Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame^] | 1 | /* |
| 2 | * include/asm-v850/system.h -- Low-level interrupt/thread ops |
| 3 | * |
| 4 | * Copyright (C) 2001,02,03 NEC Electronics Corporation |
| 5 | * Copyright (C) 2001,02,03 Miles Bader <miles@gnu.org> |
| 6 | * |
| 7 | * This file is subject to the terms and conditions of the GNU General |
| 8 | * Public License. See the file COPYING in the main directory of this |
| 9 | * archive for more details. |
| 10 | * |
| 11 | * Written by Miles Bader <miles@gnu.org> |
| 12 | */ |
| 13 | |
| 14 | #ifndef __V850_SYSTEM_H__ |
| 15 | #define __V850_SYSTEM_H__ |
| 16 | |
| 17 | #include <linux/linkage.h> |
| 18 | #include <asm/ptrace.h> |
| 19 | |
| 20 | |
| 21 | #define prepare_to_switch() do { } while (0) |
| 22 | |
| 23 | /* |
| 24 | * switch_to(n) should switch tasks to task ptr, first checking that |
| 25 | * ptr isn't the current task, in which case it does nothing. |
| 26 | */ |
| 27 | struct thread_struct; |
| 28 | extern void *switch_thread (struct thread_struct *last, |
| 29 | struct thread_struct *next); |
| 30 | #define switch_to(prev,next,last) \ |
| 31 | do { \ |
| 32 | if (prev != next) { \ |
| 33 | (last) = switch_thread (&prev->thread, &next->thread); \ |
| 34 | } \ |
| 35 | } while (0) |
| 36 | |
| 37 | |
| 38 | /* Enable/disable interrupts. */ |
| 39 | #define local_irq_enable() __asm__ __volatile__ ("ei") |
| 40 | #define local_irq_disable() __asm__ __volatile__ ("di") |
| 41 | |
| 42 | #define local_save_flags(flags) \ |
| 43 | __asm__ __volatile__ ("stsr %1, %0" : "=r" (flags) : "i" (SR_PSW)) |
| 44 | #define local_restore_flags(flags) \ |
| 45 | __asm__ __volatile__ ("ldsr %0, %1" :: "r" (flags), "i" (SR_PSW)) |
| 46 | |
| 47 | /* For spinlocks etc */ |
| 48 | #define local_irq_save(flags) \ |
| 49 | do { local_save_flags (flags); local_irq_disable (); } while (0) |
| 50 | #define local_irq_restore(flags) \ |
| 51 | local_restore_flags (flags); |
| 52 | |
| 53 | |
| 54 | static inline int irqs_disabled (void) |
| 55 | { |
| 56 | unsigned flags; |
| 57 | local_save_flags (flags); |
| 58 | return !!(flags & 0x20); |
| 59 | } |
| 60 | |
| 61 | |
| 62 | /* |
| 63 | * Force strict CPU ordering. |
| 64 | * Not really required on v850... |
| 65 | */ |
| 66 | #define nop() __asm__ __volatile__ ("nop") |
| 67 | #define mb() __asm__ __volatile__ ("" ::: "memory") |
| 68 | #define rmb() mb () |
| 69 | #define wmb() mb () |
| 70 | #define read_barrier_depends() ((void)0) |
| 71 | #define set_rmb(var, value) do { xchg (&var, value); } while (0) |
| 72 | #define set_mb(var, value) set_rmb (var, value) |
| 73 | #define set_wmb(var, value) do { var = value; wmb (); } while (0) |
| 74 | |
| 75 | #define smp_mb() mb () |
| 76 | #define smp_rmb() rmb () |
| 77 | #define smp_wmb() wmb () |
| 78 | #define smp_read_barrier_depends() read_barrier_depends() |
| 79 | |
| 80 | #define xchg(ptr, with) \ |
| 81 | ((__typeof__ (*(ptr)))__xchg ((unsigned long)(with), (ptr), sizeof (*(ptr)))) |
| 82 | #define tas(ptr) (xchg ((ptr), 1)) |
| 83 | |
| 84 | extern inline unsigned long __xchg (unsigned long with, |
| 85 | __volatile__ void *ptr, int size) |
| 86 | { |
| 87 | unsigned long tmp, flags; |
| 88 | |
| 89 | local_irq_save (flags); |
| 90 | |
| 91 | switch (size) { |
| 92 | case 1: |
| 93 | tmp = *(unsigned char *)ptr; |
| 94 | *(unsigned char *)ptr = with; |
| 95 | break; |
| 96 | case 2: |
| 97 | tmp = *(unsigned short *)ptr; |
| 98 | *(unsigned short *)ptr = with; |
| 99 | break; |
| 100 | case 4: |
| 101 | tmp = *(unsigned long *)ptr; |
| 102 | *(unsigned long *)ptr = with; |
| 103 | break; |
| 104 | } |
| 105 | |
| 106 | local_irq_restore (flags); |
| 107 | |
| 108 | return tmp; |
| 109 | } |
| 110 | |
| 111 | #define arch_align_stack(x) (x) |
| 112 | |
| 113 | #endif /* __V850_SYSTEM_H__ */ |