1 /*
2 * arch/arm/include/asm/processor.h
3 *
4 * Copyright (C) 1995-1999 Russell King
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10
11 #ifndef __ASM_ARM_PROCESSOR_H
12 #define __ASM_ARM_PROCESSOR_H
13
14 /*
15 * Default implementation of macro that returns current
16 * instruction pointer ("program counter").
17 */
18 #define current_text_addr() ({ __label__ _l; _l: &&_l;})
19
20 #ifdef __KERNEL__
21
22 #include <asm/hw_breakpoint.h>
23 #include <asm/ptrace.h>
24 #include <asm/types.h>
25 #include <asm/unified.h>
26
27 #ifdef __KERNEL__
28 #define STACK_TOP ((current->personality & ADDR_LIMIT_32BIT) ? \
29 TASK_SIZE : TASK_SIZE_26)
30 #define STACK_TOP_MAX TASK_SIZE
31 #endif
32
33 struct debug_info {
34 #ifdef CONFIG_HAVE_HW_BREAKPOINT
35 struct perf_event *hbp[ARM_MAX_HBP_SLOTS];
36 #endif
37 };
38
39 struct thread_struct {
40 /* fault info */
41 unsigned long address;
42 unsigned long trap_no;
43 unsigned long error_code;
44 /* debugging */
45 struct debug_info debug;
46 };
47
48 /*
49 * Everything usercopied to/from thread_struct is statically-sized, so
50 * no hardened usercopy whitelist is needed.
51 */
arch_thread_struct_whitelist(unsigned long * offset,unsigned long * size)52 static inline void arch_thread_struct_whitelist(unsigned long *offset,
53 unsigned long *size)
54 {
55 *offset = *size = 0;
56 }
57
58 #define INIT_THREAD { }
59
60 #define start_thread(regs,pc,sp) \
61 ({ \
62 unsigned long r7, r8, r9; \
63 \
64 if (IS_ENABLED(CONFIG_BINFMT_ELF_FDPIC)) { \
65 r7 = regs->ARM_r7; \
66 r8 = regs->ARM_r8; \
67 r9 = regs->ARM_r9; \
68 } \
69 memset(regs->uregs, 0, sizeof(regs->uregs)); \
70 if (IS_ENABLED(CONFIG_BINFMT_ELF_FDPIC) && \
71 current->personality & FDPIC_FUNCPTRS) { \
72 regs->ARM_r7 = r7; \
73 regs->ARM_r8 = r8; \
74 regs->ARM_r9 = r9; \
75 regs->ARM_r10 = current->mm->start_data; \
76 } else if (!IS_ENABLED(CONFIG_MMU)) \
77 regs->ARM_r10 = current->mm->start_data; \
78 if (current->personality & ADDR_LIMIT_32BIT) \
79 regs->ARM_cpsr = USR_MODE; \
80 else \
81 regs->ARM_cpsr = USR26_MODE; \
82 if (elf_hwcap & HWCAP_THUMB && pc & 1) \
83 regs->ARM_cpsr |= PSR_T_BIT; \
84 regs->ARM_cpsr |= PSR_ENDSTATE; \
85 regs->ARM_pc = pc & ~1; /* pc */ \
86 regs->ARM_sp = sp; /* sp */ \
87 })
88
89 /* Forward declaration, a strange C thing */
90 struct task_struct;
91
92 /* Free all resources held by a thread. */
93 extern void release_thread(struct task_struct *);
94
95 unsigned long get_wchan(struct task_struct *p);
96
97 #if __LINUX_ARM_ARCH__ == 6 || defined(CONFIG_ARM_ERRATA_754327)
98 #define cpu_relax() smp_mb()
99 #else
100 #define cpu_relax() barrier()
101 #endif
102
103 #define task_pt_regs(p) \
104 ((struct pt_regs *)(THREAD_START_SP + task_stack_page(p)) - 1)
105
106 #define KSTK_EIP(tsk) task_pt_regs(tsk)->ARM_pc
107 #define KSTK_ESP(tsk) task_pt_regs(tsk)->ARM_sp
108
109 #ifdef CONFIG_SMP
110 #define __ALT_SMP_ASM(smp, up) \
111 "9998: " smp "\n" \
112 " .pushsection \".alt.smp.init\", \"a\"\n" \
113 " .long 9998b\n" \
114 " " up "\n" \
115 " .popsection\n"
116 #else
117 #define __ALT_SMP_ASM(smp, up) up
118 #endif
119
120 /*
121 * Prefetching support - only ARMv5.
122 */
123 #if __LINUX_ARM_ARCH__ >= 5
124
125 #define ARCH_HAS_PREFETCH
prefetch(const void * ptr)126 static inline void prefetch(const void *ptr)
127 {
128 __asm__ __volatile__(
129 "pld\t%a0"
130 :: "p" (ptr));
131 }
132
133 #if __LINUX_ARM_ARCH__ >= 7 && defined(CONFIG_SMP)
134 #define ARCH_HAS_PREFETCHW
prefetchw(const void * ptr)135 static inline void prefetchw(const void *ptr)
136 {
137 __asm__ __volatile__(
138 ".arch_extension mp\n"
139 __ALT_SMP_ASM(
140 WASM(pldw) "\t%a0",
141 WASM(pld) "\t%a0"
142 )
143 :: "p" (ptr));
144 }
145 #endif
146 #endif
147
148 #define HAVE_ARCH_PICK_MMAP_LAYOUT
149
150 #endif
151
152 #endif /* __ASM_ARM_PROCESSOR_H */
153
