Linux-2.6.12-rc2
[linux-flexiantxendom0-natty.git] / include / asm-sh / system.h
1 #ifndef __ASM_SH_SYSTEM_H
2 #define __ASM_SH_SYSTEM_H
3
4 /*
5  * Copyright (C) 1999, 2000  Niibe Yutaka  &  Kaz Kojima
6  * Copyright (C) 2002 Paul Mundt
7  */
8
9 #include <linux/config.h>
10
11 /*
12  *      switch_to() should switch tasks to task nr n, first
13  */
14
15 #define switch_to(prev, next, last) do {                                \
16  task_t *__last;                                                        \
17  register unsigned long *__ts1 __asm__ ("r1") = &prev->thread.sp;       \
18  register unsigned long *__ts2 __asm__ ("r2") = &prev->thread.pc;       \
19  register unsigned long *__ts4 __asm__ ("r4") = (unsigned long *)prev;  \
20  register unsigned long *__ts5 __asm__ ("r5") = (unsigned long *)next;  \
21  register unsigned long *__ts6 __asm__ ("r6") = &next->thread.sp;       \
22  register unsigned long __ts7 __asm__ ("r7") = next->thread.pc;         \
23  __asm__ __volatile__ (".balign 4\n\t"                                  \
24                        "stc.l   gbr, @-r15\n\t"                         \
25                        "sts.l   pr, @-r15\n\t"                          \
26                        "mov.l   r8, @-r15\n\t"                          \
27                        "mov.l   r9, @-r15\n\t"                          \
28                        "mov.l   r10, @-r15\n\t"                         \
29                        "mov.l   r11, @-r15\n\t"                         \
30                        "mov.l   r12, @-r15\n\t"                         \
31                        "mov.l   r13, @-r15\n\t"                         \
32                        "mov.l   r14, @-r15\n\t"                         \
33                        "mov.l   r15, @r1        ! save SP\n\t"          \
34                        "mov.l   @r6, r15        ! change to new stack\n\t" \
35                        "mova    1f, %0\n\t"                             \
36                        "mov.l   %0, @r2         ! save PC\n\t"          \
37                        "mov.l   2f, %0\n\t"                             \
38                        "jmp     @%0             ! call __switch_to\n\t" \
39                        " lds    r7, pr          !  with return to new PC\n\t" \
40                        ".balign 4\n"                                    \
41                        "2:\n\t"                                         \
42                        ".long   __switch_to\n"                          \
43                        "1:\n\t"                                         \
44                        "mov.l   @r15+, r14\n\t"                         \
45                        "mov.l   @r15+, r13\n\t"                         \
46                        "mov.l   @r15+, r12\n\t"                         \
47                        "mov.l   @r15+, r11\n\t"                         \
48                        "mov.l   @r15+, r10\n\t"                         \
49                        "mov.l   @r15+, r9\n\t"                          \
50                        "mov.l   @r15+, r8\n\t"                          \
51                        "lds.l   @r15+, pr\n\t"                          \
52                        "ldc.l   @r15+, gbr\n\t"                         \
53                        : "=z" (__last)                                  \
54                        : "r" (__ts1), "r" (__ts2), "r" (__ts4),         \
55                          "r" (__ts5), "r" (__ts6), "r" (__ts7)          \
56                        : "r3", "t");                                    \
57         last = __last;                                                  \
58 } while (0)
59
60 #define nop() __asm__ __volatile__ ("nop")
61
62
63 #define xchg(ptr,x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))
64
65 static __inline__ unsigned long tas(volatile int *m)
66 { /* #define tas(ptr) (xchg((ptr),1)) */
67         unsigned long retval;
68
69         __asm__ __volatile__ ("tas.b    @%1\n\t"
70                               "movt     %0"
71                               : "=r" (retval): "r" (m): "t", "memory");
72         return retval;
73 }
74
75 extern void __xchg_called_with_bad_pointer(void);
76
77 #define mb()    __asm__ __volatile__ ("": : :"memory")
78 #define rmb()   mb()
79 #define wmb()   __asm__ __volatile__ ("": : :"memory")
80 #define read_barrier_depends()  do { } while(0)
81
82 #ifdef CONFIG_SMP
83 #define smp_mb()        mb()
84 #define smp_rmb()       rmb()
85 #define smp_wmb()       wmb()
86 #define smp_read_barrier_depends()      read_barrier_depends()
87 #else
88 #define smp_mb()        barrier()
89 #define smp_rmb()       barrier()
90 #define smp_wmb()       barrier()
91 #define smp_read_barrier_depends()      do { } while(0)
92 #endif
93
94 #define set_mb(var, value) do { xchg(&var, value); } while (0)
95 #define set_wmb(var, value) do { var = value; wmb(); } while (0)
96
97 /* Interrupt Control */
98 static __inline__ void local_irq_enable(void)
99 {
100         unsigned long __dummy0, __dummy1;
101
102         __asm__ __volatile__("stc       sr, %0\n\t"
103                              "and       %1, %0\n\t"
104                              "stc       r6_bank, %1\n\t"
105                              "or        %1, %0\n\t"
106                              "ldc       %0, sr"
107                              : "=&r" (__dummy0), "=r" (__dummy1)
108                              : "1" (~0x000000f0)
109                              : "memory");
110 }
111
112 static __inline__ void local_irq_disable(void)
113 {
114         unsigned long __dummy;
115         __asm__ __volatile__("stc       sr, %0\n\t"
116                              "or        #0xf0, %0\n\t"
117                              "ldc       %0, sr"
118                              : "=&z" (__dummy)
119                              : /* no inputs */
120                              : "memory");
121 }
122
123 #define local_save_flags(x) \
124         __asm__("stc sr, %0; and #0xf0, %0" : "=&z" (x) :/**/: "memory" )
125
126 #define irqs_disabled()                 \
127 ({                                      \
128         unsigned long flags;            \
129         local_save_flags(flags);        \
130         (flags != 0);                   \
131 })
132
133 static __inline__ unsigned long local_irq_save(void)
134 {
135         unsigned long flags, __dummy;
136
137         __asm__ __volatile__("stc       sr, %1\n\t"
138                              "mov       %1, %0\n\t"
139                              "or        #0xf0, %0\n\t"
140                              "ldc       %0, sr\n\t"
141                              "mov       %1, %0\n\t"
142                              "and       #0xf0, %0"
143                              : "=&z" (flags), "=&r" (__dummy)
144                              :/**/
145                              : "memory" );
146         return flags;
147 }
148
149 #ifdef DEBUG_CLI_STI
150 static __inline__ void  local_irq_restore(unsigned long x)
151 {
152         if ((x & 0x000000f0) != 0x000000f0)
153                 local_irq_enable();
154         else {
155                 unsigned long flags;
156                 local_save_flags(flags);
157
158                 if (flags == 0) {
159                         extern void dump_stack(void);
160                         printk(KERN_ERR "BUG!\n");
161                         dump_stack();
162                         local_irq_disable();
163                 }
164         }
165 }
166 #else
167 #define local_irq_restore(x) do {                       \
168         if ((x & 0x000000f0) != 0x000000f0)             \
169                 local_irq_enable();                             \
170 } while (0)
171 #endif
172
173 #define really_restore_flags(x) do {                    \
174         if ((x & 0x000000f0) != 0x000000f0)             \
175                 local_irq_enable();                             \
176         else                                            \
177                 local_irq_disable();                            \
178 } while (0)
179
180 /*
181  * Jump to P2 area.
182  * When handling TLB or caches, we need to do it from P2 area.
183  */
184 #define jump_to_P2()                    \
185 do {                                    \
186         unsigned long __dummy;          \
187         __asm__ __volatile__(           \
188                 "mov.l  1f, %0\n\t"     \
189                 "or     %1, %0\n\t"     \
190                 "jmp    @%0\n\t"        \
191                 " nop\n\t"              \
192                 ".balign 4\n"           \
193                 "1:     .long 2f\n"     \
194                 "2:"                    \
195                 : "=&r" (__dummy)       \
196                 : "r" (0x20000000));    \
197 } while (0)
198
199 /*
200  * Back to P1 area.
201  */
202 #define back_to_P1()                                    \
203 do {                                                    \
204         unsigned long __dummy;                          \
205         __asm__ __volatile__(                           \
206                 "nop;nop;nop;nop;nop;nop;nop\n\t"       \
207                 "mov.l  1f, %0\n\t"                     \
208                 "jmp    @%0\n\t"                        \
209                 " nop\n\t"                              \
210                 ".balign 4\n"                           \
211                 "1:     .long 2f\n"                     \
212                 "2:"                                    \
213                 : "=&r" (__dummy));                     \
214 } while (0)
215
216 /* For spinlocks etc */
217 #define local_irq_save(x)       x = local_irq_save()
218
219 static __inline__ unsigned long xchg_u32(volatile int * m, unsigned long val)
220 {
221         unsigned long flags, retval;
222
223         local_irq_save(flags);
224         retval = *m;
225         *m = val;
226         local_irq_restore(flags);
227         return retval;
228 }
229
230 static __inline__ unsigned long xchg_u8(volatile unsigned char * m, unsigned long val)
231 {
232         unsigned long flags, retval;
233
234         local_irq_save(flags);
235         retval = *m;
236         *m = val & 0xff;
237         local_irq_restore(flags);
238         return retval;
239 }
240
241 static __inline__ unsigned long __xchg(unsigned long x, volatile void * ptr, int size)
242 {
243         switch (size) {
244         case 4:
245                 return xchg_u32(ptr, x);
246                 break;
247         case 1:
248                 return xchg_u8(ptr, x);
249                 break;
250         }
251         __xchg_called_with_bad_pointer();
252         return x;
253 }
254
255 /* XXX
256  * disable hlt during certain critical i/o operations
257  */
258 #define HAVE_DISABLE_HLT
259 void disable_hlt(void);
260 void enable_hlt(void);
261
262 #define arch_align_stack(x) (x)
263
264 #endif