arch/nios2/kernel/process.c

   1 /*
   2  * Architecture-dependent parts of process handling.
   3  *
   4  * Copyright (C) 2013 Altera Corporation
   5  * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch>
   6  * Copyright (C) 2009 Wind River Systems Inc
   7  *   Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com
   8  * Copyright (C) 2004 Microtronix Datacom Ltd
   9  *
  10  * This file is subject to the terms and conditions of the GNU General Public
  11  * License.  See the file "COPYING" in the main directory of this archive
  12  * for more details.
  13  */
  14
  15 #include <linux/export.h>
  16 #include <linux/sched.h>
  17 #include <linux/sched/debug.h>
  18 #include <linux/sched/task.h>
  19 #include <linux/tick.h>
  20 #include <linux/uaccess.h>
  21
  22 #include <asm/unistd.h>
  23 #include <asm/traps.h>
  24 #include <asm/cpuinfo.h>
  25
  26 asmlinkage void ret_from_fork(void);
  27 asmlinkage void ret_from_kernel_thread(void);
  28
  29 void (*pm_power_off)(void) = NULL;
  30 EXPORT_SYMBOL(pm_power_off);
  31
  32 void arch_cpu_idle(void)
  33 {
  34         local_irq_enable();
  35 }
  36
  37 /*
  38  * The development boards have no way to pull a board reset. Just jump to the
  39  * cpu reset address and let the boot loader or the code in head.S take care of
  40  * resetting peripherals.
  41  */
  42 void machine_restart(char *__unused)
  43 {
  44         pr_notice("Machine restart (%08x)...\n", cpuinfo.reset_addr);
  45         local_irq_disable();
  46         __asm__ __volatile__ (
  47         "jmp    %0\n\t"
  48         :
  49         : "r" (cpuinfo.reset_addr)
  50         : "r4");
  51 }
  52
  53 void machine_halt(void)
  54 {
  55         pr_notice("Machine halt...\n");
  56         local_irq_disable();
  57         for (;;)
  58                 ;
  59 }
  60
  61 /*
  62  * There is no way to power off the development boards. So just spin for now. If
  63  * we ever have a way of resetting a board using a GPIO we should add that here.
  64  */
  65 void machine_power_off(void)
  66 {
  67         pr_notice("Machine power off...\n");
  68         local_irq_disable();
  69         for (;;)
  70                 ;
  71 }
  72
  73 void show_regs(struct pt_regs *regs)
  74 {
  75         pr_notice("\n");
  76         show_regs_print_info(KERN_DEFAULT);
  77
  78         pr_notice("r1: %08lx r2: %08lx r3: %08lx r4: %08lx\n",
  79                 regs->r1,  regs->r2,  regs->r3,  regs->r4);
  80
  81         pr_notice("r5: %08lx r6: %08lx r7: %08lx r8: %08lx\n",
  82                 regs->r5,  regs->r6,  regs->r7,  regs->r8);
  83
  84         pr_notice("r9: %08lx r10: %08lx r11: %08lx r12: %08lx\n",
  85                 regs->r9,  regs->r10, regs->r11, regs->r12);
  86
  87         pr_notice("r13: %08lx r14: %08lx r15: %08lx\n",
  88                 regs->r13, regs->r14, regs->r15);
  89
  90         pr_notice("ra: %08lx fp:  %08lx sp: %08lx gp: %08lx\n",
  91                 regs->ra,  regs->fp,  regs->sp,  regs->gp);
  92
  93         pr_notice("ea: %08lx estatus: %08lx\n",
  94                 regs->ea,  regs->estatus);
  95 }
  96
  97 void flush_thread(void)
  98 {
  99 }
 100
 101 int copy_thread(unsigned long clone_flags,
 102                 unsigned long usp, unsigned long arg, struct task_struct *p)
 103 {
 104         struct pt_regs *childregs = task_pt_regs(p);
 105         struct pt_regs *regs;
 106         struct switch_stack *stack;
 107         struct switch_stack *childstack =
 108                 ((struct switch_stack *)childregs) - 1;
 109
 110         if (unlikely(p->flags & PF_KTHREAD)) {
 111                 memset(childstack, 0,
 112                         sizeof(struct switch_stack) + sizeof(struct pt_regs));
 113
 114                 childstack->r16 = usp;          /* fn */
 115                 childstack->r17 = arg;
 116                 childstack->ra = (unsigned long) ret_from_kernel_thread;
 117                 childregs->estatus = STATUS_PIE;
 118                 childregs->sp = (unsigned long) childstack;
 119
 120                 p->thread.ksp = (unsigned long) childstack;
 121                 p->thread.kregs = childregs;
 122                 return 0;
 123         }
 124
 125         regs = current_pt_regs();
 126         *childregs = *regs;
 127         childregs->r2 = 0;      /* Set the return value for the child. */
 128         childregs->r7 = 0;
 129
 130         stack = ((struct switch_stack *) regs) - 1;
 131         *childstack = *stack;
 132         childstack->ra = (unsigned long)ret_from_fork;
 133         p->thread.kregs = childregs;
 134         p->thread.ksp = (unsigned long) childstack;
 135
 136         if (usp)
 137                 childregs->sp = usp;
 138
 139         /* Initialize tls register. */
 140         if (clone_flags & CLONE_SETTLS)
 141                 childstack->r23 = regs->r8;
 142
 143         return 0;
 144 }
 145
 146 /*
 147  *      Generic dumping code. Used for panic and debug.
 148  */
 149 void dump(struct pt_regs *fp)
 150 {
 151         unsigned long   *sp;
 152         unsigned char   *tp;
 153         int             i;
 154
 155         pr_emerg("\nCURRENT PROCESS:\n\n");
 156         pr_emerg("COMM=%s PID=%d\n", current->comm, current->pid);
 157
 158         if (current->mm) {
 159                 pr_emerg("TEXT=%08x-%08x DATA=%08x-%08x BSS=%08x-%08x\n",
 160                         (int) current->mm->start_code,
 161                         (int) current->mm->end_code,
 162                         (int) current->mm->start_data,
 163                         (int) current->mm->end_data,
 164                         (int) current->mm->end_data,
 165                         (int) current->mm->brk);
 166                 pr_emerg("USER-STACK=%08x  KERNEL-STACK=%08x\n\n",
 167                         (int) current->mm->start_stack,
 168                         (int)(((unsigned long) current) + THREAD_SIZE));
 169         }
 170
 171         pr_emerg("PC: %08lx\n", fp->ea);
 172         pr_emerg("SR: %08lx    SP: %08lx\n",
 173                 (long) fp->estatus, (long) fp);
 174
 175         pr_emerg("r1: %08lx    r2: %08lx    r3: %08lx\n",
 176                 fp->r1, fp->r2, fp->r3);
 177
 178         pr_emerg("r4: %08lx    r5: %08lx    r6: %08lx    r7: %08lx\n",
 179                 fp->r4, fp->r5, fp->r6, fp->r7);
 180         pr_emerg("r8: %08lx    r9: %08lx    r10: %08lx    r11: %08lx\n",
 181                 fp->r8, fp->r9, fp->r10, fp->r11);
 182         pr_emerg("r12: %08lx  r13: %08lx    r14: %08lx    r15: %08lx\n",
 183                 fp->r12, fp->r13, fp->r14, fp->r15);
 184         pr_emerg("or2: %08lx   ra: %08lx     fp: %08lx    sp: %08lx\n",
 185                 fp->orig_r2, fp->ra, fp->fp, fp->sp);
 186         pr_emerg("\nUSP: %08x   TRAPFRAME: %08x\n",
 187                 (unsigned int) fp->sp, (unsigned int) fp);
 188
 189         pr_emerg("\nCODE:");
 190         tp = ((unsigned char *) fp->ea) - 0x20;
 191         for (sp = (unsigned long *) tp, i = 0; (i < 0x40);  i += 4) {
 192                 if ((i % 0x10) == 0)
 193                         pr_emerg("\n%08x: ", (int) (tp + i));
 194                 pr_emerg("%08x ", (int) *sp++);
 195         }
 196         pr_emerg("\n");
 197
 198         pr_emerg("\nKERNEL STACK:");
 199         tp = ((unsigned char *) fp) - 0x40;
 200         for (sp = (unsigned long *) tp, i = 0; (i < 0xc0); i += 4) {
 201                 if ((i % 0x10) == 0)
 202                         pr_emerg("\n%08x: ", (int) (tp + i));
 203                 pr_emerg("%08x ", (int) *sp++);
 204         }
 205         pr_emerg("\n");
 206         pr_emerg("\n");
 207
 208         pr_emerg("\nUSER STACK:");
 209         tp = (unsigned char *) (fp->sp - 0x10);
 210         for (sp = (unsigned long *) tp, i = 0; (i < 0x80); i += 4) {
 211                 if ((i % 0x10) == 0)
 212                         pr_emerg("\n%08x: ", (int) (tp + i));
 213                 pr_emerg("%08x ", (int) *sp++);
 214         }
 215         pr_emerg("\n\n");
 216 }
 217
 218 unsigned long get_wchan(struct task_struct *p)
 219 {
 220         unsigned long fp, pc;
 221         unsigned long stack_page;
 222         int count = 0;
 223
 224         if (!p || p == current || p->state == TASK_RUNNING)
 225                 return 0;
 226
 227         stack_page = (unsigned long)p;
 228         fp = ((struct switch_stack *)p->thread.ksp)->fp;        /* ;dgt2 */
 229         do {
 230                 if (fp < stack_page+sizeof(struct task_struct) ||
 231                         fp >= 8184+stack_page)  /* ;dgt2;tmp */
 232                         return 0;
 233                 pc = ((unsigned long *)fp)[1];
 234                 if (!in_sched_functions(pc))
 235                         return pc;
 236                 fp = *(unsigned long *) fp;
 237         } while (count++ < 16);         /* ;dgt2;tmp */
 238         return 0;
 239 }
 240
 241 /*
 242  * Do necessary setup to start up a newly executed thread.
 243  * Will startup in user mode (status_extension = 0).
 244  */
 245 void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long sp)
 246 {
 247         memset((void *) regs, 0, sizeof(struct pt_regs));
 248         regs->estatus = ESTATUS_EPIE | ESTATUS_EU;
 249         regs->ea = pc;
 250         regs->sp = sp;
 251 }
 252
 253 #include <linux/elfcore.h>
 254
 255 /* Fill in the FPU structure for a core dump. */
 256 int dump_fpu(struct pt_regs *regs, elf_fpregset_t *r)
 257 {
 258         return 0; /* Nios2 has no FPU and thus no FPU registers */
 259 }