kernel/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 /* linux/smp.h <- linux/irqflags.h needs asm/smp.h first */
  17 #include <asm/smp.h>
  18
  19 /*
  20  * interrupt control
  21  * - "disabled": run in IM1/2
  22  *   - level 0 - kernel debugger
  23  *   - level 1 - virtual serial DMA (if present)
  24  *   - level 5 - normal interrupt priority
  25  *   - level 6 - timer interrupt
  26  * - "enabled":  run in IM7
  27  */
  28 #define MN10300_CLI_LEVEL       (CONFIG_LINUX_CLI_LEVEL << EPSW_IM_SHIFT)
  29
  30 #ifndef __ASSEMBLY__
  31
  32 static inline unsigned long arch_local_save_flags(void)
  33 {
  34         unsigned long flags;
  35
  36         asm volatile("mov epsw,%0" : "=d"(flags));
  37         return flags;
  38 }
  39
  40 static inline void arch_local_irq_disable(void)
  41 {
  42         asm volatile(
  43                 "       and %0,epsw     \n"
  44                 "       or %1,epsw      \n"
  45                 "       nop             \n"
  46                 "       nop             \n"
  47                 "       nop             \n"
  48                 :
  49                 : "i"(~EPSW_IM), "i"(EPSW_IE | MN10300_CLI_LEVEL)
  50                 : "memory");
  51 }
  52
  53 static inline unsigned long arch_local_irq_save(void)
  54 {
  55         unsigned long flags;
  56
  57         flags = arch_local_save_flags();
  58         arch_local_irq_disable();
  59         return flags;
  60 }
  61
  62 /*
  63  * we make sure arch_irq_enable() doesn't cause priority inversion
  64  */
  65 extern unsigned long __mn10300_irq_enabled_epsw[];
  66
  67 static inline void arch_local_irq_enable(void)
  68 {
  69         unsigned long tmp;
  70         int cpu = raw_smp_processor_id();
  71
  72         asm volatile(
  73                 "       mov     epsw,%0         \n"
  74                 "       and     %1,%0           \n"
  75                 "       or      %2,%0           \n"
  76                 "       mov     %0,epsw         \n"
  77                 : "=&d"(tmp)
  78                 : "i"(~EPSW_IM), "r"(__mn10300_irq_enabled_epsw[cpu])
  79                 : "memory", "cc");
  80 }
  81
  82 static inline void arch_local_irq_restore(unsigned long flags)
  83 {
  84         asm volatile(
  85                 "       mov %0,epsw     \n"
  86                 "       nop             \n"
  87                 "       nop             \n"
  88                 "       nop             \n"
  89                 :
  90                 : "d"(flags)
  91                 : "memory", "cc");
  92 }
  93
  94 static inline bool arch_irqs_disabled_flags(unsigned long flags)
  95 {
  96         return (flags & (EPSW_IE | EPSW_IM)) != (EPSW_IE | EPSW_IM_7);
  97 }
  98
  99 static inline bool arch_irqs_disabled(void)
 100 {
 101         return arch_irqs_disabled_flags(arch_local_save_flags());
 102 }
 103
 104 /*
 105  * Hook to save power by halting the CPU
 106  * - called from the idle loop
 107  * - must reenable interrupts (which takes three instruction cycles to complete)
 108  */
 109 static inline void arch_safe_halt(void)
 110 {
 111 #ifdef CONFIG_SMP
 112         arch_local_irq_enable();
 113 #else
 114         asm volatile(
 115                 "       or      %0,epsw \n"
 116                 "       nop             \n"
 117                 "       nop             \n"
 118                 "       bset    %2,(%1) \n"
 119                 :
 120                 : "i"(EPSW_IE|EPSW_IM), "n"(&CPUM), "i"(CPUM_SLEEP)
 121                 : "cc");
 122 #endif
 123 }
 124
 125 #define __sleep_cpu()                           \
 126 do {                                            \
 127         asm volatile(                           \
 128                 "       bset    %1,(%0)\n"      \
 129                 "1:     btst    %1,(%0)\n"      \
 130                 "       bne     1b\n"           \
 131                 :                               \
 132                 : "i"(&CPUM), "i"(CPUM_SLEEP)   \
 133                 : "cc"                          \
 134                 );                              \
 135 } while (0)
 136
 137 static inline void arch_local_cli(void)
 138 {
 139         asm volatile(
 140                 "       and     %0,epsw         \n"
 141                 "       nop                     \n"
 142                 "       nop                     \n"
 143                 "       nop                     \n"
 144                 :
 145                 : "i"(~EPSW_IE)
 146                 : "memory"
 147                 );
 148 }
 149
 150 static inline unsigned long arch_local_cli_save(void)
 151 {
 152         unsigned long flags = arch_local_save_flags();
 153         arch_local_cli();
 154         return flags;
 155 }
 156
 157 static inline void arch_local_sti(void)
 158 {
 159         asm volatile(
 160                 "       or      %0,epsw         \n"
 161                 :
 162                 : "i"(EPSW_IE)
 163                 : "memory");
 164 }
 165
 166 static inline void arch_local_change_intr_mask_level(unsigned long level)
 167 {
 168         asm volatile(
 169                 "       and     %0,epsw         \n"
 170                 "       or      %1,epsw         \n"
 171                 :
 172                 : "i"(~EPSW_IM), "i"(EPSW_IE | level)
 173                 : "cc", "memory");
 174 }
 175
 176 #else /* !__ASSEMBLY__ */
 177
 178 #define LOCAL_SAVE_FLAGS(reg)                   \
 179         mov     epsw,reg
 180
 181 #define LOCAL_IRQ_DISABLE                               \
 182         and     ~EPSW_IM,epsw;                          \
 183         or      EPSW_IE|MN10300_CLI_LEVEL,epsw;         \
 184         nop;                                            \
 185         nop;                                            \
 186         nop
 187
 188 #define LOCAL_IRQ_ENABLE                \
 189         or      EPSW_IE|EPSW_IM_7,epsw
 190
 191 #define LOCAL_IRQ_RESTORE(reg)  \
 192         mov     reg,epsw
 193
 194 #define LOCAL_CLI_SAVE(reg)     \
 195         mov     epsw,reg;       \
 196         and     ~EPSW_IE,epsw;  \
 197         nop;                    \
 198         nop;                    \
 199         nop
 200
 201 #define LOCAL_CLI               \
 202         and     ~EPSW_IE,epsw;  \
 203         nop;                    \
 204         nop;                    \
 205         nop
 206
 207 #define LOCAL_STI               \
 208         or      EPSW_IE,epsw
 209
 210 #define LOCAL_CHANGE_INTR_MASK_LEVEL(level)     \
 211         and     ~EPSW_IM,epsw;                  \
 212         or      EPSW_IE|(level),epsw
 213
 214 #endif /* __ASSEMBLY__ */
 215 #endif /* _ASM_IRQFLAGS_H */