63d3850db224a0f630d6328637edd11410cc476f
[muen/linux.git] / arch / arm64 / include / asm / processor.h
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 #define TASK_SIZE_64            (UL(1) << VA_BITS)
23
24 #define KERNEL_DS       UL(-1)
25 #define USER_DS         (TASK_SIZE_64 - 1)
26
27 #ifndef __ASSEMBLY__
28
29 /*
30  * Default implementation of macro that returns current
31  * instruction pointer ("program counter").
32  */
33 #define current_text_addr() ({ __label__ _l; _l: &&_l;})
34
35 #ifdef __KERNEL__
36
37 #include <linux/string.h>
38
39 #include <asm/alternative.h>
40 #include <asm/cpufeature.h>
41 #include <asm/hw_breakpoint.h>
42 #include <asm/lse.h>
43 #include <asm/pgtable-hwdef.h>
44 #include <asm/ptrace.h>
45 #include <asm/types.h>
46
47 /*
48  * TASK_SIZE - the maximum size of a user space task.
49  * TASK_UNMAPPED_BASE - the lower boundary of the mmap VM area.
50  */
51 #ifdef CONFIG_COMPAT
52 #define TASK_SIZE_32            UL(0x100000000)
53 #define TASK_SIZE               (test_thread_flag(TIF_32BIT) ? \
54                                 TASK_SIZE_32 : TASK_SIZE_64)
55 #define TASK_SIZE_OF(tsk)       (test_tsk_thread_flag(tsk, TIF_32BIT) ? \
56                                 TASK_SIZE_32 : TASK_SIZE_64)
57 #else
58 #define TASK_SIZE               TASK_SIZE_64
59 #endif /* CONFIG_COMPAT */
60
61 #define TASK_UNMAPPED_BASE      (PAGE_ALIGN(TASK_SIZE / 4))
62
63 #define STACK_TOP_MAX           TASK_SIZE_64
64 #ifdef CONFIG_COMPAT
65 #define AARCH32_VECTORS_BASE    0xffff0000
66 #define STACK_TOP               (test_thread_flag(TIF_32BIT) ? \
67                                 AARCH32_VECTORS_BASE : STACK_TOP_MAX)
68 #else
69 #define STACK_TOP               STACK_TOP_MAX
70 #endif /* CONFIG_COMPAT */
71
72 extern phys_addr_t arm64_dma_phys_limit;
73 #define ARCH_LOW_ADDRESS_LIMIT  (arm64_dma_phys_limit - 1)
74
75 struct debug_info {
76 #ifdef CONFIG_HAVE_HW_BREAKPOINT
77         /* Have we suspended stepping by a debugger? */
78         int                     suspended_step;
79         /* Allow breakpoints and watchpoints to be disabled for this thread. */
80         int                     bps_disabled;
81         int                     wps_disabled;
82         /* Hardware breakpoints pinned to this task. */
83         struct perf_event       *hbp_break[ARM_MAX_BRP];
84         struct perf_event       *hbp_watch[ARM_MAX_WRP];
85 #endif
86 };
87
88 struct cpu_context {
89         unsigned long x19;
90         unsigned long x20;
91         unsigned long x21;
92         unsigned long x22;
93         unsigned long x23;
94         unsigned long x24;
95         unsigned long x25;
96         unsigned long x26;
97         unsigned long x27;
98         unsigned long x28;
99         unsigned long fp;
100         unsigned long sp;
101         unsigned long pc;
102 };
103
104 struct thread_struct {
105         struct cpu_context      cpu_context;    /* cpu context */
106         unsigned long           tp_value;       /* TLS register */
107 #ifdef CONFIG_COMPAT
108         unsigned long           tp2_value;
109 #endif
110         struct user_fpsimd_state fpsimd_state;
111         unsigned int            fpsimd_cpu;
112         void                    *sve_state;     /* SVE registers, if any */
113         unsigned int            sve_vl;         /* SVE vector length */
114         unsigned int            sve_vl_onexec;  /* SVE vl after next exec */
115         unsigned long           fault_address;  /* fault info */
116         unsigned long           fault_code;     /* ESR_EL1 value */
117         struct debug_info       debug;          /* debugging */
118 };
119
120 /*
121  * Everything usercopied to/from thread_struct is statically-sized, so
122  * no hardened usercopy whitelist is needed.
123  */
124 static inline void arch_thread_struct_whitelist(unsigned long *offset,
125                                                 unsigned long *size)
126 {
127         *offset = *size = 0;
128 }
129
130 #ifdef CONFIG_COMPAT
131 #define task_user_tls(t)                                                \
132 ({                                                                      \
133         unsigned long *__tls;                                           \
134         if (is_compat_thread(task_thread_info(t)))                      \
135                 __tls = &(t)->thread.tp2_value;                         \
136         else                                                            \
137                 __tls = &(t)->thread.tp_value;                          \
138         __tls;                                                          \
139  })
140 #else
141 #define task_user_tls(t)        (&(t)->thread.tp_value)
142 #endif
143
144 /* Sync TPIDR_EL0 back to thread_struct for current */
145 void tls_preserve_current_state(void);
146
147 #define INIT_THREAD  {  }
148
149 static inline void start_thread_common(struct pt_regs *regs, unsigned long pc)
150 {
151         memset(regs, 0, sizeof(*regs));
152         forget_syscall(regs);
153         regs->pc = pc;
154 }
155
156 static inline void start_thread(struct pt_regs *regs, unsigned long pc,
157                                 unsigned long sp)
158 {
159         start_thread_common(regs, pc);
160         regs->pstate = PSR_MODE_EL0t;
161         regs->sp = sp;
162 }
163
164 #ifdef CONFIG_COMPAT
165 static inline void compat_start_thread(struct pt_regs *regs, unsigned long pc,
166                                        unsigned long sp)
167 {
168         start_thread_common(regs, pc);
169         regs->pstate = COMPAT_PSR_MODE_USR;
170         if (pc & 1)
171                 regs->pstate |= COMPAT_PSR_T_BIT;
172
173 #ifdef __AARCH64EB__
174         regs->pstate |= COMPAT_PSR_E_BIT;
175 #endif
176
177         regs->compat_sp = sp;
178 }
179 #endif
180
181 /* Forward declaration, a strange C thing */
182 struct task_struct;
183
184 /* Free all resources held by a thread. */
185 extern void release_thread(struct task_struct *);
186
187 unsigned long get_wchan(struct task_struct *p);
188
189 static inline void cpu_relax(void)
190 {
191         asm volatile("yield" ::: "memory");
192 }
193
194 /* Thread switching */
195 extern struct task_struct *cpu_switch_to(struct task_struct *prev,
196                                          struct task_struct *next);
197
198 #define task_pt_regs(p) \
199         ((struct pt_regs *)(THREAD_SIZE + task_stack_page(p)) - 1)
200
201 #define KSTK_EIP(tsk)   ((unsigned long)task_pt_regs(tsk)->pc)
202 #define KSTK_ESP(tsk)   user_stack_pointer(task_pt_regs(tsk))
203
204 /*
205  * Prefetching support
206  */
207 #define ARCH_HAS_PREFETCH
208 static inline void prefetch(const void *ptr)
209 {
210         asm volatile("prfm pldl1keep, %a0\n" : : "p" (ptr));
211 }
212
213 #define ARCH_HAS_PREFETCHW
214 static inline void prefetchw(const void *ptr)
215 {
216         asm volatile("prfm pstl1keep, %a0\n" : : "p" (ptr));
217 }
218
219 #define ARCH_HAS_SPINLOCK_PREFETCH
220 static inline void spin_lock_prefetch(const void *ptr)
221 {
222         asm volatile(ARM64_LSE_ATOMIC_INSN(
223                      "prfm pstl1strm, %a0",
224                      "nop") : : "p" (ptr));
225 }
226
227 #define HAVE_ARCH_PICK_MMAP_LAYOUT
228
229 #endif
230
231 void cpu_enable_pan(const struct arm64_cpu_capabilities *__unused);
232 void cpu_enable_cache_maint_trap(const struct arm64_cpu_capabilities *__unused);
233 void cpu_clear_disr(const struct arm64_cpu_capabilities *__unused);
234
235 /* Userspace interface for PR_SVE_{SET,GET}_VL prctl()s: */
236 #define SVE_SET_VL(arg) sve_set_current_vl(arg)
237 #define SVE_GET_VL()    sve_get_current_vl()
238
239 #endif /* __ASSEMBLY__ */
240 #endif /* __ASM_PROCESSOR_H */