LXR linux/arch/arc/include/asm/processor.h

   1/* SPDX-License-Identifier: GPL-2.0-only */
   2/*
   3 * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
   4 *
   5 * vineetg: March 2009
   6 *  -Implemented task_pt_regs( )
   7 *
   8 * Amit Bhor, Sameer Dhavale, Ashwin Chaugule: Codito Technologies 2004
   9 */
  10
  11#ifndef __ASM_ARC_PROCESSOR_H
  12#define __ASM_ARC_PROCESSOR_H
  13
  14#ifndef __ASSEMBLY__
  15
  16#include <asm/ptrace.h>
  17#include <asm/dsp.h>
  18#include <asm/fpu.h>
  19
  20/* Arch specific stuff which needs to be saved per task.
  21 * However these items are not so important so as to earn a place in
  22 * struct thread_info
  23 */
  24struct thread_struct {
  25        unsigned long ksp;      /* kernel mode stack pointer */
  26        unsigned long callee_reg;       /* pointer to callee regs */
  27        unsigned long fault_address;    /* dbls as brkpt holder as well */
  28#ifdef CONFIG_ARC_DSP_SAVE_RESTORE_REGS
  29        struct dsp_callee_regs dsp;
  30#endif
  31#ifdef CONFIG_ARC_FPU_SAVE_RESTORE
  32        struct arc_fpu fpu;
  33#endif
  34};
  35
  36#define INIT_THREAD  {                          \
  37        .ksp = sizeof(init_stack) + (unsigned long) init_stack, \
  38}
  39
  40/* Forward declaration, a strange C thing */
  41struct task_struct;
  42
  43#define task_pt_regs(p) \
  44        ((struct pt_regs *)(THREAD_SIZE + (void *)task_stack_page(p)) - 1)
  45
  46/* Free all resources held by a thread */
  47#define release_thread(thread) do { } while (0)
  48
  49/*
  50 * A lot of busy-wait loops in SMP are based off of non-volatile data otherwise
  51 * get optimised away by gcc
  52 */
  53#define cpu_relax()             barrier()
  54
  55#define KSTK_EIP(tsk)   (task_pt_regs(tsk)->ret)
  56#define KSTK_ESP(tsk)   (task_pt_regs(tsk)->sp)
  57
  58/*
  59 * Where about of Task's sp, fp, blink when it was last seen in kernel mode.
  60 * Look in process.c for details of kernel stack layout
  61 */
  62#define TSK_K_ESP(tsk)          (tsk->thread.ksp)
  63
  64#define TSK_K_REG(tsk, off)     (*((unsigned long *)(TSK_K_ESP(tsk) + \
  65                                        sizeof(struct callee_regs) + off)))
  66
  67#define TSK_K_BLINK(tsk)        TSK_K_REG(tsk, 4)
  68#define TSK_K_FP(tsk)           TSK_K_REG(tsk, 0)
  69
  70extern void start_thread(struct pt_regs * regs, unsigned long pc,
  71                         unsigned long usp);
  72
  73extern unsigned int get_wchan(struct task_struct *p);
  74
  75#endif /* !__ASSEMBLY__ */
  76
  77/*
  78 * Default System Memory Map on ARC
  79 *
  80 * ---------------------------- (lower 2G, Translated) -------------------------
  81 * 0x0000_0000          0x5FFF_FFFF     (user vaddr: TASK_SIZE)
  82 * 0x6000_0000          0x6FFF_FFFF     (reserved gutter between U/K)
  83 * 0x7000_0000          0x7FFF_FFFF     (kvaddr: vmalloc/modules/pkmap..)
  84 *
  85 * PAGE_OFFSET ---------------- (Upper 2G, Untranslated) -----------------------
  86 * 0x8000_0000          0xBFFF_FFFF     (kernel direct mapped)
  87 * 0xC000_0000          0xFFFF_FFFF     (peripheral uncached space)
  88 * -----------------------------------------------------------------------------
  89 */
  90
  91#define TASK_SIZE       0x60000000
  92
  93#define VMALLOC_START   (PAGE_OFFSET - (CONFIG_ARC_KVADDR_SIZE << 20))
  94
  95/* 1 PGDIR_SIZE each for fixmap/pkmap, 2 PGDIR_SIZE gutter (see asm/highmem.h) */
  96#define VMALLOC_SIZE    ((CONFIG_ARC_KVADDR_SIZE << 20) - PMD_SIZE * 4)
  97
  98#define VMALLOC_END     (VMALLOC_START + VMALLOC_SIZE)
  99
 100#define USER_KERNEL_GUTTER    (VMALLOC_START - TASK_SIZE)
 101
 102#define STACK_TOP       TASK_SIZE
 103#define STACK_TOP_MAX   STACK_TOP
 104
 105/* This decides where the kernel will search for a free chunk of vm
 106 * space during mmap's.
 107 */
 108#define TASK_UNMAPPED_BASE      (TASK_SIZE / 3)
 109
 110#endif /* __ASM_ARC_PROCESSOR_H */
 111