xref: /openbmc/linux/arch/sh/include/asm/processor_32.h (revision b6dcefde)
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 
18 /*
19  * Default implementation of macro that returns current
20  * instruction pointer ("program counter").
21  */
22 #define current_text_addr() ({ void *pc; __asm__("mova	1f, %0\n.align 2\n1:":"=z" (pc)); pc; })
23 
24 /* Core Processor Version Register */
25 #define CCN_PVR		0xff000030
26 #define CCN_CVR		0xff000040
27 #define CCN_PRR		0xff000044
28 
29 asmlinkage void __init sh_cpu_init(void);
30 
31 /*
32  * User space process size: 2GB.
33  *
34  * Since SH7709 and SH7750 have "area 7", we can't use 0x7c000000--0x7fffffff
35  */
36 #define TASK_SIZE	0x7c000000UL
37 
38 #define STACK_TOP	TASK_SIZE
39 #define STACK_TOP_MAX	STACK_TOP
40 
41 /* This decides where the kernel will search for a free chunk of vm
42  * space during mmap's.
43  */
44 #define TASK_UNMAPPED_BASE	(TASK_SIZE / 3)
45 
46 /*
47  * Bit of SR register
48  *
49  * FD-bit:
50  *     When it's set, it means the processor doesn't have right to use FPU,
51  *     and it results exception when the floating operation is executed.
52  *
53  * IMASK-bit:
54  *     Interrupt level mask
55  */
56 #define SR_DSP		0x00001000
57 #define SR_IMASK	0x000000f0
58 #define SR_FD		0x00008000
59 #define SR_MD		0x40000000
60 
61 /*
62  * DSP structure and data
63  */
64 struct sh_dsp_struct {
65 	unsigned long dsp_regs[14];
66 	long status;
67 };
68 
69 /*
70  * FPU structure and data
71  */
72 
73 struct sh_fpu_hard_struct {
74 	unsigned long fp_regs[16];
75 	unsigned long xfp_regs[16];
76 	unsigned long fpscr;
77 	unsigned long fpul;
78 
79 	long status; /* software status information */
80 };
81 
82 /* Dummy fpu emulator  */
83 struct sh_fpu_soft_struct {
84 	unsigned long fp_regs[16];
85 	unsigned long xfp_regs[16];
86 	unsigned long fpscr;
87 	unsigned long fpul;
88 
89 	unsigned char lookahead;
90 	unsigned long entry_pc;
91 };
92 
93 union sh_fpu_union {
94 	struct sh_fpu_hard_struct hard;
95 	struct sh_fpu_soft_struct soft;
96 };
97 
98 struct thread_struct {
99 	/* Saved registers when thread is descheduled */
100 	unsigned long sp;
101 	unsigned long pc;
102 
103 	/* Hardware debugging registers */
104 	unsigned long ubc_pc;
105 
106 	/* floating point info */
107 	union sh_fpu_union fpu;
108 
109 #ifdef CONFIG_SH_DSP
110 	/* Dsp status information */
111 	struct sh_dsp_struct dsp_status;
112 #endif
113 };
114 
115 /* Count of active tasks with UBC settings */
116 extern int ubc_usercnt;
117 
118 #define INIT_THREAD  {						\
119 	.sp = sizeof(init_stack) + (long) &init_stack,		\
120 }
121 
122 /*
123  * Do necessary setup to start up a newly executed thread.
124  */
125 #define start_thread(_regs, new_pc, new_sp)	 \
126 	set_fs(USER_DS);			 \
127 	_regs->pr = 0;				 \
128 	_regs->sr = SR_FD;	/* User mode. */ \
129 	_regs->pc = new_pc;			 \
130 	_regs->regs[15] = new_sp
131 
132 /* Forward declaration, a strange C thing */
133 struct task_struct;
134 struct mm_struct;
135 
136 /* Free all resources held by a thread. */
137 extern void release_thread(struct task_struct *);
138 
139 /* Prepare to copy thread state - unlazy all lazy status */
140 void prepare_to_copy(struct task_struct *tsk);
141 
142 /*
143  * create a kernel thread without removing it from tasklists
144  */
145 extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
146 
147 /* Copy and release all segment info associated with a VM */
148 #define copy_segments(p, mm)	do { } while(0)
149 #define release_segments(mm)	do { } while(0)
150 
151 /*
152  * FPU lazy state save handling.
153  */
154 
155 static __inline__ void disable_fpu(void)
156 {
157 	unsigned long __dummy;
158 
159 	/* Set FD flag in SR */
160 	__asm__ __volatile__("stc	sr, %0\n\t"
161 			     "or	%1, %0\n\t"
162 			     "ldc	%0, sr"
163 			     : "=&r" (__dummy)
164 			     : "r" (SR_FD));
165 }
166 
167 static __inline__ void enable_fpu(void)
168 {
169 	unsigned long __dummy;
170 
171 	/* Clear out FD flag in SR */
172 	__asm__ __volatile__("stc	sr, %0\n\t"
173 			     "and	%1, %0\n\t"
174 			     "ldc	%0, sr"
175 			     : "=&r" (__dummy)
176 			     : "r" (~SR_FD));
177 }
178 
179 /* Double presision, NANS as NANS, rounding to nearest, no exceptions */
180 #define FPSCR_INIT  0x00080000
181 
182 #define	FPSCR_CAUSE_MASK	0x0001f000	/* Cause bits */
183 #define	FPSCR_FLAG_MASK		0x0000007c	/* Flag bits */
184 
185 /*
186  * Return saved PC of a blocked thread.
187  */
188 #define thread_saved_pc(tsk)	(tsk->thread.pc)
189 
190 void show_trace(struct task_struct *tsk, unsigned long *sp,
191 		struct pt_regs *regs);
192 
193 #ifdef CONFIG_DUMP_CODE
194 void show_code(struct pt_regs *regs);
195 #else
196 static inline void show_code(struct pt_regs *regs)
197 {
198 }
199 #endif
200 
201 extern unsigned long get_wchan(struct task_struct *p);
202 
203 #define KSTK_EIP(tsk)  (task_pt_regs(tsk)->pc)
204 #define KSTK_ESP(tsk)  (task_pt_regs(tsk)->regs[15])
205 
206 #define user_stack_pointer(_regs)	((_regs)->regs[15])
207 
208 #if defined(CONFIG_CPU_SH2A) || defined(CONFIG_CPU_SH4)
209 #define PREFETCH_STRIDE		L1_CACHE_BYTES
210 #define ARCH_HAS_PREFETCH
211 #define ARCH_HAS_PREFETCHW
212 static inline void prefetch(void *x)
213 {
214 	__asm__ __volatile__ ("pref @%0\n\t" : : "r" (x) : "memory");
215 }
216 
217 #define prefetchw(x)	prefetch(x)
218 #endif
219 
220 #endif /* __KERNEL__ */
221 #endif /* __ASM_SH_PROCESSOR_32_H */
222