arch/arc/include/asm/processor.h

root/arch/arc/include/asm/processor.h
/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
 *
 * 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 __ASSEMBLER__

#include <asm/ptrace.h>
#include <asm/dsp.h>
#include <asm/fpu.h>

/* 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 callee_reg;       /* pointer to callee regs */
        unsigned long fault_address;    /* dbls as brkpt holder as well */
#ifdef CONFIG_ARC_DSP_SAVE_RESTORE_REGS
        struct dsp_callee_regs dsp;
#endif
#ifdef CONFIG_ARC_FPU_SAVE_RESTORE
        struct arc_fpu fpu;
#endif
};

#define INIT_THREAD  { }

/* 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)

/*
 * A lot of busy-wait loops in SMP are based off of non-volatile data otherwise
 * get optimised away by gcc
 */
#define cpu_relax()             barrier()

#define KSTK_EIP(tsk)   (task_pt_regs(tsk)->ret)
#define KSTK_ESP(tsk)   (task_pt_regs(tsk)->sp)

/*
 * Where about 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)          (task_thread_info(tsk)->ksp)

#define TSK_K_REG(tsk, off)     (*((unsigned long *)(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)

extern void start_thread(struct pt_regs * regs, unsigned long pc,
                         unsigned long usp);

extern unsigned int __get_wchan(struct task_struct *p);

#endif /* !__ASSEMBLER__ */

/*
 * Default System Memory Map on ARC
 *
 * ---------------------------- (lower 2G, Translated) -------------------------
 * 0x0000_0000          0x5FFF_FFFF     (user vaddr: TASK_SIZE)
 * 0x6000_0000          0x6FFF_FFFF     (reserved gutter between U/K)
 * 0x7000_0000          0x7FFF_FFFF     (kvaddr: vmalloc/modules/pkmap..)
 *
 * PAGE_OFFSET ---------------- (Upper 2G, Untranslated) -----------------------
 * 0x8000_0000          0xBFFF_FFFF     (kernel direct mapped)
 * 0xC000_0000          0xFFFF_FFFF     (peripheral uncached space)
 * -----------------------------------------------------------------------------
 */

#define TASK_SIZE       0x60000000

#define VMALLOC_START   (PAGE_OFFSET - (CONFIG_ARC_KVADDR_SIZE << 20))

/* 1 PGDIR_SIZE each for fixmap/pkmap, 2 PGDIR_SIZE gutter (see asm/highmem.h) */
#define VMALLOC_SIZE    ((CONFIG_ARC_KVADDR_SIZE << 20) - PMD_SIZE * 4)

#define VMALLOC_END     (VMALLOC_START + VMALLOC_SIZE)

#define USER_KERNEL_GUTTER    (VMALLOC_START - TASK_SIZE)

#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 */
Linux
