include/asm/processor.h

0001 /* SPDX-License-Identifier: GPL-2.0-only */
0002 /*
0003  *  arch/arm/include/asm/processor.h
0004  *
0005  *  Copyright (C) 1995-1999 Russell King
0006  */
0007
0008 #ifndef __ASM_ARM_PROCESSOR_H
0009 #define __ASM_ARM_PROCESSOR_H
0010
0011 #ifdef __KERNEL__
0012
0013 #include <asm/hw_breakpoint.h>
0014 #include <asm/ptrace.h>
0015 #include <asm/types.h>
0016 #include <asm/unified.h>
0017 #include <asm/vdso/processor.h>
0018
0019 #ifdef __KERNEL__
0020 #define STACK_TOP   ((current->personality & ADDR_LIMIT_32BIT) ? \
0021              TASK_SIZE : TASK_SIZE_26)
0022 #define STACK_TOP_MAX   TASK_SIZE
0023 #endif
0024
0025 struct debug_info {
0026 #ifdef CONFIG_HAVE_HW_BREAKPOINT
0027     struct perf_event   *hbp[ARM_MAX_HBP_SLOTS];
0028 #endif
0029 };
0030
0031 struct thread_struct {
0032                             /* fault info     */
0033     unsigned long       address;
0034     unsigned long       trap_no;
0035     unsigned long       error_code;
0036                             /* debugging      */
0037     struct debug_info   debug;
0038 };
0039
0040 /*
0041  * Everything usercopied to/from thread_struct is statically-sized, so
0042  * no hardened usercopy whitelist is needed.
0043  */
0044 static inline void arch_thread_struct_whitelist(unsigned long *offset,
0045                         unsigned long *size)
0046 {
0047     *offset = *size = 0;
0048 }
0049
0050 #define INIT_THREAD  {  }
0051
0052 #define start_thread(regs,pc,sp)                    \
0053 ({                                  \
0054     unsigned long r7, r8, r9;                   \
0055                                     \
0056     if (IS_ENABLED(CONFIG_BINFMT_ELF_FDPIC)) {          \
0057         r7 = regs->ARM_r7;                  \
0058         r8 = regs->ARM_r8;                  \
0059         r9 = regs->ARM_r9;                  \
0060     }                               \
0061     memset(regs->uregs, 0, sizeof(regs->uregs));            \
0062     if (IS_ENABLED(CONFIG_BINFMT_ELF_FDPIC) &&          \
0063         current->personality & FDPIC_FUNCPTRS) {            \
0064         regs->ARM_r7 = r7;                  \
0065         regs->ARM_r8 = r8;                  \
0066         regs->ARM_r9 = r9;                  \
0067         regs->ARM_r10 = current->mm->start_data;        \
0068     } else if (!IS_ENABLED(CONFIG_MMU))             \
0069         regs->ARM_r10 = current->mm->start_data;        \
0070     if (current->personality & ADDR_LIMIT_32BIT)            \
0071         regs->ARM_cpsr = USR_MODE;              \
0072     else                                \
0073         regs->ARM_cpsr = USR26_MODE;                \
0074     if (elf_hwcap & HWCAP_THUMB && pc & 1)              \
0075         regs->ARM_cpsr |= PSR_T_BIT;                \
0076     regs->ARM_cpsr |= PSR_ENDSTATE;                 \
0077     regs->ARM_pc = pc & ~1;     /* pc */            \
0078     regs->ARM_sp = sp;      /* sp */            \
0079 })
0080
0081 /* Forward declaration, a strange C thing */
0082 struct task_struct;
0083
0084 /* Free all resources held by a thread. */
0085 extern void release_thread(struct task_struct *);
0086
0087 unsigned long __get_wchan(struct task_struct *p);
0088
0089 #define task_pt_regs(p) \
0090     ((struct pt_regs *)(THREAD_START_SP + task_stack_page(p)) - 1)
0091
0092 #define KSTK_EIP(tsk)   task_pt_regs(tsk)->ARM_pc
0093 #define KSTK_ESP(tsk)   task_pt_regs(tsk)->ARM_sp
0094
0095 #ifdef CONFIG_SMP
0096 #define __ALT_SMP_ASM(smp, up)                      \
0097     "9998:  " smp "\n"                      \
0098     "   .pushsection \".alt.smp.init\", \"a\"\n"        \
0099     "   .align  2\n"                        \
0100     "   .long   9998b - .\n"                    \
0101     "   " up "\n"                       \
0102     "   .popsection\n"
0103 #else
0104 #define __ALT_SMP_ASM(smp, up)  up
0105 #endif
0106
0107 /*
0108  * Prefetching support - only ARMv5.
0109  */
0110 #if __LINUX_ARM_ARCH__ >= 5
0111
0112 #define ARCH_HAS_PREFETCH
0113 static inline void prefetch(const void *ptr)
0114 {
0115     __asm__ __volatile__(
0116         "pld\t%a0"
0117         :: "p" (ptr));
0118 }
0119
0120 #if __LINUX_ARM_ARCH__ >= 7 && defined(CONFIG_SMP)
0121 #define ARCH_HAS_PREFETCHW
0122 static inline void prefetchw(const void *ptr)
0123 {
0124     __asm__ __volatile__(
0125         ".arch_extension    mp\n"
0126         __ALT_SMP_ASM(
0127             "pldw\t%a0",
0128             "pld\t%a0"
0129         )
0130         :: "p" (ptr));
0131 }
0132 #endif
0133 #endif
0134
0135 #endif
0136
0137 #endif /* __ASM_ARM_PROCESSOR_H */