1/*
2 * include/asm-sh/processor.h
3 *
4 * Copyright (C) 1999, 2000  Niibe Yutaka
5 */
6
7#ifndef __ASM_SH_PROCESSOR_H
8#define __ASM_SH_PROCESSOR_H
9
10#include <asm/page.h>
11#include <asm/types.h>
12#include <linux/threads.h>
13
14/*
15 * Default implementation of macro that returns current
16 * instruction pointer ("program counter").
17 */
18#define current_text_addr() ({ void *pc; __asm__("mova	1f, %0\n1:":"=z" (pc)); pc; })
19
20/*
21 *  CPU type and hardware bug flags. Kept separately for each CPU.
22 */
23enum cpu_type {
24	CPU_SH7708,		/* Represents 7707, 7708, 7708S, 7708R, 7709 */
25	CPU_SH7729,		/* Represents 7709A, 7729 */
26	CPU_SH7750,     /* Represents 7750, 7751 */
27	CPU_ST40STB1,
28	CPU_SH_NONE
29};
30
31struct sh_cpuinfo {
32	enum cpu_type type;
33	char	hard_math;
34	unsigned long loops_per_jiffy;
35
36	unsigned int cpu_clock, master_clock, bus_clock, module_clock;
37#ifdef CONFIG_CPU_SUBTYPE_ST40STB1
38	unsigned int memory_clock;
39#endif
40};
41
42extern struct sh_cpuinfo boot_cpu_data;
43
44#define cpu_data (&boot_cpu_data)
45#define current_cpu_data boot_cpu_data
46
47/*
48 * User space process size: 2GB.
49 *
50 * Since SH7709 and SH7750 have "area 7", we can't use 0x7c000000--0x7fffffff
51 */
52#define TASK_SIZE	0x7c000000UL
53
54/* This decides where the kernel will search for a free chunk of vm
55 * space during mmap's.
56 */
57#define TASK_UNMAPPED_BASE	(TASK_SIZE / 3)
58
59/*
60 * Bit of SR register
61 *
62 * FD-bit:
63 *     When it's set, it means the processor doesn't have right to use FPU,
64 *     and it results exception when the floating operation is executed.
65 *
66 * IMASK-bit:
67 *     Interrupt level mask
68 */
69#define SR_FD    0x00008000
70#define SR_IMASK 0x000000f0
71
72/*
73 * FPU structure and data
74 */
75
76struct sh_fpu_hard_struct {
77	unsigned long fp_regs[16];
78	unsigned long xfp_regs[16];
79	unsigned long fpscr;
80	unsigned long fpul;
81
82	long status; /* software status information */
83};
84
85/* Dummy fpu emulator  */
86struct sh_fpu_soft_struct {
87	unsigned long fp_regs[16];
88	unsigned long xfp_regs[16];
89	unsigned long fpscr;
90	unsigned long fpul;
91
92	unsigned char lookahead;
93	unsigned long entry_pc;
94};
95
96union sh_fpu_union {
97	struct sh_fpu_hard_struct hard;
98	struct sh_fpu_soft_struct soft;
99};
100
101struct thread_struct {
102	unsigned long sp;
103	unsigned long pc;
104
105	unsigned long trap_no, error_code;
106	unsigned long address;
107	/* Hardware debugging registers may come here */
108
109	/* floating point info */
110	union sh_fpu_union fpu;
111};
112
113#define INIT_THREAD  {						\
114	sizeof(init_stack) + (long) &init_stack, /* sp */	\
115	0,					 /* pc */	\
116	0, 0, 							\
117	0, 							\
118	{{{0,}},} 				/* fpu state */	\
119}
120
121/*
122 * Do necessary setup to start up a newly executed thread.
123 */
124#define start_thread(regs, new_pc, new_sp)	 \
125	set_fs(USER_DS);			 \
126	regs->pr = 0;   		 	 \
127	regs->sr = 0;		/* User mode. */ \
128	regs->pc = new_pc;			 \
129	regs->regs[15] = new_sp
130
131/* Forward declaration, a strange C thing */
132struct task_struct;
133struct mm_struct;
134
135/* Free all resources held by a thread. */
136extern void release_thread(struct task_struct *);
137/*
138 * create a kernel thread without removing it from tasklists
139 */
140extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
141
142/*
143 * Bus types
144 */
145#define EISA_bus 0
146#define EISA_bus__is_a_macro /* for versions in ksyms.c */
147#define MCA_bus 0
148#define MCA_bus__is_a_macro /* for versions in ksyms.c */
149
150
151/* Copy and release all segment info associated with a VM */
152#define copy_segments(p, mm)	do { } while(0)
153#define release_segments(mm)	do { } while(0)
154
155/*
156 * FPU lazy state save handling.
157 */
158
159static __inline__ void release_fpu(void)
160{
161	unsigned long __dummy;
162
163	/* Set FD flag in SR */
164	__asm__ __volatile__("stc	sr, %0\n\t"
165			     "or	%1, %0\n\t"
166			     "ldc	%0, sr"
167			     : "=&r" (__dummy)
168			     : "r" (SR_FD));
169}
170
171static __inline__ void grab_fpu(void)
172{
173	unsigned long __dummy;
174
175	/* Clear out FD flag in SR */
176	__asm__ __volatile__("stc	sr, %0\n\t"
177			     "and	%1, %0\n\t"
178			     "ldc	%0, sr"
179			     : "=&r" (__dummy)
180			     : "r" (~SR_FD));
181}
182
183extern void save_fpu(struct task_struct *__tsk);
184
185#define unlazy_fpu(tsk) do { 			\
186	if ((tsk)->flags & PF_USEDFPU) {	\
187		grab_fpu();			\
188		save_fpu(tsk); 			\
189	}					\
190} while (0)
191
192#define clear_fpu(tsk) do { 			\
193	if ((tsk)->flags & PF_USEDFPU)	 	\
194		(tsk)->flags &= ~PF_USEDFPU; 	\
195} while (0)
196
197/* Double presision, NANS as NANS, rounding to nearest, no exceptions */
198#define FPSCR_INIT  0x00080000
199
200/*
201 * Return saved PC of a blocked thread.
202 */
203static __inline__ unsigned long thread_saved_pc(struct thread_struct *t)
204{
205	return t->pc;
206}
207
208extern unsigned long get_wchan(struct task_struct *p);
209
210#define KSTK_EIP(tsk)  ((tsk)->thread.pc)
211#define KSTK_ESP(tsk)  ((tsk)->thread.sp)
212
213#define THREAD_SIZE (2*PAGE_SIZE)
214extern struct task_struct * alloc_task_struct(void);
215extern void free_task_struct(struct task_struct *);
216#define get_task_struct(tsk)      atomic_inc(&virt_to_page(tsk)->count)
217
218#define init_task	(init_task_union.task)
219#define init_stack	(init_task_union.stack)
220
221#define cpu_relax()	do { } while (0)
222
223#endif /* __ASM_SH_PROCESSOR_H */
224