include/asm/processor.h

0001 /* SPDX-License-Identifier: GPL-2.0-only */
0002 /*
0003  * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
0004  *
0005  * vineetg: March 2009
0006  *  -Implemented task_pt_regs( )
0007  *
0008  * Amit Bhor, Sameer Dhavale, Ashwin Chaugule: Codito Technologies 2004
0009  */
0010
0011 #ifndef __ASM_ARC_PROCESSOR_H
0012 #define __ASM_ARC_PROCESSOR_H
0013
0014 #ifndef __ASSEMBLY__
0015
0016 #include <asm/ptrace.h>
0017 #include <asm/dsp.h>
0018 #include <asm/fpu.h>
0019
0020 /* Arch specific stuff which needs to be saved per task.
0021  * However these items are not so important so as to earn a place in
0022  * struct thread_info
0023  */
0024 struct thread_struct {
0025     unsigned long ksp;  /* kernel mode stack pointer */
0026     unsigned long callee_reg;   /* pointer to callee regs */
0027     unsigned long fault_address;    /* dbls as brkpt holder as well */
0028 #ifdef CONFIG_ARC_DSP_SAVE_RESTORE_REGS
0029     struct dsp_callee_regs dsp;
0030 #endif
0031 #ifdef CONFIG_ARC_FPU_SAVE_RESTORE
0032     struct arc_fpu fpu;
0033 #endif
0034 };
0035
0036 #define INIT_THREAD  {                          \
0037     .ksp = sizeof(init_stack) + (unsigned long) init_stack, \
0038 }
0039
0040 /* Forward declaration, a strange C thing */
0041 struct task_struct;
0042
0043 #define task_pt_regs(p) \
0044     ((struct pt_regs *)(THREAD_SIZE + (void *)task_stack_page(p)) - 1)
0045
0046 /* Free all resources held by a thread */
0047 #define release_thread(thread) do { } while (0)
0048
0049 /*
0050  * A lot of busy-wait loops in SMP are based off of non-volatile data otherwise
0051  * get optimised away by gcc
0052  */
0053 #define cpu_relax()     barrier()
0054
0055 #define KSTK_EIP(tsk)   (task_pt_regs(tsk)->ret)
0056 #define KSTK_ESP(tsk)   (task_pt_regs(tsk)->sp)
0057
0058 /*
0059  * Where about of Task's sp, fp, blink when it was last seen in kernel mode.
0060  * Look in process.c for details of kernel stack layout
0061  */
0062 #define TSK_K_ESP(tsk)      (tsk->thread.ksp)
0063
0064 #define TSK_K_REG(tsk, off) (*((unsigned long *)(TSK_K_ESP(tsk) + \
0065                     sizeof(struct callee_regs) + off)))
0066
0067 #define TSK_K_BLINK(tsk)    TSK_K_REG(tsk, 4)
0068 #define TSK_K_FP(tsk)       TSK_K_REG(tsk, 0)
0069
0070 extern void start_thread(struct pt_regs * regs, unsigned long pc,
0071              unsigned long usp);
0072
0073 extern unsigned int __get_wchan(struct task_struct *p);
0074
0075 #endif /* !__ASSEMBLY__ */
0076
0077 /*
0078  * Default System Memory Map on ARC
0079  *
0080  * ---------------------------- (lower 2G, Translated) -------------------------
0081  * 0x0000_0000      0x5FFF_FFFF (user vaddr: TASK_SIZE)
0082  * 0x6000_0000      0x6FFF_FFFF (reserved gutter between U/K)
0083  * 0x7000_0000      0x7FFF_FFFF (kvaddr: vmalloc/modules/pkmap..)
0084  *
0085  * PAGE_OFFSET ---------------- (Upper 2G, Untranslated) -----------------------
0086  * 0x8000_0000      0xBFFF_FFFF (kernel direct mapped)
0087  * 0xC000_0000      0xFFFF_FFFF (peripheral uncached space)
0088  * -----------------------------------------------------------------------------
0089  */
0090
0091 #define TASK_SIZE   0x60000000
0092
0093 #define VMALLOC_START   (PAGE_OFFSET - (CONFIG_ARC_KVADDR_SIZE << 20))
0094
0095 /* 1 PGDIR_SIZE each for fixmap/pkmap, 2 PGDIR_SIZE gutter (see asm/highmem.h) */
0096 #define VMALLOC_SIZE    ((CONFIG_ARC_KVADDR_SIZE << 20) - PMD_SIZE * 4)
0097
0098 #define VMALLOC_END (VMALLOC_START + VMALLOC_SIZE)
0099
0100 #define USER_KERNEL_GUTTER    (VMALLOC_START - TASK_SIZE)
0101
0102 #define STACK_TOP       TASK_SIZE
0103 #define STACK_TOP_MAX   STACK_TOP
0104
0105 /* This decides where the kernel will search for a free chunk of vm
0106  * space during mmap's.
0107  */
0108 #define TASK_UNMAPPED_BASE      (TASK_SIZE / 3)
0109
0110 #endif /* __ASM_ARC_PROCESSOR_H */