Subversion Repositories or1k_soc_on_altera_embedded_dev_kit

/*  linux/arch/sparc/kernel/process.c

 *

 *  Copyright (C) 1995 David S. Miller (davem@davemloft.net)

 *  Copyright (C) 1996 Eddie C. Dost   (ecd@skynet.be)

 */

/*

 * This file handles the architecture-dependent parts of process handling..

 */

#include <stdarg.h>

#include <linux/errno.h>

#include <linux/module.h>

#include <linux/sched.h>

#include <linux/kernel.h>

#include <linux/kallsyms.h>

#include <linux/mm.h>

#include <linux/stddef.h>

#include <linux/ptrace.h>

#include <linux/slab.h>

#include <linux/user.h>

#include <linux/a.out.h>

#include <linux/smp.h>

#include <linux/reboot.h>

#include <linux/delay.h>

#include <linux/pm.h>

#include <linux/init.h>

#include <asm/auxio.h>

#include <asm/oplib.h>

#include <asm/uaccess.h>

#include <asm/system.h>

#include <asm/page.h>

#include <asm/pgalloc.h>

#include <asm/pgtable.h>

#include <asm/delay.h>

#include <asm/processor.h>

#include <asm/psr.h>

#include <asm/elf.h>

#include <asm/prom.h>

#include <asm/unistd.h>

/*

 * Power management idle function

 * Set in pm platform drivers (apc.c and pmc.c)

 */

void (*pm_idle)(void);

/*

 * Power-off handler instantiation for pm.h compliance

 * This is done via auxio, but could be used as a fallback

 * handler when auxio is not present-- unused for now...

 */

void (*pm_power_off)(void) = machine_power_off;

EXPORT_SYMBOL(pm_power_off);

/*

 * sysctl - toggle power-off restriction for serial console

 * systems in machine_power_off()

 */

int scons_pwroff = 1;

extern void fpsave(unsigned long *, unsigned long *, void *, unsigned long *);

struct task_struct *last_task_used_math = NULL;

struct thread_info *current_set[NR_CPUS];

#ifndef CONFIG_SMP

#define SUN4C_FAULT_HIGH 100

/*

 * the idle loop on a Sparc... ;)

 */

void cpu_idle(void)

{

        /* endless idle loop with no priority at all */

        for (;;) {

                if (ARCH_SUN4C_SUN4) {

                        static int count = HZ;

                        static unsigned long last_jiffies;

                        static unsigned long last_faults;

                        static unsigned long fps;

                        unsigned long now;

                        unsigned long faults;

                        extern unsigned long sun4c_kernel_faults;

                        extern void sun4c_grow_kernel_ring(void);

                        local_irq_disable();

                        now = jiffies;

                        count -= (now - last_jiffies);

                        last_jiffies = now;

                        if (count < 0) {

                                count += HZ;

                                faults = sun4c_kernel_faults;

                                fps = (fps + (faults - last_faults)) >> 1;

                                last_faults = faults;

#if 0

                                printk("kernel faults / second = %ld\n", fps);

#endif

                                if (fps >= SUN4C_FAULT_HIGH) {

                                        sun4c_grow_kernel_ring();

                                }

                        }

                        local_irq_enable();

                }

                if (pm_idle) {

                        while (!need_resched())

                                (*pm_idle)();

                } else {

                        while (!need_resched())

                                cpu_relax();

                }

                preempt_enable_no_resched();

                schedule();

                preempt_disable();

                check_pgt_cache();

        }

}

#else

/* This is being executed in task 0 'user space'. */

void cpu_idle(void)

{

        set_thread_flag(TIF_POLLING_NRFLAG);

        /* endless idle loop with no priority at all */

        while(1) {

                while (!need_resched())

                        cpu_relax();

                preempt_enable_no_resched();

                schedule();

                preempt_disable();

                check_pgt_cache();

        }

}

#endif

extern char reboot_command [];

extern void (*prom_palette)(int);

/* XXX cli/sti -> local_irq_xxx here, check this works once SMP is fixed. */

void machine_halt(void)

{

        local_irq_enable();

        mdelay(8);

        local_irq_disable();

        if (prom_palette)

                prom_palette (1);

        prom_halt();

        panic("Halt failed!");

}

void machine_restart(char * cmd)

{

        char *p;

        local_irq_enable();

        mdelay(8);

        local_irq_disable();

        p = strchr (reboot_command, '\n');

        if (p) *p = 0;

        if (prom_palette)

                prom_palette (1);

        if (cmd)

                prom_reboot(cmd);

        if (*reboot_command)

                prom_reboot(reboot_command);

        prom_feval ("reset");

        panic("Reboot failed!");

}

void machine_power_off(void)

{

#ifdef CONFIG_SUN_AUXIO

        if (auxio_power_register &&

            (strcmp(of_console_device->type, "serial") || scons_pwroff))

                *auxio_power_register |= AUXIO_POWER_OFF;

#endif

        machine_halt();

}

static DEFINE_SPINLOCK(sparc_backtrace_lock);

void __show_backtrace(unsigned long fp)

{

        struct reg_window *rw;

        unsigned long flags;

        int cpu = smp_processor_id();

        spin_lock_irqsave(&sparc_backtrace_lock, flags);

        rw = (struct reg_window *)fp;

        while(rw && (((unsigned long) rw) >= PAGE_OFFSET) &&

            !(((unsigned long) rw) & 0x7)) {

                printk("CPU[%d]: ARGS[%08lx,%08lx,%08lx,%08lx,%08lx,%08lx] "

                       "FP[%08lx] CALLER[%08lx]: ", cpu,

                       rw->ins[0], rw->ins[1], rw->ins[2], rw->ins[3],

                       rw->ins[4], rw->ins[5],

                       rw->ins[6],

                       rw->ins[7]);

                print_symbol("%s\n", rw->ins[7]);

                rw = (struct reg_window *) rw->ins[6];

        }

        spin_unlock_irqrestore(&sparc_backtrace_lock, flags);

}

#define __SAVE __asm__ __volatile__("save %sp, -0x40, %sp\n\t")

#define __RESTORE __asm__ __volatile__("restore %g0, %g0, %g0\n\t")

#define __GET_FP(fp) __asm__ __volatile__("mov %%i6, %0" : "=r" (fp))

void show_backtrace(void)

{

        unsigned long fp;

        __SAVE; __SAVE; __SAVE; __SAVE;

        __SAVE; __SAVE; __SAVE; __SAVE;

        __RESTORE; __RESTORE; __RESTORE; __RESTORE;

        __RESTORE; __RESTORE; __RESTORE; __RESTORE;

        __GET_FP(fp);

        __show_backtrace(fp);

}

#ifdef CONFIG_SMP

void smp_show_backtrace_all_cpus(void)

{

        xc0((smpfunc_t) show_backtrace);

        show_backtrace();

}

#endif

#if 0

void show_stackframe(struct sparc_stackf *sf)

{

        unsigned long size;

        unsigned long *stk;

        int i;

        printk("l0: %08lx l1: %08lx l2: %08lx l3: %08lx "

               "l4: %08lx l5: %08lx l6: %08lx l7: %08lx\n",

               sf->locals[0], sf->locals[1], sf->locals[2], sf->locals[3],

               sf->locals[4], sf->locals[5], sf->locals[6], sf->locals[7]);

        printk("i0: %08lx i1: %08lx i2: %08lx i3: %08lx "

               "i4: %08lx i5: %08lx fp: %08lx i7: %08lx\n",

               sf->ins[0], sf->ins[1], sf->ins[2], sf->ins[3],

               sf->ins[4], sf->ins[5], (unsigned long)sf->fp, sf->callers_pc);

        printk("sp: %08lx x0: %08lx x1: %08lx x2: %08lx "

               "x3: %08lx x4: %08lx x5: %08lx xx: %08lx\n",

               (unsigned long)sf->structptr, sf->xargs[0], sf->xargs[1],

               sf->xargs[2], sf->xargs[3], sf->xargs[4], sf->xargs[5],

               sf->xxargs[0]);

        size = ((unsigned long)sf->fp) - ((unsigned long)sf);

        size -= STACKFRAME_SZ;

        stk = (unsigned long *)((unsigned long)sf + STACKFRAME_SZ);

        i = 0;

        do {

                printk("s%d: %08lx\n", i++, *stk++);

        } while ((size -= sizeof(unsigned long)));

}

#endif

void show_regs(struct pt_regs *r)

{

        struct reg_window *rw = (struct reg_window *) r->u_regs[14];

        printk("PSR: %08lx PC: %08lx NPC: %08lx Y: %08lx    %s\n",

               r->psr, r->pc, r->npc, r->y, print_tainted());

        print_symbol("PC: <%s>\n", r->pc);

        printk("%%G: %08lx %08lx  %08lx %08lx  %08lx %08lx  %08lx %08lx\n",

               r->u_regs[0], r->u_regs[1], r->u_regs[2], r->u_regs[3],

               r->u_regs[4], r->u_regs[5], r->u_regs[6], r->u_regs[7]);

        printk("%%O: %08lx %08lx  %08lx %08lx  %08lx %08lx  %08lx %08lx\n",

               r->u_regs[8], r->u_regs[9], r->u_regs[10], r->u_regs[11],

               r->u_regs[12], r->u_regs[13], r->u_regs[14], r->u_regs[15]);

        print_symbol("RPC: <%s>\n", r->u_regs[15]);

        printk("%%L: %08lx %08lx  %08lx %08lx  %08lx %08lx  %08lx %08lx\n",

               rw->locals[0], rw->locals[1], rw->locals[2], rw->locals[3],

               rw->locals[4], rw->locals[5], rw->locals[6], rw->locals[7]);

        printk("%%I: %08lx %08lx  %08lx %08lx  %08lx %08lx  %08lx %08lx\n",

               rw->ins[0], rw->ins[1], rw->ins[2], rw->ins[3],

               rw->ins[4], rw->ins[5], rw->ins[6], rw->ins[7]);

}

/*

 * The show_stack is an external API which we do not use ourselves.

 * The oops is printed in die_if_kernel.

 */

void show_stack(struct task_struct *tsk, unsigned long *_ksp)

{

        unsigned long pc, fp;

        unsigned long task_base;

        struct reg_window *rw;

        int count = 0;

        if (tsk != NULL)

                task_base = (unsigned long) task_stack_page(tsk);

        else

                task_base = (unsigned long) current_thread_info();

        fp = (unsigned long) _ksp;

        do {

                /* Bogus frame pointer? */

                if (fp < (task_base + sizeof(struct thread_info)) ||

                    fp >= (task_base + (PAGE_SIZE << 1)))

                        break;

                rw = (struct reg_window *) fp;

                pc = rw->ins[7];

                printk("[%08lx : ", pc);

                print_symbol("%s ] ", pc);

                fp = rw->ins[6];

        } while (++count < 16);

        printk("\n");

}

void dump_stack(void)

{

        unsigned long *ksp;

        __asm__ __volatile__("mov       %%fp, %0"

                             : "=r" (ksp));

        show_stack(current, ksp);

}

EXPORT_SYMBOL(dump_stack);

/*

 * Note: sparc64 has a pretty intricated thread_saved_pc, check it out.

 */

unsigned long thread_saved_pc(struct task_struct *tsk)

{

        return task_thread_info(tsk)->kpc;

}

/*

 * Free current thread data structures etc..

 */

void exit_thread(void)

{

#ifndef CONFIG_SMP

        if(last_task_used_math == current) {

#else

        if (test_thread_flag(TIF_USEDFPU)) {

#endif

                /* Keep process from leaving FPU in a bogon state. */

                put_psr(get_psr() | PSR_EF);

                fpsave(&current->thread.float_regs[0], &current->thread.fsr,

                       &current->thread.fpqueue[0], &current->thread.fpqdepth);

#ifndef CONFIG_SMP

                last_task_used_math = NULL;

#else

                clear_thread_flag(TIF_USEDFPU);

#endif

        }

}

void flush_thread(void)

{

        current_thread_info()->w_saved = 0;

        /* No new signal delivery by default */

        current->thread.new_signal = 0;

#ifndef CONFIG_SMP

        if(last_task_used_math == current) {

#else

        if (test_thread_flag(TIF_USEDFPU)) {

#endif

                /* Clean the fpu. */

                put_psr(get_psr() | PSR_EF);

                fpsave(&current->thread.float_regs[0], &current->thread.fsr,

                       &current->thread.fpqueue[0], &current->thread.fpqdepth);

#ifndef CONFIG_SMP

                last_task_used_math = NULL;

#else

                clear_thread_flag(TIF_USEDFPU);

#endif

        }

        /* Now, this task is no longer a kernel thread. */

        current->thread.current_ds = USER_DS;

        if (current->thread.flags & SPARC_FLAG_KTHREAD) {

                current->thread.flags &= ~SPARC_FLAG_KTHREAD;

                /* We must fixup kregs as well. */

                /* XXX This was not fixed for ti for a while, worked. Unused? */

                current->thread.kregs = (struct pt_regs *)

                    (task_stack_page(current) + (THREAD_SIZE - TRACEREG_SZ));

        }

}

static inline struct sparc_stackf __user *

clone_stackframe(struct sparc_stackf __user *dst,

                 struct sparc_stackf __user *src)

{

        unsigned long size, fp;

        struct sparc_stackf *tmp;

        struct sparc_stackf __user *sp;

        if (get_user(tmp, &src->fp))

                return NULL;

        fp = (unsigned long) tmp;

        size = (fp - ((unsigned long) src));

        fp = (unsigned long) dst;

        sp = (struct sparc_stackf __user *)(fp - size);

        /* do_fork() grabs the parent semaphore, we must release it

         * temporarily so we can build the child clone stack frame

         * without deadlocking.

         */

        if (__copy_user(sp, src, size))

                sp = NULL;

        else if (put_user(fp, &sp->fp))

                sp = NULL;

        return sp;

}

asmlinkage int sparc_do_fork(unsigned long clone_flags,

                             unsigned long stack_start,

                             struct pt_regs *regs,

                             unsigned long stack_size)

{

        unsigned long parent_tid_ptr, child_tid_ptr;

        parent_tid_ptr = regs->u_regs[UREG_I2];

        child_tid_ptr = regs->u_regs[UREG_I4];

        return do_fork(clone_flags, stack_start,

                       regs, stack_size,

                       (int __user *) parent_tid_ptr,

                       (int __user *) child_tid_ptr);

}

/* Copy a Sparc thread.  The fork() return value conventions

 * under SunOS are nothing short of bletcherous:

 * Parent -->  %o0 == childs  pid, %o1 == 0

 * Child  -->  %o0 == parents pid, %o1 == 1

 *

 * NOTE: We have a separate fork kpsr/kwim because

 *       the parent could change these values between

 *       sys_fork invocation and when we reach here

 *       if the parent should sleep while trying to

 *       allocate the task_struct and kernel stack in

 *       do_fork().

 * XXX See comment above sys_vfork in sparc64. todo.

 */

extern void ret_from_fork(void);

int copy_thread(int nr, unsigned long clone_flags, unsigned long sp,

                unsigned long unused,

                struct task_struct *p, struct pt_regs *regs)

{

        struct thread_info *ti = task_thread_info(p);

        struct pt_regs *childregs;

        char *new_stack;

#ifndef CONFIG_SMP

        if(last_task_used_math == current) {

#else

        if (test_thread_flag(TIF_USEDFPU)) {

#endif

                put_psr(get_psr() | PSR_EF);

                fpsave(&p->thread.float_regs[0], &p->thread.fsr,

                       &p->thread.fpqueue[0], &p->thread.fpqdepth);

#ifdef CONFIG_SMP

                clear_thread_flag(TIF_USEDFPU);

#endif

        }

        /*

         *  p->thread_info         new_stack   childregs

         *  !                      !           !             {if(PSR_PS) }

         *  V                      V (stk.fr.) V  (pt_regs)  { (stk.fr.) }

         *  +----- - - - - - ------+===========+============={+==========}+

         */

        new_stack = task_stack_page(p) + THREAD_SIZE;

        if (regs->psr & PSR_PS)

                new_stack -= STACKFRAME_SZ;

        new_stack -= STACKFRAME_SZ + TRACEREG_SZ;

        memcpy(new_stack, (char *)regs - STACKFRAME_SZ, STACKFRAME_SZ + TRACEREG_SZ);

        childregs = (struct pt_regs *) (new_stack + STACKFRAME_SZ);

        /*

         * A new process must start with interrupts closed in 2.5,

         * because this is how Mingo's scheduler works (see schedule_tail

         * and finish_arch_switch). If we do not do it, a timer interrupt hits

         * before we unlock, attempts to re-take the rq->lock, and then we die.

         * Thus, kpsr|=PSR_PIL.

         */

        ti->ksp = (unsigned long) new_stack;

        ti->kpc = (((unsigned long) ret_from_fork) - 0x8);

        ti->kpsr = current->thread.fork_kpsr | PSR_PIL;

        ti->kwim = current->thread.fork_kwim;

        if(regs->psr & PSR_PS) {

                extern struct pt_regs fake_swapper_regs;

                p->thread.kregs = &fake_swapper_regs;

                new_stack += STACKFRAME_SZ + TRACEREG_SZ;

                childregs->u_regs[UREG_FP] = (unsigned long) new_stack;

                p->thread.flags |= SPARC_FLAG_KTHREAD;

                p->thread.current_ds = KERNEL_DS;

                memcpy(new_stack, (void *)regs->u_regs[UREG_FP], STACKFRAME_SZ);

                childregs->u_regs[UREG_G6] = (unsigned long) ti;

        } else {

                p->thread.kregs = childregs;

                childregs->u_regs[UREG_FP] = sp;

                p->thread.flags &= ~SPARC_FLAG_KTHREAD;

                p->thread.current_ds = USER_DS;

                if (sp != regs->u_regs[UREG_FP]) {

                        struct sparc_stackf __user *childstack;

                        struct sparc_stackf __user *parentstack;

                        /*

                         * This is a clone() call with supplied user stack.

                         * Set some valid stack frames to give to the child.

                         */

                        childstack = (struct sparc_stackf __user *)

                                (sp & ~0x7UL);

                        parentstack = (struct sparc_stackf __user *)

                                regs->u_regs[UREG_FP];

#if 0

                        printk("clone: parent stack:\n");

                        show_stackframe(parentstack);

#endif

                        childstack = clone_stackframe(childstack, parentstack);

                        if (!childstack)

                                return -EFAULT;

#if 0

                        printk("clone: child stack:\n");

                        show_stackframe(childstack);

#endif

                        childregs->u_regs[UREG_FP] = (unsigned long)childstack;

                }

        }

#ifdef CONFIG_SMP

        /* FPU must be disabled on SMP. */

        childregs->psr &= ~PSR_EF;

#endif

        /* Set the return value for the child. */

        childregs->u_regs[UREG_I0] = current->pid;

        childregs->u_regs[UREG_I1] = 1;

        /* Set the return value for the parent. */

        regs->u_regs[UREG_I1] = 0;

        if (clone_flags & CLONE_SETTLS)

                childregs->u_regs[UREG_G7] = regs->u_regs[UREG_I3];

        return 0;

}

/*

 * fill in the user structure for a core dump..

 */

void dump_thread(struct pt_regs * regs, struct user * dump)

{

        unsigned long first_stack_page;

        dump->magic = SUNOS_CORE_MAGIC;

        dump->len = sizeof(struct user);

        dump->regs.psr = regs->psr;

        dump->regs.pc = regs->pc;

        dump->regs.npc = regs->npc;

        dump->regs.y = regs->y;

        /* fuck me plenty */

        memcpy(&dump->regs.regs[0], &regs->u_regs[1], (sizeof(unsigned long) * 15));

        dump->uexec = current->thread.core_exec;

        dump->u_tsize = (((unsigned long) current->mm->end_code) -

                ((unsigned long) current->mm->start_code)) & ~(PAGE_SIZE - 1);

        dump->u_dsize = ((unsigned long) (current->mm->brk + (PAGE_SIZE-1)));

        dump->u_dsize -= dump->u_tsize;

        dump->u_dsize &= ~(PAGE_SIZE - 1);

        first_stack_page = (regs->u_regs[UREG_FP] & ~(PAGE_SIZE - 1));

        dump->u_ssize = (TASK_SIZE - first_stack_page) & ~(PAGE_SIZE - 1);

        memcpy(&dump->fpu.fpstatus.fregs.regs[0], &current->thread.float_regs[0], (sizeof(unsigned long) * 32));

        dump->fpu.fpstatus.fsr = current->thread.fsr;

        dump->fpu.fpstatus.flags = dump->fpu.fpstatus.extra = 0;

        dump->fpu.fpstatus.fpq_count = current->thread.fpqdepth;

        memcpy(&dump->fpu.fpstatus.fpq[0], &current->thread.fpqueue[0],

               ((sizeof(unsigned long) * 2) * 16));

        dump->sigcode = 0;

}

/*

 * fill in the fpu structure for a core dump.

 */

int dump_fpu (struct pt_regs * regs, elf_fpregset_t * fpregs)

{

        if (used_math()) {

                memset(fpregs, 0, sizeof(*fpregs));

                fpregs->pr_q_entrysize = 8;

                return 1;

        }

#ifdef CONFIG_SMP

        if (test_thread_flag(TIF_USEDFPU)) {

                put_psr(get_psr() | PSR_EF);

                fpsave(&current->thread.float_regs[0], &current->thread.fsr,

                       &current->thread.fpqueue[0], &current->thread.fpqdepth);

                if (regs != NULL) {

                        regs->psr &= ~(PSR_EF);

                        clear_thread_flag(TIF_USEDFPU);

                }

        }

#else

        if (current == last_task_used_math) {

                put_psr(get_psr() | PSR_EF);

                fpsave(&current->thread.float_regs[0], &current->thread.fsr,

                       &current->thread.fpqueue[0], &current->thread.fpqdepth);