diff options
Diffstat (limited to 'arch/frv/kernel/process.c')
| -rw-r--r-- | arch/frv/kernel/process.c | 381 |
1 files changed, 381 insertions, 0 deletions
diff --git a/arch/frv/kernel/process.c b/arch/frv/kernel/process.c new file mode 100644 index 00000000..9d359752 --- /dev/null +++ b/arch/frv/kernel/process.c @@ -0,0 +1,381 @@ +/* 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/module.h> +#include <linux/errno.h> +#include <linux/sched.h> +#include <linux/kernel.h> +#include <linux/mm.h> +#include <linux/smp.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 <linux/pagemap.h> + +#include <asm/asm-offsets.h> +#include <asm/uaccess.h> +#include <asm/system.h> +#include <asm/setup.h> +#include <asm/pgtable.h> +#include <asm/tlb.h> +#include <asm/gdb-stub.h> +#include <asm/mb-regs.h> + +#include "local.h" + +asmlinkage void ret_from_fork(void); + +#include <asm/pgalloc.h> + +void (*pm_power_off)(void); +EXPORT_SYMBOL(pm_power_off); + +struct task_struct *alloc_task_struct_node(int node) +{ + struct task_struct *p = kmalloc_node(THREAD_SIZE, GFP_KERNEL, node); + + 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()) { + check_pgt_cache(); + + if (!frv_dma_inprogress && idle) + idle(); + } + + preempt_enable_no_resched(); + schedule(); + preempt_disable(); + } +} + +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(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 *) + (task_stack_page(p) + THREAD_SIZE - FRV_FRAME0_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) task_thread_info(p); + 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() */ + +/* + * sys_execve() executes a new program. + */ +asmlinkage int sys_execve(const char __user *name, + const char __user *const __user *argv, + const char __user *const __user *envp) +{ + int error; + char * filename; + + filename = getname(name); + error = PTR_ERR(filename); + if (IS_ERR(filename)) + return error; + error = do_execve(filename, argv, envp, __frame); + putname(filename); + 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; +} + +int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpregs) +{ + memcpy(fpregs, + ¤t->thread.user->f, + sizeof(current->thread.user->f)); + return 1; +} |