Merge master.kernel.org:/pub/scm/linux/kernel/git/paulus/powerpc-merge
[linux-2.6] / include / asm-sparc / system.h
1 /* $Id: system.h,v 1.86 2001/10/30 04:57:10 davem Exp $ */
2 #include <linux/config.h>
3
4 #ifndef __SPARC_SYSTEM_H
5 #define __SPARC_SYSTEM_H
6
7 #include <linux/config.h>
8 #include <linux/kernel.h>
9 #include <linux/threads.h>      /* NR_CPUS */
10 #include <linux/thread_info.h>
11
12 #include <asm/page.h>
13 #include <asm/psr.h>
14 #include <asm/ptrace.h>
15 #include <asm/btfixup.h>
16
17 #ifndef __ASSEMBLY__
18
19 /*
20  * Sparc (general) CPU types
21  */
22 enum sparc_cpu {
23   sun4        = 0x00,
24   sun4c       = 0x01,
25   sun4m       = 0x02,
26   sun4d       = 0x03,
27   sun4e       = 0x04,
28   sun4u       = 0x05, /* V8 ploos ploos */
29   sun_unknown = 0x06,
30   ap1000      = 0x07, /* almost a sun4m */
31 };
32
33 /* Really, userland should not be looking at any of this... */
34 #ifdef __KERNEL__
35
36 extern enum sparc_cpu sparc_cpu_model;
37
38 #ifndef CONFIG_SUN4
39 #define ARCH_SUN4C_SUN4 (sparc_cpu_model==sun4c)
40 #define ARCH_SUN4 0
41 #else
42 #define ARCH_SUN4C_SUN4 1
43 #define ARCH_SUN4 1
44 #endif
45
46 #define SUN4M_NCPUS            4              /* Architectural limit of sun4m. */
47
48 extern struct thread_info *current_set[NR_CPUS];
49
50 extern unsigned long empty_bad_page;
51 extern unsigned long empty_bad_page_table;
52 extern unsigned long empty_zero_page;
53
54 extern void sun_do_break(void);
55 extern int serial_console;
56 extern int stop_a_enabled;
57
58 static __inline__ int con_is_present(void)
59 {
60         return serial_console ? 0 : 1;
61 }
62
63 /* When a context switch happens we must flush all user windows so that
64  * the windows of the current process are flushed onto its stack. This
65  * way the windows are all clean for the next process and the stack
66  * frames are up to date.
67  */
68 extern void flush_user_windows(void);
69 extern void kill_user_windows(void);
70 extern void synchronize_user_stack(void);
71 extern void fpsave(unsigned long *fpregs, unsigned long *fsr,
72                    void *fpqueue, unsigned long *fpqdepth);
73
74 #ifdef CONFIG_SMP
75 #define SWITCH_ENTER(prv) \
76         do {                    \
77         if (test_tsk_thread_flag(prv, TIF_USEDFPU)) { \
78                 put_psr(get_psr() | PSR_EF); \
79                 fpsave(&(prv)->thread.float_regs[0], &(prv)->thread.fsr, \
80                        &(prv)->thread.fpqueue[0], &(prv)->thread.fpqdepth); \
81                 clear_tsk_thread_flag(prv, TIF_USEDFPU); \
82                 (prv)->thread.kregs->psr &= ~PSR_EF; \
83         } \
84         } while(0)
85
86 #define SWITCH_DO_LAZY_FPU(next)        /* */
87 #else
88 #define SWITCH_ENTER(prv)               /* */
89 #define SWITCH_DO_LAZY_FPU(nxt) \
90         do {                    \
91         if (last_task_used_math != (nxt))               \
92                 (nxt)->thread.kregs->psr&=~PSR_EF;      \
93         } while(0)
94 #endif
95
96 /*
97  * Flush windows so that the VM switch which follows
98  * would not pull the stack from under us.
99  *
100  * SWITCH_ENTER and SWITH_DO_LAZY_FPU do not work yet (e.g. SMP does not work)
101  * XXX WTF is the above comment? Found in late teen 2.4.x.
102  */
103 #define prepare_arch_switch(next) do { \
104         __asm__ __volatile__( \
105         ".globl\tflush_patch_switch\nflush_patch_switch:\n\t" \
106         "save %sp, -0x40, %sp; save %sp, -0x40, %sp; save %sp, -0x40, %sp\n\t" \
107         "save %sp, -0x40, %sp; save %sp, -0x40, %sp; save %sp, -0x40, %sp\n\t" \
108         "save %sp, -0x40, %sp\n\t" \
109         "restore; restore; restore; restore; restore; restore; restore"); \
110 } while(0)
111
112         /* Much care has gone into this code, do not touch it.
113          *
114          * We need to loadup regs l0/l1 for the newly forked child
115          * case because the trap return path relies on those registers
116          * holding certain values, gcc is told that they are clobbered.
117          * Gcc needs registers for 3 values in and 1 value out, so we
118          * clobber every non-fixed-usage register besides l2/l3/o4/o5.  -DaveM
119          *
120          * Hey Dave, that do not touch sign is too much of an incentive
121          * - Anton & Pete
122          */
123 #define switch_to(prev, next, last) do {                                                \
124         SWITCH_ENTER(prev);                                                             \
125         SWITCH_DO_LAZY_FPU(next);                                                       \
126         cpu_set(smp_processor_id(), next->active_mm->cpu_vm_mask);                      \
127         __asm__ __volatile__(                                                           \
128         "sethi  %%hi(here - 0x8), %%o7\n\t"                                             \
129         "mov    %%g6, %%g3\n\t"                                                         \
130         "or     %%o7, %%lo(here - 0x8), %%o7\n\t"                                       \
131         "rd     %%psr, %%g4\n\t"                                                        \
132         "std    %%sp, [%%g6 + %4]\n\t"                                                  \
133         "rd     %%wim, %%g5\n\t"                                                        \
134         "wr     %%g4, 0x20, %%psr\n\t"                                                  \
135         "nop\n\t"                                                                       \
136         "std    %%g4, [%%g6 + %3]\n\t"                                                  \
137         "ldd    [%2 + %3], %%g4\n\t"                                                    \
138         "mov    %2, %%g6\n\t"                                                           \
139         ".globl patchme_store_new_current\n"                                            \
140 "patchme_store_new_current:\n\t"                                                        \
141         "st     %2, [%1]\n\t"                                                           \
142         "wr     %%g4, 0x20, %%psr\n\t"                                                  \
143         "nop\n\t"                                                                       \
144         "nop\n\t"                                                                       \
145         "nop\n\t"       /* LEON needs all 3 nops: load to %sp depends on CWP. */                \
146         "ldd    [%%g6 + %4], %%sp\n\t"                                                  \
147         "wr     %%g5, 0x0, %%wim\n\t"                                                   \
148         "ldd    [%%sp + 0x00], %%l0\n\t"                                                \
149         "ldd    [%%sp + 0x38], %%i6\n\t"                                                \
150         "wr     %%g4, 0x0, %%psr\n\t"                                                   \
151         "nop\n\t"                                                                       \
152         "nop\n\t"                                                                       \
153         "jmpl   %%o7 + 0x8, %%g0\n\t"                                                   \
154         " ld    [%%g3 + %5], %0\n\t"                                                    \
155         "here:\n"                                                                       \
156         : "=&r" (last)                                                                  \
157         : "r" (&(current_set[hard_smp_processor_id()])),        \
158           "r" ((next)->thread_info),                            \
159           "i" (TI_KPSR),                                        \
160           "i" (TI_KSP),                                         \
161           "i" (TI_TASK)                                         \
162         :       "g1", "g2", "g3", "g4", "g5",       "g7",       \
163           "l0", "l1",       "l3", "l4", "l5", "l6", "l7",       \
164           "i0", "i1", "i2", "i3", "i4", "i5",                   \
165           "o0", "o1", "o2", "o3",                   "o7");      \
166         } while(0)
167
168 /*
169  * Changing the IRQ level on the Sparc.
170  */
171 extern void local_irq_restore(unsigned long);
172 extern unsigned long __local_irq_save(void);
173 extern void local_irq_enable(void);
174
175 static inline unsigned long getipl(void)
176 {
177         unsigned long retval;
178
179         __asm__ __volatile__("rd        %%psr, %0" : "=r" (retval));
180         return retval;
181 }
182
183 #define local_save_flags(flags) ((flags) = getipl())
184 #define local_irq_save(flags)   ((flags) = __local_irq_save())
185 #define local_irq_disable()     ((void) __local_irq_save())
186 #define irqs_disabled()         ((getipl() & PSR_PIL) != 0)
187
188 /* XXX Change this if we ever use a PSO mode kernel. */
189 #define mb()    __asm__ __volatile__ ("" : : : "memory")
190 #define rmb()   mb()
191 #define wmb()   mb()
192 #define read_barrier_depends()  do { } while(0)
193 #define set_mb(__var, __value)  do { __var = __value; mb(); } while(0)
194 #define set_wmb(__var, __value) set_mb(__var, __value)
195 #define smp_mb()        __asm__ __volatile__("":::"memory")
196 #define smp_rmb()       __asm__ __volatile__("":::"memory")
197 #define smp_wmb()       __asm__ __volatile__("":::"memory")
198 #define smp_read_barrier_depends()      do { } while(0)
199
200 #define nop() __asm__ __volatile__ ("nop")
201
202 /* This has special calling conventions */
203 #ifndef CONFIG_SMP
204 BTFIXUPDEF_CALL(void, ___xchg32, void)
205 #endif
206
207 static inline unsigned long xchg_u32(__volatile__ unsigned long *m, unsigned long val)
208 {
209 #ifdef CONFIG_SMP
210         __asm__ __volatile__("swap [%2], %0"
211                              : "=&r" (val)
212                              : "0" (val), "r" (m)
213                              : "memory");
214         return val;
215 #else
216         register unsigned long *ptr asm("g1");
217         register unsigned long ret asm("g2");
218
219         ptr = (unsigned long *) m;
220         ret = val;
221
222         /* Note: this is magic and the nop there is
223            really needed. */
224         __asm__ __volatile__(
225         "mov    %%o7, %%g4\n\t"
226         "call   ___f____xchg32\n\t"
227         " nop\n\t"
228         : "=&r" (ret)
229         : "0" (ret), "r" (ptr)
230         : "g3", "g4", "g7", "memory", "cc");
231
232         return ret;
233 #endif
234 }
235
236 #define xchg(ptr,x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))
237 #define tas(ptr) (xchg((ptr),1))
238
239 extern void __xchg_called_with_bad_pointer(void);
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         };
247         __xchg_called_with_bad_pointer();
248         return x;
249 }
250
251 extern void die_if_kernel(char *str, struct pt_regs *regs) __attribute__ ((noreturn));
252
253 #endif /* __KERNEL__ */
254
255 #endif /* __ASSEMBLY__ */
256
257 #define arch_align_stack(x) (x)
258
259 #endif /* !(__SPARC_SYSTEM_H) */