diff options
Diffstat (limited to 'arch/sparc/kernel/process_32.c')
-rw-r--r-- | arch/sparc/kernel/process_32.c | 413 |
1 files changed, 413 insertions, 0 deletions
diff --git a/arch/sparc/kernel/process_32.c b/arch/sparc/kernel/process_32.c new file mode 100644 index 000000000..0f9c606e1 --- /dev/null +++ b/arch/sparc/kernel/process_32.c @@ -0,0 +1,413 @@ +// SPDX-License-Identifier: GPL-2.0 +/* linux/arch/sparc/kernel/process.c + * + * Copyright (C) 1995, 2008 David S. Miller (davem@davemloft.net) + * Copyright (C) 1996 Eddie C. Dost (ecd@skynet.be) + */ + +/* + * This file handles the architecture-dependent parts of process handling.. + */ + +#include <stdarg.h> + +#include <linux/elfcore.h> +#include <linux/errno.h> +#include <linux/module.h> +#include <linux/sched.h> +#include <linux/sched/debug.h> +#include <linux/sched/task.h> +#include <linux/sched/task_stack.h> +#include <linux/kernel.h> +#include <linux/mm.h> +#include <linux/stddef.h> +#include <linux/ptrace.h> +#include <linux/user.h> +#include <linux/smp.h> +#include <linux/reboot.h> +#include <linux/delay.h> +#include <linux/pm.h> +#include <linux/slab.h> +#include <linux/cpu.h> + +#include <asm/auxio.h> +#include <asm/oplib.h> +#include <linux/uaccess.h> +#include <asm/page.h> +#include <asm/delay.h> +#include <asm/processor.h> +#include <asm/psr.h> +#include <asm/elf.h> +#include <asm/prom.h> +#include <asm/unistd.h> +#include <asm/setup.h> + +#include "kernel.h" + +/* + * Power management idle function + * Set in pm platform drivers (apc.c and pmc.c) + */ +void (*sparc_idle)(void); + +/* + * Power-off handler instantiation for pm.h compliance + * This is done via auxio, but could be used as a fallback + * handler when auxio is not present-- unused for now... + */ +void (*pm_power_off)(void) = machine_power_off; +EXPORT_SYMBOL(pm_power_off); + +/* + * sysctl - toggle power-off restriction for serial console + * systems in machine_power_off() + */ +int scons_pwroff = 1; + +extern void fpsave(unsigned long *, unsigned long *, void *, unsigned long *); + +struct task_struct *last_task_used_math = NULL; +struct thread_info *current_set[NR_CPUS]; + +/* Idle loop support. */ +void arch_cpu_idle(void) +{ + if (sparc_idle) + (*sparc_idle)(); + raw_local_irq_enable(); +} + +/* XXX cli/sti -> local_irq_xxx here, check this works once SMP is fixed. */ +void machine_halt(void) +{ + local_irq_enable(); + mdelay(8); + local_irq_disable(); + prom_halt(); + panic("Halt failed!"); +} + +void machine_restart(char * cmd) +{ + char *p; + + local_irq_enable(); + mdelay(8); + local_irq_disable(); + + p = strchr (reboot_command, '\n'); + if (p) *p = 0; + if (cmd) + prom_reboot(cmd); + if (*reboot_command) + prom_reboot(reboot_command); + prom_feval ("reset"); + panic("Reboot failed!"); +} + +void machine_power_off(void) +{ + if (auxio_power_register && + (!of_node_is_type(of_console_device, "serial") || scons_pwroff)) { + u8 power_register = sbus_readb(auxio_power_register); + power_register |= AUXIO_POWER_OFF; + sbus_writeb(power_register, auxio_power_register); + } + + machine_halt(); +} + +void show_regs(struct pt_regs *r) +{ + struct reg_window32 *rw = (struct reg_window32 *) r->u_regs[14]; + + show_regs_print_info(KERN_DEFAULT); + + printk("PSR: %08lx PC: %08lx NPC: %08lx Y: %08lx %s\n", + r->psr, r->pc, r->npc, r->y, print_tainted()); + printk("PC: <%pS>\n", (void *) r->pc); + printk("%%G: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n", + r->u_regs[0], r->u_regs[1], r->u_regs[2], r->u_regs[3], + r->u_regs[4], r->u_regs[5], r->u_regs[6], r->u_regs[7]); + printk("%%O: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n", + r->u_regs[8], r->u_regs[9], r->u_regs[10], r->u_regs[11], + r->u_regs[12], r->u_regs[13], r->u_regs[14], r->u_regs[15]); + printk("RPC: <%pS>\n", (void *) r->u_regs[15]); + + printk("%%L: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n", + rw->locals[0], rw->locals[1], rw->locals[2], rw->locals[3], + rw->locals[4], rw->locals[5], rw->locals[6], rw->locals[7]); + printk("%%I: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n", + rw->ins[0], rw->ins[1], rw->ins[2], rw->ins[3], + rw->ins[4], rw->ins[5], rw->ins[6], rw->ins[7]); +} + +/* + * The show_stack() is external API which we do not use ourselves. + * The oops is printed in die_if_kernel. + */ +void show_stack(struct task_struct *tsk, unsigned long *_ksp, const char *loglvl) +{ + unsigned long pc, fp; + unsigned long task_base; + struct reg_window32 *rw; + int count = 0; + + if (!tsk) + tsk = current; + + if (tsk == current && !_ksp) + __asm__ __volatile__("mov %%fp, %0" : "=r" (_ksp)); + + task_base = (unsigned long) task_stack_page(tsk); + fp = (unsigned long) _ksp; + do { + /* Bogus frame pointer? */ + if (fp < (task_base + sizeof(struct thread_info)) || + fp >= (task_base + (PAGE_SIZE << 1))) + break; + rw = (struct reg_window32 *) fp; + pc = rw->ins[7]; + printk("%s[%08lx : ", loglvl, pc); + printk("%s%pS ] ", loglvl, (void *) pc); + fp = rw->ins[6]; + } while (++count < 16); + printk("%s\n", loglvl); +} + +/* + * Free current thread data structures etc.. + */ +void exit_thread(struct task_struct *tsk) +{ +#ifndef CONFIG_SMP + if (last_task_used_math == tsk) { +#else + if (test_ti_thread_flag(task_thread_info(tsk), TIF_USEDFPU)) { +#endif + /* Keep process from leaving FPU in a bogon state. */ + put_psr(get_psr() | PSR_EF); + fpsave(&tsk->thread.float_regs[0], &tsk->thread.fsr, + &tsk->thread.fpqueue[0], &tsk->thread.fpqdepth); +#ifndef CONFIG_SMP + last_task_used_math = NULL; +#else + clear_ti_thread_flag(task_thread_info(tsk), TIF_USEDFPU); +#endif + } +} + +void flush_thread(void) +{ + current_thread_info()->w_saved = 0; + +#ifndef CONFIG_SMP + if(last_task_used_math == current) { +#else + if (test_thread_flag(TIF_USEDFPU)) { +#endif + /* Clean the fpu. */ + put_psr(get_psr() | PSR_EF); + fpsave(¤t->thread.float_regs[0], ¤t->thread.fsr, + ¤t->thread.fpqueue[0], ¤t->thread.fpqdepth); +#ifndef CONFIG_SMP + last_task_used_math = NULL; +#else + clear_thread_flag(TIF_USEDFPU); +#endif + } + + /* This task is no longer a kernel thread. */ + if (current->thread.flags & SPARC_FLAG_KTHREAD) { + current->thread.flags &= ~SPARC_FLAG_KTHREAD; + + /* We must fixup kregs as well. */ + /* XXX This was not fixed for ti for a while, worked. Unused? */ + current->thread.kregs = (struct pt_regs *) + (task_stack_page(current) + (THREAD_SIZE - TRACEREG_SZ)); + } +} + +static inline struct sparc_stackf __user * +clone_stackframe(struct sparc_stackf __user *dst, + struct sparc_stackf __user *src) +{ + unsigned long size, fp; + struct sparc_stackf *tmp; + struct sparc_stackf __user *sp; + + if (get_user(tmp, &src->fp)) + return NULL; + + fp = (unsigned long) tmp; + size = (fp - ((unsigned long) src)); + fp = (unsigned long) dst; + sp = (struct sparc_stackf __user *)(fp - size); + + /* do_fork() grabs the parent semaphore, we must release it + * temporarily so we can build the child clone stack frame + * without deadlocking. + */ + if (__copy_user(sp, src, size)) + sp = NULL; + else if (put_user(fp, &sp->fp)) + sp = NULL; + + return sp; +} + +/* Copy a Sparc thread. The fork() return value conventions + * under SunOS are nothing short of bletcherous: + * Parent --> %o0 == childs pid, %o1 == 0 + * Child --> %o0 == parents pid, %o1 == 1 + * + * NOTE: We have a separate fork kpsr/kwim because + * the parent could change these values between + * sys_fork invocation and when we reach here + * if the parent should sleep while trying to + * allocate the task_struct and kernel stack in + * do_fork(). + * XXX See comment above sys_vfork in sparc64. todo. + */ +extern void ret_from_fork(void); +extern void ret_from_kernel_thread(void); + +int copy_thread(unsigned long clone_flags, unsigned long sp, unsigned long arg, + struct task_struct *p, unsigned long tls) +{ + struct thread_info *ti = task_thread_info(p); + struct pt_regs *childregs, *regs = current_pt_regs(); + char *new_stack; + +#ifndef CONFIG_SMP + if(last_task_used_math == current) { +#else + if (test_thread_flag(TIF_USEDFPU)) { +#endif + put_psr(get_psr() | PSR_EF); + fpsave(&p->thread.float_regs[0], &p->thread.fsr, + &p->thread.fpqueue[0], &p->thread.fpqdepth); + } + + /* + * p->thread_info new_stack childregs stack bottom + * ! ! ! ! + * V V (stk.fr.) V (pt_regs) V + * +----- - - - - - ------+===========+=============+ + */ + new_stack = task_stack_page(p) + THREAD_SIZE; + new_stack -= STACKFRAME_SZ + TRACEREG_SZ; + childregs = (struct pt_regs *) (new_stack + STACKFRAME_SZ); + + /* + * A new process must start with interrupts disabled, see schedule_tail() + * and finish_task_switch(). (If we do not do it and if a timer interrupt + * hits before we unlock and attempts to take the rq->lock, we deadlock.) + * + * Thus, kpsr |= PSR_PIL. + */ + ti->ksp = (unsigned long) new_stack; + p->thread.kregs = childregs; + + if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) { + extern int nwindows; + unsigned long psr; + memset(new_stack, 0, STACKFRAME_SZ + TRACEREG_SZ); + p->thread.flags |= SPARC_FLAG_KTHREAD; + p->thread.current_ds = KERNEL_DS; + ti->kpc = (((unsigned long) ret_from_kernel_thread) - 0x8); + childregs->u_regs[UREG_G1] = sp; /* function */ + childregs->u_regs[UREG_G2] = arg; + psr = childregs->psr = get_psr(); + ti->kpsr = psr | PSR_PIL; + ti->kwim = 1 << (((psr & PSR_CWP) + 1) % nwindows); + return 0; + } + memcpy(new_stack, (char *)regs - STACKFRAME_SZ, STACKFRAME_SZ + TRACEREG_SZ); + childregs->u_regs[UREG_FP] = sp; + p->thread.flags &= ~SPARC_FLAG_KTHREAD; + p->thread.current_ds = USER_DS; + ti->kpc = (((unsigned long) ret_from_fork) - 0x8); + ti->kpsr = current->thread.fork_kpsr | PSR_PIL; + ti->kwim = current->thread.fork_kwim; + + if (sp != regs->u_regs[UREG_FP]) { + struct sparc_stackf __user *childstack; + struct sparc_stackf __user *parentstack; + + /* + * This is a clone() call with supplied user stack. + * Set some valid stack frames to give to the child. + */ + childstack = (struct sparc_stackf __user *) + (sp & ~0xfUL); + parentstack = (struct sparc_stackf __user *) + regs->u_regs[UREG_FP]; + +#if 0 + printk("clone: parent stack:\n"); + show_stackframe(parentstack); +#endif + + childstack = clone_stackframe(childstack, parentstack); + if (!childstack) + return -EFAULT; + +#if 0 + printk("clone: child stack:\n"); + show_stackframe(childstack); +#endif + + childregs->u_regs[UREG_FP] = (unsigned long)childstack; + } + +#ifdef CONFIG_SMP + /* FPU must be disabled on SMP. */ + childregs->psr &= ~PSR_EF; + clear_tsk_thread_flag(p, TIF_USEDFPU); +#endif + + /* Set the return value for the child. */ + childregs->u_regs[UREG_I0] = current->pid; + childregs->u_regs[UREG_I1] = 1; + + /* Set the return value for the parent. */ + regs->u_regs[UREG_I1] = 0; + + if (clone_flags & CLONE_SETTLS) + childregs->u_regs[UREG_G7] = tls; + + return 0; +} + +unsigned long get_wchan(struct task_struct *task) +{ + unsigned long pc, fp, bias = 0; + unsigned long task_base = (unsigned long) task; + unsigned long ret = 0; + struct reg_window32 *rw; + int count = 0; + + if (!task || task == current || + task->state == TASK_RUNNING) + goto out; + + fp = task_thread_info(task)->ksp + bias; + do { + /* Bogus frame pointer? */ + if (fp < (task_base + sizeof(struct thread_info)) || + fp >= (task_base + (2 * PAGE_SIZE))) + break; + rw = (struct reg_window32 *) fp; + pc = rw->ins[7]; + if (!in_sched_functions(pc)) { + ret = pc; + goto out; + } + fp = rw->ins[6] + bias; + } while (++count < 16); + +out: + return ret; +} + |