1 files changed, 270 insertions, 0 deletions

diff --git a/arch/cris/arch-v32/kernel/process.c b/arch/cris/arch-v32/kernel/process.c
new file mode 100644
index 000000000000..882be42114f7
--- /dev/null
+++ b/arch/cris/arch-v32/kernel/process.c
@@ -0,0 +1,270 @@
+/*
+ *  Copyright (C) 2000-2003  Axis Communications AB
+ *
+ *  Authors:   Bjorn Wesen (bjornw@axis.com)
+ *             Mikael Starvik (starvik@axis.com)
+ *             Tobias Anderberg (tobiasa@axis.com), CRISv32 port.
+ *
+ * This file handles the architecture-dependent parts of process handling..
+ */
+
+#include <linux/config.h>
+#include <linux/sched.h>
+#include <linux/err.h>
+#include <linux/fs.h>
+#include <linux/slab.h>
+#include <asm/arch/hwregs/reg_rdwr.h>
+#include <asm/arch/hwregs/reg_map.h>
+#include <asm/arch/hwregs/timer_defs.h>
+#include <asm/arch/hwregs/intr_vect_defs.h>
+
+extern void stop_watchdog(void);
+
+#ifdef CONFIG_ETRAX_GPIO
+extern void etrax_gpio_wake_up_check(void); /* Defined in drivers/gpio.c. */
+#endif
+
+extern int cris_hlt_counter;
+
+/* We use this if we don't have any better idle routine. */
+void default_idle(void)
+{
+        local_irq_disable();
+        if (!need_resched() && !cris_hlt_counter) {
+                /* Halt until exception. */
+                __asm__ volatile("ei    \n\t"
+                                 "halt      ");
+        }
+        local_irq_enable();
+}
+
+/*
+ * Free current thread data structures etc..
+ */
+
+extern void deconfigure_bp(long pid);
+void exit_thread(void)
+{
+        deconfigure_bp(current->pid);
+}
+
+/*
+ * If the watchdog is enabled, disable interrupts and enter an infinite loop.
+ * The watchdog will reset the CPU after 0.1s. If the watchdog isn't enabled
+ * then enable it and wait.
+ */
+extern void arch_enable_nmi(void);
+
+void
+hard_reset_now(void)
+{
+        /*
+         * Don't declare this variable elsewhere.  We don't want any other
+         * code to know about it than the watchdog handler in entry.S and
+         * this code, implementing hard reset through the watchdog.
+         */
+#if defined(CONFIG_ETRAX_WATCHDOG)
+        extern int cause_of_death;
+#endif
+
+        printk("*** HARD RESET ***\n");
+        local_irq_disable();
+
+#if defined(CONFIG_ETRAX_WATCHDOG)
+        cause_of_death = 0xbedead;
+#else
+{
+        reg_timer_rw_wd_ctrl wd_ctrl = {0};
+
+        stop_watchdog();
+
+        wd_ctrl.key = 16;       /* Arbitrary key. */
+        wd_ctrl.cnt = 1;        /* Minimum time. */
+        wd_ctrl.cmd = regk_timer_start;
+
+        arch_enable_nmi();
+        REG_WR(timer, regi_timer, rw_wd_ctrl, wd_ctrl);
+}
+#endif
+
+        while (1)
+                ; /* Wait for reset. */
+}
+
+/*
+ * Return saved PC of a blocked thread.
+ */
+unsigned long thread_saved_pc(struct task_struct *t)
+{
+        return (unsigned long)user_regs(t->thread_info)->erp;
+}
+
+static void
+kernel_thread_helper(void* dummy, int (*fn)(void *), void * arg)
+{
+        fn(arg);
+        do_exit(-1); /* Should never be called, return bad exit value. */
+}
+
+/* Create a kernel thread. */
+int
+kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
+{
+        struct pt_regs regs;
+
+        memset(&regs, 0, sizeof(regs));
+
+        /* Don't use r10 since that is set to 0 in copy_thread. */
+        regs.r11 = (unsigned long) fn;
+        regs.r12 = (unsigned long) arg;
+        regs.erp = (unsigned long) kernel_thread_helper;
+        regs.ccs = 1 << (I_CCS_BITNR + CCS_SHIFT);
+
+        /* Create the new process. */
+        return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0, &regs, 0, NULL, NULL);
+}
+
+/*
+ * Setup the child's kernel stack with a pt_regs and call switch_stack() on it.
+ * It will be unnested during _resume and _ret_from_sys_call when the new thread
+ * is scheduled.
+ *
+ * Also setup the thread switching structure which is used to keep
+ * thread-specific data during _resumes.
+ */
+
+extern asmlinkage void ret_from_fork(void);
+
+int
+copy_thread(int nr, unsigned long clone_flags, unsigned long usp,
+        unsigned long unused,
+        struct task_struct *p, struct pt_regs *regs)
+{
+        struct pt_regs *childregs;
+        struct switch_stack *swstack;
+
+        /*
+         * Put the pt_regs structure at the end of the new kernel stack page and
+         * fix it up. Note: the task_struct doubles as the kernel stack for the
+         * task.
+         */
+        childregs = user_regs(p->thread_info);
+        *childregs = *regs;     /* Struct copy of pt_regs. */
+        p->set_child_tid = p->clear_child_tid = NULL;
+        childregs->r10 = 0;     /* Child returns 0 after a fork/clone. */
+
+        /* Set a new TLS ?
+         * The TLS is in $mof beacuse it is the 5th argument to sys_clone.
+         */
+        if (p->mm && (clone_flags & CLONE_SETTLS)) {
+                p->thread_info->tls = regs->mof;
+        }
+
+        /* Put the switch stack right below the pt_regs. */
+        swstack = ((struct switch_stack *) childregs) - 1;
+
+        /* Paramater to ret_from_sys_call. 0 is don't restart the syscall. */
+        swstack->r9 = 0;
+
+        /*
+         * We want to return into ret_from_sys_call after the _resume.
+         * ret_from_fork will call ret_from_sys_call.
+         */
+        swstack->return_ip = (unsigned long) ret_from_fork;
+
+        /* Fix the user-mode and kernel-mode stackpointer. */
+        p->thread.usp = usp;
+        p->thread.ksp = (unsigned long) swstack;
+
+        return 0;
+}
+
+/*
+ * Be aware of the "magic" 7th argument in the four system-calls below.
+ * They need the latest stackframe, which is put as the 7th argument by
+ * entry.S. The previous arguments are dummies or actually used, but need
+ * to be defined to reach the 7th argument.
+ *
+ * N.B.: Another method to get the stackframe is to use current_regs(). But
+ * it returns the latest stack-frame stacked when going from _user mode_ and
+ * some of these (at least sys_clone) are called from kernel-mode sometimes
+ * (for example during kernel_thread, above) and thus cannot use it. Thus,
+ * to be sure not to get any surprises, we use the method for the other calls
+ * as well.
+ */
+asmlinkage int
+sys_fork(long r10, long r11, long r12, long r13, long mof, long srp,
+        struct pt_regs *regs)
+{
+        return do_fork(SIGCHLD, rdusp(), regs, 0, NULL, NULL);
+}
+
+/* FIXME: Is parent_tid/child_tid really third/fourth argument? Update lib? */
+asmlinkage int
+sys_clone(unsigned long newusp, unsigned long flags, int *parent_tid, int *child_tid,
+        unsigned long tls, long srp, struct pt_regs *regs)
+{
+        if (!newusp)
+                newusp = rdusp();
+
+        return do_fork(flags, newusp, regs, 0, parent_tid, child_tid);
+}
+
+/*
+ * vfork is a system call in i386 because of register-pressure - maybe
+ * we can remove it and handle it in libc but we put it here until then.
+ */
+asmlinkage int
+sys_vfork(long r10, long r11, long r12, long r13, long mof, long srp,
+        struct pt_regs *regs)
+{
+        return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, rdusp(), regs, 0, NULL, NULL);
+}
+
+/* sys_execve() executes a new program. */
+asmlinkage int
+sys_execve(const char *fname, char **argv, char **envp, long r13, long mof, long srp,
+        struct pt_regs *regs)
+{
+        int error;
+        char *filename;
+
+        filename = getname(fname);
+        error = PTR_ERR(filename);
+
+        if (IS_ERR(filename))
+                goto out;
+
+        error = do_execve(filename, argv, envp, regs);
+        putname(filename);
+ out:
+        return error;
+}
+
+unsigned long
+get_wchan(struct task_struct *p)
+{
+        /* TODO */
+        return 0;
+}
+#undef last_sched
+#undef first_sched
+
+void show_regs(struct pt_regs * regs)
+{
+        unsigned long usp = rdusp();
+        printk("ERP: %08lx SRP: %08lx  CCS: %08lx USP: %08lx MOF: %08lx\n",
+                regs->erp, regs->srp, regs->ccs, usp, regs->mof);
+
+        printk(" r0: %08lx  r1: %08lx   r2: %08lx  r3: %08lx\n",
+                regs->r0, regs->r1, regs->r2, regs->r3);
+
+        printk(" r4: %08lx  r5: %08lx   r6: %08lx  r7: %08lx\n",
+                regs->r4, regs->r5, regs->r6, regs->r7);
+
+        printk(" r8: %08lx  r9: %08lx  r10: %08lx r11: %08lx\n",
+                regs->r8, regs->r9, regs->r10, regs->r11);
+
+        printk("r12: %08lx r13: %08lx oR10: %08lx\n",
+                regs->r12, regs->r13, regs->orig_r10);
+}