From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- arch/m68k/kernel/process.c | 277 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 277 insertions(+) create mode 100644 arch/m68k/kernel/process.c (limited to 'arch/m68k/kernel/process.c') diff --git a/arch/m68k/kernel/process.c b/arch/m68k/kernel/process.c new file mode 100644 index 000000000..c55ff719f --- /dev/null +++ b/arch/m68k/kernel/process.c @@ -0,0 +1,277 @@ +/* + * linux/arch/m68k/kernel/process.c + * + * Copyright (C) 1995 Hamish Macdonald + * + * 68060 fixes by Jesper Skov + */ + +/* + * This file handles the architecture-dependent parts of process handling.. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include +#include + + +asmlinkage void ret_from_fork(void); +asmlinkage void ret_from_kernel_thread(void); + + +/* + * Return saved PC from a blocked thread + */ +unsigned long thread_saved_pc(struct task_struct *tsk) +{ + struct switch_stack *sw = (struct switch_stack *)tsk->thread.ksp; + /* Check whether the thread is blocked in resume() */ + if (in_sched_functions(sw->retpc)) + return ((unsigned long *)sw->a6)[1]; + else + return sw->retpc; +} + +void arch_cpu_idle(void) +{ +#if defined(MACH_ATARI_ONLY) + /* block out HSYNC on the atari (falcon) */ + __asm__("stop #0x2200" : : : "cc"); +#else + __asm__("stop #0x2000" : : : "cc"); +#endif +} + +void machine_restart(char * __unused) +{ + if (mach_reset) + mach_reset(); + for (;;); +} + +void machine_halt(void) +{ + if (mach_halt) + mach_halt(); + for (;;); +} + +void machine_power_off(void) +{ + if (mach_power_off) + mach_power_off(); + for (;;); +} + +void (*pm_power_off)(void) = machine_power_off; +EXPORT_SYMBOL(pm_power_off); + +void show_regs(struct pt_regs * regs) +{ + printk("\n"); + printk("Format %02x Vector: %04x PC: %08lx Status: %04x %s\n", + regs->format, regs->vector, regs->pc, regs->sr, print_tainted()); + printk("ORIG_D0: %08lx D0: %08lx A2: %08lx A1: %08lx\n", + regs->orig_d0, regs->d0, regs->a2, regs->a1); + printk("A0: %08lx D5: %08lx D4: %08lx\n", + regs->a0, regs->d5, regs->d4); + printk("D3: %08lx D2: %08lx D1: %08lx\n", + regs->d3, regs->d2, regs->d1); + if (!(regs->sr & PS_S)) + printk("USP: %08lx\n", rdusp()); +} + +void flush_thread(void) +{ + current->thread.fs = __USER_DS; +#ifdef CONFIG_FPU + if (!FPU_IS_EMU) { + unsigned long zero = 0; + asm volatile("frestore %0": :"m" (zero)); + } +#endif +} + +/* + * Why not generic sys_clone, you ask? m68k passes all arguments on stack. + * And we need all registers saved, which means a bunch of stuff pushed + * on top of pt_regs, which means that sys_clone() arguments would be + * buried. We could, of course, copy them, but it's too costly for no + * good reason - generic clone() would have to copy them *again* for + * do_fork() anyway. So in this case it's actually better to pass pt_regs * + * and extract arguments for do_fork() from there. Eventually we might + * go for calling do_fork() directly from the wrapper, but only after we + * are finished with do_fork() prototype conversion. + */ +asmlinkage int m68k_clone(struct pt_regs *regs) +{ + /* regs will be equal to current_pt_regs() */ + return do_fork(regs->d1, regs->d2, 0, + (int __user *)regs->d3, (int __user *)regs->d4); +} + +int copy_thread(unsigned long clone_flags, unsigned long usp, + unsigned long arg, struct task_struct *p) +{ + struct fork_frame { + struct switch_stack sw; + struct pt_regs regs; + } *frame; + + frame = (struct fork_frame *) (task_stack_page(p) + THREAD_SIZE) - 1; + + p->thread.ksp = (unsigned long)frame; + p->thread.esp0 = (unsigned long)&frame->regs; + + /* + * Must save the current SFC/DFC value, NOT the value when + * the parent was last descheduled - RGH 10-08-96 + */ + p->thread.fs = get_fs().seg; + + if (unlikely(p->flags & PF_KTHREAD)) { + /* kernel thread */ + memset(frame, 0, sizeof(struct fork_frame)); + frame->regs.sr = PS_S; + frame->sw.a3 = usp; /* function */ + frame->sw.d7 = arg; + frame->sw.retpc = (unsigned long)ret_from_kernel_thread; + p->thread.usp = 0; + return 0; + } + memcpy(frame, container_of(current_pt_regs(), struct fork_frame, regs), + sizeof(struct fork_frame)); + frame->regs.d0 = 0; + frame->sw.retpc = (unsigned long)ret_from_fork; + p->thread.usp = usp ?: rdusp(); + + if (clone_flags & CLONE_SETTLS) + task_thread_info(p)->tp_value = frame->regs.d5; + +#ifdef CONFIG_FPU + if (!FPU_IS_EMU) { + /* Copy the current fpu state */ + asm volatile ("fsave %0" : : "m" (p->thread.fpstate[0]) : "memory"); + + if (!CPU_IS_060 ? p->thread.fpstate[0] : p->thread.fpstate[2]) { + if (CPU_IS_COLDFIRE) { + asm volatile ("fmovemd %/fp0-%/fp7,%0\n\t" + "fmovel %/fpiar,%1\n\t" + "fmovel %/fpcr,%2\n\t" + "fmovel %/fpsr,%3" + : + : "m" (p->thread.fp[0]), + "m" (p->thread.fpcntl[0]), + "m" (p->thread.fpcntl[1]), + "m" (p->thread.fpcntl[2]) + : "memory"); + } else { + asm volatile ("fmovemx %/fp0-%/fp7,%0\n\t" + "fmoveml %/fpiar/%/fpcr/%/fpsr,%1" + : + : "m" (p->thread.fp[0]), + "m" (p->thread.fpcntl[0]) + : "memory"); + } + } + + /* Restore the state in case the fpu was busy */ + asm volatile ("frestore %0" : : "m" (p->thread.fpstate[0])); + } +#endif /* CONFIG_FPU */ + + return 0; +} + +/* Fill in the fpu structure for a core dump. */ +#ifdef CONFIG_FPU +int dump_fpu (struct pt_regs *regs, struct user_m68kfp_struct *fpu) +{ + char fpustate[216]; + + if (FPU_IS_EMU) { + int i; + + memcpy(fpu->fpcntl, current->thread.fpcntl, 12); + memcpy(fpu->fpregs, current->thread.fp, 96); + /* Convert internal fpu reg representation + * into long double format + */ + for (i = 0; i < 24; i += 3) + fpu->fpregs[i] = ((fpu->fpregs[i] & 0xffff0000) << 15) | + ((fpu->fpregs[i] & 0x0000ffff) << 16); + return 1; + } + + /* First dump the fpu context to avoid protocol violation. */ + asm volatile ("fsave %0" :: "m" (fpustate[0]) : "memory"); + if (!CPU_IS_060 ? !fpustate[0] : !fpustate[2]) + return 0; + + if (CPU_IS_COLDFIRE) { + asm volatile ("fmovel %/fpiar,%0\n\t" + "fmovel %/fpcr,%1\n\t" + "fmovel %/fpsr,%2\n\t" + "fmovemd %/fp0-%/fp7,%3" + : + : "m" (fpu->fpcntl[0]), + "m" (fpu->fpcntl[1]), + "m" (fpu->fpcntl[2]), + "m" (fpu->fpregs[0]) + : "memory"); + } else { + asm volatile ("fmovem %/fpiar/%/fpcr/%/fpsr,%0" + : + : "m" (fpu->fpcntl[0]) + : "memory"); + asm volatile ("fmovemx %/fp0-%/fp7,%0" + : + : "m" (fpu->fpregs[0]) + : "memory"); + } + + return 1; +} +EXPORT_SYMBOL(dump_fpu); +#endif /* CONFIG_FPU */ + +unsigned long get_wchan(struct task_struct *p) +{ + unsigned long fp, pc; + unsigned long stack_page; + int count = 0; + if (!p || p == current || p->state == TASK_RUNNING) + return 0; + + stack_page = (unsigned long)task_stack_page(p); + fp = ((struct switch_stack *)p->thread.ksp)->a6; + do { + if (fp < stack_page+sizeof(struct thread_info) || + fp >= 8184+stack_page) + return 0; + pc = ((unsigned long *)fp)[1]; + if (!in_sched_functions(pc)) + return pc; + fp = *(unsigned long *) fp; + } while (count++ < 16); + return 0; +} -- cgit v1.2.3-54-g00ecf