blob: 73348c3f858b673b73513e97d913cb4e265e38c6 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001#ifndef _ASM_M32R_SYSTEM_H
2#define _ASM_M32R_SYSTEM_H
3
4/*
5 * This file is subject to the terms and conditions of the GNU General Public
6 * License. See the file "COPYING" in the main directory of this archive
7 * for more details.
8 *
9 * Copyright (C) 2001 by Hiroyuki Kondo, Hirokazu Takata, and Hitoshi Yamamoto
10 * Copyright (C) 2004 Hirokazu Takata <takata at linux-m32r.org>
11 */
12
13#include <linux/config.h>
14
15#ifdef __KERNEL__
16
17/*
18 * switch_to(prev, next) should switch from task `prev' to `next'
19 * `prev' will never be the same as `next'.
20 *
21 * `next' and `prev' should be struct task_struct, but it isn't always defined
22 */
23
24#ifndef CONFIG_SMP
25#define prepare_to_switch() do { } while(0)
26#endif /* not CONFIG_SMP */
27
28#define switch_to(prev, next, last) do { \
29 register unsigned long arg0 __asm__ ("r0") = (unsigned long)prev; \
30 register unsigned long arg1 __asm__ ("r1") = (unsigned long)next; \
31 register unsigned long *oldsp __asm__ ("r2") = &(prev->thread.sp); \
32 register unsigned long *newsp __asm__ ("r3") = &(next->thread.sp); \
33 register unsigned long *oldlr __asm__ ("r4") = &(prev->thread.lr); \
34 register unsigned long *newlr __asm__ ("r5") = &(next->thread.lr); \
35 register struct task_struct *__last __asm__ ("r6"); \
36 __asm__ __volatile__ ( \
37 "st r8, @-r15 \n\t" \
38 "st r9, @-r15 \n\t" \
39 "st r10, @-r15 \n\t" \
40 "st r11, @-r15 \n\t" \
41 "st r12, @-r15 \n\t" \
42 "st r13, @-r15 \n\t" \
43 "st r14, @-r15 \n\t" \
44 "seth r14, #high(1f) \n\t" \
45 "or3 r14, r14, #low(1f) \n\t" \
46 "st r14, @r4 ; store old LR \n\t" \
47 "st r15, @r2 ; store old SP \n\t" \
48 "ld r15, @r3 ; load new SP \n\t" \
49 "st r0, @-r15 ; store 'prev' onto new stack \n\t" \
50 "ld r14, @r5 ; load new LR \n\t" \
51 "jmp r14 \n\t" \
52 ".fillinsn \n " \
53 "1: \n\t" \
54 "ld r6, @r15+ ; load 'prev' from new stack \n\t" \
55 "ld r14, @r15+ \n\t" \
56 "ld r13, @r15+ \n\t" \
57 "ld r12, @r15+ \n\t" \
58 "ld r11, @r15+ \n\t" \
59 "ld r10, @r15+ \n\t" \
60 "ld r9, @r15+ \n\t" \
61 "ld r8, @r15+ \n\t" \
62 : "=&r" (__last) \
63 : "r" (arg0), "r" (arg1), "r" (oldsp), "r" (newsp), \
64 "r" (oldlr), "r" (newlr) \
65 : "memory" \
66 ); \
67 last = __last; \
68} while(0)
69
70/* Interrupt Control */
71#if !defined(CONFIG_CHIP_M32102)
72#define local_irq_enable() \
73 __asm__ __volatile__ ("setpsw #0x40 -> nop": : :"memory")
74#define local_irq_disable() \
75 __asm__ __volatile__ ("clrpsw #0x40 -> nop": : :"memory")
76#else /* CONFIG_CHIP_M32102 */
77static inline void local_irq_enable(void)
78{
79 unsigned long tmpreg;
80 __asm__ __volatile__(
81 "mvfc %0, psw; \n\t"
82 "or3 %0, %0, #0x0040; \n\t"
83 "mvtc %0, psw; \n\t"
84 : "=&r" (tmpreg) : : "cbit", "memory");
85}
86
87static inline void local_irq_disable(void)
88{
89 unsigned long tmpreg0, tmpreg1;
90 __asm__ __volatile__(
91 "ld24 %0, #0 ; Use 32-bit insn. \n\t"
92 "mvfc %1, psw ; No interrupt can be accepted here. \n\t"
93 "mvtc %0, psw \n\t"
94 "and3 %0, %1, #0xffbf \n\t"
95 "mvtc %0, psw \n\t"
96 : "=&r" (tmpreg0), "=&r" (tmpreg1) : : "cbit", "memory");
97}
98#endif /* CONFIG_CHIP_M32102 */
99
100#define local_save_flags(x) \
101 __asm__ __volatile__("mvfc %0,psw" : "=r"(x) : /* no input */)
102
103#define local_irq_restore(x) \
104 __asm__ __volatile__("mvtc %0,psw" : /* no outputs */ \
105 : "r" (x) : "cbit", "memory")
106
107#if !defined(CONFIG_CHIP_M32102)
108#define local_irq_save(x) \
109 __asm__ __volatile__( \
110 "mvfc %0, psw; \n\t" \
111 "clrpsw #0x40 -> nop; \n\t" \
112 : "=r" (x) : /* no input */ : "memory")
113#else /* CONFIG_CHIP_M32102 */
114#define local_irq_save(x) \
115 ({ \
116 unsigned long tmpreg; \
117 __asm__ __volatile__( \
118 "ld24 %1, #0 \n\t" \
119 "mvfc %0, psw \n\t" \
120 "mvtc %1, psw \n\t" \
121 "and3 %1, %0, #0xffbf \n\t" \
122 "mvtc %1, psw \n\t" \
123 : "=r" (x), "=&r" (tmpreg) \
124 : : "cbit", "memory"); \
125 })
126#endif /* CONFIG_CHIP_M32102 */
127
128#define irqs_disabled() \
129 ({ \
130 unsigned long flags; \
131 local_save_flags(flags); \
132 !(flags & 0x40); \
133 })
134
135#endif /* __KERNEL__ */
136
137#define nop() __asm__ __volatile__ ("nop" : : )
138
139#define xchg(ptr,x) \
140 ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))
141
142#define tas(ptr) (xchg((ptr),1))
143
144#ifdef CONFIG_SMP
145extern void __xchg_called_with_bad_pointer(void);
146#endif
147
148#ifdef CONFIG_CHIP_M32700_TS1
149#define DCACHE_CLEAR(reg0, reg1, addr) \
150 "seth "reg1", #high(dcache_dummy); \n\t" \
151 "or3 "reg1", "reg1", #low(dcache_dummy); \n\t" \
152 "lock "reg0", @"reg1"; \n\t" \
153 "add3 "reg0", "addr", #0x1000; \n\t" \
154 "ld "reg0", @"reg0"; \n\t" \
155 "add3 "reg0", "addr", #0x2000; \n\t" \
156 "ld "reg0", @"reg0"; \n\t" \
157 "unlock "reg0", @"reg1"; \n\t"
158 /* FIXME: This workaround code cannot handle kenrel modules
159 * correctly under SMP environment.
160 */
161#else /* CONFIG_CHIP_M32700_TS1 */
162#define DCACHE_CLEAR(reg0, reg1, addr)
163#endif /* CONFIG_CHIP_M32700_TS1 */
164
165static __inline__ unsigned long __xchg(unsigned long x, volatile void * ptr,
166 int size)
167{
168 unsigned long flags;
169 unsigned long tmp = 0;
170
171 local_irq_save(flags);
172
173 switch (size) {
174#ifndef CONFIG_SMP
175 case 1:
176 __asm__ __volatile__ (
177 "ldb %0, @%2 \n\t"
178 "stb %1, @%2 \n\t"
179 : "=&r" (tmp) : "r" (x), "r" (ptr) : "memory");
180 break;
181 case 2:
182 __asm__ __volatile__ (
183 "ldh %0, @%2 \n\t"
184 "sth %1, @%2 \n\t"
185 : "=&r" (tmp) : "r" (x), "r" (ptr) : "memory");
186 break;
187 case 4:
188 __asm__ __volatile__ (
189 "ld %0, @%2 \n\t"
190 "st %1, @%2 \n\t"
191 : "=&r" (tmp) : "r" (x), "r" (ptr) : "memory");
192 break;
193#else /* CONFIG_SMP */
194 case 4:
195 __asm__ __volatile__ (
196 DCACHE_CLEAR("%0", "r4", "%2")
197 "lock %0, @%2; \n\t"
198 "unlock %1, @%2; \n\t"
199 : "=&r" (tmp) : "r" (x), "r" (ptr)
200 : "memory"
201#ifdef CONFIG_CHIP_M32700_TS1
202 , "r4"
203#endif /* CONFIG_CHIP_M32700_TS1 */
204 );
205 break;
206 default:
207 __xchg_called_with_bad_pointer();
208#endif /* CONFIG_SMP */
209 }
210
211 local_irq_restore(flags);
212
213 return (tmp);
214}
215
216/*
217 * Memory barrier.
218 *
219 * mb() prevents loads and stores being reordered across this point.
220 * rmb() prevents loads being reordered across this point.
221 * wmb() prevents stores being reordered across this point.
222 */
223#define mb() barrier()
224#define rmb() mb()
225#define wmb() mb()
226
227/**
228 * read_barrier_depends - Flush all pending reads that subsequents reads
229 * depend on.
230 *
231 * No data-dependent reads from memory-like regions are ever reordered
232 * over this barrier. All reads preceding this primitive are guaranteed
233 * to access memory (but not necessarily other CPUs' caches) before any
234 * reads following this primitive that depend on the data return by
235 * any of the preceding reads. This primitive is much lighter weight than
236 * rmb() on most CPUs, and is never heavier weight than is
237 * rmb().
238 *
239 * These ordering constraints are respected by both the local CPU
240 * and the compiler.
241 *
242 * Ordering is not guaranteed by anything other than these primitives,
243 * not even by data dependencies. See the documentation for
244 * memory_barrier() for examples and URLs to more information.
245 *
246 * For example, the following code would force ordering (the initial
247 * value of "a" is zero, "b" is one, and "p" is "&a"):
248 *
249 * <programlisting>
250 * CPU 0 CPU 1
251 *
252 * b = 2;
253 * memory_barrier();
254 * p = &b; q = p;
255 * read_barrier_depends();
256 * d = *q;
257 * </programlisting>
258 *
259 *
260 * because the read of "*q" depends on the read of "p" and these
261 * two reads are separated by a read_barrier_depends(). However,
262 * the following code, with the same initial values for "a" and "b":
263 *
264 * <programlisting>
265 * CPU 0 CPU 1
266 *
267 * a = 2;
268 * memory_barrier();
269 * b = 3; y = b;
270 * read_barrier_depends();
271 * x = a;
272 * </programlisting>
273 *
274 * does not enforce ordering, since there is no data dependency between
275 * the read of "a" and the read of "b". Therefore, on some CPUs, such
276 * as Alpha, "y" could be set to 3 and "x" to 0. Use rmb()
277 * in cases like thiswhere there are no data dependencies.
278 **/
279
280#define read_barrier_depends() do { } while (0)
281
282#ifdef CONFIG_SMP
283#define smp_mb() mb()
284#define smp_rmb() rmb()
285#define smp_wmb() wmb()
286#define smp_read_barrier_depends() read_barrier_depends()
287#else
288#define smp_mb() barrier()
289#define smp_rmb() barrier()
290#define smp_wmb() barrier()
291#define smp_read_barrier_depends() do { } while (0)
292#endif
293
294#define set_mb(var, value) do { xchg(&var, value); } while (0)
295#define set_wmb(var, value) do { var = value; wmb(); } while (0)
296
297#define arch_align_stack(x) (x)
298
299#endif /* _ASM_M32R_SYSTEM_H */