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 /*
  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/alternative.h>
  33 #include <asm/fpsimd.h>
  34 #include <asm/hw_breakpoint.h>
  35 #include <asm/lse.h>
  36 #include <asm/pgtable-hwdef.h>
  37 #include <asm/ptrace.h>
  38 #include <asm/types.h>
  39
  40 #ifdef __KERNEL__
  41 #define STACK_TOP_MAX           TASK_SIZE_64
  42 #ifdef CONFIG_COMPAT
  43 #define AARCH32_VECTORS_BASE    0xffff0000
  44 #define STACK_TOP               (test_thread_flag(TIF_32BIT) ? \
  45                                 AARCH32_VECTORS_BASE : STACK_TOP_MAX)
  46 #else
  47 #define STACK_TOP               STACK_TOP_MAX
  48 #endif /* CONFIG_COMPAT */
  49
  50 extern phys_addr_t arm64_dma_phys_limit;
  51 #define ARCH_LOW_ADDRESS_LIMIT  (arm64_dma_phys_limit - 1)
  52 #endif /* __KERNEL__ */
  53
  54 struct debug_info {
  55         /* Have we suspended stepping by a debugger? */
  56         int                     suspended_step;
  57         /* Allow breakpoints and watchpoints to be disabled for this thread. */
  58         int                     bps_disabled;
  59         int                     wps_disabled;
  60         /* Hardware breakpoints pinned to this task. */
  61         struct perf_event       *hbp_break[ARM_MAX_BRP];
  62         struct perf_event       *hbp_watch[ARM_MAX_WRP];
  63 };
  64
  65 struct cpu_context {
  66         unsigned long x19;
  67         unsigned long x20;
  68         unsigned long x21;
  69         unsigned long x22;
  70         unsigned long x23;
  71         unsigned long x24;
  72         unsigned long x25;
  73         unsigned long x26;
  74         unsigned long x27;
  75         unsigned long x28;
  76         unsigned long fp;
  77         unsigned long sp;
  78         unsigned long pc;
  79 };
  80
  81 struct thread_struct {
  82         struct cpu_context      cpu_context;    /* cpu context */
  83         unsigned long           tp_value;       /* TLS register */
  84 #ifdef CONFIG_COMPAT
  85         unsigned long           tp2_value;
  86 #endif
  87         struct fpsimd_state     fpsimd_state;
  88         unsigned long           fault_address;  /* fault info */
  89         unsigned long           fault_code;     /* ESR_EL1 value */
  90         struct debug_info       debug;          /* debugging */
  91 };
  92
  93 #ifdef CONFIG_COMPAT
  94 #define task_user_tls(t)                                                \
  95 ({                                                                      \
  96         unsigned long *__tls;                                           \
  97         if (is_compat_thread(task_thread_info(t)))                      \
  98                 __tls = &(t)->thread.tp2_value;                         \
  99         else                                                            \
 100                 __tls = &(t)->thread.tp_value;                          \
 101         __tls;                                                          \
 102  })
 103 #else
 104 #define task_user_tls(t)        (&(t)->thread.tp_value)
 105 #endif
 106
 107 #define INIT_THREAD  {  }
 108
 109 static inline void start_thread_common(struct pt_regs *regs, unsigned long pc)
 110 {
 111         memset(regs, 0, sizeof(*regs));
 112         regs->syscallno = ~0UL;
 113         regs->pc = pc;
 114 }
 115
 116 static inline void start_thread(struct pt_regs *regs, unsigned long pc,
 117                                 unsigned long sp)
 118 {
 119         start_thread_common(regs, pc);
 120         regs->pstate = PSR_MODE_EL0t;
 121         regs->sp = sp;
 122 }
 123
 124 #ifdef CONFIG_COMPAT
 125 static inline void compat_start_thread(struct pt_regs *regs, unsigned long pc,
 126                                        unsigned long sp)
 127 {
 128         start_thread_common(regs, pc);
 129         regs->pstate = COMPAT_PSR_MODE_USR;
 130         if (pc & 1)
 131                 regs->pstate |= COMPAT_PSR_T_BIT;
 132
 133 #ifdef __AARCH64EB__
 134         regs->pstate |= COMPAT_PSR_E_BIT;
 135 #endif
 136
 137         regs->compat_sp = sp;
 138 }
 139 #endif
 140
 141 /* Forward declaration, a strange C thing */
 142 struct task_struct;
 143
 144 /* Free all resources held by a thread. */
 145 extern void release_thread(struct task_struct *);
 146
 147 unsigned long get_wchan(struct task_struct *p);
 148
 149 static inline void cpu_relax(void)
 150 {
 151         asm volatile("yield" ::: "memory");
 152 }
 153
 154 #define cpu_relax_lowlatency()                cpu_relax()
 155
 156 /* Thread switching */
 157 extern struct task_struct *cpu_switch_to(struct task_struct *prev,
 158                                          struct task_struct *next);
 159
 160 #define task_pt_regs(p) \
 161         ((struct pt_regs *)(THREAD_START_SP + task_stack_page(p)) - 1)
 162
 163 #define KSTK_EIP(tsk)   ((unsigned long)task_pt_regs(tsk)->pc)
 164 #define KSTK_ESP(tsk)   user_stack_pointer(task_pt_regs(tsk))
 165
 166 /*
 167  * Prefetching support
 168  */
 169 #define ARCH_HAS_PREFETCH
 170 static inline void prefetch(const void *ptr)
 171 {
 172         asm volatile("prfm pldl1keep, %a0\n" : : "p" (ptr));
 173 }
 174
 175 #define ARCH_HAS_PREFETCHW
 176 static inline void prefetchw(const void *ptr)
 177 {
 178         asm volatile("prfm pstl1keep, %a0\n" : : "p" (ptr));
 179 }
 180
 181 #define ARCH_HAS_SPINLOCK_PREFETCH
 182 static inline void spin_lock_prefetch(const void *ptr)
 183 {
 184         asm volatile(ARM64_LSE_ATOMIC_INSN(
 185                      "prfm pstl1strm, %a0",
 186                      "nop") : : "p" (ptr));
 187 }
 188
 189 #define HAVE_ARCH_PICK_MMAP_LAYOUT
 190
 191 #endif
 192
 193 void cpu_enable_pan(void *__unused);
 194 void cpu_enable_uao(void *__unused);
 195 void cpu_enable_cache_maint_trap(void *__unused);
 196
 197 #endif /* __ASM_PROCESSOR_H */