xref: /openbmc/linux/arch/arm64/include/asm/processor.h (revision 54cbac81)
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/ptrace.h>
35 #include <asm/types.h>
36 
37 #ifdef __KERNEL__
38 #define STACK_TOP_MAX		TASK_SIZE_64
39 #ifdef CONFIG_COMPAT
40 #define AARCH32_VECTORS_BASE	0xffff0000
41 #define STACK_TOP		(test_thread_flag(TIF_32BIT) ? \
42 				AARCH32_VECTORS_BASE : STACK_TOP_MAX)
43 #else
44 #define STACK_TOP		STACK_TOP_MAX
45 #endif /* CONFIG_COMPAT */
46 
47 #define ARCH_LOW_ADDRESS_LIMIT	PHYS_MASK
48 #endif /* __KERNEL__ */
49 
50 struct debug_info {
51 	/* Have we suspended stepping by a debugger? */
52 	int			suspended_step;
53 	/* Allow breakpoints and watchpoints to be disabled for this thread. */
54 	int			bps_disabled;
55 	int			wps_disabled;
56 	/* Hardware breakpoints pinned to this task. */
57 	struct perf_event	*hbp_break[ARM_MAX_BRP];
58 	struct perf_event	*hbp_watch[ARM_MAX_WRP];
59 };
60 
61 struct cpu_context {
62 	unsigned long x19;
63 	unsigned long x20;
64 	unsigned long x21;
65 	unsigned long x22;
66 	unsigned long x23;
67 	unsigned long x24;
68 	unsigned long x25;
69 	unsigned long x26;
70 	unsigned long x27;
71 	unsigned long x28;
72 	unsigned long fp;
73 	unsigned long sp;
74 	unsigned long pc;
75 };
76 
77 struct thread_struct {
78 	struct cpu_context	cpu_context;	/* cpu context */
79 	unsigned long		tp_value;
80 	struct fpsimd_state	fpsimd_state;
81 	unsigned long		fault_address;	/* fault info */
82 	struct debug_info	debug;		/* debugging */
83 };
84 
85 #define INIT_THREAD  {	}
86 
87 static inline void start_thread_common(struct pt_regs *regs, unsigned long pc)
88 {
89 	memset(regs, 0, sizeof(*regs));
90 	regs->syscallno = ~0UL;
91 	regs->pc = pc;
92 }
93 
94 static inline void start_thread(struct pt_regs *regs, unsigned long pc,
95 				unsigned long sp)
96 {
97 	start_thread_common(regs, pc);
98 	regs->pstate = PSR_MODE_EL0t;
99 	regs->sp = sp;
100 }
101 
102 #ifdef CONFIG_COMPAT
103 static inline void compat_start_thread(struct pt_regs *regs, unsigned long pc,
104 				       unsigned long sp)
105 {
106 	start_thread_common(regs, pc);
107 	regs->pstate = COMPAT_PSR_MODE_USR;
108 	if (pc & 1)
109 		regs->pstate |= COMPAT_PSR_T_BIT;
110 	regs->compat_sp = sp;
111 }
112 #endif
113 
114 /* Forward declaration, a strange C thing */
115 struct task_struct;
116 
117 /* Free all resources held by a thread. */
118 extern void release_thread(struct task_struct *);
119 
120 /* Prepare to copy thread state - unlazy all lazy status */
121 #define prepare_to_copy(tsk)	do { } while (0)
122 
123 unsigned long get_wchan(struct task_struct *p);
124 
125 #define cpu_relax()			barrier()
126 
127 /* Thread switching */
128 extern struct task_struct *cpu_switch_to(struct task_struct *prev,
129 					 struct task_struct *next);
130 
131 #define task_pt_regs(p) \
132 	((struct pt_regs *)(THREAD_START_SP + task_stack_page(p)) - 1)
133 
134 #define KSTK_EIP(tsk)	task_pt_regs(tsk)->pc
135 #define KSTK_ESP(tsk)	task_pt_regs(tsk)->sp
136 
137 /*
138  * Prefetching support
139  */
140 #define ARCH_HAS_PREFETCH
141 static inline void prefetch(const void *ptr)
142 {
143 	asm volatile("prfm pldl1keep, %a0\n" : : "p" (ptr));
144 }
145 
146 #define ARCH_HAS_PREFETCHW
147 static inline void prefetchw(const void *ptr)
148 {
149 	asm volatile("prfm pstl1keep, %a0\n" : : "p" (ptr));
150 }
151 
152 #define ARCH_HAS_SPINLOCK_PREFETCH
153 static inline void spin_lock_prefetch(const void *x)
154 {
155 	prefetchw(x);
156 }
157 
158 #define HAVE_ARCH_PICK_MMAP_LAYOUT
159 
160 #endif
161 
162 #endif /* __ASM_PROCESSOR_H */
163