1 /* SPDX-License-Identifier: GPL-2.0-only */
3 * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
6 * -Implemented task_pt_regs( )
8 * Amit Bhor, Sameer Dhavale, Ashwin Chaugule: Codito Technologies 2004
11 #ifndef __ASM_ARC_PROCESSOR_H
12 #define __ASM_ARC_PROCESSOR_H
16 #include <asm/ptrace.h>
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
24 struct 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;
31 #ifdef CONFIG_ARC_FPU_SAVE_RESTORE
36 #define INIT_THREAD { \
37 .ksp = sizeof(init_stack) + (unsigned long) init_stack, \
40 /* Forward declaration, a strange C thing */
43 #define task_pt_regs(p) \
44 ((struct pt_regs *)(THREAD_SIZE + (void *)task_stack_page(p)) - 1)
46 /* Free all resources held by a thread */
47 #define release_thread(thread) do { } while (0)
50 * A lot of busy-wait loops in SMP are based off of non-volatile data otherwise
51 * get optimised away by gcc
53 #define cpu_relax() barrier()
55 #define KSTK_EIP(tsk) (task_pt_regs(tsk)->ret)
56 #define KSTK_ESP(tsk) (task_pt_regs(tsk)->sp)
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
62 #define TSK_K_ESP(tsk) (tsk->thread.ksp)
64 #define TSK_K_REG(tsk, off) (*((unsigned long *)(TSK_K_ESP(tsk) + \
65 sizeof(struct callee_regs) + off)))
67 #define TSK_K_BLINK(tsk) TSK_K_REG(tsk, 4)
68 #define TSK_K_FP(tsk) TSK_K_REG(tsk, 0)
70 extern void start_thread(struct pt_regs * regs, unsigned long pc,
73 extern unsigned int get_wchan(struct task_struct *p);
75 #endif /* !__ASSEMBLY__ */
78 * Default System Memory Map on ARC
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..)
85 * PAGE_OFFSET ---------------- (Upper 2G, Untranslated) -----------------------
86 * 0x8000_0000 0xBFFF_FFFF (kernel direct mapped)
87 * 0xC000_0000 0xFFFF_FFFF (peripheral uncached space)
88 * -----------------------------------------------------------------------------
91 #define TASK_SIZE 0x60000000
93 #define VMALLOC_START (PAGE_OFFSET - (CONFIG_ARC_KVADDR_SIZE << 20))
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) - PGDIR_SIZE * 4)
98 #define VMALLOC_END (VMALLOC_START + VMALLOC_SIZE)
100 #define USER_KERNEL_GUTTER (VMALLOC_START - TASK_SIZE)
102 #define STACK_TOP TASK_SIZE
103 #define STACK_TOP_MAX STACK_TOP
105 /* This decides where the kernel will search for a free chunk of vm
106 * space during mmap's.
108 #define TASK_UNMAPPED_BASE (TASK_SIZE / 3)
110 #endif /* __ASM_ARC_PROCESSOR_H */