/* * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. * * vineetg: March 2009 *  -Implemented task_pt_regs( ) * * Amit Bhor, Sameer Dhavale, Ashwin Chaugule: Codito Technologies 2004 */ #ifndef __ASM_ARC_PROCESSOR_H#define __ASM_ARC_PROCESSOR_H #ifndef __ASSEMBLY__ #include <asm/ptrace.h> #ifdef CONFIG_ARC_FPU_SAVE_RESTORE/* These DPFP regs need to be saved/restored across ctx-sw */struct arc_fpu {	struct {		unsigned int l, h;	} aux_dpfp[2];};#endif /* Arch specific stuff which needs to be saved per task. * However these items are not so important so as to earn a place in * struct thread_info */struct thread_struct {	unsigned long ksp;	/* kernel mode stack pointer */	unsigned long callee_reg;	/* pointer to callee regs */	unsigned long fault_address;	/* dbls as brkpt holder as well */#ifdef CONFIG_ARC_FPU_SAVE_RESTORE	struct arc_fpu fpu;#endif}; #define INIT_THREAD  {                          \	.ksp = sizeof(init_stack) + (unsigned long) init_stack, \} /* Forward declaration, a strange C thing */struct task_struct; #define task_pt_regs(p) \	((struct pt_regs *)(THREAD_SIZE + (void *)task_stack_page(p)) - 1) /* Free all resources held by a thread */#define release_thread(thread) do { } while (0) /* * A lot of busy-wait loops in SMP are based off of non-volatile data otherwise * get optimised away by gcc */#ifdef CONFIG_SMP#define cpu_relax()	__asm__ __volatile__ ("" : : : "memory")#else#define cpu_relax()	do { } while (0)#endif #define cpu_relax_lowlatency() cpu_relax() #define copy_segments(tsk, mm)      do { } while (0)#define release_segments(mm)        do { } while (0) #define KSTK_EIP(tsk)   (task_pt_regs(tsk)->ret)#define KSTK_ESP(tsk)   (task_pt_regs(tsk)->sp) /* * Where abouts of Task's sp, fp, blink when it was last seen in kernel mode. * Look in process.c for details of kernel stack layout */#define TSK_K_ESP(tsk)		(tsk->thread.ksp) #define TSK_K_REG(tsk, off)	(*((unsigned int *)(TSK_K_ESP(tsk) + \					sizeof(struct callee_regs) + off))) #define TSK_K_BLINK(tsk)	TSK_K_REG(tsk, 4)#define TSK_K_FP(tsk)		TSK_K_REG(tsk, 0) #define thread_saved_pc(tsk)	TSK_K_BLINK(tsk) extern void start_thread(struct pt_regs * regs, unsigned long pc,			 unsigned long usp); extern unsigned int get_wchan(struct task_struct *p); /* * Default implementation of macro that returns current * instruction pointer ("program counter"). * Should the PC register be read instead ? This macro does not seem to * be used in many places so this wont be all that bad. */#define current_text_addr() ({ __label__ _l; _l: &&_l; }) #endif /* !__ASSEMBLY__ */ /* Kernels Virtual memory area. * Unlike other architectures(MIPS, sh, cris ) ARC 700 does not have a * "kernel translated" region (like KSEG2 in MIPS). So we use a upper part * of the translated bottom 2GB for kernel virtual memory and protect * these pages from user accesses by disabling Ru, Eu and Wu. */#define VMALLOC_SIZE	(0x10000000)	/* 256M */#define VMALLOC_START	(PAGE_OFFSET - VMALLOC_SIZE)#define VMALLOC_END	(PAGE_OFFSET) /* Most of the architectures seem to be keeping some kind of padding between * userspace TASK_SIZE and PAGE_OFFSET. i.e TASK_SIZE != PAGE_OFFSET. */#define USER_KERNEL_GUTTER    0x10000000 /* User address space: * On ARC700, CPU allows the entire lower half of 32 bit address space to be * translated. Thus potentially 2G (0:0x7FFF_FFFF) could be User vaddr space. * However we steal 256M for kernel addr (0x7000_0000:0x7FFF_FFFF) and another * 256M (0x6000_0000:0x6FFF_FFFF) is gutter between user/kernel spaces * Thus total User vaddr space is (0:0x5FFF_FFFF) */#define TASK_SIZE	(PAGE_OFFSET - VMALLOC_SIZE - USER_KERNEL_GUTTER) #define STACK_TOP       TASK_SIZE#define STACK_TOP_MAX   STACK_TOP /* This decides where the kernel will search for a free chunk of vm * space during mmap's. */#define TASK_UNMAPPED_BASE      (TASK_SIZE / 3) #endif /* __ASM_ARC_PROCESSOR_H */