xref: /linux/arch/sh/include/asm/processor_32.h (revision 7025bec9125b0a02edcaf22c2dce753bf2c95480)
1 /*
2  * include/asm-sh/processor.h
3  *
4  * Copyright (C) 1999, 2000  Niibe Yutaka
5  * Copyright (C) 2002, 2003  Paul Mundt
6  */
7 
8 #ifndef __ASM_SH_PROCESSOR_32_H
9 #define __ASM_SH_PROCESSOR_32_H
10 #ifdef __KERNEL__
11 
12 #include <linux/compiler.h>
13 #include <linux/linkage.h>
14 #include <asm/page.h>
15 #include <asm/types.h>
16 #include <asm/ptrace.h>
17 #include <asm/hw_breakpoint.h>
18 
19 /*
20  * Default implementation of macro that returns current
21  * instruction pointer ("program counter").
22  */
23 #define current_text_addr() ({ void *pc; __asm__("mova	1f, %0\n.align 2\n1:":"=z" (pc)); pc; })
24 
25 /* Core Processor Version Register */
26 #define CCN_PVR		0xff000030
27 #define CCN_CVR		0xff000040
28 #define CCN_PRR		0xff000044
29 
30 asmlinkage void __init sh_cpu_init(void);
31 
32 /*
33  * User space process size: 2GB.
34  *
35  * Since SH7709 and SH7750 have "area 7", we can't use 0x7c000000--0x7fffffff
36  */
37 #define TASK_SIZE	0x7c000000UL
38 
39 #define STACK_TOP	TASK_SIZE
40 #define STACK_TOP_MAX	STACK_TOP
41 
42 /* This decides where the kernel will search for a free chunk of vm
43  * space during mmap's.
44  */
45 #define TASK_UNMAPPED_BASE	(TASK_SIZE / 3)
46 
47 /*
48  * Bit of SR register
49  *
50  * FD-bit:
51  *     When it's set, it means the processor doesn't have right to use FPU,
52  *     and it results exception when the floating operation is executed.
53  *
54  * IMASK-bit:
55  *     Interrupt level mask
56  */
57 #define SR_DSP		0x00001000
58 #define SR_IMASK	0x000000f0
59 #define SR_FD		0x00008000
60 #define SR_MD		0x40000000
61 
62 /*
63  * DSP structure and data
64  */
65 struct sh_dsp_struct {
66 	unsigned long dsp_regs[14];
67 	long status;
68 };
69 
70 /*
71  * FPU structure and data
72  */
73 
74 struct sh_fpu_hard_struct {
75 	unsigned long fp_regs[16];
76 	unsigned long xfp_regs[16];
77 	unsigned long fpscr;
78 	unsigned long fpul;
79 
80 	long status; /* software status information */
81 };
82 
83 /* Dummy fpu emulator  */
84 struct sh_fpu_soft_struct {
85 	unsigned long fp_regs[16];
86 	unsigned long xfp_regs[16];
87 	unsigned long fpscr;
88 	unsigned long fpul;
89 
90 	unsigned char lookahead;
91 	unsigned long entry_pc;
92 };
93 
94 union sh_fpu_union {
95 	struct sh_fpu_hard_struct hard;
96 	struct sh_fpu_soft_struct soft;
97 };
98 
99 struct thread_struct {
100 	/* Saved registers when thread is descheduled */
101 	unsigned long sp;
102 	unsigned long pc;
103 
104 	/* Save middle states of ptrace breakpoints */
105 	struct perf_event	*ptrace_bps[HBP_NUM];
106 
107 	/* floating point info */
108 	union sh_fpu_union fpu;
109 
110 #ifdef CONFIG_SH_DSP
111 	/* Dsp status information */
112 	struct sh_dsp_struct dsp_status;
113 #endif
114 };
115 
116 #define INIT_THREAD  {						\
117 	.sp = sizeof(init_stack) + (long) &init_stack,		\
118 }
119 
120 /*
121  * Do necessary setup to start up a newly executed thread.
122  */
123 #define start_thread(_regs, new_pc, new_sp)	 \
124 	set_fs(USER_DS);			 \
125 	_regs->pr = 0;				 \
126 	_regs->sr = SR_FD;	/* User mode. */ \
127 	_regs->pc = new_pc;			 \
128 	_regs->regs[15] = new_sp
129 
130 /* Forward declaration, a strange C thing */
131 struct task_struct;
132 struct mm_struct;
133 
134 /* Free all resources held by a thread. */
135 extern void release_thread(struct task_struct *);
136 
137 /* Prepare to copy thread state - unlazy all lazy status */
138 void prepare_to_copy(struct task_struct *tsk);
139 
140 /*
141  * create a kernel thread without removing it from tasklists
142  */
143 extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
144 
145 /* Copy and release all segment info associated with a VM */
146 #define copy_segments(p, mm)	do { } while(0)
147 #define release_segments(mm)	do { } while(0)
148 
149 /*
150  * FPU lazy state save handling.
151  */
152 
153 static __inline__ void disable_fpu(void)
154 {
155 	unsigned long __dummy;
156 
157 	/* Set FD flag in SR */
158 	__asm__ __volatile__("stc	sr, %0\n\t"
159 			     "or	%1, %0\n\t"
160 			     "ldc	%0, sr"
161 			     : "=&r" (__dummy)
162 			     : "r" (SR_FD));
163 }
164 
165 static __inline__ void enable_fpu(void)
166 {
167 	unsigned long __dummy;
168 
169 	/* Clear out FD flag in SR */
170 	__asm__ __volatile__("stc	sr, %0\n\t"
171 			     "and	%1, %0\n\t"
172 			     "ldc	%0, sr"
173 			     : "=&r" (__dummy)
174 			     : "r" (~SR_FD));
175 }
176 
177 /* Double presision, NANS as NANS, rounding to nearest, no exceptions */
178 #define FPSCR_INIT  0x00080000
179 
180 #define	FPSCR_CAUSE_MASK	0x0001f000	/* Cause bits */
181 #define	FPSCR_FLAG_MASK		0x0000007c	/* Flag bits */
182 
183 /*
184  * Return saved PC of a blocked thread.
185  */
186 #define thread_saved_pc(tsk)	(tsk->thread.pc)
187 
188 void show_trace(struct task_struct *tsk, unsigned long *sp,
189 		struct pt_regs *regs);
190 
191 #ifdef CONFIG_DUMP_CODE
192 void show_code(struct pt_regs *regs);
193 #else
194 static inline void show_code(struct pt_regs *regs)
195 {
196 }
197 #endif
198 
199 extern unsigned long get_wchan(struct task_struct *p);
200 
201 #define KSTK_EIP(tsk)  (task_pt_regs(tsk)->pc)
202 #define KSTK_ESP(tsk)  (task_pt_regs(tsk)->regs[15])
203 
204 #define user_stack_pointer(_regs)	((_regs)->regs[15])
205 
206 #if defined(CONFIG_CPU_SH2A) || defined(CONFIG_CPU_SH4)
207 #define PREFETCH_STRIDE		L1_CACHE_BYTES
208 #define ARCH_HAS_PREFETCH
209 #define ARCH_HAS_PREFETCHW
210 static inline void prefetch(void *x)
211 {
212 	__asm__ __volatile__ ("pref @%0\n\t" : : "r" (x) : "memory");
213 }
214 
215 #define prefetchw(x)	prefetch(x)
216 #endif
217 
218 #endif /* __KERNEL__ */
219 #endif /* __ASM_SH_PROCESSOR_32_H */
220