tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
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linux
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/compiler.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 * read_barrier_depends() prevents data-dependent loads being reordered
30 * across this point (nop on PPC).
31 *
32 * We have to use the sync instructions for mb(), since lwsync doesn't
33 * order loads with respect to previous stores. Lwsync is fine for
34 * rmb(), though.
35 * For wmb(), we use sync since wmb is used in drivers to order
36 * stores to system memory with respect to writes to the device.
37 * However, smp_wmb() can be a lighter-weight eieio barrier on
38 * SMP since it is only used to order updates to system memory.
39 */
40#define mb() __asm__ __volatile__ ("sync" : : : "memory")
41#define rmb() __asm__ __volatile__ ("lwsync" : : : "memory")
42#define wmb() __asm__ __volatile__ ("sync" : : : "memory")
43#define read_barrier_depends() do { } while(0)
44
45#define set_mb(var, value) do { var = value; smp_mb(); } while (0)
46#define set_wmb(var, value) do { var = value; smp_wmb(); } while (0)
47
48#ifdef CONFIG_SMP
49#define smp_mb() mb()
50#define smp_rmb() rmb()
51#define smp_wmb() __asm__ __volatile__ ("eieio" : : : "memory")
52#define smp_read_barrier_depends() read_barrier_depends()
53#else
54#define smp_mb() __asm__ __volatile__("": : :"memory")
55#define smp_rmb() __asm__ __volatile__("": : :"memory")
56#define smp_wmb() __asm__ __volatile__("": : :"memory")
57#define smp_read_barrier_depends() do { } while(0)
58#endif /* CONFIG_SMP */
59
60#ifdef __KERNEL__
61struct task_struct;
62struct pt_regs;
63
64#ifdef CONFIG_DEBUGGER
65
66extern int (*__debugger)(struct pt_regs *regs);
67extern int (*__debugger_ipi)(struct pt_regs *regs);
68extern int (*__debugger_bpt)(struct pt_regs *regs);
69extern int (*__debugger_sstep)(struct pt_regs *regs);
70extern int (*__debugger_iabr_match)(struct pt_regs *regs);
71extern int (*__debugger_dabr_match)(struct pt_regs *regs);
72extern int (*__debugger_fault_handler)(struct pt_regs *regs);
73
74#define DEBUGGER_BOILERPLATE(__NAME) \
75static inline int __NAME(struct pt_regs *regs) \
76{ \
77 if (unlikely(__ ## __NAME)) \
78 return __ ## __NAME(regs); \
79 return 0; \
80}
81
82DEBUGGER_BOILERPLATE(debugger)
83DEBUGGER_BOILERPLATE(debugger_ipi)
84DEBUGGER_BOILERPLATE(debugger_bpt)
85DEBUGGER_BOILERPLATE(debugger_sstep)
86DEBUGGER_BOILERPLATE(debugger_iabr_match)
87DEBUGGER_BOILERPLATE(debugger_dabr_match)
88DEBUGGER_BOILERPLATE(debugger_fault_handler)
89
90#ifdef CONFIG_XMON
91extern void xmon_init(void);
92#endif
93
94#else
95static inline int debugger(struct pt_regs *regs) { return 0; }
96static inline int debugger_ipi(struct pt_regs *regs) { return 0; }
97static inline int debugger_bpt(struct pt_regs *regs) { return 0; }
98static inline int debugger_sstep(struct pt_regs *regs) { return 0; }
99static inline int debugger_iabr_match(struct pt_regs *regs) { return 0; }
100static inline int debugger_dabr_match(struct pt_regs *regs) { return 0; }
101static inline int debugger_fault_handler(struct pt_regs *regs) { return 0; }
102#endif
103
104extern int fix_alignment(struct pt_regs *regs);
105extern void bad_page_fault(struct pt_regs *regs, unsigned long address,
106 int sig);
107extern void show_regs(struct pt_regs * regs);
108extern void low_hash_fault(struct pt_regs *regs, unsigned long address);
109extern int die(const char *str, struct pt_regs *regs, long err);
110
111extern int _get_PVR(void);
112extern void giveup_fpu(struct task_struct *);
113extern void disable_kernel_fp(void);
114extern void flush_fp_to_thread(struct task_struct *);
115extern void enable_kernel_fp(void);
116extern void giveup_altivec(struct task_struct *);
117extern void disable_kernel_altivec(void);
118extern void enable_kernel_altivec(void);
119extern int emulate_altivec(struct pt_regs *);
120extern void cvt_fd(float *from, double *to, unsigned long *fpscr);
121extern void cvt_df(double *from, float *to, unsigned long *fpscr);
122
123#ifdef CONFIG_ALTIVEC
124extern void flush_altivec_to_thread(struct task_struct *);
125#else
126static inline void flush_altivec_to_thread(struct task_struct *t)
127{
128}
129#endif
130
131extern int mem_init_done; /* set on boot once kmalloc can be called */
132
133/* EBCDIC -> ASCII conversion for [0-9A-Z] on iSeries */
134extern unsigned char e2a(unsigned char);
135
136extern struct task_struct *__switch_to(struct task_struct *,
137 struct task_struct *);
138#define switch_to(prev, next, last) ((last) = __switch_to((prev), (next)))
139
140struct thread_struct;
141extern struct task_struct * _switch(struct thread_struct *prev,
142 struct thread_struct *next);
143
144static inline int __is_processor(unsigned long pv)
145{
146 unsigned long pvr;
147 asm("mfspr %0, 0x11F" : "=r" (pvr));
148 return(PVR_VER(pvr) == pv);
149}
150
151/*
152 * Atomic exchange
153 *
154 * Changes the memory location '*ptr' to be val and returns
155 * the previous value stored there.
156 *
157 * Inline asm pulled from arch/ppc/kernel/misc.S so ppc64
158 * is more like most of the other architectures.
159 */
160static __inline__ unsigned long
161__xchg_u32(volatile int *m, unsigned long val)
162{
163 unsigned long dummy;
164
165 __asm__ __volatile__(
166 EIEIO_ON_SMP
167"1: lwarx %0,0,%3 # __xchg_u32\n\
168 stwcx. %2,0,%3\n\
1692: bne- 1b"
170 ISYNC_ON_SMP
171 : "=&r" (dummy), "=m" (*m)
172 : "r" (val), "r" (m)
173 : "cc", "memory");
174
175 return (dummy);
176}
177
178static __inline__ unsigned long
179__xchg_u64(volatile long *m, unsigned long val)
180{
181 unsigned long dummy;
182
183 __asm__ __volatile__(
184 EIEIO_ON_SMP
185"1: ldarx %0,0,%3 # __xchg_u64\n\
186 stdcx. %2,0,%3\n\
1872: bne- 1b"
188 ISYNC_ON_SMP
189 : "=&r" (dummy), "=m" (*m)
190 : "r" (val), "r" (m)
191 : "cc", "memory");
192
193 return (dummy);
194}
195
196/*
197 * This function doesn't exist, so you'll get a linker error
198 * if something tries to do an invalid xchg().
199 */
200extern void __xchg_called_with_bad_pointer(void);
201
202static __inline__ unsigned long
203__xchg(volatile void *ptr, unsigned long x, int size)
204{
205 switch (size) {
206 case 4:
207 return __xchg_u32(ptr, x);
208 case 8:
209 return __xchg_u64(ptr, x);
210 }
211 __xchg_called_with_bad_pointer();
212 return x;
213}
214
215#define xchg(ptr,x) \
216 ({ \
217 __typeof__(*(ptr)) _x_ = (x); \
218 (__typeof__(*(ptr))) __xchg((ptr), (unsigned long)_x_, sizeof(*(ptr))); \
219 })
220
221#define tas(ptr) (xchg((ptr),1))
222
223#define __HAVE_ARCH_CMPXCHG 1
224
225static __inline__ unsigned long
226__cmpxchg_u32(volatile int *p, int old, int new)
227{
228 unsigned int prev;
229
230 __asm__ __volatile__ (
231 EIEIO_ON_SMP
232"1: lwarx %0,0,%2 # __cmpxchg_u32\n\
233 cmpw 0,%0,%3\n\
234 bne- 2f\n\
235 stwcx. %4,0,%2\n\
236 bne- 1b"
237 ISYNC_ON_SMP
238 "\n\
2392:"
240 : "=&r" (prev), "=m" (*p)
241 : "r" (p), "r" (old), "r" (new), "m" (*p)
242 : "cc", "memory");
243
244 return prev;
245}
246
247static __inline__ unsigned long
248__cmpxchg_u64(volatile long *p, unsigned long old, unsigned long new)
249{
250 unsigned long prev;
251
252 __asm__ __volatile__ (
253 EIEIO_ON_SMP
254"1: ldarx %0,0,%2 # __cmpxchg_u64\n\
255 cmpd 0,%0,%3\n\
256 bne- 2f\n\
257 stdcx. %4,0,%2\n\
258 bne- 1b"
259 ISYNC_ON_SMP
260 "\n\
2612:"
262 : "=&r" (prev), "=m" (*p)
263 : "r" (p), "r" (old), "r" (new), "m" (*p)
264 : "cc", "memory");
265
266 return prev;
267}
268
269/* This function doesn't exist, so you'll get a linker error
270 if something tries to do an invalid cmpxchg(). */
271extern void __cmpxchg_called_with_bad_pointer(void);
272
273static __inline__ unsigned long
274__cmpxchg(volatile void *ptr, unsigned long old, unsigned long new, int size)
275{
276 switch (size) {
277 case 4:
278 return __cmpxchg_u32(ptr, old, new);
279 case 8:
280 return __cmpxchg_u64(ptr, old, new);
281 }
282 __cmpxchg_called_with_bad_pointer();
283 return old;
284}
285
286#define cmpxchg(ptr,o,n) \
287 ({ \
288 __typeof__(*(ptr)) _o_ = (o); \
289 __typeof__(*(ptr)) _n_ = (n); \
290 (__typeof__(*(ptr))) __cmpxchg((ptr), (unsigned long)_o_, \
291 (unsigned long)_n_, sizeof(*(ptr))); \
292 })
293
294/*
295 * We handle most unaligned accesses in hardware. On the other hand
296 * unaligned DMA can be very expensive on some ppc64 IO chips (it does
297 * powers of 2 writes until it reaches sufficient alignment).
298 *
299 * Based on this we disable the IP header alignment in network drivers.
300 */
301#define NET_IP_ALIGN 0
302
303#define arch_align_stack(x) (x)
304
305#endif /* __KERNEL__ */
306#endif