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>
19 #ifdef CONFIG_ARC_PLAT_EZNPS
26 /* Arch specific stuff which needs to be saved per task.
27 * However these items are not so important so as to earn a place in
30 struct thread_struct {
31 unsigned long ksp; /* kernel mode stack pointer */
32 unsigned long callee_reg; /* pointer to callee regs */
33 unsigned long fault_address; /* dbls as brkpt holder as well */
34 #ifdef CONFIG_ARC_FPU_SAVE_RESTORE
37 #ifdef CONFIG_ARC_PLAT_EZNPS
42 #define INIT_THREAD { \
43 .ksp = sizeof(init_stack) + (unsigned long) init_stack, \
46 /* Forward declaration, a strange C thing */
49 #define task_pt_regs(p) \
50 ((struct pt_regs *)(THREAD_SIZE + (void *)task_stack_page(p)) - 1)
52 /* Free all resources held by a thread */
53 #define release_thread(thread) do { } while (0)
56 * A lot of busy-wait loops in SMP are based off of non-volatile data otherwise
57 * get optimised away by gcc
59 #ifndef CONFIG_EZNPS_MTM_EXT
61 #define cpu_relax() barrier()
66 __asm__ __volatile__ (".word %0" : : "i"(CTOP_INST_SCHD_RW) : "memory")
70 #define KSTK_EIP(tsk) (task_pt_regs(tsk)->ret)
71 #define KSTK_ESP(tsk) (task_pt_regs(tsk)->sp)
74 * Where about of Task's sp, fp, blink when it was last seen in kernel mode.
75 * Look in process.c for details of kernel stack layout
77 #define TSK_K_ESP(tsk) (tsk->thread.ksp)
79 #define TSK_K_REG(tsk, off) (*((unsigned long *)(TSK_K_ESP(tsk) + \
80 sizeof(struct callee_regs) + off)))
82 #define TSK_K_BLINK(tsk) TSK_K_REG(tsk, 4)
83 #define TSK_K_FP(tsk) TSK_K_REG(tsk, 0)
85 extern void start_thread(struct pt_regs * regs, unsigned long pc,
88 extern unsigned int get_wchan(struct task_struct *p);
90 #endif /* !__ASSEMBLY__ */
93 * Default System Memory Map on ARC
95 * ---------------------------- (lower 2G, Translated) -------------------------
96 * 0x0000_0000 0x5FFF_FFFF (user vaddr: TASK_SIZE)
97 * 0x6000_0000 0x6FFF_FFFF (reserved gutter between U/K)
98 * 0x7000_0000 0x7FFF_FFFF (kvaddr: vmalloc/modules/pkmap..)
100 * PAGE_OFFSET ---------------- (Upper 2G, Untranslated) -----------------------
101 * 0x8000_0000 0xBFFF_FFFF (kernel direct mapped)
102 * 0xC000_0000 0xFFFF_FFFF (peripheral uncached space)
103 * -----------------------------------------------------------------------------
106 #define TASK_SIZE 0x60000000
108 #define VMALLOC_START (PAGE_OFFSET - (CONFIG_ARC_KVADDR_SIZE << 20))
110 /* 1 PGDIR_SIZE each for fixmap/pkmap, 2 PGDIR_SIZE gutter (see asm/highmem.h) */
111 #define VMALLOC_SIZE ((CONFIG_ARC_KVADDR_SIZE << 20) - PGDIR_SIZE * 4)
113 #define VMALLOC_END (VMALLOC_START + VMALLOC_SIZE)
115 #define USER_KERNEL_GUTTER (VMALLOC_START - TASK_SIZE)
117 #ifdef CONFIG_ARC_PLAT_EZNPS
118 /* NPS architecture defines special window of 129M in user address space for
119 * special memory areas, when accessing this window the MMU do not use TLB.
120 * Instead MMU direct the access to:
121 * 0x57f00000:0x57ffffff -- 1M of closely coupled memory (aka CMEM)
122 * 0x58000000:0x5fffffff -- 16 huge pages, 8M each, with fixed map (aka FMTs)
124 * CMEM - is the fastest memory we got and its size is 16K.
125 * FMT - is used to map either to internal/external memory.
126 * Internal memory is the second fast memory and its size is 16M
127 * External memory is the biggest memory (16G) and also the slowest.
129 * STACK_TOP need to be PMD align (21bit) that is why we supply 0x57e00000.
131 #define STACK_TOP 0x57e00000
133 #define STACK_TOP TASK_SIZE
136 #define STACK_TOP_MAX STACK_TOP
138 /* This decides where the kernel will search for a free chunk of vm
139 * space during mmap's.
141 #define TASK_UNMAPPED_BASE (TASK_SIZE / 3)
143 #endif /* __ASM_ARC_PROCESSOR_H */