1/* 2 * linux/arch/m32r/kernel/process.c 3 * 4 * Copyright (c) 2001, 2002 Hiroyuki Kondo, Hirokazu Takata, 5 * Hitoshi Yamamoto 6 * Taken from sh version. 7 * Copyright (C) 1995 Linus Torvalds 8 * SuperH version: Copyright (C) 1999, 2000 Niibe Yutaka & Kaz Kojima 9 */ 10 11#undef DEBUG_PROCESS 12#ifdef DEBUG_PROCESS 13#define DPRINTK(fmt, args...) printk("%s:%d:%s: " fmt, __FILE__, __LINE__, \ 14 __FUNCTION__, ##args) 15#else 16#define DPRINTK(fmt, args...) 17#endif 18 19/* 20 * This file handles the architecture-dependent parts of process handling.. 21 */ 22 23#include <linux/fs.h> 24#include <linux/module.h> 25#include <linux/ptrace.h> 26#include <linux/unistd.h> 27#include <linux/slab.h> 28#include <linux/hardirq.h> 29 30#include <asm/io.h> 31#include <asm/uaccess.h> 32#include <asm/mmu_context.h> 33#include <asm/elf.h> 34#include <asm/m32r.h> 35 36#include <linux/err.h> 37 38static int hlt_counter=0; 39 40/* 41 * Return saved PC of a blocked thread. 42 */ 43unsigned long thread_saved_pc(struct task_struct *tsk) 44{ 45 return tsk->thread.lr; 46} 47 48/* 49 * Powermanagement idle function, if any.. 50 */ 51void (*pm_idle)(void) = NULL; 52EXPORT_SYMBOL(pm_idle); 53 54void (*pm_power_off)(void) = NULL; 55EXPORT_SYMBOL(pm_power_off); 56 57void disable_hlt(void) 58{ 59 hlt_counter++; 60} 61 62EXPORT_SYMBOL(disable_hlt); 63 64void enable_hlt(void) 65{ 66 hlt_counter--; 67} 68 69EXPORT_SYMBOL(enable_hlt); 70 71/* 72 * We use this is we don't have any better 73 * idle routine.. 74 */ 75void default_idle(void) 76{ 77 /* M32R_FIXME: Please use "cpu_sleep" mode. */ 78 cpu_relax(); 79} 80 81/* 82 * On SMP it's slightly faster (but much more power-consuming!) 83 * to poll the ->work.need_resched flag instead of waiting for the 84 * cross-CPU IPI to arrive. Use this option with caution. 85 */ 86static void poll_idle (void) 87{ 88 /* M32R_FIXME */ 89 cpu_relax(); 90} 91 92/* 93 * The idle thread. There's no useful work to be 94 * done, so just try to conserve power and have a 95 * low exit latency (ie sit in a loop waiting for 96 * somebody to say that they'd like to reschedule) 97 */ 98void cpu_idle (void) 99{ 100 /* endless idle loop with no priority at all */ 101 while (1) { 102 while (!need_resched()) { 103 void (*idle)(void) = pm_idle; 104 105 if (!idle) 106 idle = default_idle; 107 108 idle(); 109 } 110 preempt_enable_no_resched(); 111 schedule(); 112 preempt_disable(); 113 } 114} 115 116void machine_restart(char *__unused) 117{ 118#if defined(CONFIG_PLAT_MAPPI3) 119 outw(1, (unsigned long)PLD_REBOOT); 120#endif 121 122 printk("Please push reset button!\n"); 123 while (1) 124 cpu_relax(); 125} 126 127void machine_halt(void) 128{ 129 printk("Please push reset button!\n"); 130 while (1) 131 cpu_relax(); 132} 133 134void machine_power_off(void) 135{ 136 /* M32R_FIXME */ 137} 138 139static int __init idle_setup (char *str) 140{ 141 if (!strncmp(str, "poll", 4)) { 142 printk("using poll in idle threads.\n"); 143 pm_idle = poll_idle; 144 } else if (!strncmp(str, "sleep", 4)) { 145 printk("using sleep in idle threads.\n"); 146 pm_idle = default_idle; 147 } 148 149 return 1; 150} 151 152__setup("idle=", idle_setup); 153 154void show_regs(struct pt_regs * regs) 155{ 156 printk("\n"); 157 printk("BPC[%08lx]:PSW[%08lx]:LR [%08lx]:FP [%08lx]\n", \ 158 regs->bpc, regs->psw, regs->lr, regs->fp); 159 printk("BBPC[%08lx]:BBPSW[%08lx]:SPU[%08lx]:SPI[%08lx]\n", \ 160 regs->bbpc, regs->bbpsw, regs->spu, regs->spi); 161 printk("R0 [%08lx]:R1 [%08lx]:R2 [%08lx]:R3 [%08lx]\n", \ 162 regs->r0, regs->r1, regs->r2, regs->r3); 163 printk("R4 [%08lx]:R5 [%08lx]:R6 [%08lx]:R7 [%08lx]\n", \ 164 regs->r4, regs->r5, regs->r6, regs->r7); 165 printk("R8 [%08lx]:R9 [%08lx]:R10[%08lx]:R11[%08lx]\n", \ 166 regs->r8, regs->r9, regs->r10, regs->r11); 167 printk("R12[%08lx]\n", \ 168 regs->r12); 169 170#if defined(CONFIG_ISA_M32R2) && defined(CONFIG_ISA_DSP_LEVEL2) 171 printk("ACC0H[%08lx]:ACC0L[%08lx]\n", \ 172 regs->acc0h, regs->acc0l); 173 printk("ACC1H[%08lx]:ACC1L[%08lx]\n", \ 174 regs->acc1h, regs->acc1l); 175#elif defined(CONFIG_ISA_M32R2) || defined(CONFIG_ISA_M32R) 176 printk("ACCH[%08lx]:ACCL[%08lx]\n", \ 177 regs->acc0h, regs->acc0l); 178#else 179#error unknown isa configuration 180#endif 181} 182 183/* 184 * Create a kernel thread 185 */ 186 187/* 188 * This is the mechanism for creating a new kernel thread. 189 * 190 * NOTE! Only a kernel-only process(ie the swapper or direct descendants 191 * who haven't done an "execve()") should use this: it will work within 192 * a system call from a "real" process, but the process memory space will 193 * not be free'd until both the parent and the child have exited. 194 */ 195static void kernel_thread_helper(void *nouse, int (*fn)(void *), void *arg) 196{ 197 fn(arg); 198 do_exit(-1); 199} 200 201int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags) 202{ 203 struct pt_regs regs; 204 205 memset(®s, 0, sizeof (regs)); 206 regs.r1 = (unsigned long)fn; 207 regs.r2 = (unsigned long)arg; 208 209 regs.bpc = (unsigned long)kernel_thread_helper; 210 211 regs.psw = M32R_PSW_BIE; 212 213 /* Ok, create the new process. */ 214 return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0, ®s, 0, NULL, 215 NULL); 216} 217 218/* 219 * Free current thread data structures etc.. 220 */ 221void exit_thread(void) 222{ 223 /* Nothing to do. */ 224 DPRINTK("pid = %d\n", current->pid); 225} 226 227void flush_thread(void) 228{ 229 DPRINTK("pid = %d\n", current->pid); 230 memset(¤t->thread.debug_trap, 0, sizeof(struct debug_trap)); 231} 232 233void release_thread(struct task_struct *dead_task) 234{ 235 /* do nothing */ 236 DPRINTK("pid = %d\n", dead_task->pid); 237} 238 239/* Fill in the fpu structure for a core dump.. */ 240int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu) 241{ 242 return 0; /* Task didn't use the fpu at all. */ 243} 244 245int copy_thread(int nr, unsigned long clone_flags, unsigned long spu, 246 unsigned long unused, struct task_struct *tsk, struct pt_regs *regs) 247{ 248 struct pt_regs *childregs = task_pt_regs(tsk); 249 extern void ret_from_fork(void); 250 251 /* Copy registers */ 252 *childregs = *regs; 253 254 childregs->spu = spu; 255 childregs->r0 = 0; /* Child gets zero as return value */ 256 regs->r0 = tsk->pid; 257 tsk->thread.sp = (unsigned long)childregs; 258 tsk->thread.lr = (unsigned long)ret_from_fork; 259 260 return 0; 261} 262 263/* 264 * Capture the user space registers if the task is not running (in user space) 265 */ 266int dump_task_regs(struct task_struct *tsk, elf_gregset_t *regs) 267{ 268 /* M32R_FIXME */ 269 return 1; 270} 271 272asmlinkage int sys_fork(unsigned long r0, unsigned long r1, unsigned long r2, 273 unsigned long r3, unsigned long r4, unsigned long r5, unsigned long r6, 274 struct pt_regs regs) 275{ 276#ifdef CONFIG_MMU 277 return do_fork(SIGCHLD, regs.spu, ®s, 0, NULL, NULL); 278#else 279 return -EINVAL; 280#endif /* CONFIG_MMU */ 281} 282 283asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp, 284 unsigned long parent_tidptr, 285 unsigned long child_tidptr, 286 unsigned long r4, unsigned long r5, unsigned long r6, 287 struct pt_regs regs) 288{ 289 if (!newsp) 290 newsp = regs.spu; 291 292 return do_fork(clone_flags, newsp, ®s, 0, 293 (int __user *)parent_tidptr, (int __user *)child_tidptr); 294} 295 296/* 297 * This is trivial, and on the face of it looks like it 298 * could equally well be done in user mode. 299 * 300 * Not so, for quite unobvious reasons - register pressure. 301 * In user mode vfork() cannot have a stack frame, and if 302 * done by calling the "clone()" system call directly, you 303 * do not have enough call-clobbered registers to hold all 304 * the information you need. 305 */ 306asmlinkage int sys_vfork(unsigned long r0, unsigned long r1, unsigned long r2, 307 unsigned long r3, unsigned long r4, unsigned long r5, unsigned long r6, 308 struct pt_regs regs) 309{ 310 return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs.spu, ®s, 0, 311 NULL, NULL); 312} 313 314/* 315 * sys_execve() executes a new program. 316 */ 317asmlinkage int sys_execve(char __user *ufilename, char __user * __user *uargv, 318 char __user * __user *uenvp, 319 unsigned long r3, unsigned long r4, unsigned long r5, 320 unsigned long r6, struct pt_regs regs) 321{ 322 int error; 323 char *filename; 324 325 filename = getname(ufilename); 326 error = PTR_ERR(filename); 327 if (IS_ERR(filename)) 328 goto out; 329 330 error = do_execve(filename, uargv, uenvp, ®s); 331 if (error == 0) { 332 task_lock(current); 333 current->ptrace &= ~PT_DTRACE; 334 task_unlock(current); 335 } 336 putname(filename); 337out: 338 return error; 339} 340 341/* 342 * These bracket the sleeping functions.. 343 */ 344#define first_sched ((unsigned long) scheduling_functions_start_here) 345#define last_sched ((unsigned long) scheduling_functions_end_here) 346 347unsigned long get_wchan(struct task_struct *p) 348{ 349 /* M32R_FIXME */ 350 return (0); 351} 352