xref: /linux/arch/sh/include/asm/processor_32.h (revision cc4589ebfae6f8dbb5cf880a0a67eedab3416492)
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 /*
31  * User space process size: 2GB.
32  *
33  * Since SH7709 and SH7750 have "area 7", we can't use 0x7c000000--0x7fffffff
34  */
35 #define TASK_SIZE	0x7c000000UL
36 
37 #define STACK_TOP	TASK_SIZE
38 #define STACK_TOP_MAX	STACK_TOP
39 
40 /* This decides where the kernel will search for a free chunk of vm
41  * space during mmap's.
42  */
43 #define TASK_UNMAPPED_BASE	(TASK_SIZE / 3)
44 
45 /*
46  * Bit of SR register
47  *
48  * FD-bit:
49  *     When it's set, it means the processor doesn't have right to use FPU,
50  *     and it results exception when the floating operation is executed.
51  *
52  * IMASK-bit:
53  *     Interrupt level mask
54  */
55 #define SR_DSP		0x00001000
56 #define SR_IMASK	0x000000f0
57 #define SR_FD		0x00008000
58 #define SR_MD		0x40000000
59 
60 /*
61  * DSP structure and data
62  */
63 struct sh_dsp_struct {
64 	unsigned long dsp_regs[14];
65 	long status;
66 };
67 
68 /*
69  * FPU structure and data
70  */
71 
72 struct sh_fpu_hard_struct {
73 	unsigned long fp_regs[16];
74 	unsigned long xfp_regs[16];
75 	unsigned long fpscr;
76 	unsigned long fpul;
77 
78 	long status; /* software status information */
79 };
80 
81 /* Dummy fpu emulator  */
82 struct sh_fpu_soft_struct {
83 	unsigned long fp_regs[16];
84 	unsigned long xfp_regs[16];
85 	unsigned long fpscr;
86 	unsigned long fpul;
87 
88 	unsigned char lookahead;
89 	unsigned long entry_pc;
90 };
91 
92 union thread_xstate {
93 	struct sh_fpu_hard_struct hardfpu;
94 	struct sh_fpu_soft_struct softfpu;
95 };
96 
97 struct thread_struct {
98 	/* Saved registers when thread is descheduled */
99 	unsigned long sp;
100 	unsigned long pc;
101 
102 	/* Various thread flags, see SH_THREAD_xxx */
103 	unsigned long flags;
104 
105 	/* Save middle states of ptrace breakpoints */
106 	struct perf_event *ptrace_bps[HBP_NUM];
107 
108 #ifdef CONFIG_SH_DSP
109 	/* Dsp status information */
110 	struct sh_dsp_struct dsp_status;
111 #endif
112 
113 	/* Extended processor state */
114 	union thread_xstate *xstate;
115 };
116 
117 #define INIT_THREAD  {						\
118 	.sp = sizeof(init_stack) + (long) &init_stack,		\
119 	.flags = 0,						\
120 }
121 
122 /* Forward declaration, a strange C thing */
123 struct task_struct;
124 
125 extern void start_thread(struct pt_regs *regs, unsigned long new_pc, unsigned long new_sp);
126 
127 /* Free all resources held by a thread. */
128 extern void release_thread(struct task_struct *);
129 
130 /* Prepare to copy thread state - unlazy all lazy status */
131 void prepare_to_copy(struct task_struct *tsk);
132 
133 /*
134  * create a kernel thread without removing it from tasklists
135  */
136 extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
137 
138 /* Copy and release all segment info associated with a VM */
139 #define copy_segments(p, mm)	do { } while(0)
140 #define release_segments(mm)	do { } while(0)
141 
142 /*
143  * FPU lazy state save handling.
144  */
145 
146 static __inline__ void disable_fpu(void)
147 {
148 	unsigned long __dummy;
149 
150 	/* Set FD flag in SR */
151 	__asm__ __volatile__("stc	sr, %0\n\t"
152 			     "or	%1, %0\n\t"
153 			     "ldc	%0, sr"
154 			     : "=&r" (__dummy)
155 			     : "r" (SR_FD));
156 }
157 
158 static __inline__ void enable_fpu(void)
159 {
160 	unsigned long __dummy;
161 
162 	/* Clear out FD flag in SR */
163 	__asm__ __volatile__("stc	sr, %0\n\t"
164 			     "and	%1, %0\n\t"
165 			     "ldc	%0, sr"
166 			     : "=&r" (__dummy)
167 			     : "r" (~SR_FD));
168 }
169 
170 /* Double presision, NANS as NANS, rounding to nearest, no exceptions */
171 #define FPSCR_INIT  0x00080000
172 
173 #define	FPSCR_CAUSE_MASK	0x0001f000	/* Cause bits */
174 #define	FPSCR_FLAG_MASK		0x0000007c	/* Flag bits */
175 
176 /*
177  * Return saved PC of a blocked thread.
178  */
179 #define thread_saved_pc(tsk)	(tsk->thread.pc)
180 
181 void show_trace(struct task_struct *tsk, unsigned long *sp,
182 		struct pt_regs *regs);
183 
184 #ifdef CONFIG_DUMP_CODE
185 void show_code(struct pt_regs *regs);
186 #else
187 static inline void show_code(struct pt_regs *regs)
188 {
189 }
190 #endif
191 
192 extern unsigned long get_wchan(struct task_struct *p);
193 
194 #define KSTK_EIP(tsk)  (task_pt_regs(tsk)->pc)
195 #define KSTK_ESP(tsk)  (task_pt_regs(tsk)->regs[15])
196 
197 #define user_stack_pointer(_regs)	((_regs)->regs[15])
198 
199 #if defined(CONFIG_CPU_SH2A) || defined(CONFIG_CPU_SH4)
200 #define PREFETCH_STRIDE		L1_CACHE_BYTES
201 #define ARCH_HAS_PREFETCH
202 #define ARCH_HAS_PREFETCHW
203 static inline void prefetch(void *x)
204 {
205 	__asm__ __volatile__ ("pref @%0\n\t" : : "r" (x) : "memory");
206 }
207 
208 #define prefetchw(x)	prefetch(x)
209 #endif
210 
211 #endif /* __KERNEL__ */
212 #endif /* __ASM_SH_PROCESSOR_32_H */
213