diff options
Diffstat (limited to 'arch/sh/kernel/process_32.c')
| -rw-r--r-- | arch/sh/kernel/process_32.c | 197 |
1 files changed, 197 insertions, 0 deletions
diff --git a/arch/sh/kernel/process_32.c b/arch/sh/kernel/process_32.c new file mode 100644 index 000000000..92b6649d4 --- /dev/null +++ b/arch/sh/kernel/process_32.c @@ -0,0 +1,197 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * 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 - 2008 Paul Mundt + */ +#include <linux/module.h> +#include <linux/mm.h> +#include <linux/sched/debug.h> +#include <linux/sched/task.h> +#include <linux/sched/task_stack.h> +#include <linux/slab.h> +#include <linux/elfcore.h> +#include <linux/fs.h> +#include <linux/ftrace.h> +#include <linux/hw_breakpoint.h> +#include <linux/prefetch.h> +#include <linux/stackprotector.h> +#include <linux/uaccess.h> +#include <asm/mmu_context.h> +#include <asm/fpu.h> +#include <asm/syscalls.h> +#include <asm/switch_to.h> + +void show_regs(struct pt_regs * regs) +{ + pr_info("\n"); + show_regs_print_info(KERN_DEFAULT); + + pr_info("PC is at %pS\n", (void *)instruction_pointer(regs)); + pr_info("PR is at %pS\n", (void *)regs->pr); + + pr_info("PC : %08lx SP : %08lx SR : %08lx ", regs->pc, + regs->regs[15], regs->sr); +#ifdef CONFIG_MMU + pr_cont("TEA : %08x\n", __raw_readl(MMU_TEA)); +#else + pr_cont("\n"); +#endif + + pr_info("R0 : %08lx R1 : %08lx R2 : %08lx R3 : %08lx\n", + regs->regs[0], regs->regs[1], regs->regs[2], regs->regs[3]); + pr_info("R4 : %08lx R5 : %08lx R6 : %08lx R7 : %08lx\n", + regs->regs[4], regs->regs[5], regs->regs[6], regs->regs[7]); + pr_info("R8 : %08lx R9 : %08lx R10 : %08lx R11 : %08lx\n", + regs->regs[8], regs->regs[9], regs->regs[10], regs->regs[11]); + pr_info("R12 : %08lx R13 : %08lx R14 : %08lx\n", + regs->regs[12], regs->regs[13], regs->regs[14]); + pr_info("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, KERN_DEFAULT); + show_code(regs); +} + +void start_thread(struct pt_regs *regs, unsigned long new_pc, + unsigned long new_sp) +{ + regs->pr = 0; + regs->sr = SR_FD; + regs->pc = new_pc; + regs->regs[15] = new_sp; + + free_thread_xstate(current); +} +EXPORT_SYMBOL(start_thread); + +void flush_thread(void) +{ + struct task_struct *tsk = current; + + flush_ptrace_hw_breakpoint(tsk); + +#if defined(CONFIG_SH_FPU) + /* Forget lazy FPU state */ + clear_fpu(tsk, task_pt_regs(tsk)); + clear_used_math(); +#endif +} + +asmlinkage void ret_from_fork(void); +asmlinkage void ret_from_kernel_thread(void); + +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 thread_info *ti = task_thread_info(p); + struct pt_regs *childregs; + +#if defined(CONFIG_SH_DSP) + struct task_struct *tsk = current; + + if (is_dsp_enabled(tsk)) { + /* We can use the __save_dsp or just copy the struct: + * __save_dsp(p); + * p->thread.dsp_status.status |= SR_DSP + */ + p->thread.dsp_status = tsk->thread.dsp_status; + } +#endif + + memset(p->thread.ptrace_bps, 0, sizeof(p->thread.ptrace_bps)); + + childregs = task_pt_regs(p); + p->thread.sp = (unsigned long) childregs; + if (unlikely(args->fn)) { + memset(childregs, 0, sizeof(struct pt_regs)); + p->thread.pc = (unsigned long) ret_from_kernel_thread; + childregs->regs[4] = (unsigned long) args->fn_arg; + childregs->regs[5] = (unsigned long) args->fn; + childregs->sr = SR_MD; +#if defined(CONFIG_SH_FPU) + childregs->sr |= SR_FD; +#endif + ti->status &= ~TS_USEDFPU; + p->thread.fpu_counter = 0; + return 0; + } + *childregs = *current_pt_regs(); + + if (usp) + childregs->regs[15] = usp; + + if (clone_flags & CLONE_SETTLS) + childregs->gbr = tls; + + childregs->regs[0] = 0; /* Set return value for child */ + p->thread.pc = (unsigned long) ret_from_fork; + return 0; +} + +/* + * switch_to(x,y) should switch tasks from x to y. + * + */ +__notrace_funcgraph struct task_struct * +__switch_to(struct task_struct *prev, struct task_struct *next) +{ + struct thread_struct *next_t = &next->thread; + +#if defined(CONFIG_STACKPROTECTOR) && !defined(CONFIG_SMP) + __stack_chk_guard = next->stack_canary; +#endif + + unlazy_fpu(prev, task_pt_regs(prev)); + + /* we're going to use this soon, after a few expensive things */ + if (next->thread.fpu_counter > 5) + prefetch(next_t->xstate); + +#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 the task has used fpu the last 5 timeslices, just do a full + * restore of the math state immediately to avoid the trap; the + * chances of needing FPU soon are obviously high now + */ + if (next->thread.fpu_counter > 5) + __fpu_state_restore(); + + return prev; +} + +unsigned long __get_wchan(struct task_struct *p) +{ + unsigned long pc; + + /* + * 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; +} |