs->r12, regs->r11); 233 printk("%sr10: %08lx r9 : %08lx r8 : %08lx\n", 234 log_lvl, regs->r10, regs->r9, regs->r8); 235 printk("%sr7 : %08lx r6 : %08lx r5 : %08lx r4 : %08lx\n", 236 log_lvl, regs->r7, regs->r6, regs->r5, regs->r4); 237 printk("%sr3 : %08lx r2 : %08lx r1 : %08lx r0 : %08lx\n", 238 log_lvl, regs->r3, regs->r2, regs->r1, regs->r0); 239 printk("%sFlags: %c%c%c%c%c\n", log_lvl, 240 regs->sr & SR_Q ? 'Q' : 'q', 241 regs->sr & SR_V ? 'V' : 'v', 242 regs->sr & SR_N ? 'N' : 'n', 243 regs->sr & SR_Z ? 'Z' : 'z', 244 regs->sr & SR_C ? 'C' : 'c'); 245 printk("%sMode bits: %c%c%c%c%c%c%c%c%c%c\n", log_lvl, 246 regs->sr & SR_H ? 'H' : 'h', 247 regs->sr & SR_J ? 'J' : 'j', 248 regs->sr & SR_DM ? 'M' : 'm', 249 regs->sr & SR_D ? 'D' : 'd', 250 regs->sr & SR_EM ? 'E' : 'e', 251 regs->sr & SR_I3M ? '3' : '.', 252 regs->sr & SR_I2M ? '2' : '.', 253 regs->sr & SR_I1M ? '1' : '.', 254 regs->sr & SR_I0M ? '0' : '.', 255 regs->sr & SR_GM ? 'G' : 'g'); 256 printk("%sCPU Mode: %s\n", log_lvl, cpu_modes[mode]); 257} 258 259void show_regs(struct pt_regs *regs) 260{ 261 unsigned long sp = regs->sp; 262 263 if (!user_mode(regs)) 264 sp = (unsigned long)regs + FRAME_SIZE_FULL; 265 266 show_regs_log_lvl(regs, ""); 267 show_trace_log_lvl(current, (unsigned long *)sp, regs, ""); 268} 269EXPORT_SYMBOL(show_regs); 270 271/* Fill in the fpu structure for a core dump. This is easy -- we don't have any */ 272int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu) 273{ 274 /* Not valid */ 275 return 0; 276} 277 278asmlinkage void ret_from_fork(void); 279asmlinkage void ret_from_kernel_thread(void); 280asmlinkage void syscall_return(void); 281 282int copy_thread(unsigned long clone_flags, unsigned long usp, 283 unsigned long arg, 284 struct task_struct *p) 285{ 286 struct pt_regs *childregs = task_pt_regs(p); 287 288 if (unlikely(p->flags & PF_KTHREAD)) { 289 memset(childregs, 0, sizeof(struct pt_regs)); 290 p->thread.cpu_context.r0 = arg; 291 p->thread.cpu_context.r1 = usp; /* fn */ 292 p->thread.cpu_context.r2 = (unsigned long)syscall_return; 293 p->thread.cpu_context.pc = (unsigned long)ret_from_kernel_thread; 294 childregs->sr = MODE_SUPERVISOR; 295 } else { 296 *childregs = *current_pt_regs(); 297 if (usp) 298 childregs->sp = usp; 299 childregs->r12 = 0; /* Set return value for child */ 300 p->thread.cpu_context.pc = (unsigned long)ret_from_fork; 301 } 302 303 p->thread.cpu_context.sr = MODE_SUPERVISOR | SR_GM; 304 p->thread.cpu_context.ksp = (unsigned long)childregs; 305 306 clear_tsk_thread_flag(p, TIF_DEBUG); 307 if ((clone_flags & CLONE_PTRACE) && test_thread_flag(TIF_DEBUG)) 308 ocd_enable(p); 309 310 return 0; 311} 312 313/* 314 * This function is supposed to answer the question "who called 315 * schedule()?" 316 */ 317unsigned long get_wchan(struct task_struct *p) 318{ 319 unsigned long pc; 320 unsigned long stack_page; 321 322 if (!p || p == current || p->state == TASK_RUNNING) 323 return 0; 324 325 stack_page = (unsigned long)task_stack_page(p); 326 BUG_ON(!stack_page); 327 328 /* 329 * The stored value of PC is either the address right after 330 * the call to __switch_to() or ret_from_fork. 331 */ 332 pc = thread_saved_pc(p); 333 if (in_sched_functions(pc)) { 334#ifdef CONFIG_FRAME_POINTER 335 unsigned long fp = p->thread.cpu_context.r7; 336 BUG_ON(fp < stack_page || fp > (THREAD_SIZE + stack_page)); 337 pc = *(unsigned long *)fp; 338#else 339 /* 340 * We depend on the frame size of schedule here, which 341 * is actually quite ugly. It might be possible to 342 * determine the frame size automatically at build 343 * time by doing this: 344 * - compile sched/core.c 345 * - disassemble the resulting sched.o 346 * - look for 'sub sp,??' shortly after '<schedule>:' 347 */ 348 unsigned long sp = p->thread.cpu_context.ksp + 16; 349 BUG_ON(sp < stack_page || sp > (THREAD_SIZE + stack_page)); 350 pc = *(unsigned long *)sp; 351#endif 352 } 353 354 return pc; 355} 356