1 #ifndef __ASM_SH_PROCESSOR_64_H
2 #define __ASM_SH_PROCESSOR_64_H
3 
4 /*
5  * include/asm-sh/processor_64.h
6  *
7  * Copyright (C) 2000, 2001  Paolo Alberelli
8  * Copyright (C) 2003  Paul Mundt
9  * Copyright (C) 2004  Richard Curnow
10  *
11  * This file is subject to the terms and conditions of the GNU General Public
12  * License.  See the file "COPYING" in the main directory of this archive
13  * for more details.
14  */
15 #ifndef __ASSEMBLY__
16 
17 #include <linux/compiler.h>
18 #include <asm/page.h>
19 #include <asm/types.h>
20 #include <cpu/registers.h>
21 
22 /*
23  * Default implementation of macro that returns current
24  * instruction pointer ("program counter").
25  */
26 #define current_text_addr() ({ \
27 void *pc; \
28 unsigned long long __dummy = 0; \
29 __asm__("gettr	tr0, %1\n\t" \
30 	"pta	4, tr0\n\t" \
31 	"gettr	tr0, %0\n\t" \
32 	"ptabs	%1, tr0\n\t"	\
33 	:"=r" (pc), "=r" (__dummy) \
34 	: "1" (__dummy)); \
35 pc; })
36 
37 #endif
38 
39 /*
40  * User space process size: 2GB - 4k.
41  */
42 #define TASK_SIZE	0x7ffff000UL
43 
44 #define STACK_TOP	TASK_SIZE
45 #define STACK_TOP_MAX	STACK_TOP
46 
47 /* This decides where the kernel will search for a free chunk of vm
48  * space during mmap's.
49  */
50 #define TASK_UNMAPPED_BASE	(TASK_SIZE / 3)
51 
52 /*
53  * Bit of SR register
54  *
55  * FD-bit:
56  *     When it's set, it means the processor doesn't have right to use FPU,
57  *     and it results exception when the floating operation is executed.
58  *
59  * IMASK-bit:
60  *     Interrupt level mask
61  *
62  * STEP-bit:
63  *     Single step bit
64  *
65  */
66 #if defined(CONFIG_SH64_SR_WATCH)
67 #define SR_MMU   0x84000000
68 #else
69 #define SR_MMU   0x80000000
70 #endif
71 
72 #define SR_IMASK 0x000000f0
73 #define SR_FD    0x00008000
74 #define SR_SSTEP 0x08000000
75 
76 #ifndef __ASSEMBLY__
77 
78 /*
79  * FPU structure and data : require 8-byte alignment as we need to access it
80    with fld.p, fst.p
81  */
82 
83 struct sh_fpu_hard_struct {
84 	unsigned long fp_regs[64];
85 	unsigned int fpscr;
86 	/* long status; * software status information */
87 };
88 
89 /* Dummy fpu emulator  */
90 struct sh_fpu_soft_struct {
91 	unsigned long fp_regs[64];
92 	unsigned int fpscr;
93 	unsigned char lookahead;
94 	unsigned long entry_pc;
95 };
96 
97 union thread_xstate {
98 	struct sh_fpu_hard_struct hardfpu;
99 	struct sh_fpu_soft_struct softfpu;
100 	/*
101 	 * The structure definitions only produce 32 bit alignment, yet we need
102 	 * to access them using 64 bit load/store as well.
103 	 */
104 	unsigned long long alignment_dummy;
105 };
106 
107 struct thread_struct {
108 	unsigned long sp;
109 	unsigned long pc;
110 
111 	/* Various thread flags, see SH_THREAD_xxx */
112 	unsigned long flags;
113 
114 	/* This stores the address of the pt_regs built during a context
115 	   switch, or of the register save area built for a kernel mode
116 	   exception.  It is used for backtracing the stack of a sleeping task
117 	   or one that traps in kernel mode. */
118         struct pt_regs *kregs;
119 	/* This stores the address of the pt_regs constructed on entry from
120 	   user mode.  It is a fixed value over the lifetime of a process, or
121 	   NULL for a kernel thread. */
122 	struct pt_regs *uregs;
123 
124 	unsigned long trap_no, error_code;
125 	unsigned long address;
126 	/* Hardware debugging registers may come here */
127 
128 	/* floating point info */
129 	union thread_xstate *xstate;
130 };
131 
132 #define INIT_MMAP \
133 { &init_mm, 0, 0, NULL, PAGE_SHARED, VM_READ | VM_WRITE | VM_EXEC, 1, NULL, NULL }
134 
135 #define INIT_THREAD  {				\
136 	.sp		= sizeof(init_stack) +	\
137 			  (long) &init_stack,	\
138 	.pc		= 0,			\
139         .kregs		= &fake_swapper_regs,	\
140 	.uregs	        = NULL,			\
141 	.trap_no	= 0,			\
142 	.error_code	= 0,			\
143 	.address	= 0,			\
144 	.flags		= 0,			\
145 }
146 
147 /*
148  * Do necessary setup to start up a newly executed thread.
149  */
150 #define SR_USER (SR_MMU | SR_FD)
151 
152 #define start_thread(_regs, new_pc, new_sp)			\
153 	set_fs(USER_DS);					\
154 	_regs->sr = SR_USER;	/* User mode. */		\
155 	_regs->pc = new_pc - 4;	/* Compensate syscall exit */	\
156 	_regs->pc |= 1;		/* Set SHmedia ! */		\
157 	_regs->regs[18] = 0;					\
158 	_regs->regs[15] = new_sp
159 
160 /* Forward declaration, a strange C thing */
161 struct task_struct;
162 struct mm_struct;
163 
164 /* Free all resources held by a thread. */
165 extern void release_thread(struct task_struct *);
166 /*
167  * create a kernel thread without removing it from tasklists
168  */
169 extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
170 
171 
172 /* Copy and release all segment info associated with a VM */
173 #define copy_segments(p, mm)	do { } while (0)
174 #define release_segments(mm)	do { } while (0)
175 #define forget_segments()	do { } while (0)
176 #define prepare_to_copy(tsk)	do { } while (0)
177 /*
178  * FPU lazy state save handling.
179  */
180 
disable_fpu(void)181 static inline void disable_fpu(void)
182 {
183 	unsigned long long __dummy;
184 
185 	/* Set FD flag in SR */
186 	__asm__ __volatile__("getcon	" __SR ", %0\n\t"
187 			     "or	%0, %1, %0\n\t"
188 			     "putcon	%0, " __SR "\n\t"
189 			     : "=&r" (__dummy)
190 			     : "r" (SR_FD));
191 }
192 
enable_fpu(void)193 static inline void enable_fpu(void)
194 {
195 	unsigned long long __dummy;
196 
197 	/* Clear out FD flag in SR */
198 	__asm__ __volatile__("getcon	" __SR ", %0\n\t"
199 			     "and	%0, %1, %0\n\t"
200 			     "putcon	%0, " __SR "\n\t"
201 			     : "=&r" (__dummy)
202 			     : "r" (~SR_FD));
203 }
204 
205 /* Round to nearest, no exceptions on inexact, overflow, underflow,
206    zero-divide, invalid.  Configure option for whether to flush denorms to
207    zero, or except if a denorm is encountered.  */
208 #if defined(CONFIG_SH64_FPU_DENORM_FLUSH)
209 #define FPSCR_INIT  0x00040000
210 #else
211 #define FPSCR_INIT  0x00000000
212 #endif
213 
214 #ifdef CONFIG_SH_FPU
215 /* Initialise the FP state of a task */
216 void fpinit(struct sh_fpu_hard_struct *fpregs);
217 #else
218 #define fpinit(fpregs)	do { } while (0)
219 #endif
220 
221 extern struct task_struct *last_task_used_math;
222 
223 /*
224  * Return saved PC of a blocked thread.
225  */
226 #define thread_saved_pc(tsk)	(tsk->thread.pc)
227 
228 extern unsigned long get_wchan(struct task_struct *p);
229 
230 #define KSTK_EIP(tsk)  ((tsk)->thread.pc)
231 #define KSTK_ESP(tsk)  ((tsk)->thread.sp)
232 
233 #endif	/* __ASSEMBLY__ */
234 #endif /* __ASM_SH_PROCESSOR_64_H */
235