/* * include/asm-m68k/processor.h * * Copyright (C) 1995 Hamish Macdonald */ #ifndef __ASM_M68K_PROCESSOR_H #define __ASM_M68K_PROCESSOR_H /* * Default implementation of macro that returns current * instruction pointer ("program counter"). */ #define current_text_addr() ({ __label__ _l; _l: &&_l;}) #include <linux/thread_info.h> #include <asm/segment.h> #include <asm/fpu.h> #include <asm/ptrace.h> static inline unsigned long rdusp(void) { unsigned long usp; __asm__ __volatile__("move %/usp,%0" : "=a" (usp)); return usp; } static inline void wrusp(unsigned long usp) { __asm__ __volatile__("move %0,%/usp" : : "a" (usp)); } /* * User space process size: 3.75GB. This is hardcoded into a few places, * so don't change it unless you know what you are doing. */ #ifndef CONFIG_SUN3 #define TASK_SIZE (0xF0000000UL) #else #define TASK_SIZE (0x0E000000UL) #endif #ifdef __KERNEL__ #define STACK_TOP TASK_SIZE #define STACK_TOP_MAX STACK_TOP #endif /* This decides where the kernel will search for a free chunk of vm * space during mmap's. */ #ifndef CONFIG_SUN3 #define TASK_UNMAPPED_BASE 0xC0000000UL #else #define TASK_UNMAPPED_BASE 0x0A000000UL #endif #define TASK_UNMAPPED_ALIGN(addr, off) PAGE_ALIGN(addr) struct thread_struct { unsigned long ksp; /* kernel stack pointer */ unsigned long usp; /* user stack pointer */ unsigned short sr; /* saved status register */ unsigned short fs; /* saved fs (sfc, dfc) */ unsigned long crp[2]; /* cpu root pointer */ unsigned long esp0; /* points to SR of stack frame */ unsigned long faddr; /* info about last fault */ int signo, code; unsigned long fp[8*3]; unsigned long fpcntl[3]; /* fp control regs */ unsigned char fpstate[FPSTATESIZE]; /* floating point state */ struct thread_info info; }; #define INIT_THREAD { \ .ksp = sizeof(init_stack) + (unsigned long) init_stack, \ .sr = PS_S, \ .fs = __KERNEL_DS, \ .info = INIT_THREAD_INFO(init_task), \ } /* * Do necessary setup to start up a newly executed thread. */ static inline void start_thread(struct pt_regs * regs, unsigned long pc, unsigned long usp) { /* reads from user space */ set_fs(USER_DS); regs->pc = pc; regs->sr &= ~0x2000; wrusp(usp); } /* Forward declaration, a strange C thing */ struct task_struct; /* Free all resources held by a thread. */ static inline void release_thread(struct task_struct *dead_task) { } /* Prepare to copy thread state - unlazy all lazy status */ #define prepare_to_copy(tsk) do { } while (0) extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags); /* * Free current thread data structures etc.. */ static inline void exit_thread(void) { } extern unsigned long thread_saved_pc(struct task_struct *tsk); unsigned long get_wchan(struct task_struct *p); #define KSTK_EIP(tsk) \ ({ \ unsigned long eip = 0; \ if ((tsk)->thread.esp0 > PAGE_SIZE && \ (virt_addr_valid((tsk)->thread.esp0))) \ eip = ((struct pt_regs *) (tsk)->thread.esp0)->pc; \ eip; }) #define KSTK_ESP(tsk) ((tsk) == current ? rdusp() : (tsk)->thread.usp) #define cpu_relax() barrier() #endif