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-rw-r--r--arch/avr32/kernel/process.c450
1 files changed, 450 insertions, 0 deletions
diff --git a/arch/avr32/kernel/process.c b/arch/avr32/kernel/process.c
new file mode 100644
index 00000000000..ea339575032
--- /dev/null
+++ b/arch/avr32/kernel/process.c
@@ -0,0 +1,450 @@
+/*
+ * Copyright (C) 2004-2006 Atmel Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/sched.h>
+#include <linux/module.h>
+#include <linux/kallsyms.h>
+#include <linux/fs.h>
+#include <linux/pm.h>
+#include <linux/ptrace.h>
+#include <linux/slab.h>
+#include <linux/reboot.h>
+#include <linux/tick.h>
+#include <linux/uaccess.h>
+#include <linux/unistd.h>
+
+#include <asm/sysreg.h>
+#include <asm/ocd.h>
+#include <asm/syscalls.h>
+
+#include <mach/pm.h>
+
+void (*pm_power_off)(void);
+EXPORT_SYMBOL(pm_power_off);
+
+/*
+ * This file handles the architecture-dependent parts of process handling..
+ */
+
+void cpu_idle(void)
+{
+ /* endless idle loop with no priority at all */
+ while (1) {
+ tick_nohz_idle_enter();
+ rcu_idle_enter();
+ while (!need_resched())
+ cpu_idle_sleep();
+ rcu_idle_exit();
+ tick_nohz_idle_exit();
+ preempt_enable_no_resched();
+ schedule();
+ preempt_disable();
+ }
+}
+
+void machine_halt(void)
+{
+ /*
+ * Enter Stop mode. The 32 kHz oscillator will keep running so
+ * the RTC will keep the time properly and the system will
+ * boot quickly.
+ */
+ asm volatile("sleep 3\n\t"
+ "sub pc, -2");
+}
+
+void machine_power_off(void)
+{
+ if (pm_power_off)
+ pm_power_off();
+}
+
+void machine_restart(char *cmd)
+{
+ ocd_write(DC, (1 << OCD_DC_DBE_BIT));
+ ocd_write(DC, (1 << OCD_DC_RES_BIT));
+ while (1) ;
+}
+
+/*
+ * PC is actually discarded when returning from a system call -- the
+ * return address must be stored in LR. This function will make sure
+ * LR points to do_exit before starting the thread.
+ *
+ * Also, when returning from fork(), r12 is 0, so we must copy the
+ * argument as well.
+ *
+ * r0 : The argument to the main thread function
+ * r1 : The address of do_exit
+ * r2 : The address of the main thread function
+ */
+asmlinkage extern void kernel_thread_helper(void);
+__asm__(" .type kernel_thread_helper, @function\n"
+ "kernel_thread_helper:\n"
+ " mov r12, r0\n"
+ " mov lr, r2\n"
+ " mov pc, r1\n"
+ " .size kernel_thread_helper, . - kernel_thread_helper");
+
+int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags)
+{
+ struct pt_regs regs;
+
+ memset(&regs, 0, sizeof(regs));
+
+ regs.r0 = (unsigned long)arg;
+ regs.r1 = (unsigned long)fn;
+ regs.r2 = (unsigned long)do_exit;
+ regs.lr = (unsigned long)kernel_thread_helper;
+ regs.pc = (unsigned long)kernel_thread_helper;
+ regs.sr = MODE_SUPERVISOR;
+
+ return do_fork(flags | CLONE_VM | CLONE_UNTRACED,
+ 0, &regs, 0, NULL, NULL);
+}
+EXPORT_SYMBOL(kernel_thread);
+
+/*
+ * Free current thread data structures etc
+ */
+void exit_thread(void)
+{
+ ocd_disable(current);
+}
+
+void flush_thread(void)
+{
+ /* nothing to do */
+}
+
+void release_thread(struct task_struct *dead_task)
+{
+ /* do nothing */
+}
+
+static void dump_mem(const char *str, const char *log_lvl,
+ unsigned long bottom, unsigned long top)
+{
+ unsigned long p;
+ int i;
+
+ printk("%s%s(0x%08lx to 0x%08lx)\n", log_lvl, str, bottom, top);
+
+ for (p = bottom & ~31; p < top; ) {
+ printk("%s%04lx: ", log_lvl, p & 0xffff);
+
+ for (i = 0; i < 8; i++, p += 4) {
+ unsigned int val;
+
+ if (p < bottom || p >= top)
+ printk(" ");
+ else {
+ if (__get_user(val, (unsigned int __user *)p)) {
+ printk("\n");
+ goto out;
+ }
+ printk("%08x ", val);
+ }
+ }
+ printk("\n");
+ }
+
+out:
+ return;
+}
+
+static inline int valid_stack_ptr(struct thread_info *tinfo, unsigned long p)
+{
+ return (p > (unsigned long)tinfo)
+ && (p < (unsigned long)tinfo + THREAD_SIZE - 3);
+}
+
+#ifdef CONFIG_FRAME_POINTER
+static void show_trace_log_lvl(struct task_struct *tsk, unsigned long *sp,
+ struct pt_regs *regs, const char *log_lvl)
+{
+ unsigned long lr, fp;
+ struct thread_info *tinfo;
+
+ if (regs)
+ fp = regs->r7;
+ else if (tsk == current)
+ asm("mov %0, r7" : "=r"(fp));
+ else
+ fp = tsk->thread.cpu_context.r7;
+
+ /*
+ * Walk the stack as long as the frame pointer (a) is within
+ * the kernel stack of the task, and (b) it doesn't move
+ * downwards.
+ */
+ tinfo = task_thread_info(tsk);
+ printk("%sCall trace:\n", log_lvl);
+ while (valid_stack_ptr(tinfo, fp)) {
+ unsigned long new_fp;
+
+ lr = *(unsigned long *)fp;
+#ifdef CONFIG_KALLSYMS
+ printk("%s [<%08lx>] ", log_lvl, lr);
+#else
+ printk(" [<%08lx>] ", lr);
+#endif
+ print_symbol("%s\n", lr);
+
+ new_fp = *(unsigned long *)(fp + 4);
+ if (new_fp <= fp)
+ break;
+ fp = new_fp;
+ }
+ printk("\n");
+}
+#else
+static void show_trace_log_lvl(struct task_struct *tsk, unsigned long *sp,
+ struct pt_regs *regs, const char *log_lvl)
+{
+ unsigned long addr;
+
+ printk("%sCall trace:\n", log_lvl);
+
+ while (!kstack_end(sp)) {
+ addr = *sp++;
+ if (kernel_text_address(addr)) {
+#ifdef CONFIG_KALLSYMS
+ printk("%s [<%08lx>] ", log_lvl, addr);
+#else
+ printk(" [<%08lx>] ", addr);
+#endif
+ print_symbol("%s\n", addr);
+ }
+ }
+ printk("\n");
+}
+#endif
+
+void show_stack_log_lvl(struct task_struct *tsk, unsigned long sp,
+ struct pt_regs *regs, const char *log_lvl)
+{
+ struct thread_info *tinfo;
+
+ if (sp == 0) {
+ if (tsk)
+ sp = tsk->thread.cpu_context.ksp;
+ else
+ sp = (unsigned long)&tinfo;
+ }
+ if (!tsk)
+ tsk = current;
+
+ tinfo = task_thread_info(tsk);
+
+ if (valid_stack_ptr(tinfo, sp)) {
+ dump_mem("Stack: ", log_lvl, sp,
+ THREAD_SIZE + (unsigned long)tinfo);
+ show_trace_log_lvl(tsk, (unsigned long *)sp, regs, log_lvl);
+ }
+}
+
+void show_stack(struct task_struct *tsk, unsigned long *stack)
+{
+ show_stack_log_lvl(tsk, (unsigned long)stack, NULL, "");
+}
+
+void dump_stack(void)
+{
+ unsigned long stack;
+
+ show_trace_log_lvl(current, &stack, NULL, "");
+}
+EXPORT_SYMBOL(dump_stack);
+
+static const char *cpu_modes[] = {
+ "Application", "Supervisor", "Interrupt level 0", "Interrupt level 1",
+ "Interrupt level 2", "Interrupt level 3", "Exception", "NMI"
+};
+
+void show_regs_log_lvl(struct pt_regs *regs, const char *log_lvl)
+{
+ unsigned long sp = regs->sp;
+ unsigned long lr = regs->lr;
+ unsigned long mode = (regs->sr & MODE_MASK) >> MODE_SHIFT;
+
+ if (!user_mode(regs)) {
+ sp = (unsigned long)regs + FRAME_SIZE_FULL;
+
+ printk("%s", log_lvl);
+ print_symbol("PC is at %s\n", instruction_pointer(regs));
+ printk("%s", log_lvl);
+ print_symbol("LR is at %s\n", lr);
+ }
+
+ printk("%spc : [<%08lx>] lr : [<%08lx>] %s\n"
+ "%ssp : %08lx r12: %08lx r11: %08lx\n",
+ log_lvl, instruction_pointer(regs), lr, print_tainted(),
+ log_lvl, sp, regs->r12, regs->r11);
+ printk("%sr10: %08lx r9 : %08lx r8 : %08lx\n",
+ log_lvl, regs->r10, regs->r9, regs->r8);
+ printk("%sr7 : %08lx r6 : %08lx r5 : %08lx r4 : %08lx\n",
+ log_lvl, regs->r7, regs->r6, regs->r5, regs->r4);
+ printk("%sr3 : %08lx r2 : %08lx r1 : %08lx r0 : %08lx\n",
+ log_lvl, regs->r3, regs->r2, regs->r1, regs->r0);
+ printk("%sFlags: %c%c%c%c%c\n", log_lvl,
+ regs->sr & SR_Q ? 'Q' : 'q',
+ regs->sr & SR_V ? 'V' : 'v',
+ regs->sr & SR_N ? 'N' : 'n',
+ regs->sr & SR_Z ? 'Z' : 'z',
+ regs->sr & SR_C ? 'C' : 'c');
+ printk("%sMode bits: %c%c%c%c%c%c%c%c%c%c\n", log_lvl,
+ regs->sr & SR_H ? 'H' : 'h',
+ regs->sr & SR_J ? 'J' : 'j',
+ regs->sr & SR_DM ? 'M' : 'm',
+ regs->sr & SR_D ? 'D' : 'd',
+ regs->sr & SR_EM ? 'E' : 'e',
+ regs->sr & SR_I3M ? '3' : '.',
+ regs->sr & SR_I2M ? '2' : '.',
+ regs->sr & SR_I1M ? '1' : '.',
+ regs->sr & SR_I0M ? '0' : '.',
+ regs->sr & SR_GM ? 'G' : 'g');
+ printk("%sCPU Mode: %s\n", log_lvl, cpu_modes[mode]);
+ printk("%sProcess: %s [%d] (task: %p thread: %p)\n",
+ log_lvl, current->comm, current->pid, current,
+ task_thread_info(current));
+}
+
+void show_regs(struct pt_regs *regs)
+{
+ unsigned long sp = regs->sp;
+
+ if (!user_mode(regs))
+ sp = (unsigned long)regs + FRAME_SIZE_FULL;
+
+ show_regs_log_lvl(regs, "");
+ show_trace_log_lvl(current, (unsigned long *)sp, regs, "");
+}
+EXPORT_SYMBOL(show_regs);
+
+/* Fill in the fpu structure for a core dump. This is easy -- we don't have any */
+int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu)
+{
+ /* Not valid */
+ return 0;
+}
+
+asmlinkage void ret_from_fork(void);
+
+int copy_thread(unsigned long clone_flags, unsigned long usp,
+ unsigned long unused,
+ struct task_struct *p, struct pt_regs *regs)
+{
+ struct pt_regs *childregs;
+
+ childregs = ((struct pt_regs *)(THREAD_SIZE + (unsigned long)task_stack_page(p))) - 1;
+ *childregs = *regs;
+
+ if (user_mode(regs))
+ childregs->sp = usp;
+ else
+ childregs->sp = (unsigned long)task_stack_page(p) + THREAD_SIZE;
+
+ childregs->r12 = 0; /* Set return value for child */
+
+ p->thread.cpu_context.sr = MODE_SUPERVISOR | SR_GM;
+ p->thread.cpu_context.ksp = (unsigned long)childregs;
+ p->thread.cpu_context.pc = (unsigned long)ret_from_fork;
+
+ clear_tsk_thread_flag(p, TIF_DEBUG);
+ if ((clone_flags & CLONE_PTRACE) && test_thread_flag(TIF_DEBUG))
+ ocd_enable(p);
+
+ return 0;
+}
+
+/* r12-r8 are dummy parameters to force the compiler to use the stack */
+asmlinkage int sys_fork(struct pt_regs *regs)
+{
+ return do_fork(SIGCHLD, regs->sp, regs, 0, NULL, NULL);
+}
+
+asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
+ void __user *parent_tidptr, void __user *child_tidptr,
+ struct pt_regs *regs)
+{
+ if (!newsp)
+ newsp = regs->sp;
+ return do_fork(clone_flags, newsp, regs, 0, parent_tidptr,
+ child_tidptr);
+}
+
+asmlinkage int sys_vfork(struct pt_regs *regs)
+{
+ return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->sp, regs,
+ 0, NULL, NULL);
+}
+
+asmlinkage int sys_execve(const char __user *ufilename,
+ const char __user *const __user *uargv,
+ const char __user *const __user *uenvp,
+ struct pt_regs *regs)
+{
+ int error;
+ char *filename;
+
+ filename = getname(ufilename);
+ error = PTR_ERR(filename);
+ if (IS_ERR(filename))
+ goto out;
+
+ error = do_execve(filename, uargv, uenvp, regs);
+ putname(filename);
+
+out:
+ return error;
+}
+
+
+/*
+ * This function is supposed to answer the question "who called
+ * schedule()?"
+ */
+unsigned long get_wchan(struct task_struct *p)
+{
+ unsigned long pc;
+ unsigned long stack_page;
+
+ if (!p || p == current || p->state == TASK_RUNNING)
+ return 0;
+
+ stack_page = (unsigned long)task_stack_page(p);
+ BUG_ON(!stack_page);
+
+ /*
+ * The stored value of PC is either the address right after
+ * the call to __switch_to() or ret_from_fork.
+ */
+ pc = thread_saved_pc(p);
+ if (in_sched_functions(pc)) {
+#ifdef CONFIG_FRAME_POINTER
+ unsigned long fp = p->thread.cpu_context.r7;
+ BUG_ON(fp < stack_page || fp > (THREAD_SIZE + stack_page));
+ pc = *(unsigned long *)fp;
+#else
+ /*
+ * We depend on the frame size of schedule here, which
+ * is actually quite ugly. It might be possible to
+ * determine the frame size automatically at build
+ * time by doing this:
+ * - compile sched.c
+ * - disassemble the resulting sched.o
+ * - look for 'sub sp,??' shortly after '<schedule>:'
+ */
+ unsigned long sp = p->thread.cpu_context.ksp + 16;
+ BUG_ON(sp < stack_page || sp > (THREAD_SIZE + stack_page));
+ pc = *(unsigned long *)sp;
+#endif
+ }
+
+ return pc;
+}