File: /usr/src/linux/include/asm-sparc/system.h

1     /* $Id: system.h,v 1.84 2000/09/23 02:11:22 davem Exp $ */
2     #include <linux/config.h>
3     
4     #ifndef __SPARC_SYSTEM_H
5     #define __SPARC_SYSTEM_H
6     
7     #include <linux/kernel.h>
8     
9     #include <asm/segment.h>
10     
11     #ifdef __KERNEL__
12     #include <asm/page.h>
13     #include <asm/oplib.h>
14     #include <asm/psr.h>
15     #include <asm/ptrace.h>
16     #include <asm/btfixup.h>
17     
18     #endif /* __KERNEL__ */
19     
20     #ifndef __ASSEMBLY__
21     
22     /*
23      * Sparc (general) CPU types
24      */
25     enum sparc_cpu {
26       sun4        = 0x00,
27       sun4c       = 0x01,
28       sun4m       = 0x02,
29       sun4d       = 0x03,
30       sun4e       = 0x04,
31       sun4u       = 0x05, /* V8 ploos ploos */
32       sun_unknown = 0x06,
33       ap1000      = 0x07, /* almost a sun4m */
34     };
35     
36     /* Really, userland should not be looking at any of this... */
37     #ifdef __KERNEL__
38     
39     extern enum sparc_cpu sparc_cpu_model;
40     
41     #ifndef CONFIG_SUN4
42     #define ARCH_SUN4C_SUN4 (sparc_cpu_model==sun4c)
43     #define ARCH_SUN4 0
44     #else
45     #define ARCH_SUN4C_SUN4 1
46     #define ARCH_SUN4 1
47     #endif
48     
49     #define SUN4M_NCPUS            4              /* Architectural limit of sun4m. */
50     
51     extern unsigned long empty_bad_page;
52     extern unsigned long empty_bad_page_table;
53     extern unsigned long empty_zero_page;
54     
55     extern struct linux_romvec *romvec;
56     #define halt() romvec->pv_halt()
57     
58     /* When a context switch happens we must flush all user windows so that
59      * the windows of the current process are flushed onto its stack. This
60      * way the windows are all clean for the next process and the stack
61      * frames are up to date.
62      */
63     extern void flush_user_windows(void);
64     extern void kill_user_windows(void);
65     extern void synchronize_user_stack(void);
66     extern void fpsave(unsigned long *fpregs, unsigned long *fsr,
67     		   void *fpqueue, unsigned long *fpqdepth);
68     
69     #ifdef CONFIG_SMP
70     #define SWITCH_ENTER \
71     	if(prev->flags & PF_USEDFPU) { \
72     		put_psr(get_psr() | PSR_EF); \
73     		fpsave(&prev->thread.float_regs[0], &prev->thread.fsr, \
74     		       &prev->thread.fpqueue[0], &prev->thread.fpqdepth); \
75     		prev->flags &= ~PF_USEDFPU; \
76     		prev->thread.kregs->psr &= ~PSR_EF; \
77     	}
78     
79     #define SWITCH_DO_LAZY_FPU
80     #else
81     #define SWITCH_ENTER
82     #define SWITCH_DO_LAZY_FPU if(last_task_used_math != next) next->thread.kregs->psr&=~PSR_EF;
83     #endif
84     
85     /*
86      * Flush windows so that the VM switch which follows
87      * would not pull the stack from under us.
88      *
89      * SWITCH_ENTER and SWITH_DO_LAZY_FPU do not work yet (e.g. SMP does not work)
90      */
91     #define prepare_to_switch() do { \
92     	__asm__ __volatile__( \
93     	".globl\tflush_patch_switch\nflush_patch_switch:\n\t" \
94     	"save %sp, -0x40, %sp; save %sp, -0x40, %sp; save %sp, -0x40, %sp\n\t" \
95     	"save %sp, -0x40, %sp; save %sp, -0x40, %sp; save %sp, -0x40, %sp\n\t" \
96     	"save %sp, -0x40, %sp\n\t" \
97     	"restore; restore; restore; restore; restore; restore; restore"); \
98     } while(0)
99     
100     	/* Much care has gone into this code, do not touch it.
101     	 *
102     	 * We need to loadup regs l0/l1 for the newly forked child
103     	 * case because the trap return path relies on those registers
104     	 * holding certain values, gcc is told that they are clobbered.
105     	 * Gcc needs registers for 3 values in and 1 value out, so we
106     	 * clobber every non-fixed-usage register besides l2/l3/o4/o5.  -DaveM
107     	 *
108     	 * Hey Dave, that do not touch sign is too much of an incentive
109     	 * - Anton
110     	 */
111     #define switch_to(prev, next, last) do {						\
112     	__label__ here;									\
113     	register unsigned long task_pc asm("o7");					\
114     	extern struct task_struct *current_set[NR_CPUS];				\
115     	SWITCH_ENTER									\
116     	SWITCH_DO_LAZY_FPU								\
117     	next->active_mm->cpu_vm_mask |= (1 << smp_processor_id());			\
118     	task_pc = ((unsigned long) &&here) - 0x8;					\
119     	__asm__ __volatile__(								\
120     	"mov	%%g6, %%g3\n\t"								\
121     	"rd	%%psr, %%g4\n\t"							\
122     	"std	%%sp, [%%g6 + %4]\n\t"							\
123     	"rd	%%wim, %%g5\n\t"							\
124     	"wr	%%g4, 0x20, %%psr\n\t"							\
125     	"nop\n\t"									\
126     	"std	%%g4, [%%g6 + %3]\n\t"							\
127     	"ldd	[%2 + %3], %%g4\n\t"							\
128     	"mov	%2, %%g6\n\t"								\
129     	".globl	patchme_store_new_current\n"						\
130     "patchme_store_new_current:\n\t"							\
131     	"st	%2, [%1]\n\t"								\
132     	"wr	%%g4, 0x20, %%psr\n\t"							\
133     	"nop\n\t"									\
134     	"nop\n\t"									\
135     	"ldd	[%%g6 + %4], %%sp\n\t"							\
136     	"wr	%%g5, 0x0, %%wim\n\t"							\
137     	"ldd	[%%sp + 0x00], %%l0\n\t"						\
138     	"ldd	[%%sp + 0x38], %%i6\n\t"						\
139     	"wr	%%g4, 0x0, %%psr\n\t"							\
140     	"nop\n\t"									\
141     	"nop\n\t"									\
142     	"jmpl	%%o7 + 0x8, %%g0\n\t"							\
143     	" mov	%%g3, %0\n\t"								\
144             : "=&r" (last)									\
145             : "r" (&(current_set[hard_smp_processor_id()])), "r" (next),			\
146     	  "i" ((const unsigned long)(&((struct task_struct *)0)->thread.kpsr)),		\
147     	  "i" ((const unsigned long)(&((struct task_struct *)0)->thread.ksp)),		\
148     	  "r" (task_pc)									\
149     	: "g1", "g2", "g3", "g4", "g5", "g7", "l0", "l1",				\
150     	"l4", "l5", "l6", "l7", "i0", "i1", "i2", "i3", "i4", "i5", "o0", "o1", "o2",	\
151     	"o3");										\
152     here:  } while(0)
153     
154     /*
155      * Changing the IRQ level on the Sparc.
156      */
157     extern __inline__ void setipl(unsigned long __orig_psr)
158     {
159     	__asm__ __volatile__("
160     		wr	%0, 0x0, %%psr
161     		nop; nop; nop
162     "		: /* no outputs */
163     		: "r" (__orig_psr)
164     		: "memory", "cc");
165     }
166     
167     extern __inline__ void __cli(void)
168     {
169     	unsigned long tmp;
170     
171     	__asm__ __volatile__("
172     		rd	%%psr, %0
173     		nop; nop; nop;		/* Sun4m + Cypress + SMP bug */
174     		or	%0, %1, %0
175     		wr	%0, 0x0, %%psr
176     		nop; nop; nop
177     "		: "=r" (tmp)
178     		: "i" (PSR_PIL)
179     		: "memory");
180     }
181     
182     extern __inline__ void __sti(void)
183     {
184     	unsigned long tmp;
185     
186     	__asm__ __volatile__("
187     		rd	%%psr, %0	
188     		nop; nop; nop;		/* Sun4m + Cypress + SMP bug */
189     		andn	%0, %1, %0
190     		wr	%0, 0x0, %%psr
191     		nop; nop; nop
192     "		: "=r" (tmp)
193     		: "i" (PSR_PIL)
194     		: "memory");
195     }
196     
197     extern __inline__ unsigned long getipl(void)
198     {
199     	unsigned long retval;
200     
201     	__asm__ __volatile__("rd	%%psr, %0" : "=r" (retval));
202     	return retval;
203     }
204     
205     extern __inline__ unsigned long swap_pil(unsigned long __new_psr)
206     {
207     	unsigned long retval;
208     
209     	__asm__ __volatile__("
210     		rd	%%psr, %0
211     		nop; nop; nop;		/* Sun4m + Cypress + SMP bug */
212     		and	%0, %2, %%g1
213     		and	%1, %2, %%g2
214     		xorcc	%%g1, %%g2, %%g0
215     		be	1f
216     		 nop
217     		wr	%0, %2, %%psr
218     		nop; nop; nop;
219     1:
220     "		: "=r" (retval)
221     		: "r" (__new_psr), "i" (PSR_PIL)
222     		: "g1", "g2", "memory", "cc");
223     
224     	return retval;
225     }
226     
227     extern __inline__ unsigned long read_psr_and_cli(void)
228     {
229     	unsigned long retval;
230     
231     	__asm__ __volatile__("
232     		rd	%%psr, %0
233     		nop; nop; nop;		/* Sun4m + Cypress + SMP bug */
234     		or	%0, %1, %%g1
235     		wr	%%g1, 0x0, %%psr
236     		nop; nop; nop
237     "		: "=r" (retval)
238     		: "i" (PSR_PIL)
239     		: "g1", "memory");
240     
241     	return retval;
242     }
243     
244     #define __save_flags(flags)	((flags) = getipl())
245     #define __save_and_cli(flags)	((flags) = read_psr_and_cli())
246     #define __restore_flags(flags)	setipl((flags))
247     #define local_irq_disable()		__cli()
248     #define local_irq_enable()		__sti()
249     #define local_irq_save(flags)		__save_and_cli(flags)
250     #define local_irq_restore(flags)	__restore_flags(flags)
251     
252     #ifdef CONFIG_SMP
253     
254     extern unsigned char global_irq_holder;
255     
256     #define save_and_cli(flags)   do { save_flags(flags); cli(); } while(0)
257     
258     extern void __global_cli(void);
259     extern void __global_sti(void);
260     extern unsigned long __global_save_flags(void);
261     extern void __global_restore_flags(unsigned long flags);
262     #define cli()			__global_cli()
263     #define sti()			__global_sti()
264     #define save_flags(flags)	((flags)=__global_save_flags())
265     #define restore_flags(flags)	__global_restore_flags(flags)
266     
267     #else
268     
269     #define cli() __cli()
270     #define sti() __sti()
271     #define save_flags(x) __save_flags(x)
272     #define restore_flags(x) __restore_flags(x)
273     #define save_and_cli(x) __save_and_cli(x)
274     
275     #endif
276     
277     /* XXX Change this if we ever use a PSO mode kernel. */
278     #define mb()	__asm__ __volatile__ ("" : : : "memory")
279     #define rmb()	mb()
280     #define wmb()	mb()
281     #define set_mb(__var, __value)  do { __var = __value; mb(); } while(0)
282     #define set_wmb(__var, __value) set_mb(__var, __value)
283     #define smp_mb()	__asm__ __volatile__("":::"memory");
284     #define smp_rmb()	__asm__ __volatile__("":::"memory");
285     #define smp_wmb()	__asm__ __volatile__("":::"memory");
286     
287     #define nop() __asm__ __volatile__ ("nop");
288     
289     /* This has special calling conventions */
290     #ifndef CONFIG_SMP
291     BTFIXUPDEF_CALL(void, ___xchg32, void)
292     #endif
293     
294     extern __inline__ unsigned long xchg_u32(__volatile__ unsigned long *m, unsigned long val)
295     {
296     #ifdef CONFIG_SMP
297     	__asm__ __volatile__("swap [%2], %0"
298     			     : "=&r" (val)
299     			     : "0" (val), "r" (m));
300     	return val;
301     #else
302     	register unsigned long *ptr asm("g1");
303     	register unsigned long ret asm("g2");
304     
305     	ptr = (unsigned long *) m;
306     	ret = val;
307     
308     	/* Note: this is magic and the nop there is
309     	   really needed. */
310     	__asm__ __volatile__("
311     	mov	%%o7, %%g4
312     	call	___f____xchg32
313     	 nop
314     "	: "=&r" (ret)
315     	: "0" (ret), "r" (ptr)
316     	: "g3", "g4", "g7", "memory", "cc");
317     
318     	return ret;
319     #endif
320     }
321     
322     #define xchg(ptr,x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))
323     #define tas(ptr) (xchg((ptr),1))
324     
325     extern void __xchg_called_with_bad_pointer(void);
326     
327     static __inline__ unsigned long __xchg(unsigned long x, __volatile__ void * ptr, int size)
328     {
329     	switch (size) {
330     	case 4:
331     		return xchg_u32(ptr, x);
332     	};
333     	__xchg_called_with_bad_pointer();
334     	return x;
335     }
336     
337     extern void die_if_kernel(char *str, struct pt_regs *regs) __attribute__ ((noreturn));
338     
339     #endif /* __KERNEL__ */
340     
341     #endif /* __ASSEMBLY__ */
342     
343     #endif /* !(__SPARC_SYSTEM_H) */
344