1 /*
2  * include/asm/processor.h
3  *
4  * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
5  */
6 
7 #ifndef __ASM_SPARC64_PROCESSOR_H
8 #define __ASM_SPARC64_PROCESSOR_H
9 
10 /*
11  * Sparc64 implementation of macro that returns current
12  * instruction pointer ("program counter").
13  */
14 #define current_text_addr() ({ void *pc; __asm__("rd %%pc, %0" : "=r" (pc)); pc; })
15 
16 #include <asm/asi.h>
17 #include <asm/pstate.h>
18 #include <asm/ptrace.h>
19 #include <asm/page.h>
20 
21 /*
22  * User lives in his very own context, and cannot reference us. Note
23  * that TASK_SIZE is a misnomer, it really gives maximum user virtual
24  * address that the kernel will allocate out.
25  *
26  * XXX No longer using virtual page tables, kill this upper limit...
27  */
28 #define VA_BITS		44
29 #ifndef __ASSEMBLY__
30 #define VPTE_SIZE	(1UL << (VA_BITS - PAGE_SHIFT + 3))
31 #else
32 #define VPTE_SIZE	(1 << (VA_BITS - PAGE_SHIFT + 3))
33 #endif
34 
35 #define TASK_SIZE_OF(tsk) \
36 	(test_tsk_thread_flag(tsk,TIF_32BIT) ? \
37 	 (1UL << 32UL) : ((unsigned long)-VPTE_SIZE))
38 #define TASK_SIZE \
39 	(test_thread_flag(TIF_32BIT) ? \
40 	 (1UL << 32UL) : ((unsigned long)-VPTE_SIZE))
41 #ifdef __KERNEL__
42 
43 #define STACK_TOP32	((1UL << 32UL) - PAGE_SIZE)
44 #define STACK_TOP64	(0x0000080000000000UL - (1UL << 32UL))
45 
46 #define STACK_TOP	(test_thread_flag(TIF_32BIT) ? \
47 			 STACK_TOP32 : STACK_TOP64)
48 
49 #define STACK_TOP_MAX	STACK_TOP64
50 
51 #endif
52 
53 #ifndef __ASSEMBLY__
54 
55 typedef struct {
56 	unsigned char seg;
57 } mm_segment_t;
58 
59 /* The Sparc processor specific thread struct. */
60 /* XXX This should die, everything can go into thread_info now. */
61 struct thread_struct {
62 #ifdef CONFIG_DEBUG_SPINLOCK
63 	/* How many spinlocks held by this thread.
64 	 * Used with spin lock debugging to catch tasks
65 	 * sleeping illegally with locks held.
66 	 */
67 	int smp_lock_count;
68 	unsigned int smp_lock_pc;
69 #else
70 	int dummy; /* f'in gcc bug... */
71 #endif
72 };
73 
74 #endif /* !(__ASSEMBLY__) */
75 
76 #ifndef CONFIG_DEBUG_SPINLOCK
77 #define INIT_THREAD  {			\
78 	0,				\
79 }
80 #else /* CONFIG_DEBUG_SPINLOCK */
81 #define INIT_THREAD  {					\
82 /* smp_lock_count, smp_lock_pc, */			\
83    0,		   0,					\
84 }
85 #endif /* !(CONFIG_DEBUG_SPINLOCK) */
86 
87 #ifndef __ASSEMBLY__
88 
89 #include <linux/types.h>
90 #include <asm/fpumacro.h>
91 
92 /* Return saved PC of a blocked thread. */
93 struct task_struct;
94 unsigned long thread_saved_pc(struct task_struct *);
95 
96 /* On Uniprocessor, even in RMO processes see TSO semantics */
97 #ifdef CONFIG_SMP
98 #define TSTATE_INITIAL_MM	TSTATE_TSO
99 #else
100 #define TSTATE_INITIAL_MM	TSTATE_RMO
101 #endif
102 
103 /* Do necessary setup to start up a newly executed thread. */
104 #define start_thread(regs, pc, sp) \
105 do { \
106 	unsigned long __asi = ASI_PNF; \
107 	regs->tstate = (regs->tstate & (TSTATE_CWP)) | (TSTATE_INITIAL_MM|TSTATE_IE) | (__asi << 24UL); \
108 	regs->tpc = ((pc & (~3)) - 4); \
109 	regs->tnpc = regs->tpc + 4; \
110 	regs->y = 0; \
111 	set_thread_wstate(1 << 3); \
112 	if (current_thread_info()->utraps) { \
113 		if (*(current_thread_info()->utraps) < 2) \
114 			kfree(current_thread_info()->utraps); \
115 		else \
116 			(*(current_thread_info()->utraps))--; \
117 		current_thread_info()->utraps = NULL; \
118 	} \
119 	__asm__ __volatile__( \
120 	"stx		%%g0, [%0 + %2 + 0x00]\n\t" \
121 	"stx		%%g0, [%0 + %2 + 0x08]\n\t" \
122 	"stx		%%g0, [%0 + %2 + 0x10]\n\t" \
123 	"stx		%%g0, [%0 + %2 + 0x18]\n\t" \
124 	"stx		%%g0, [%0 + %2 + 0x20]\n\t" \
125 	"stx		%%g0, [%0 + %2 + 0x28]\n\t" \
126 	"stx		%%g0, [%0 + %2 + 0x30]\n\t" \
127 	"stx		%%g0, [%0 + %2 + 0x38]\n\t" \
128 	"stx		%%g0, [%0 + %2 + 0x40]\n\t" \
129 	"stx		%%g0, [%0 + %2 + 0x48]\n\t" \
130 	"stx		%%g0, [%0 + %2 + 0x50]\n\t" \
131 	"stx		%%g0, [%0 + %2 + 0x58]\n\t" \
132 	"stx		%%g0, [%0 + %2 + 0x60]\n\t" \
133 	"stx		%%g0, [%0 + %2 + 0x68]\n\t" \
134 	"stx		%1,   [%0 + %2 + 0x70]\n\t" \
135 	"stx		%%g0, [%0 + %2 + 0x78]\n\t" \
136 	"wrpr		%%g0, (1 << 3), %%wstate\n\t" \
137 	: \
138 	: "r" (regs), "r" (sp - sizeof(struct reg_window) - STACK_BIAS), \
139 	  "i" ((const unsigned long)(&((struct pt_regs *)0)->u_regs[0]))); \
140 	fprs_write(0);	\
141 	current_thread_info()->xfsr[0] = 0;	\
142 	current_thread_info()->fpsaved[0] = 0;	\
143 	regs->tstate &= ~TSTATE_PEF;	\
144 } while (0)
145 
146 #define start_thread32(regs, pc, sp) \
147 do { \
148 	unsigned long __asi = ASI_PNF; \
149 	pc &= 0x00000000ffffffffUL; \
150 	sp &= 0x00000000ffffffffUL; \
151 	regs->tstate = (regs->tstate & (TSTATE_CWP))|(TSTATE_INITIAL_MM|TSTATE_IE|TSTATE_AM) | (__asi << 24UL); \
152 	regs->tpc = ((pc & (~3)) - 4); \
153 	regs->tnpc = regs->tpc + 4; \
154 	regs->y = 0; \
155 	set_thread_wstate(2 << 3); \
156 	if (current_thread_info()->utraps) { \
157 		if (*(current_thread_info()->utraps) < 2) \
158 			kfree(current_thread_info()->utraps); \
159 		else \
160 			(*(current_thread_info()->utraps))--; \
161 		current_thread_info()->utraps = NULL; \
162 	} \
163 	__asm__ __volatile__( \
164 	"stx		%%g0, [%0 + %2 + 0x00]\n\t" \
165 	"stx		%%g0, [%0 + %2 + 0x08]\n\t" \
166 	"stx		%%g0, [%0 + %2 + 0x10]\n\t" \
167 	"stx		%%g0, [%0 + %2 + 0x18]\n\t" \
168 	"stx		%%g0, [%0 + %2 + 0x20]\n\t" \
169 	"stx		%%g0, [%0 + %2 + 0x28]\n\t" \
170 	"stx		%%g0, [%0 + %2 + 0x30]\n\t" \
171 	"stx		%%g0, [%0 + %2 + 0x38]\n\t" \
172 	"stx		%%g0, [%0 + %2 + 0x40]\n\t" \
173 	"stx		%%g0, [%0 + %2 + 0x48]\n\t" \
174 	"stx		%%g0, [%0 + %2 + 0x50]\n\t" \
175 	"stx		%%g0, [%0 + %2 + 0x58]\n\t" \
176 	"stx		%%g0, [%0 + %2 + 0x60]\n\t" \
177 	"stx		%%g0, [%0 + %2 + 0x68]\n\t" \
178 	"stx		%1,   [%0 + %2 + 0x70]\n\t" \
179 	"stx		%%g0, [%0 + %2 + 0x78]\n\t" \
180 	"wrpr		%%g0, (2 << 3), %%wstate\n\t" \
181 	: \
182 	: "r" (regs), "r" (sp - sizeof(struct reg_window32)), \
183 	  "i" ((const unsigned long)(&((struct pt_regs *)0)->u_regs[0]))); \
184 	fprs_write(0);	\
185 	current_thread_info()->xfsr[0] = 0;	\
186 	current_thread_info()->fpsaved[0] = 0;	\
187 	regs->tstate &= ~TSTATE_PEF;	\
188 } while (0)
189 
190 /* Free all resources held by a thread. */
191 #define release_thread(tsk)		do { } while (0)
192 
193 unsigned long get_wchan(struct task_struct *task);
194 
195 #define task_pt_regs(tsk) (task_thread_info(tsk)->kregs)
196 #define KSTK_EIP(tsk)  (task_pt_regs(tsk)->tpc)
197 #define KSTK_ESP(tsk)  (task_pt_regs(tsk)->u_regs[UREG_FP])
198 
199 /* Please see the commentary in asm/backoff.h for a description of
200  * what these instructions are doing and how they have been chosen.
201  * To make a long story short, we are trying to yield the current cpu
202  * strand during busy loops.
203  */
204 #define cpu_relax()	asm volatile("\n99:\n\t"			\
205 				     "rd	%%ccr, %%g0\n\t"	\
206 				     "rd	%%ccr, %%g0\n\t"	\
207 				     "rd	%%ccr, %%g0\n\t"	\
208 				     ".section	.pause_3insn_patch,\"ax\"\n\t"\
209 				     ".word	99b\n\t"		\
210 				     "wr	%%g0, 128, %%asr27\n\t"	\
211 				     "nop\n\t"				\
212 				     "nop\n\t"				\
213 				     ".previous"			\
214 				     ::: "memory")
215 
216 /* Prefetch support.  This is tuned for UltraSPARC-III and later.
217  * UltraSPARC-I will treat these as nops, and UltraSPARC-II has
218  * a shallower prefetch queue than later chips.
219  */
220 #define ARCH_HAS_PREFETCH
221 #define ARCH_HAS_PREFETCHW
222 #define ARCH_HAS_SPINLOCK_PREFETCH
223 
224 static inline void prefetch(const void *x)
225 {
226 	/* We do not use the read prefetch mnemonic because that
227 	 * prefetches into the prefetch-cache which only is accessible
228 	 * by floating point operations in UltraSPARC-III and later.
229 	 * By contrast, "#one_write" prefetches into the L2 cache
230 	 * in shared state.
231 	 */
232 	__asm__ __volatile__("prefetch [%0], #one_write"
233 			     : /* no outputs */
234 			     : "r" (x));
235 }
236 
237 static inline void prefetchw(const void *x)
238 {
239 	/* The most optimal prefetch to use for writes is
240 	 * "#n_writes".  This brings the cacheline into the
241 	 * L2 cache in "owned" state.
242 	 */
243 	__asm__ __volatile__("prefetch [%0], #n_writes"
244 			     : /* no outputs */
245 			     : "r" (x));
246 }
247 
248 #define spin_lock_prefetch(x)	prefetchw(x)
249 
250 #define HAVE_ARCH_PICK_MMAP_LAYOUT
251 
252 int do_mathemu(struct pt_regs *regs, struct fpustate *f, bool illegal_insn_trap);
253 
254 #endif /* !(__ASSEMBLY__) */
255 
256 #endif /* !(__ASM_SPARC64_PROCESSOR_H) */
257