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Diffstat (limited to 'kernel/arch/arc/include/asm/processor.h')
| -rw-r--r-- | kernel/arch/arc/include/asm/processor.h | 135 |
1 files changed, 135 insertions, 0 deletions
diff --git a/kernel/arch/arc/include/asm/processor.h b/kernel/arch/arc/include/asm/processor.h new file mode 100644 index 000000000..52312cb5d --- /dev/null +++ b/kernel/arch/arc/include/asm/processor.h @@ -0,0 +1,135 @@ +/* + * 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 */ |