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