1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * include/asm/processor.h
4  *
5  * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
6  */
7 
8 #ifndef __ASM_SPARC64_PROCESSOR_H
9 #define __ASM_SPARC64_PROCESSOR_H
10 
11 #include <asm/asi.h>
12 #include <asm/pstate.h>
13 #include <asm/ptrace.h>
14 #include <asm/page.h>
15 
16 /*
17  * User lives in his very own context, and cannot reference us. Note
18  * that TASK_SIZE is a misnomer, it really gives maximum user virtual
19  * address that the kernel will allocate out.
20  *
21  * XXX No longer using virtual page tables, kill this upper limit...
22  */
23 #define VA_BITS		44
24 #ifndef __ASSEMBLY__
25 #define VPTE_SIZE	(1UL << (VA_BITS - PAGE_SHIFT + 3))
26 #else
27 #define VPTE_SIZE	(1 << (VA_BITS - PAGE_SHIFT + 3))
28 #endif
29 
30 #define TASK_SIZE_OF(tsk) \
31 	(test_tsk_thread_flag(tsk,TIF_32BIT) ? \
32 	 (1UL << 32UL) : ((unsigned long)-VPTE_SIZE))
33 #define TASK_SIZE \
34 	(test_thread_flag(TIF_32BIT) ? \
35 	 (1UL << 32UL) : ((unsigned long)-VPTE_SIZE))
36 #ifdef __KERNEL__
37 
38 #define STACK_TOP32	((1UL << 32UL) - PAGE_SIZE)
39 #define STACK_TOP64	(0x0000080000000000UL - (1UL << 32UL))
40 
41 #define STACK_TOP	(test_thread_flag(TIF_32BIT) ? \
42 			 STACK_TOP32 : STACK_TOP64)
43 
44 #define STACK_TOP_MAX	STACK_TOP64
45 
46 #endif
47 
48 #ifndef __ASSEMBLY__
49 
50 typedef struct {
51 	unsigned char seg;
52 } mm_segment_t;
53 
54 /* The Sparc processor specific thread struct. */
55 /* XXX This should die, everything can go into thread_info now. */
56 struct thread_struct {
57 #ifdef CONFIG_DEBUG_SPINLOCK
58 	/* How many spinlocks held by this thread.
59 	 * Used with spin lock debugging to catch tasks
60 	 * sleeping illegally with locks held.
61 	 */
62 	int smp_lock_count;
63 	unsigned int smp_lock_pc;
64 #else
65 	int dummy; /* f'in gcc bug... */
66 #endif
67 };
68 
69 #endif /* !(__ASSEMBLY__) */
70 
71 #ifndef CONFIG_DEBUG_SPINLOCK
72 #define INIT_THREAD  {			\
73 	0,				\
74 }
75 #else /* CONFIG_DEBUG_SPINLOCK */
76 #define INIT_THREAD  {					\
77 /* smp_lock_count, smp_lock_pc, */			\
78    0,		   0,					\
79 }
80 #endif /* !(CONFIG_DEBUG_SPINLOCK) */
81 
82 #ifndef __ASSEMBLY__
83 
84 #include <linux/types.h>
85 #include <asm/fpumacro.h>
86 
87 struct task_struct;
88 
89 /* On Uniprocessor, even in RMO processes see TSO semantics */
90 #ifdef CONFIG_SMP
91 #define TSTATE_INITIAL_MM	TSTATE_TSO
92 #else
93 #define TSTATE_INITIAL_MM	TSTATE_RMO
94 #endif
95 
96 /* Do necessary setup to start up a newly executed thread. */
97 #define start_thread(regs, pc, sp) \
98 do { \
99 	unsigned long __asi = ASI_PNF; \
100 	regs->tstate = (regs->tstate & (TSTATE_CWP)) | (TSTATE_INITIAL_MM|TSTATE_IE) | (__asi << 24UL); \
101 	regs->tpc = ((pc & (~3)) - 4); \
102 	regs->tnpc = regs->tpc + 4; \
103 	regs->y = 0; \
104 	set_thread_wstate(1 << 3); \
105 	if (current_thread_info()->utraps) { \
106 		if (*(current_thread_info()->utraps) < 2) \
107 			kfree(current_thread_info()->utraps); \
108 		else \
109 			(*(current_thread_info()->utraps))--; \
110 		current_thread_info()->utraps = NULL; \
111 	} \
112 	__asm__ __volatile__( \
113 	"stx		%%g0, [%0 + %2 + 0x00]\n\t" \
114 	"stx		%%g0, [%0 + %2 + 0x08]\n\t" \
115 	"stx		%%g0, [%0 + %2 + 0x10]\n\t" \
116 	"stx		%%g0, [%0 + %2 + 0x18]\n\t" \
117 	"stx		%%g0, [%0 + %2 + 0x20]\n\t" \
118 	"stx		%%g0, [%0 + %2 + 0x28]\n\t" \
119 	"stx		%%g0, [%0 + %2 + 0x30]\n\t" \
120 	"stx		%%g0, [%0 + %2 + 0x38]\n\t" \
121 	"stx		%%g0, [%0 + %2 + 0x40]\n\t" \
122 	"stx		%%g0, [%0 + %2 + 0x48]\n\t" \
123 	"stx		%%g0, [%0 + %2 + 0x50]\n\t" \
124 	"stx		%%g0, [%0 + %2 + 0x58]\n\t" \
125 	"stx		%%g0, [%0 + %2 + 0x60]\n\t" \
126 	"stx		%%g0, [%0 + %2 + 0x68]\n\t" \
127 	"stx		%1,   [%0 + %2 + 0x70]\n\t" \
128 	"stx		%%g0, [%0 + %2 + 0x78]\n\t" \
129 	"wrpr		%%g0, (1 << 3), %%wstate\n\t" \
130 	: \
131 	: "r" (regs), "r" (sp - sizeof(struct reg_window) - STACK_BIAS), \
132 	  "i" ((const unsigned long)(&((struct pt_regs *)0)->u_regs[0]))); \
133 	fprs_write(0);	\
134 	current_thread_info()->xfsr[0] = 0;	\
135 	current_thread_info()->fpsaved[0] = 0;	\
136 	regs->tstate &= ~TSTATE_PEF;	\
137 } while (0)
138 
139 #define start_thread32(regs, pc, sp) \
140 do { \
141 	unsigned long __asi = ASI_PNF; \
142 	pc &= 0x00000000ffffffffUL; \
143 	sp &= 0x00000000ffffffffUL; \
144 	regs->tstate = (regs->tstate & (TSTATE_CWP))|(TSTATE_INITIAL_MM|TSTATE_IE|TSTATE_AM) | (__asi << 24UL); \
145 	regs->tpc = ((pc & (~3)) - 4); \
146 	regs->tnpc = regs->tpc + 4; \
147 	regs->y = 0; \
148 	set_thread_wstate(2 << 3); \
149 	if (current_thread_info()->utraps) { \
150 		if (*(current_thread_info()->utraps) < 2) \
151 			kfree(current_thread_info()->utraps); \
152 		else \
153 			(*(current_thread_info()->utraps))--; \
154 		current_thread_info()->utraps = NULL; \
155 	} \
156 	__asm__ __volatile__( \
157 	"stx		%%g0, [%0 + %2 + 0x00]\n\t" \
158 	"stx		%%g0, [%0 + %2 + 0x08]\n\t" \
159 	"stx		%%g0, [%0 + %2 + 0x10]\n\t" \
160 	"stx		%%g0, [%0 + %2 + 0x18]\n\t" \
161 	"stx		%%g0, [%0 + %2 + 0x20]\n\t" \
162 	"stx		%%g0, [%0 + %2 + 0x28]\n\t" \
163 	"stx		%%g0, [%0 + %2 + 0x30]\n\t" \
164 	"stx		%%g0, [%0 + %2 + 0x38]\n\t" \
165 	"stx		%%g0, [%0 + %2 + 0x40]\n\t" \
166 	"stx		%%g0, [%0 + %2 + 0x48]\n\t" \
167 	"stx		%%g0, [%0 + %2 + 0x50]\n\t" \
168 	"stx		%%g0, [%0 + %2 + 0x58]\n\t" \
169 	"stx		%%g0, [%0 + %2 + 0x60]\n\t" \
170 	"stx		%%g0, [%0 + %2 + 0x68]\n\t" \
171 	"stx		%1,   [%0 + %2 + 0x70]\n\t" \
172 	"stx		%%g0, [%0 + %2 + 0x78]\n\t" \
173 	"wrpr		%%g0, (2 << 3), %%wstate\n\t" \
174 	: \
175 	: "r" (regs), "r" (sp - sizeof(struct reg_window32)), \
176 	  "i" ((const unsigned long)(&((struct pt_regs *)0)->u_regs[0]))); \
177 	fprs_write(0);	\
178 	current_thread_info()->xfsr[0] = 0;	\
179 	current_thread_info()->fpsaved[0] = 0;	\
180 	regs->tstate &= ~TSTATE_PEF;	\
181 } while (0)
182 
183 /* Free all resources held by a thread. */
184 #define release_thread(tsk)		do { } while (0)
185 
186 unsigned long __get_wchan(struct task_struct *task);
187 
188 #define task_pt_regs(tsk) (task_thread_info(tsk)->kregs)
189 #define KSTK_EIP(tsk)  (task_pt_regs(tsk)->tpc)
190 #define KSTK_ESP(tsk)  (task_pt_regs(tsk)->u_regs[UREG_FP])
191 
192 /* Please see the commentary in asm/backoff.h for a description of
193  * what these instructions are doing and how they have been chosen.
194  * To make a long story short, we are trying to yield the current cpu
195  * strand during busy loops.
196  */
197 #ifdef	BUILD_VDSO
198 #define	cpu_relax()	asm volatile("\n99:\n\t"			\
199 				     "rd	%%ccr, %%g0\n\t"	\
200 				     "rd	%%ccr, %%g0\n\t"	\
201 				     "rd	%%ccr, %%g0\n\t"	\
202 				     ::: "memory")
203 #else /* ! BUILD_VDSO */
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 #endif
216 
217 /* Prefetch support.  This is tuned for UltraSPARC-III and later.
218  * UltraSPARC-I will treat these as nops, and UltraSPARC-II has
219  * a shallower prefetch queue than later chips.
220  */
221 #define ARCH_HAS_PREFETCH
222 #define ARCH_HAS_PREFETCHW
223 #define ARCH_HAS_SPINLOCK_PREFETCH
224 
225 static inline void prefetch(const void *x)
226 {
227 	/* We do not use the read prefetch mnemonic because that
228 	 * prefetches into the prefetch-cache which only is accessible
229 	 * by floating point operations in UltraSPARC-III and later.
230 	 * By contrast, "#one_write" prefetches into the L2 cache
231 	 * in shared state.
232 	 */
233 	__asm__ __volatile__("prefetch [%0], #one_write"
234 			     : /* no outputs */
235 			     : "r" (x));
236 }
237 
238 static inline void prefetchw(const void *x)
239 {
240 	/* The most optimal prefetch to use for writes is
241 	 * "#n_writes".  This brings the cacheline into the
242 	 * L2 cache in "owned" state.
243 	 */
244 	__asm__ __volatile__("prefetch [%0], #n_writes"
245 			     : /* no outputs */
246 			     : "r" (x));
247 }
248 
249 #define spin_lock_prefetch(x)	prefetchw(x)
250 
251 #define HAVE_ARCH_PICK_MMAP_LAYOUT
252 
253 int do_mathemu(struct pt_regs *regs, struct fpustate *f, bool illegal_insn_trap);
254 
255 #endif /* !(__ASSEMBLY__) */
256 
257 #endif /* !(__ASM_SPARC64_PROCESSOR_H) */
258