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-rw-r--r--arch/arm/kernel/process.c460
1 files changed, 460 insertions, 0 deletions
diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c
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--- /dev/null
+++ b/arch/arm/kernel/process.c
@@ -0,0 +1,460 @@
+/*
+ * linux/arch/arm/kernel/process.c
+ *
+ * Copyright (C) 1996-2000 Russell King - Converted to ARM.
+ * Original Copyright (C) 1995 Linus Torvalds
+ *
+ * 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 <stdarg.h>
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/stddef.h>
+#include <linux/unistd.h>
+#include <linux/ptrace.h>
+#include <linux/slab.h>
+#include <linux/user.h>
+#include <linux/a.out.h>
+#include <linux/delay.h>
+#include <linux/reboot.h>
+#include <linux/interrupt.h>
+#include <linux/kallsyms.h>
+#include <linux/init.h>
+
+#include <asm/system.h>
+#include <asm/io.h>
+#include <asm/leds.h>
+#include <asm/processor.h>
+#include <asm/uaccess.h>
+
+extern const char *processor_modes[];
+extern void setup_mm_for_reboot(char mode);
+
+static volatile int hlt_counter;
+
+#include <asm/arch/system.h>
+
+void disable_hlt(void)
+{
+ hlt_counter++;
+}
+
+EXPORT_SYMBOL(disable_hlt);
+
+void enable_hlt(void)
+{
+ hlt_counter--;
+}
+
+EXPORT_SYMBOL(enable_hlt);
+
+static int __init nohlt_setup(char *__unused)
+{
+ hlt_counter = 1;
+ return 1;
+}
+
+static int __init hlt_setup(char *__unused)
+{
+ hlt_counter = 0;
+ return 1;
+}
+
+__setup("nohlt", nohlt_setup);
+__setup("hlt", hlt_setup);
+
+/*
+ * The following aren't currently used.
+ */
+void (*pm_idle)(void);
+EXPORT_SYMBOL(pm_idle);
+
+void (*pm_power_off)(void);
+EXPORT_SYMBOL(pm_power_off);
+
+/*
+ * This is our default idle handler. We need to disable
+ * interrupts here to ensure we don't miss a wakeup call.
+ */
+void default_idle(void)
+{
+ local_irq_disable();
+ if (!need_resched() && !hlt_counter)
+ arch_idle();
+ local_irq_enable();
+}
+
+/*
+ * The idle thread. We try to conserve power, while trying to keep
+ * overall latency low. The architecture specific idle is passed
+ * a value to indicate the level of "idleness" of the system.
+ */
+void cpu_idle(void)
+{
+ local_fiq_enable();
+
+ /* endless idle loop with no priority at all */
+ while (1) {
+ void (*idle)(void) = pm_idle;
+ if (!idle)
+ idle = default_idle;
+ preempt_disable();
+ leds_event(led_idle_start);
+ while (!need_resched())
+ idle();
+ leds_event(led_idle_end);
+ preempt_enable();
+ schedule();
+ }
+}
+
+static char reboot_mode = 'h';
+
+int __init reboot_setup(char *str)
+{
+ reboot_mode = str[0];
+ return 1;
+}
+
+__setup("reboot=", reboot_setup);
+
+void machine_halt(void)
+{
+}
+
+EXPORT_SYMBOL(machine_halt);
+
+void machine_power_off(void)
+{
+ if (pm_power_off)
+ pm_power_off();
+}
+
+EXPORT_SYMBOL(machine_power_off);
+
+void machine_restart(char * __unused)
+{
+ /*
+ * Clean and disable cache, and turn off interrupts
+ */
+ cpu_proc_fin();
+
+ /*
+ * Tell the mm system that we are going to reboot -
+ * we may need it to insert some 1:1 mappings so that
+ * soft boot works.
+ */
+ setup_mm_for_reboot(reboot_mode);
+
+ /*
+ * Now call the architecture specific reboot code.
+ */
+ arch_reset(reboot_mode);
+
+ /*
+ * Whoops - the architecture was unable to reboot.
+ * Tell the user!
+ */
+ mdelay(1000);
+ printk("Reboot failed -- System halted\n");
+ while (1);
+}
+
+EXPORT_SYMBOL(machine_restart);
+
+void show_regs(struct pt_regs * regs)
+{
+ unsigned long flags;
+
+ flags = condition_codes(regs);
+
+ print_symbol("PC is at %s\n", instruction_pointer(regs));
+ print_symbol("LR is at %s\n", regs->ARM_lr);
+ printk("pc : [<%08lx>] lr : [<%08lx>] %s\n"
+ "sp : %08lx ip : %08lx fp : %08lx\n",
+ instruction_pointer(regs),
+ regs->ARM_lr, print_tainted(), regs->ARM_sp,
+ regs->ARM_ip, regs->ARM_fp);
+ printk("r10: %08lx r9 : %08lx r8 : %08lx\n",
+ regs->ARM_r10, regs->ARM_r9,
+ regs->ARM_r8);
+ printk("r7 : %08lx r6 : %08lx r5 : %08lx r4 : %08lx\n",
+ regs->ARM_r7, regs->ARM_r6,
+ regs->ARM_r5, regs->ARM_r4);
+ printk("r3 : %08lx r2 : %08lx r1 : %08lx r0 : %08lx\n",
+ regs->ARM_r3, regs->ARM_r2,
+ regs->ARM_r1, regs->ARM_r0);
+ printk("Flags: %c%c%c%c",
+ flags & PSR_N_BIT ? 'N' : 'n',
+ flags & PSR_Z_BIT ? 'Z' : 'z',
+ flags & PSR_C_BIT ? 'C' : 'c',
+ flags & PSR_V_BIT ? 'V' : 'v');
+ printk(" IRQs o%s FIQs o%s Mode %s%s Segment %s\n",
+ interrupts_enabled(regs) ? "n" : "ff",
+ fast_interrupts_enabled(regs) ? "n" : "ff",
+ processor_modes[processor_mode(regs)],
+ thumb_mode(regs) ? " (T)" : "",
+ get_fs() == get_ds() ? "kernel" : "user");
+ {
+ unsigned int ctrl, transbase, dac;
+ __asm__ (
+ " mrc p15, 0, %0, c1, c0\n"
+ " mrc p15, 0, %1, c2, c0\n"
+ " mrc p15, 0, %2, c3, c0\n"
+ : "=r" (ctrl), "=r" (transbase), "=r" (dac));
+ printk("Control: %04X Table: %08X DAC: %08X\n",
+ ctrl, transbase, dac);
+ }
+}
+
+void show_fpregs(struct user_fp *regs)
+{
+ int i;
+
+ for (i = 0; i < 8; i++) {
+ unsigned long *p;
+ char type;
+
+ p = (unsigned long *)(regs->fpregs + i);
+
+ switch (regs->ftype[i]) {
+ case 1: type = 'f'; break;
+ case 2: type = 'd'; break;
+ case 3: type = 'e'; break;
+ default: type = '?'; break;
+ }
+ if (regs->init_flag)
+ type = '?';
+
+ printk(" f%d(%c): %08lx %08lx %08lx%c",
+ i, type, p[0], p[1], p[2], i & 1 ? '\n' : ' ');
+ }
+
+
+ printk("FPSR: %08lx FPCR: %08lx\n",
+ (unsigned long)regs->fpsr,
+ (unsigned long)regs->fpcr);
+}
+
+/*
+ * Task structure and kernel stack allocation.
+ */
+static unsigned long *thread_info_head;
+static unsigned int nr_thread_info;
+
+#define EXTRA_TASK_STRUCT 4
+#define ll_alloc_task_struct() ((struct thread_info *) __get_free_pages(GFP_KERNEL,1))
+#define ll_free_task_struct(p) free_pages((unsigned long)(p),1)
+
+struct thread_info *alloc_thread_info(struct task_struct *task)
+{
+ struct thread_info *thread = NULL;
+
+ if (EXTRA_TASK_STRUCT) {
+ unsigned long *p = thread_info_head;
+
+ if (p) {
+ thread_info_head = (unsigned long *)p[0];
+ nr_thread_info -= 1;
+ }
+ thread = (struct thread_info *)p;
+ }
+
+ if (!thread)
+ thread = ll_alloc_task_struct();
+
+#ifdef CONFIG_MAGIC_SYSRQ
+ /*
+ * The stack must be cleared if you want SYSRQ-T to
+ * give sensible stack usage information
+ */
+ if (thread) {
+ char *p = (char *)thread;
+ memzero(p+KERNEL_STACK_SIZE, KERNEL_STACK_SIZE);
+ }
+#endif
+ return thread;
+}
+
+void free_thread_info(struct thread_info *thread)
+{
+ if (EXTRA_TASK_STRUCT && nr_thread_info < EXTRA_TASK_STRUCT) {
+ unsigned long *p = (unsigned long *)thread;
+ p[0] = (unsigned long)thread_info_head;
+ thread_info_head = p;
+ nr_thread_info += 1;
+ } else
+ ll_free_task_struct(thread);
+}
+
+/*
+ * Free current thread data structures etc..
+ */
+void exit_thread(void)
+{
+}
+
+static void default_fp_init(union fp_state *fp)
+{
+ memset(fp, 0, sizeof(union fp_state));
+}
+
+void (*fp_init)(union fp_state *) = default_fp_init;
+EXPORT_SYMBOL(fp_init);
+
+void flush_thread(void)
+{
+ struct thread_info *thread = current_thread_info();
+ struct task_struct *tsk = current;
+
+ memset(thread->used_cp, 0, sizeof(thread->used_cp));
+ memset(&tsk->thread.debug, 0, sizeof(struct debug_info));
+#if defined(CONFIG_IWMMXT)
+ iwmmxt_task_release(thread);
+#endif
+ fp_init(&thread->fpstate);
+#if defined(CONFIG_VFP)
+ vfp_flush_thread(&thread->vfpstate);
+#endif
+}
+
+void release_thread(struct task_struct *dead_task)
+{
+#if defined(CONFIG_VFP)
+ vfp_release_thread(&dead_task->thread_info->vfpstate);
+#endif
+#if defined(CONFIG_IWMMXT)
+ iwmmxt_task_release(dead_task->thread_info);
+#endif
+}
+
+asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");
+
+int
+copy_thread(int nr, unsigned long clone_flags, unsigned long stack_start,
+ unsigned long stk_sz, struct task_struct *p, struct pt_regs *regs)
+{
+ struct thread_info *thread = p->thread_info;
+ struct pt_regs *childregs;
+
+ childregs = ((struct pt_regs *)((unsigned long)thread + THREAD_SIZE - 8)) - 1;
+ *childregs = *regs;
+ childregs->ARM_r0 = 0;
+ childregs->ARM_sp = stack_start;
+
+ memset(&thread->cpu_context, 0, sizeof(struct cpu_context_save));
+ thread->cpu_context.sp = (unsigned long)childregs;
+ thread->cpu_context.pc = (unsigned long)ret_from_fork;
+
+ if (clone_flags & CLONE_SETTLS)
+ thread->tp_value = regs->ARM_r3;
+
+ return 0;
+}
+
+/*
+ * fill in the fpe structure for a core dump...
+ */
+int dump_fpu (struct pt_regs *regs, struct user_fp *fp)
+{
+ struct thread_info *thread = current_thread_info();
+ int used_math = thread->used_cp[1] | thread->used_cp[2];
+
+ if (used_math)
+ memcpy(fp, &thread->fpstate.soft, sizeof (*fp));
+
+ return used_math != 0;
+}
+EXPORT_SYMBOL(dump_fpu);
+
+/*
+ * fill in the user structure for a core dump..
+ */
+void dump_thread(struct pt_regs * regs, struct user * dump)
+{
+ struct task_struct *tsk = current;
+
+ dump->magic = CMAGIC;
+ dump->start_code = tsk->mm->start_code;
+ dump->start_stack = regs->ARM_sp & ~(PAGE_SIZE - 1);
+
+ dump->u_tsize = (tsk->mm->end_code - tsk->mm->start_code) >> PAGE_SHIFT;
+ dump->u_dsize = (tsk->mm->brk - tsk->mm->start_data + PAGE_SIZE - 1) >> PAGE_SHIFT;
+ dump->u_ssize = 0;
+
+ dump->u_debugreg[0] = tsk->thread.debug.bp[0].address;
+ dump->u_debugreg[1] = tsk->thread.debug.bp[1].address;
+ dump->u_debugreg[2] = tsk->thread.debug.bp[0].insn.arm;
+ dump->u_debugreg[3] = tsk->thread.debug.bp[1].insn.arm;
+ dump->u_debugreg[4] = tsk->thread.debug.nsaved;
+
+ if (dump->start_stack < 0x04000000)
+ dump->u_ssize = (0x04000000 - dump->start_stack) >> PAGE_SHIFT;
+
+ dump->regs = *regs;
+ dump->u_fpvalid = dump_fpu (regs, &dump->u_fp);
+}
+EXPORT_SYMBOL(dump_thread);
+
+/*
+ * Shuffle the argument into the correct register before calling the
+ * thread function. r1 is the thread argument, r2 is the pointer to
+ * the thread function, and r3 points to the exit function.
+ */
+extern void kernel_thread_helper(void);
+asm( ".section .text\n"
+" .align\n"
+" .type kernel_thread_helper, #function\n"
+"kernel_thread_helper:\n"
+" mov r0, r1\n"
+" mov lr, r3\n"
+" mov pc, r2\n"
+" .size kernel_thread_helper, . - kernel_thread_helper\n"
+" .previous");
+
+/*
+ * Create a kernel thread.
+ */
+pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags)
+{
+ struct pt_regs regs;
+
+ memset(&regs, 0, sizeof(regs));
+
+ regs.ARM_r1 = (unsigned long)arg;
+ regs.ARM_r2 = (unsigned long)fn;
+ regs.ARM_r3 = (unsigned long)do_exit;
+ regs.ARM_pc = (unsigned long)kernel_thread_helper;
+ regs.ARM_cpsr = SVC_MODE;
+
+ return do_fork(flags|CLONE_VM|CLONE_UNTRACED, 0, &regs, 0, NULL, NULL);
+}
+EXPORT_SYMBOL(kernel_thread);
+
+unsigned long get_wchan(struct task_struct *p)
+{
+ unsigned long fp, lr;
+ unsigned long stack_page;
+ int count = 0;
+ if (!p || p == current || p->state == TASK_RUNNING)
+ return 0;
+
+ stack_page = 4096 + (unsigned long)p->thread_info;
+ fp = thread_saved_fp(p);
+ do {
+ if (fp < stack_page || fp > 4092+stack_page)
+ return 0;
+ lr = pc_pointer (((unsigned long *)fp)[-1]);
+ if (!in_sched_functions(lr))
+ return lr;
+ fp = *(unsigned long *) (fp - 12);
+ } while (count ++ < 16);
+ return 0;
+}
+EXPORT_SYMBOL(get_wchan);
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