arch/mn10300/include/asm/irqflags.h

   1 /* MN10300 IRQ flag handling
   2  *
   3  * Copyright (C) 2010 Red Hat, Inc. All Rights Reserved.
   4  * Written by David Howells (dhowells@redhat.com)
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public Licence
   8  * as published by the Free Software Foundation; either version
   9  * 2 of the Licence, or (at your option) any later version.
  10  */
  11
  12 #ifndef _ASM_IRQFLAGS_H
  13 #define _ASM_IRQFLAGS_H
  14
  15 #include <asm/cpu-regs.h>
  16
  17 /*
  18  * interrupt control
  19  * - "disabled": run in IM1/2
  20  *   - level 0 - GDB stub
  21  *   - level 1 - virtual serial DMA (if present)
  22  *   - level 5 - normal interrupt priority
  23  *   - level 6 - timer interrupt
  24  * - "enabled":  run in IM7
  25  */
  26 #define MN10300_CLI_LEVEL       (CONFIG_LINUX_CLI_LEVEL << EPSW_IM_SHIFT)
  27
  28 #ifndef __ASSEMBLY__
  29
  30 static inline unsigned long arch_local_save_flags(void)
  31 {
  32         unsigned long flags;
  33
  34         asm volatile("mov epsw,%0" : "=d"(flags));
  35         return flags;
  36 }
  37
  38 static inline void arch_local_irq_disable(void)
  39 {
  40         asm volatile(
  41                 "       and %0,epsw     \n"
  42                 "       or %1,epsw      \n"
  43                 "       nop             \n"
  44                 "       nop             \n"
  45                 "       nop             \n"
  46                 :
  47                 : "i"(~EPSW_IM), "i"(EPSW_IE | MN10300_CLI_LEVEL)
  48                 : "memory");
  49 }
  50
  51 static inline unsigned long arch_local_irq_save(void)
  52 {
  53         unsigned long flags;
  54
  55         flags = arch_local_save_flags();
  56         arch_local_irq_disable();
  57         return flags;
  58 }
  59
  60 /*
  61  * we make sure arch_irq_enable() doesn't cause priority inversion
  62  */
  63 extern unsigned long __mn10300_irq_enabled_epsw;
  64
  65 static inline void arch_local_irq_enable(void)
  66 {
  67         unsigned long tmp;
  68
  69         asm volatile(
  70                 "       mov     epsw,%0         \n"
  71                 "       and     %1,%0           \n"
  72                 "       or      %2,%0           \n"
  73                 "       mov     %0,epsw         \n"
  74                 : "=&d"(tmp)
  75                 : "i"(~EPSW_IM), "r"(__mn10300_irq_enabled_epsw)
  76                 : "memory");
  77 }
  78
  79 static inline void arch_local_irq_restore(unsigned long flags)
  80 {
  81         asm volatile(
  82                 "       mov %0,epsw     \n"
  83                 "       nop             \n"
  84                 "       nop             \n"
  85                 "       nop             \n"
  86                 :
  87                 : "d"(flags)
  88                 : "memory", "cc");
  89 }
  90
  91 static inline bool arch_irqs_disabled_flags(unsigned long flags)
  92 {
  93         return (flags & (EPSW_IE | EPSW_IM)) != (EPSW_IE | EPSW_IM_7);
  94 }
  95
  96 static inline bool arch_irqs_disabled(void)
  97 {
  98         return arch_irqs_disabled_flags(arch_local_save_flags());
  99 }
 100
 101 /*
 102  * Hook to save power by halting the CPU
 103  * - called from the idle loop
 104  * - must reenable interrupts (which takes three instruction cycles to complete)
 105  */
 106 static inline void arch_safe_halt(void)
 107 {
 108         asm volatile(
 109                 "       or      %0,epsw \n"
 110                 "       nop             \n"
 111                 "       nop             \n"
 112                 "       bset    %2,(%1) \n"
 113                 :
 114                 : "i"(EPSW_IE|EPSW_IM), "n"(&CPUM), "i"(CPUM_SLEEP)
 115                 : "cc");
 116 }
 117
 118 static inline void arch_local_cli(void)
 119 {
 120         asm volatile(
 121                 "       and     %0,epsw         \n"
 122                 "       nop                     \n"
 123                 "       nop                     \n"
 124                 "       nop                     \n"
 125                 :
 126                 : "i"(~EPSW_IE)
 127                 : "memory"
 128                 );
 129 }
 130
 131 static inline unsigned long arch_local_cli_save(void)
 132 {
 133         unsigned long flags = arch_local_save_flags();
 134         arch_local_cli();
 135         return flags;
 136 }
 137
 138 static inline void arch_local_sti(void)
 139 {
 140         asm volatile(
 141                 "       or      %0,epsw         \n"
 142                 :
 143                 : "i"(EPSW_IE)
 144                 : "memory");
 145 }
 146
 147 static inline void arch_local_change_intr_mask_level(unsigned long level)
 148 {
 149         asm volatile(
 150                 "       and     %0,epsw         \n"
 151                 "       or      %1,epsw         \n"
 152                 :
 153                 : "i"(~EPSW_IM), "i"(EPSW_IE | level)
 154                 : "cc", "memory");
 155 }
 156
 157 #else /* !__ASSEMBLY__ */
 158
 159 #define LOCAL_SAVE_FLAGS(reg)                   \
 160         mov     epsw,reg
 161
 162 #define LOCAL_IRQ_DISABLE                               \
 163         and     ~EPSW_IM,epsw;                          \
 164         or      EPSW_IE|MN10300_CLI_LEVEL,epsw;         \
 165         nop;                                            \
 166         nop;                                            \
 167         nop
 168
 169 #define LOCAL_IRQ_ENABLE                \
 170         or      EPSW_IE|EPSW_IM_7,epsw
 171
 172 #define LOCAL_IRQ_RESTORE(reg)  \
 173         mov     reg,epsw
 174
 175 #define LOCAL_CLI_SAVE(reg)     \
 176         mov     epsw,reg;       \
 177         and     ~EPSW_IE,epsw;  \
 178         nop;                    \
 179         nop;                    \
 180         nop
 181
 182 #define LOCAL_CLI               \
 183         and     ~EPSW_IE,epsw;  \
 184         nop;                    \
 185         nop;                    \
 186         nop
 187
 188 #define LOCAL_STI               \
 189         or      EPSW_IE,epsw
 190
 191 #define LOCAL_CHANGE_INTR_MASK_LEVEL(level)     \
 192         and     ~EPSW_IM,epsw;                  \
 193         or      EPSW_IE|(level),epsw
 194
 195 #endif /* __ASSEMBLY__ */
 196 #endif /* _ASM_IRQFLAGS_H */