From ace9429bb58fd418f0c81d4c2835699bddf6bde6 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Thu, 11 Apr 2024 10:27:49 +0200 Subject: Adding upstream version 6.6.15. Signed-off-by: Daniel Baumann --- arch/m68k/kernel/process.c | 285 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 285 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 0000000000..e06ce147c0 --- /dev/null +++ b/arch/m68k/kernel/process.c @@ -0,0 +1,285 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * 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 +#include + +#include +#include +#include + + +asmlinkage void ret_from_fork(void); +asmlinkage void ret_from_kernel_thread(void); + +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) +{ + do_kernel_power_off(); + for (;;); +} + +void (*pm_power_off)(void); +EXPORT_SYMBOL(pm_power_off); + +void show_regs(struct pt_regs * regs) +{ + pr_info("Format %02x Vector: %04x PC: %08lx Status: %04x %s\n", + regs->format, regs->vector, regs->pc, regs->sr, + print_tainted()); + pr_info("ORIG_D0: %08lx D0: %08lx A2: %08lx A1: %08lx\n", + regs->orig_d0, regs->d0, regs->a2, regs->a1); + pr_info("A0: %08lx D5: %08lx D4: %08lx\n", regs->a0, regs->d5, + regs->d4); + pr_info("D3: %08lx D2: %08lx D1: %08lx\n", regs->d3, regs->d2, + regs->d1); + if (!(regs->sr & PS_S)) + pr_info("USP: %08lx\n", rdusp()); +} + +void flush_thread(void) +{ + current->thread.fc = USER_DATA; +#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 + * kernel_clone() anyway. So in this case it's actually better to pass pt_regs * + * and extract arguments for kernel_clone() from there. Eventually we might + * go for calling kernel_clone() directly from the wrapper, but only after we + * are finished with kernel_clone() prototype conversion. + */ +asmlinkage int m68k_clone(struct pt_regs *regs) +{ + /* regs will be equal to current_pt_regs() */ + struct kernel_clone_args args = { + .flags = regs->d1 & ~CSIGNAL, + .pidfd = (int __user *)regs->d3, + .child_tid = (int __user *)regs->d4, + .parent_tid = (int __user *)regs->d3, + .exit_signal = regs->d1 & CSIGNAL, + .stack = regs->d2, + .tls = regs->d5, + }; + + return kernel_clone(&args); +} + +/* + * Because extra registers are saved on the stack after the sys_clone3() + * arguments, this C wrapper extracts them from pt_regs * and then calls the + * generic sys_clone3() implementation. + */ +asmlinkage int m68k_clone3(struct pt_regs *regs) +{ + return sys_clone3((struct clone_args __user *)regs->d1, regs->d2); +} + +int copy_thread(struct task_struct *p, const struct kernel_clone_args *args) +{ + unsigned long clone_flags = args->flags; + unsigned long usp = args->stack; + unsigned long tls = args->tls; + 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.fc = USER_DATA; + + if (unlikely(args->fn)) { + /* kernel thread */ + memset(frame, 0, sizeof(struct fork_frame)); + frame->regs.sr = PS_S; + frame->sw.a3 = (unsigned long)args->fn; + frame->sw.d7 = (unsigned long)args->fn_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 = tls; + +#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. */ +int elf_core_copy_task_fpregs(struct task_struct *t, elf_fpregset_t *fpu) +{ + 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; + } + + if (IS_ENABLED(CONFIG_FPU)) { + char fpustate[216]; + + /* 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; +} + +unsigned long __get_wchan(struct task_struct *p) +{ + unsigned long fp, pc; + unsigned long stack_page; + int count = 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