1 /* $Id: processor.h,v 1.83 2001/10/08 09:32:13 davem Exp $
2  * include/asm-sparc/processor.h
3  *
4  * Copyright (C) 1994 David S. Miller (davem@caip.rutgers.edu)
5  */
6 
7 #ifndef __ASM_SPARC_PROCESSOR_H
8 #define __ASM_SPARC_PROCESSOR_H
9 
10 /*
11  * Sparc32 implementation of macro that returns current
12  * instruction pointer ("program counter").
13  */
14 #define current_text_addr() ({ void *pc; __asm__("sethi %%hi(1f), %0; or %0, %%lo(1f), %0;\n1:" : "=r" (pc)); pc; })
15 
16 #include <linux/a.out.h>
17 
18 #include <asm/psr.h>
19 #include <asm/ptrace.h>
20 #include <asm/head.h>
21 #include <asm/signal.h>
22 #include <asm/segment.h>
23 #include <asm/btfixup.h>
24 #include <asm/page.h>
25 #include <asm/atomic.h>
26 
27 /*
28  * Bus types
29  */
30 #define EISA_bus 0
31 #define EISA_bus__is_a_macro /* for versions in ksyms.c */
32 #define MCA_bus 0
33 #define MCA_bus__is_a_macro /* for versions in ksyms.c */
34 
35 /*
36  * The sparc has no problems with write protection
37  */
38 #define wp_works_ok 1
39 #define wp_works_ok__is_a_macro /* for versions in ksyms.c */
40 
41 /* Whee, this is STACK_TOP + PAGE_SIZE and the lowest kernel address too...
42  * That one page is used to protect kernel from intruders, so that
43  * we can make our access_ok test faster
44  */
45 #define TASK_SIZE	PAGE_OFFSET
46 
47 struct fpq {
48 	unsigned long *insn_addr;
49 	unsigned long insn;
50 };
51 
52 typedef struct {
53 	int seg;
54 } mm_segment_t;
55 
56 /* The Sparc processor specific thread struct. */
57 struct thread_struct {
58 	unsigned long uwinmask __attribute__ ((aligned (8)));
59 	struct pt_regs *kregs;
60 
61 	/* Context switch saved kernel state. */
62 	unsigned long ksp __attribute__ ((aligned (8)));
63 	unsigned long kpc;
64 	unsigned long kpsr;
65 	unsigned long kwim;
66 
67 	/* Special child fork kpsr/kwim values. */
68 	unsigned long fork_kpsr __attribute__ ((aligned (8)));
69 	unsigned long fork_kwim;
70 
71 	/* A place to store user windows and stack pointers
72 	 * when the stack needs inspection.
73 	 */
74 #define NSWINS 8
75 	struct reg_window reg_window[NSWINS] __attribute__ ((aligned (8)));
76 	unsigned long rwbuf_stkptrs[NSWINS] __attribute__ ((aligned (8)));
77 	unsigned long w_saved;
78 
79 	/* Floating point regs */
80 	unsigned long   float_regs[32] __attribute__ ((aligned (8)));
81 	unsigned long   fsr;
82 	unsigned long   fpqdepth;
83 	struct fpq	fpqueue[16];
84 	unsigned long flags;
85 	mm_segment_t current_ds;
86 	struct exec core_exec;     /* just what it says. */
87 	int new_signal;
88 	atomic_t refcount;	/* used for sun4c only */
89 };
90 
91 #define SPARC_FLAG_KTHREAD      0x1    /* task is a kernel thread */
92 #define SPARC_FLAG_UNALIGNED    0x2    /* is allowed to do unaligned accesses */
93 
94 #define INIT_THREAD  { \
95 /* uwinmask, kregs, ksp, kpc, kpsr, kwim */ \
96    0,        0,     0,   0,   0,    0, \
97 /* fork_kpsr, fork_kwim */ \
98    0,         0, \
99 /* reg_window */  \
100 { { { 0, }, { 0, } }, }, \
101 /* rwbuf_stkptrs */  \
102 { 0, 0, 0, 0, 0, 0, 0, 0, }, \
103 /* w_saved */ \
104    0, \
105 /* FPU regs */   { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, \
106                    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, }, \
107 /* FPU status, FPU qdepth, FPU queue */ \
108    0,          0,  { { 0, 0, }, }, \
109 /* flags,              current_ds, */ \
110    SPARC_FLAG_KTHREAD, KERNEL_DS, \
111 /* core_exec */ \
112 { 0, }, \
113 /* new_signal */ \
114   0, \
115 }
116 
117 /* Return saved PC of a blocked thread. */
thread_saved_pc(struct thread_struct * t)118 extern __inline__ unsigned long thread_saved_pc(struct thread_struct *t)
119 {
120 	return t->kpc;
121 }
122 
123 /* Do necessary setup to start up a newly executed thread. */
start_thread(struct pt_regs * regs,unsigned long pc,unsigned long sp)124 extern __inline__ void start_thread(struct pt_regs * regs, unsigned long pc,
125 				    unsigned long sp)
126 {
127 	register unsigned long zero asm("g1");
128 
129 	regs->psr = (regs->psr & (PSR_CWP)) | PSR_S;
130 	regs->pc = ((pc & (~3)) - 4);
131 	regs->npc = regs->pc + 4;
132 	regs->y = 0;
133 	zero = 0;
134 	__asm__ __volatile__("std\t%%g0, [%0 + %3 + 0x00]\n\t"
135 			     "std\t%%g0, [%0 + %3 + 0x08]\n\t"
136 			     "std\t%%g0, [%0 + %3 + 0x10]\n\t"
137 			     "std\t%%g0, [%0 + %3 + 0x18]\n\t"
138 			     "std\t%%g0, [%0 + %3 + 0x20]\n\t"
139 			     "std\t%%g0, [%0 + %3 + 0x28]\n\t"
140 			     "std\t%%g0, [%0 + %3 + 0x30]\n\t"
141 			     "st\t%1, [%0 + %3 + 0x38]\n\t"
142 			     "st\t%%g0, [%0 + %3 + 0x3c]"
143 			     : /* no outputs */
144 			     : "r" (regs),
145 			       "r" (sp - sizeof(struct reg_window)),
146 			       "r" (zero),
147 			       "i" ((const unsigned long)(&((struct pt_regs *)0)->u_regs[0]))
148 			     : "memory");
149 }
150 
151 /* Free all resources held by a thread. */
152 #define release_thread(tsk)		do { } while(0)
153 extern pid_t arch_kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
154 
155 
156 #define copy_segments(tsk, mm)		do { } while (0)
157 #define release_segments(mm)		do { } while (0)
158 
159 #define get_wchan(__TSK) \
160 ({	extern void scheduling_functions_start_here(void); \
161 	extern void scheduling_functions_end_here(void); \
162 	unsigned long pc, fp, bias = 0; \
163 	unsigned long task_base = (unsigned long) (__TSK); \
164         unsigned long __ret = 0; \
165 	struct reg_window *rw; \
166 	int count = 0; \
167 	if (!(__TSK) || (__TSK) == current || \
168             (__TSK)->state == TASK_RUNNING) \
169 		goto __out; \
170 	fp = (__TSK)->thread.ksp + bias; \
171 	do { \
172 		/* Bogus frame pointer? */ \
173 		if (fp < (task_base + sizeof(struct task_struct)) || \
174 		    fp >= (task_base + (2 * PAGE_SIZE))) \
175 			break; \
176 		rw = (struct reg_window *) fp; \
177 		pc = rw->ins[7]; \
178 		if (pc < ((unsigned long) scheduling_functions_start_here) || \
179                     pc >= ((unsigned long) scheduling_functions_end_here)) { \
180 			__ret = pc; \
181 			goto __out; \
182 		} \
183 		fp = rw->ins[6] + bias; \
184 	} while (++count < 16); \
185 __out:	__ret; \
186 })
187 
188 #define KSTK_EIP(tsk)  ((tsk)->thread.kregs->pc)
189 #define KSTK_ESP(tsk)  ((tsk)->thread.kregs->u_regs[UREG_FP])
190 
191 #ifdef __KERNEL__
192 #define THREAD_SIZE (2*PAGE_SIZE)
193 
194 extern struct task_struct *last_task_used_math;
195 
196 /* Allocation and freeing of basic task resources. */
197 BTFIXUPDEF_CALL(struct task_struct *, alloc_task_struct, void)
198 BTFIXUPDEF_CALL(void, free_task_struct, struct task_struct *)
199 BTFIXUPDEF_CALL(void, get_task_struct, struct task_struct *)
200 
201 #define alloc_task_struct() BTFIXUP_CALL(alloc_task_struct)()
202 #define free_task_struct(tsk) BTFIXUP_CALL(free_task_struct)(tsk)
203 #define get_task_struct(tsk) BTFIXUP_CALL(get_task_struct)(tsk)
204 
205 #define init_task	(init_task_union.task)
206 #define init_stack	(init_task_union.stack)
207 
208 #define cpu_relax()	barrier()
209 
210 #endif
211 
212 #endif /* __ASM_SPARC_PROCESSOR_H */
213