xref: /linux/arch/arm64/include/asm/processor.h (revision 2ba9268dd603d23e17643437b2246acb6844953b)
1 /*
2  * Based on arch/arm/include/asm/processor.h
3  *
4  * Copyright (C) 1995-1999 Russell King
5  * Copyright (C) 2012 ARM Ltd.
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
18  */
19 #ifndef __ASM_PROCESSOR_H
20 #define __ASM_PROCESSOR_H
21 
22 /*
23  * Default implementation of macro that returns current
24  * instruction pointer ("program counter").
25  */
26 #define current_text_addr() ({ __label__ _l; _l: &&_l;})
27 
28 #ifdef __KERNEL__
29 
30 #include <linux/string.h>
31 
32 #include <asm/fpsimd.h>
33 #include <asm/hw_breakpoint.h>
34 #include <asm/pgtable-hwdef.h>
35 #include <asm/ptrace.h>
36 #include <asm/types.h>
37 
38 #ifdef __KERNEL__
39 #define STACK_TOP_MAX		TASK_SIZE_64
40 #ifdef CONFIG_COMPAT
41 #define AARCH32_VECTORS_BASE	0xffff0000
42 #define STACK_TOP		(test_thread_flag(TIF_32BIT) ? \
43 				AARCH32_VECTORS_BASE : STACK_TOP_MAX)
44 #else
45 #define STACK_TOP		STACK_TOP_MAX
46 #endif /* CONFIG_COMPAT */
47 
48 extern phys_addr_t arm64_dma_phys_limit;
49 #define ARCH_LOW_ADDRESS_LIMIT	(arm64_dma_phys_limit - 1)
50 #endif /* __KERNEL__ */
51 
52 struct debug_info {
53 	/* Have we suspended stepping by a debugger? */
54 	int			suspended_step;
55 	/* Allow breakpoints and watchpoints to be disabled for this thread. */
56 	int			bps_disabled;
57 	int			wps_disabled;
58 	/* Hardware breakpoints pinned to this task. */
59 	struct perf_event	*hbp_break[ARM_MAX_BRP];
60 	struct perf_event	*hbp_watch[ARM_MAX_WRP];
61 };
62 
63 struct cpu_context {
64 	unsigned long x19;
65 	unsigned long x20;
66 	unsigned long x21;
67 	unsigned long x22;
68 	unsigned long x23;
69 	unsigned long x24;
70 	unsigned long x25;
71 	unsigned long x26;
72 	unsigned long x27;
73 	unsigned long x28;
74 	unsigned long fp;
75 	unsigned long sp;
76 	unsigned long pc;
77 };
78 
79 struct thread_struct {
80 	struct cpu_context	cpu_context;	/* cpu context */
81 	unsigned long		tp_value;
82 	struct fpsimd_state	fpsimd_state;
83 	unsigned long		fault_address;	/* fault info */
84 	unsigned long		fault_code;	/* ESR_EL1 value */
85 	struct debug_info	debug;		/* debugging */
86 };
87 
88 #define INIT_THREAD  {	}
89 
90 static inline void start_thread_common(struct pt_regs *regs, unsigned long pc)
91 {
92 	memset(regs, 0, sizeof(*regs));
93 	regs->syscallno = ~0UL;
94 	regs->pc = pc;
95 }
96 
97 static inline void start_thread(struct pt_regs *regs, unsigned long pc,
98 				unsigned long sp)
99 {
100 	start_thread_common(regs, pc);
101 	regs->pstate = PSR_MODE_EL0t;
102 	regs->sp = sp;
103 }
104 
105 #ifdef CONFIG_COMPAT
106 static inline void compat_start_thread(struct pt_regs *regs, unsigned long pc,
107 				       unsigned long sp)
108 {
109 	start_thread_common(regs, pc);
110 	regs->pstate = COMPAT_PSR_MODE_USR;
111 	if (pc & 1)
112 		regs->pstate |= COMPAT_PSR_T_BIT;
113 
114 #ifdef __AARCH64EB__
115 	regs->pstate |= COMPAT_PSR_E_BIT;
116 #endif
117 
118 	regs->compat_sp = sp;
119 }
120 #endif
121 
122 /* Forward declaration, a strange C thing */
123 struct task_struct;
124 
125 /* Free all resources held by a thread. */
126 extern void release_thread(struct task_struct *);
127 
128 unsigned long get_wchan(struct task_struct *p);
129 
130 #define cpu_relax()			barrier()
131 #define cpu_relax_lowlatency()                cpu_relax()
132 
133 /* Thread switching */
134 extern struct task_struct *cpu_switch_to(struct task_struct *prev,
135 					 struct task_struct *next);
136 
137 #define task_pt_regs(p) \
138 	((struct pt_regs *)(THREAD_START_SP + task_stack_page(p)) - 1)
139 
140 #define KSTK_EIP(tsk)	((unsigned long)task_pt_regs(tsk)->pc)
141 #define KSTK_ESP(tsk)	user_stack_pointer(task_pt_regs(tsk))
142 
143 /*
144  * Prefetching support
145  */
146 #define ARCH_HAS_PREFETCH
147 static inline void prefetch(const void *ptr)
148 {
149 	asm volatile("prfm pldl1keep, %a0\n" : : "p" (ptr));
150 }
151 
152 #define ARCH_HAS_PREFETCHW
153 static inline void prefetchw(const void *ptr)
154 {
155 	asm volatile("prfm pstl1keep, %a0\n" : : "p" (ptr));
156 }
157 
158 #define ARCH_HAS_SPINLOCK_PREFETCH
159 static inline void spin_lock_prefetch(const void *x)
160 {
161 	prefetchw(x);
162 }
163 
164 #define HAVE_ARCH_PICK_MMAP_LAYOUT
165 
166 #endif
167 
168 #endif /* __ASM_PROCESSOR_H */
169