/* * 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 #include #include #include extern inline unsigned long rdusp(void) { unsigned long usp; __asm__ __volatile__("move %/usp,%0" : "=a" (usp)); return usp; } extern 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 #ifdef __ASSEMBLY__ #define TASK_SIZE (0x0E000000) #else #define TASK_SIZE (0x0E000000UL) #endif #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) /* * Bus types */ #define EISA_bus 0 #define MCA_bus 0 /* * if you change this structure, you must change the code and offsets * in m68k/machasm.S */ 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 */ }; #define INIT_THREAD { \ sizeof(init_stack) + (unsigned long) init_stack, 0, \ PS_S, __KERNEL_DS, \ } /* * 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) { } extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags); #define copy_segments(tsk, mm) do { } while (0) #define release_segments(mm) do { } while (0) /* * Free current thread data structures etc.. */ static inline void exit_thread(void) { } /* * Return saved PC of a blocked thread. */ extern inline unsigned long thread_saved_pc(struct thread_struct *t) { extern void scheduling_functions_start_here(void); extern void scheduling_functions_end_here(void); struct switch_stack *sw = (struct switch_stack *)t->ksp; /* Check whether the thread is blocked in resume() */ if (sw->retpc > (unsigned long)scheduling_functions_start_here && sw->retpc < (unsigned long)scheduling_functions_end_here) return ((unsigned long *)sw->a6)[1]; else return sw->retpc; } unsigned long get_wchan(struct task_struct *p); #define KSTK_EIP(tsk) \ ({ \ unsigned long eip = 0; \ if ((tsk)->thread.esp0 > PAGE_SIZE && \ (VALID_PAGE(virt_to_page((tsk)->thread.esp0)))) \ eip = ((struct pt_regs *) (tsk)->thread.esp0)->pc; \ eip; }) #define KSTK_ESP(tsk) ((tsk) == current ? rdusp() : (tsk)->thread.usp) #define THREAD_SIZE (2*PAGE_SIZE) /* Allocation and freeing of basic task resources. */ #define alloc_task_struct() \ ((struct task_struct *) __get_free_pages(GFP_KERNEL,1)) #define free_task_struct(p) free_pages((unsigned long)(p),1) #define get_task_struct(tsk) atomic_inc(&virt_to_page(tsk)->count) #define init_task (init_task_union.task) #define init_stack (init_task_union.stack) #define cpu_relax() do { } while (0) #endif