diff options
Diffstat (limited to 'arch/sh/kernel/process_32.c')
-rw-r--r-- | arch/sh/kernel/process_32.c | 465 |
1 files changed, 465 insertions, 0 deletions
diff --git a/arch/sh/kernel/process_32.c b/arch/sh/kernel/process_32.c new file mode 100644 index 00000000000..9ab1926b9d1 --- /dev/null +++ b/arch/sh/kernel/process_32.c @@ -0,0 +1,465 @@ +/* + * arch/sh/kernel/process.c + * + * This file handles the architecture-dependent parts of process handling.. + * + * Copyright (C) 1995 Linus Torvalds + * + * SuperH version: Copyright (C) 1999, 2000 Niibe Yutaka & Kaz Kojima + * Copyright (C) 2006 Lineo Solutions Inc. support SH4A UBC + * Copyright (C) 2002 - 2007 Paul Mundt + */ +#include <linux/module.h> +#include <linux/mm.h> +#include <linux/elfcore.h> +#include <linux/pm.h> +#include <linux/kallsyms.h> +#include <linux/kexec.h> +#include <linux/kdebug.h> +#include <linux/tick.h> +#include <linux/reboot.h> +#include <linux/fs.h> +#include <linux/preempt.h> +#include <asm/uaccess.h> +#include <asm/mmu_context.h> +#include <asm/pgalloc.h> +#include <asm/system.h> +#include <asm/ubc.h> + +static int hlt_counter; +int ubc_usercnt = 0; + +void (*pm_idle)(void); +void (*pm_power_off)(void); +EXPORT_SYMBOL(pm_power_off); + +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; +} +__setup("nohlt", nohlt_setup); + +static int __init hlt_setup(char *__unused) +{ + hlt_counter = 0; + return 1; +} +__setup("hlt", hlt_setup); + +void default_idle(void) +{ + if (!hlt_counter) { + clear_thread_flag(TIF_POLLING_NRFLAG); + smp_mb__after_clear_bit(); + set_bl_bit(); + while (!need_resched()) + cpu_sleep(); + clear_bl_bit(); + set_thread_flag(TIF_POLLING_NRFLAG); + } else + while (!need_resched()) + cpu_relax(); +} + +void cpu_idle(void) +{ + set_thread_flag(TIF_POLLING_NRFLAG); + + /* endless idle loop with no priority at all */ + while (1) { + void (*idle)(void) = pm_idle; + + if (!idle) + idle = default_idle; + + tick_nohz_stop_sched_tick(); + while (!need_resched()) + idle(); + tick_nohz_restart_sched_tick(); + + preempt_enable_no_resched(); + schedule(); + preempt_disable(); + check_pgt_cache(); + } +} + +void machine_restart(char * __unused) +{ + /* SR.BL=1 and invoke address error to let CPU reset (manual reset) */ + asm volatile("ldc %0, sr\n\t" + "mov.l @%1, %0" : : "r" (0x10000000), "r" (0x80000001)); +} + +void machine_halt(void) +{ + local_irq_disable(); + + while (1) + cpu_sleep(); +} + +void machine_power_off(void) +{ + if (pm_power_off) + pm_power_off(); +} + +void show_regs(struct pt_regs * regs) +{ + printk("\n"); + printk("Pid : %d, Comm: %20s\n", task_pid_nr(current), current->comm); + print_symbol("PC is at %s\n", instruction_pointer(regs)); + printk("PC : %08lx SP : %08lx SR : %08lx ", + regs->pc, regs->regs[15], regs->sr); +#ifdef CONFIG_MMU + printk("TEA : %08x ", ctrl_inl(MMU_TEA)); +#else + printk(" "); +#endif + printk("%s\n", print_tainted()); + + printk("R0 : %08lx R1 : %08lx R2 : %08lx R3 : %08lx\n", + regs->regs[0],regs->regs[1], + regs->regs[2],regs->regs[3]); + printk("R4 : %08lx R5 : %08lx R6 : %08lx R7 : %08lx\n", + regs->regs[4],regs->regs[5], + regs->regs[6],regs->regs[7]); + printk("R8 : %08lx R9 : %08lx R10 : %08lx R11 : %08lx\n", + regs->regs[8],regs->regs[9], + regs->regs[10],regs->regs[11]); + printk("R12 : %08lx R13 : %08lx R14 : %08lx\n", + regs->regs[12],regs->regs[13], + regs->regs[14]); + printk("MACH: %08lx MACL: %08lx GBR : %08lx PR : %08lx\n", + regs->mach, regs->macl, regs->gbr, regs->pr); + + show_trace(NULL, (unsigned long *)regs->regs[15], regs); +} + +/* + * Create a kernel thread + */ + +/* + * This is the mechanism for creating a new kernel thread. + * + */ +extern void kernel_thread_helper(void); +__asm__(".align 5\n" + "kernel_thread_helper:\n\t" + "jsr @r5\n\t" + " nop\n\t" + "mov.l 1f, r1\n\t" + "jsr @r1\n\t" + " mov r0, r4\n\t" + ".align 2\n\t" + "1:.long do_exit"); + +/* Don't use this in BL=1(cli). Or else, CPU resets! */ +int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags) +{ + struct pt_regs regs; + + memset(®s, 0, sizeof(regs)); + regs.regs[4] = (unsigned long)arg; + regs.regs[5] = (unsigned long)fn; + + regs.pc = (unsigned long)kernel_thread_helper; + regs.sr = (1 << 30); + + /* Ok, create the new process.. */ + return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0, + ®s, 0, NULL, NULL); +} + +/* + * Free current thread data structures etc.. + */ +void exit_thread(void) +{ + if (current->thread.ubc_pc) { + current->thread.ubc_pc = 0; + ubc_usercnt -= 1; + } +} + +void flush_thread(void) +{ +#if defined(CONFIG_SH_FPU) + struct task_struct *tsk = current; + /* Forget lazy FPU state */ + clear_fpu(tsk, task_pt_regs(tsk)); + clear_used_math(); +#endif +} + +void release_thread(struct task_struct *dead_task) +{ + /* do nothing */ +} + +/* Fill in the fpu structure for a core dump.. */ +int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu) +{ + int fpvalid = 0; + +#if defined(CONFIG_SH_FPU) + struct task_struct *tsk = current; + + fpvalid = !!tsk_used_math(tsk); + if (fpvalid) { + unlazy_fpu(tsk, regs); + memcpy(fpu, &tsk->thread.fpu.hard, sizeof(*fpu)); + } +#endif + + return fpvalid; +} + +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 thread_info *ti = task_thread_info(p); + struct pt_regs *childregs; +#if defined(CONFIG_SH_FPU) + struct task_struct *tsk = current; + + unlazy_fpu(tsk, regs); + p->thread.fpu = tsk->thread.fpu; + copy_to_stopped_child_used_math(p); +#endif + + childregs = task_pt_regs(p); + *childregs = *regs; + + if (user_mode(regs)) { + childregs->regs[15] = usp; + ti->addr_limit = USER_DS; + } else { + childregs->regs[15] = (unsigned long)childregs; + ti->addr_limit = KERNEL_DS; + } + + if (clone_flags & CLONE_SETTLS) + childregs->gbr = childregs->regs[0]; + + childregs->regs[0] = 0; /* Set return value for child */ + + p->thread.sp = (unsigned long) childregs; + p->thread.pc = (unsigned long) ret_from_fork; + + p->thread.ubc_pc = 0; + + return 0; +} + +/* Tracing by user break controller. */ +static void ubc_set_tracing(int asid, unsigned long pc) +{ +#if defined(CONFIG_CPU_SH4A) + unsigned long val; + + val = (UBC_CBR_ID_INST | UBC_CBR_RW_READ | UBC_CBR_CE); + val |= (UBC_CBR_AIE | UBC_CBR_AIV_SET(asid)); + + ctrl_outl(val, UBC_CBR0); + ctrl_outl(pc, UBC_CAR0); + ctrl_outl(0x0, UBC_CAMR0); + ctrl_outl(0x0, UBC_CBCR); + + val = (UBC_CRR_RES | UBC_CRR_PCB | UBC_CRR_BIE); + ctrl_outl(val, UBC_CRR0); + + /* Read UBC register that we wrote last, for checking update */ + val = ctrl_inl(UBC_CRR0); + +#else /* CONFIG_CPU_SH4A */ + ctrl_outl(pc, UBC_BARA); + +#ifdef CONFIG_MMU + ctrl_outb(asid, UBC_BASRA); +#endif + + ctrl_outl(0, UBC_BAMRA); + + if (current_cpu_data.type == CPU_SH7729 || + current_cpu_data.type == CPU_SH7710 || + current_cpu_data.type == CPU_SH7712) { + ctrl_outw(BBR_INST | BBR_READ | BBR_CPU, UBC_BBRA); + ctrl_outl(BRCR_PCBA | BRCR_PCTE, UBC_BRCR); + } else { + ctrl_outw(BBR_INST | BBR_READ, UBC_BBRA); + ctrl_outw(BRCR_PCBA, UBC_BRCR); + } +#endif /* CONFIG_CPU_SH4A */ +} + +/* + * switch_to(x,y) should switch tasks from x to y. + * + */ +struct task_struct *__switch_to(struct task_struct *prev, + struct task_struct *next) +{ +#if defined(CONFIG_SH_FPU) + unlazy_fpu(prev, task_pt_regs(prev)); +#endif + +#ifdef CONFIG_MMU + /* + * Restore the kernel mode register + * k7 (r7_bank1) + */ + asm volatile("ldc %0, r7_bank" + : /* no output */ + : "r" (task_thread_info(next))); +#endif + + /* If no tasks are using the UBC, we're done */ + if (ubc_usercnt == 0) + /* If no tasks are using the UBC, we're done */; + else if (next->thread.ubc_pc && next->mm) { + int asid = 0; +#ifdef CONFIG_MMU + asid |= cpu_asid(smp_processor_id(), next->mm); +#endif + ubc_set_tracing(asid, next->thread.ubc_pc); + } else { +#if defined(CONFIG_CPU_SH4A) + ctrl_outl(UBC_CBR_INIT, UBC_CBR0); + ctrl_outl(UBC_CRR_INIT, UBC_CRR0); +#else + ctrl_outw(0, UBC_BBRA); + ctrl_outw(0, UBC_BBRB); +#endif + } + + return prev; +} + +asmlinkage int sys_fork(unsigned long r4, unsigned long r5, + unsigned long r6, unsigned long r7, + struct pt_regs __regs) +{ +#ifdef CONFIG_MMU + struct pt_regs *regs = RELOC_HIDE(&__regs, 0); + return do_fork(SIGCHLD, regs->regs[15], regs, 0, NULL, NULL); +#else + /* fork almost works, enough to trick you into looking elsewhere :-( */ + return -EINVAL; +#endif +} + +asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp, + unsigned long parent_tidptr, + unsigned long child_tidptr, + struct pt_regs __regs) +{ + struct pt_regs *regs = RELOC_HIDE(&__regs, 0); + if (!newsp) + newsp = regs->regs[15]; + return do_fork(clone_flags, newsp, regs, 0, + (int __user *)parent_tidptr, + (int __user *)child_tidptr); +} + +/* + * This is trivial, and on the face of it looks like it + * could equally well be done in user mode. + * + * Not so, for quite unobvious reasons - register pressure. + * In user mode vfork() cannot have a stack frame, and if + * done by calling the "clone()" system call directly, you + * do not have enough call-clobbered registers to hold all + * the information you need. + */ +asmlinkage int sys_vfork(unsigned long r4, unsigned long r5, + unsigned long r6, unsigned long r7, + struct pt_regs __regs) +{ + struct pt_regs *regs = RELOC_HIDE(&__regs, 0); + return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->regs[15], regs, + 0, NULL, NULL); +} + +/* + * sys_execve() executes a new program. + */ +asmlinkage int sys_execve(char __user *ufilename, char __user * __user *uargv, + char __user * __user *uenvp, unsigned long r7, + struct pt_regs __regs) +{ + struct pt_regs *regs = RELOC_HIDE(&__regs, 0); + int error; + char *filename; + + filename = getname(ufilename); + error = PTR_ERR(filename); + if (IS_ERR(filename)) + goto out; + + error = do_execve(filename, uargv, uenvp, regs); + if (error == 0) { + task_lock(current); + current->ptrace &= ~PT_DTRACE; + task_unlock(current); + } + putname(filename); +out: + return error; +} + +unsigned long get_wchan(struct task_struct *p) +{ + unsigned long pc; + + if (!p || p == current || p->state == TASK_RUNNING) + return 0; + + /* + * The same comment as on the Alpha applies here, too ... + */ + pc = thread_saved_pc(p); + +#ifdef CONFIG_FRAME_POINTER + if (in_sched_functions(pc)) { + unsigned long schedule_frame = (unsigned long)p->thread.sp; + return ((unsigned long *)schedule_frame)[21]; + } +#endif + + return pc; +} + +asmlinkage void break_point_trap(void) +{ + /* Clear tracing. */ +#if defined(CONFIG_CPU_SH4A) + ctrl_outl(UBC_CBR_INIT, UBC_CBR0); + ctrl_outl(UBC_CRR_INIT, UBC_CRR0); +#else + ctrl_outw(0, UBC_BBRA); + ctrl_outw(0, UBC_BBRB); +#endif + current->thread.ubc_pc = 0; + ubc_usercnt -= 1; + + force_sig(SIGTRAP, current); +} |