--- /dev/null
+/* process.c: FRV specific parts of process handling
+ *
+ * Copyright (C) 2003-5 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ * - Derived from arch/m68k/kernel/process.c
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/config.h>
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/smp_lock.h>
+#include <linux/stddef.h>
+#include <linux/unistd.h>
+#include <linux/ptrace.h>
+#include <linux/slab.h>
+#include <linux/user.h>
+#include <linux/elf.h>
+#include <linux/reboot.h>
+#include <linux/interrupt.h>
+
+#include <asm/uaccess.h>
+#include <asm/system.h>
+#include <asm/setup.h>
+#include <asm/pgtable.h>
+#include <asm/gdb-stub.h>
+#include <asm/mb-regs.h>
+
+#include "local.h"
+
+asmlinkage void ret_from_fork(void);
+
+#include <asm/pgalloc.h>
+
+struct task_struct *alloc_task_struct(void)
+{
+ struct task_struct *p = kmalloc(THREAD_SIZE, GFP_KERNEL);
+ if (p)
+ atomic_set((atomic_t *)(p+1), 1);
+ return p;
+}
+
+void free_task_struct(struct task_struct *p)
+{
+ if (atomic_dec_and_test((atomic_t *)(p+1)))
+ kfree(p);
+}
+
+static void core_sleep_idle(void)
+{
+#ifdef LED_DEBUG_SLEEP
+ /* Show that we're sleeping... */
+ __set_LEDS(0x55aa);
+#endif
+ frv_cpu_core_sleep();
+#ifdef LED_DEBUG_SLEEP
+ /* ... and that we woke up */
+ __set_LEDS(0);
+#endif
+ mb();
+}
+
+void (*idle)(void) = core_sleep_idle;
+
+/*
+ * The idle thread. There's no useful work to be
+ * done, so just try to conserve power and have a
+ * low exit latency (ie sit in a loop waiting for
+ * somebody to say that they'd like to reschedule)
+ */
+void cpu_idle(void)
+{
+ /* endless idle loop with no priority at all */
+ while (1) {
+ while (!need_resched()) {
+ irq_stat[smp_processor_id()].idle_timestamp = jiffies;
+
+ if (!frv_dma_inprogress && idle)
+ idle();
+ }
+
+ schedule();
+ }
+}
+
+void machine_restart(char * __unused)
+{
+ unsigned long reset_addr;
+#ifdef CONFIG_GDBSTUB
+ gdbstub_exit(0);
+#endif
+
+ if (PSR_IMPLE(__get_PSR()) == PSR_IMPLE_FR551)
+ reset_addr = 0xfefff500;
+ else
+ reset_addr = 0xfeff0500;
+
+ /* Software reset. */
+ asm volatile(" dcef @(gr0,gr0),1 ! membar !"
+ " sti %1,@(%0,0) !"
+ " nop ! nop ! nop ! nop ! nop ! "
+ " nop ! nop ! nop ! nop ! nop ! "
+ " nop ! nop ! nop ! nop ! nop ! "
+ " nop ! nop ! nop ! nop ! nop ! "
+ : : "r" (reset_addr), "r" (1) );
+
+ for (;;)
+ ;
+}
+
+void machine_halt(void)
+{
+#ifdef CONFIG_GDBSTUB
+ gdbstub_exit(0);
+#endif
+
+ for (;;);
+}
+
+void machine_power_off(void)
+{
+#ifdef CONFIG_GDBSTUB
+ gdbstub_exit(0);
+#endif
+
+ for (;;);
+}
+
+void flush_thread(void)
+{
+#if 0 //ndef NO_FPU
+ unsigned long zero = 0;
+#endif
+ set_fs(USER_DS);
+}
+
+inline unsigned long user_stack(const struct pt_regs *regs)
+{
+ while (regs->next_frame)
+ regs = regs->next_frame;
+ return user_mode(regs) ? regs->sp : 0;
+}
+
+asmlinkage int sys_fork(void)
+{
+#ifndef CONFIG_MMU
+ /* fork almost works, enough to trick you into looking elsewhere:-( */
+ return -EINVAL;
+#else
+ return do_fork(SIGCHLD, user_stack(__frame), __frame, 0, NULL, NULL);
+#endif
+}
+
+asmlinkage int sys_vfork(void)
+{
+ return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, user_stack(__frame), __frame, 0,
+ NULL, NULL);
+}
+
+/*****************************************************************************/
+/*
+ * clone a process
+ * - tlsptr is retrieved by copy_thread()
+ */
+asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
+ int __user *parent_tidptr, int __user *child_tidptr,
+ int __user *tlsptr)
+{
+ if (!newsp)
+ newsp = user_stack(__frame);
+ return do_fork(clone_flags, newsp, __frame, 0, parent_tidptr, child_tidptr);
+} /* end sys_clone() */
+
+/*****************************************************************************/
+/*
+ * This gets called before we allocate a new thread and copy
+ * the current task into it.
+ */
+void prepare_to_copy(struct task_struct *tsk)
+{
+ //unlazy_fpu(tsk);
+} /* end prepare_to_copy() */
+
+/*****************************************************************************/
+/*
+ * set up the kernel stack and exception frames for a new process
+ */
+int copy_thread(int nr, unsigned long clone_flags,
+ unsigned long usp, unsigned long topstk,
+ struct task_struct *p, struct pt_regs *regs)
+{
+ struct pt_regs *childregs0, *childregs, *regs0;
+
+ regs0 = __kernel_frame0_ptr;
+ childregs0 = (struct pt_regs *)
+ ((unsigned long) p->thread_info + THREAD_SIZE - USER_CONTEXT_SIZE);
+ childregs = childregs0;
+
+ /* set up the userspace frame (the only place that the USP is stored) */
+ *childregs0 = *regs0;
+
+ childregs0->gr8 = 0;
+ childregs0->sp = usp;
+ childregs0->next_frame = NULL;
+
+ /* set up the return kernel frame if called from kernel_thread() */
+ if (regs != regs0) {
+ childregs--;
+ *childregs = *regs;
+ childregs->sp = (unsigned long) childregs0;
+ childregs->next_frame = childregs0;
+ childregs->gr15 = (unsigned long) p->thread_info;
+ childregs->gr29 = (unsigned long) p;
+ }
+
+ p->set_child_tid = p->clear_child_tid = NULL;
+
+ p->thread.frame = childregs;
+ p->thread.curr = p;
+ p->thread.sp = (unsigned long) childregs;
+ p->thread.fp = 0;
+ p->thread.lr = 0;
+ p->thread.pc = (unsigned long) ret_from_fork;
+ p->thread.frame0 = childregs0;
+
+ /* the new TLS pointer is passed in as arg #5 to sys_clone() */
+ if (clone_flags & CLONE_SETTLS)
+ childregs->gr29 = childregs->gr12;
+
+ save_user_regs(p->thread.user);
+
+ return 0;
+} /* end copy_thread() */
+
+/*
+ * fill in the user structure for a core dump..
+ */
+void dump_thread(struct pt_regs *regs, struct user *dump)
+{
+#if 0
+ /* changed the size calculations - should hopefully work better. lbt */
+ dump->magic = CMAGIC;
+ dump->start_code = 0;
+ dump->start_stack = user_stack(regs) & ~(PAGE_SIZE - 1);
+ dump->u_tsize = ((unsigned long) current->mm->end_code) >> PAGE_SHIFT;
+ dump->u_dsize = ((unsigned long) (current->mm->brk + (PAGE_SIZE-1))) >> PAGE_SHIFT;
+ dump->u_dsize -= dump->u_tsize;
+ dump->u_ssize = 0;
+
+ if (dump->start_stack < TASK_SIZE)
+ dump->u_ssize = ((unsigned long) (TASK_SIZE - dump->start_stack)) >> PAGE_SHIFT;
+
+ dump->regs = *(struct user_context *) regs;
+#endif
+}
+
+/*
+ * sys_execve() executes a new program.
+ */
+asmlinkage int sys_execve(char *name, char **argv, char **envp)
+{
+ int error;
+ char * filename;
+
+ lock_kernel();
+ filename = getname(name);
+ error = PTR_ERR(filename);
+ if (IS_ERR(filename))
+ goto out;
+ error = do_execve(filename, argv, envp, __frame);
+ putname(filename);
+ out:
+ unlock_kernel();
+ return error;
+}
+
+unsigned long get_wchan(struct task_struct *p)
+{
+ struct pt_regs *regs0;
+ unsigned long fp, pc;
+ unsigned long stack_limit;
+ int count = 0;
+ if (!p || p == current || p->state == TASK_RUNNING)
+ return 0;
+
+ stack_limit = (unsigned long) (p + 1);
+ fp = p->thread.fp;
+ regs0 = p->thread.frame0;
+
+ do {
+ if (fp < stack_limit || fp >= (unsigned long) regs0 || fp & 3)
+ return 0;
+
+ pc = ((unsigned long *) fp)[2];
+
+ /* FIXME: This depends on the order of these functions. */
+ if (!in_sched_functions(pc))
+ return pc;
+
+ fp = *(unsigned long *) fp;
+ } while (count++ < 16);
+
+ return 0;
+}
+
+unsigned long thread_saved_pc(struct task_struct *tsk)
+{
+ /* Check whether the thread is blocked in resume() */
+ if (in_sched_functions(tsk->thread.pc))
+ return ((unsigned long *)tsk->thread.fp)[2];
+ else
+ return tsk->thread.pc;
+}
+
+int elf_check_arch(const struct elf32_hdr *hdr)
+{
+ unsigned long hsr0 = __get_HSR(0);
+ unsigned long psr = __get_PSR();
+
+ if (hdr->e_machine != EM_FRV)
+ return 0;
+
+ switch (hdr->e_flags & EF_FRV_GPR_MASK) {
+ case EF_FRV_GPR64:
+ if ((hsr0 & HSR0_GRN) == HSR0_GRN_32)
+ return 0;
+ case EF_FRV_GPR32:
+ case 0:
+ break;
+ default:
+ return 0;
+ }
+
+ switch (hdr->e_flags & EF_FRV_FPR_MASK) {
+ case EF_FRV_FPR64:
+ if ((hsr0 & HSR0_FRN) == HSR0_FRN_32)
+ return 0;
+ case EF_FRV_FPR32:
+ case EF_FRV_FPR_NONE:
+ case 0:
+ break;
+ default:
+ return 0;
+ }
+
+ if ((hdr->e_flags & EF_FRV_MULADD) == EF_FRV_MULADD)
+ if (PSR_IMPLE(psr) != PSR_IMPLE_FR405 &&
+ PSR_IMPLE(psr) != PSR_IMPLE_FR451)
+ return 0;
+
+ switch (hdr->e_flags & EF_FRV_CPU_MASK) {
+ case EF_FRV_CPU_GENERIC:
+ break;
+ case EF_FRV_CPU_FR300:
+ case EF_FRV_CPU_SIMPLE:
+ case EF_FRV_CPU_TOMCAT:
+ default:
+ return 0;
+ case EF_FRV_CPU_FR400:
+ if (PSR_IMPLE(psr) != PSR_IMPLE_FR401 &&
+ PSR_IMPLE(psr) != PSR_IMPLE_FR405 &&
+ PSR_IMPLE(psr) != PSR_IMPLE_FR451 &&
+ PSR_IMPLE(psr) != PSR_IMPLE_FR551)
+ return 0;
+ break;
+ case EF_FRV_CPU_FR450:
+ if (PSR_IMPLE(psr) != PSR_IMPLE_FR451)
+ return 0;
+ break;
+ case EF_FRV_CPU_FR500:
+ if (PSR_IMPLE(psr) != PSR_IMPLE_FR501)
+ return 0;
+ break;
+ case EF_FRV_CPU_FR550:
+ if (PSR_IMPLE(psr) != PSR_IMPLE_FR551)
+ return 0;
+ break;
+ }
+
+ return 1;
+}
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