/* * 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 #ifdef __KERNEL__ #ifndef __ASSEMBLY__ #include <asm/arcregs.h>	/* for STATUS_E1_MASK et all */ /* 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 */	unsigned long cause_code;	/* Exception Cause Code (ECR) */#ifdef CONFIG_ARC_CURR_IN_REG	unsigned long user_r25;#endif#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; /* * Return saved PC of a blocked thread. */unsigned long thread_saved_pc(struct task_struct *t); #define task_pt_regs(p) \	((struct pt_regs *)(THREAD_SIZE - 4 + (void *)task_stack_page(p)) - 1) /* Free all resources held by a thread. */#define release_thread(thread) do { } while (0) /* Prepare to copy thread state - unlazy all lazy status */#define prepare_to_copy(tsk)    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 copy_segments(tsk, mm)      do { } while (0)#define release_segments(mm)        do { } while (0) #define KSTK_EIP(tsk)   (task_pt_regs(tsk)->ret) /* * Where abouts of Task's sp, fp, blink when it was last seen in kernel mode. * These can't be derived from pt_regs as that would give correp user-mode val */#define KSTK_ESP(tsk)   (tsk->thread.ksp)#define KSTK_BLINK(tsk) (*((unsigned int *)((KSTK_ESP(tsk)) + (13+1+1)*4)))#define KSTK_FP(tsk)    (*((unsigned int *)((KSTK_ESP(tsk)) + (13+1)*4))) /* * Do necessary setup to start up a newly executed thread. * * E1,E2 so that Interrupts are enabled in user mode * L set, so Loop inhibited to begin with * lp_start and lp_end seeded with bogus non-zero values so to easily catch * the ARC700 sr to lp_start hardware bug */#define start_thread(_regs, _pc, _usp)				\do {								\	set_fs(USER_DS); /* reads from user space */		\	(_regs)->ret = (_pc);					\	/* Interrupts enabled in User Mode */			\	(_regs)->status32 = STATUS_U_MASK | STATUS_L_MASK	\		| STATUS_E1_MASK | STATUS_E2_MASK;		\	(_regs)->sp = (_usp);					\	/* bogus seed values for debugging */			\	(_regs)->lp_start = 0x10;				\	(_regs)->lp_end = 0x80;					\} while (0) 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 /* __KERNEL__ */ #endif /* __ASM_ARC_PROCESSOR_H */