1 #ifndef __PPC64_SYSTEM_H
2 #define __PPC64_SYSTEM_H
3 
4 /*
5  * This program is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU General Public License
7  * as published by the Free Software Foundation; either version
8  * 2 of the License, or (at your option) any later version.
9  */
10 
11 #include <linux/config.h>
12 #include <linux/kdev_t.h>
13 #include <asm/page.h>
14 #include <asm/processor.h>
15 #include <asm/hw_irq.h>
16 #include <asm/memory.h>
17 
18 /*
19  * Memory barrier.
20  * The sync instruction guarantees that all memory accesses initiated
21  * by this processor have been performed (with respect to all other
22  * mechanisms that access memory).  The eieio instruction is a barrier
23  * providing an ordering (separately) for (a) cacheable stores and (b)
24  * loads and stores to non-cacheable memory (e.g. I/O devices).
25  *
26  * mb() prevents loads and stores being reordered across this point.
27  * rmb() prevents loads being reordered across this point.
28  * wmb() prevents stores being reordered across this point.
29  *
30  * We can use the eieio instruction for wmb, but since it doesn't
31  * give any ordering guarantees about loads, we have to use the
32  * stronger but slower sync instruction for mb and rmb.
33  */
34 #define mb()   __asm__ __volatile__ ("sync" : : : "memory")
35 #define rmb()  __asm__ __volatile__ ("lwsync" : : : "memory")
36 #define wmb()  __asm__ __volatile__ ("eieio" : : : "memory")
37 
38 #define set_mb(var, value)	do { var = value; mb(); } while (0)
39 #define set_wmb(var, value)	do { var = value; wmb(); } while (0)
40 
41 #ifdef CONFIG_SMP
42 #define smp_mb()	mb()
43 #define smp_rmb()	rmb()
44 #define smp_wmb()	wmb()
45 #else
46 #define smp_mb()	__asm__ __volatile__("": : :"memory")
47 #define smp_rmb()	__asm__ __volatile__("": : :"memory")
48 #define smp_wmb()	__asm__ __volatile__("": : :"memory")
49 #endif /* CONFIG_SMP */
50 
51 #ifdef CONFIG_XMON
52 extern void xmon_irq(int, void *, struct pt_regs *);
53 extern void xmon(struct pt_regs *excp);
54 #endif
55 
56 extern void print_backtrace(unsigned long *);
57 extern void show_regs(struct pt_regs * regs);
58 extern void flush_instruction_cache(void);
59 extern void hard_reset_now(void);
60 extern void poweroff_now(void);
61 extern int _get_PVR(void);
62 extern long _get_L2CR(void);
63 extern void _set_L2CR(unsigned long);
64 extern void giveup_fpu(struct task_struct *);
65 extern void enable_kernel_fp(void);
66 extern void giveup_altivec(struct task_struct *);
67 extern void load_up_altivec(struct task_struct *);
68 extern void cvt_fd(float *from, double *to, unsigned long *fpscr);
69 extern void cvt_df(double *from, float *to, unsigned long *fpscr);
70 extern int abs(int);
71 extern void cacheable_memzero(void *p, unsigned int nb);
72 extern void vpa_init(int cpu);
73 
74 struct device_node;
75 
76 struct task_struct;
77 #define prepare_to_switch()	do { } while(0)
78 #define switch_to(prev,next,last) _switch_to((prev),(next),&(last))
79 extern void _switch_to(struct task_struct *, struct task_struct *,
80 		       struct task_struct **);
81 
82 struct thread_struct;
83 extern struct task_struct *_switch(struct thread_struct *prev,
84 				   struct thread_struct *next);
85 
86 struct pt_regs;
87 extern void dump_regs(struct pt_regs *);
88 
89 #ifndef CONFIG_SMP
90 
91 #define cli()	__cli()
92 #define sti()	__sti()
93 #define save_flags(flags)	__save_flags(flags)
94 #define restore_flags(flags)	__restore_flags(flags)
95 #define save_and_cli(flags)	__save_and_cli(flags)
96 #define save_and_sti(flags)	__save_and_sti(flags)
97 
98 #else /* CONFIG_SMP */
99 
100 extern void __global_cli(void);
101 extern void __global_sti(void);
102 extern unsigned long __global_save_flags(void);
103 extern void __global_restore_flags(unsigned long);
104 #define cli() __global_cli()
105 #define sti() __global_sti()
106 #define save_flags(x) ((x)=__global_save_flags())
107 #define restore_flags(x) __global_restore_flags(x)
108 
109 #define save_and_cli(x) do { save_flags(x); cli(); } while(0);
110 #define save_and_sti(x) do { save_flags(x); sti(); } while(0);
111 
112 #endif /* !CONFIG_SMP */
113 
114 #define local_irq_disable()		__cli()
115 #define local_irq_enable()		__sti()
116 #define local_irq_save(flags)		__save_and_cli(flags)
117 #define local_irq_set(flags)		__save_and_sti(flags)
118 #define local_irq_restore(flags)	__restore_flags(flags)
119 
__is_processor(unsigned long pv)120 static __inline__ int __is_processor(unsigned long pv)
121 {
122       unsigned long pvr;
123       asm volatile("mfspr %0, 0x11F" : "=r" (pvr));
124       return(PVR_VER(pvr) == pv);
125 }
126 
127 /*
128  * Atomic exchange
129  *
130  * Changes the memory location '*ptr' to be val and returns
131  * the previous value stored there.
132  *
133  * Inline asm pulled from arch/ppc/kernel/misc.S so ppc64
134  * is more like most of the other architectures.
135  */
136 static __inline__ unsigned long
__xchg_u32(volatile int * m,unsigned long val)137 __xchg_u32(volatile int *m, unsigned long val)
138 {
139 	unsigned long dummy;
140 
141 	__asm__ __volatile__(
142 	EIEIO_ON_SMP
143 "1:	lwarx %0,0,%3		# __xchg_u32\n\
144 	stwcx. %2,0,%3\n\
145 2:	bne- 1b"
146 	ISYNC_ON_SMP
147  	: "=&r" (dummy), "=m" (*m)
148 	: "r" (val), "r" (m)
149 	: "cc", "memory");
150 
151 	return (dummy);
152 }
153 
154 static __inline__ unsigned long
__xchg_u64(volatile long * m,unsigned long val)155 __xchg_u64(volatile long *m, unsigned long val)
156 {
157 	unsigned long dummy;
158 
159 	__asm__ __volatile__(
160 	EIEIO_ON_SMP
161 "1:	ldarx %0,0,%3		# __xchg_u64\n\
162 	stdcx. %2,0,%3\n\
163 2:	bne- 1b"
164 	ISYNC_ON_SMP
165 	: "=&r" (dummy), "=m" (*m)
166 	: "r" (val), "r" (m)
167 	: "cc", "memory");
168 
169 	return (dummy);
170 }
171 
172 /*
173  * This function doesn't exist, so you'll get a linker error
174  * if something tries to do an invalid xchg().
175  */
176 extern void __xchg_called_with_bad_pointer(void);
177 
178 static __inline__ unsigned long
__xchg(volatile void * ptr,unsigned long x,int size)179 __xchg(volatile void *ptr, unsigned long x, int size)
180 {
181 	switch (size) {
182 	case 4:
183 		return __xchg_u32(ptr, x);
184 	case 8:
185 		return __xchg_u64(ptr, x);
186 	}
187 	__xchg_called_with_bad_pointer();
188 	return x;
189 }
190 
191 #define xchg(ptr,x)							     \
192   ({									     \
193      __typeof__(*(ptr)) _x_ = (x);					     \
194      (__typeof__(*(ptr))) __xchg((ptr), (unsigned long)_x_, sizeof(*(ptr))); \
195   })
196 
197 #define tas(ptr) (xchg((ptr),1))
198 
199 #define __HAVE_ARCH_CMPXCHG	1
200 
201 static __inline__ unsigned long
__cmpxchg_u32(volatile int * p,int old,int new)202 __cmpxchg_u32(volatile int *p, int old, int new)
203 {
204 	int prev;
205 
206 	__asm__ __volatile__ (
207 	EIEIO_ON_SMP
208 "1:	lwarx	%0,0,%2		# __cmpxchg_u32\n\
209 	cmpw	0,%0,%3\n\
210 	bne-	2f\n\
211 	stwcx.	%4,0,%2\n\
212 	bne-	1b"
213 	ISYNC_ON_SMP
214 	"\n\
215 2:"
216 	: "=&r" (prev), "=m" (*p)
217 	: "r" (p), "r" (old), "r" (new), "m" (*p)
218 	: "cc", "memory");
219 
220 	return prev;
221 }
222 
223 static __inline__ unsigned long
__cmpxchg_u64(volatile long * p,unsigned long old,unsigned long new)224 __cmpxchg_u64(volatile long *p, unsigned long old, unsigned long new)
225 {
226 	int prev;
227 
228 	__asm__ __volatile__ (
229 	EIEIO_ON_SMP
230 "1:	ldarx	%0,0,%2		# __cmpxchg_u64\n\
231 	cmpd	0,%0,%3\n\
232 	bne-	2f\n\
233 	stdcx.	%4,0,%2\n\
234 	bne-	1b"
235 	ISYNC_ON_SMP
236 	"\n\
237 2:"
238 	: "=&r" (prev), "=m" (*p)
239 	: "r" (p), "r" (old), "r" (new), "m" (*p)
240 	: "cc", "memory");
241 
242 	return prev;
243 }
244 
245 /* This function doesn't exist, so you'll get a linker error
246    if something tries to do an invalid cmpxchg().  */
247 extern void __cmpxchg_called_with_bad_pointer(void);
248 
249 static __inline__ unsigned long
__cmpxchg(volatile void * ptr,unsigned long old,unsigned long new,int size)250 __cmpxchg(volatile void *ptr, unsigned long old, unsigned long new, int size)
251 {
252 	switch (size) {
253 	case 4:
254 		return __cmpxchg_u32(ptr, old, new);
255 	case 8:
256 		return __cmpxchg_u64(ptr, old, new);
257 	}
258 	__cmpxchg_called_with_bad_pointer();
259 	return old;
260 }
261 
262 #define cmpxchg(ptr,o,n)						 \
263   ({									 \
264      __typeof__(*(ptr)) _o_ = (o);					 \
265      __typeof__(*(ptr)) _n_ = (n);					 \
266      (__typeof__(*(ptr))) __cmpxchg((ptr), (unsigned long)_o_,		 \
267 				    (unsigned long)_n_, sizeof(*(ptr))); \
268   })
269 
270 #endif
271