xref: /openbmc/linux/arch/s390/include/asm/processor.h (revision 63dc02bd)
1 /*
2  *  include/asm-s390/processor.h
3  *
4  *  S390 version
5  *    Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
6  *    Author(s): Hartmut Penner (hp@de.ibm.com),
7  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
8  *
9  *  Derived from "include/asm-i386/processor.h"
10  *    Copyright (C) 1994, Linus Torvalds
11  */
12 
13 #ifndef __ASM_S390_PROCESSOR_H
14 #define __ASM_S390_PROCESSOR_H
15 
16 #include <linux/linkage.h>
17 #include <linux/irqflags.h>
18 #include <asm/cpu.h>
19 #include <asm/page.h>
20 #include <asm/ptrace.h>
21 #include <asm/setup.h>
22 
23 #ifdef __KERNEL__
24 /*
25  * Default implementation of macro that returns current
26  * instruction pointer ("program counter").
27  */
28 #define current_text_addr() ({ void *pc; asm("basr %0,0" : "=a" (pc)); pc; })
29 
30 static inline void get_cpu_id(struct cpuid *ptr)
31 {
32 	asm volatile("stidp %0" : "=Q" (*ptr));
33 }
34 
35 extern void s390_adjust_jiffies(void);
36 extern int get_cpu_capability(unsigned int *);
37 extern const struct seq_operations cpuinfo_op;
38 extern int sysctl_ieee_emulation_warnings;
39 
40 /*
41  * User space process size: 2GB for 31 bit, 4TB or 8PT for 64 bit.
42  */
43 #ifndef __s390x__
44 
45 #define TASK_SIZE		(1UL << 31)
46 #define TASK_UNMAPPED_BASE	(1UL << 30)
47 
48 #else /* __s390x__ */
49 
50 #define TASK_SIZE_OF(tsk)	((tsk)->mm->context.asce_limit)
51 #define TASK_UNMAPPED_BASE	(test_thread_flag(TIF_31BIT) ? \
52 					(1UL << 30) : (1UL << 41))
53 #define TASK_SIZE		TASK_SIZE_OF(current)
54 
55 #endif /* __s390x__ */
56 
57 #ifdef __KERNEL__
58 
59 #ifndef __s390x__
60 #define STACK_TOP		(1UL << 31)
61 #define STACK_TOP_MAX		(1UL << 31)
62 #else /* __s390x__ */
63 #define STACK_TOP		(1UL << (test_thread_flag(TIF_31BIT) ? 31:42))
64 #define STACK_TOP_MAX		(1UL << 42)
65 #endif /* __s390x__ */
66 
67 
68 #endif
69 
70 #define HAVE_ARCH_PICK_MMAP_LAYOUT
71 
72 typedef struct {
73         __u32 ar4;
74 } mm_segment_t;
75 
76 /*
77  * Thread structure
78  */
79 struct thread_struct {
80 	s390_fp_regs fp_regs;
81 	unsigned int  acrs[NUM_ACRS];
82         unsigned long ksp;              /* kernel stack pointer             */
83 	mm_segment_t mm_segment;
84 	unsigned long gmap_addr;	/* address of last gmap fault. */
85 	struct per_regs per_user;	/* User specified PER registers */
86 	struct per_event per_event;	/* Cause of the last PER trap */
87         /* pfault_wait is used to block the process on a pfault event */
88 	unsigned long pfault_wait;
89 	struct list_head list;
90 };
91 
92 typedef struct thread_struct thread_struct;
93 
94 /*
95  * Stack layout of a C stack frame.
96  */
97 #ifndef __PACK_STACK
98 struct stack_frame {
99 	unsigned long back_chain;
100 	unsigned long empty1[5];
101 	unsigned long gprs[10];
102 	unsigned int  empty2[8];
103 };
104 #else
105 struct stack_frame {
106 	unsigned long empty1[5];
107 	unsigned int  empty2[8];
108 	unsigned long gprs[10];
109 	unsigned long back_chain;
110 };
111 #endif
112 
113 #define ARCH_MIN_TASKALIGN	8
114 
115 #define INIT_THREAD {							\
116 	.ksp = sizeof(init_stack) + (unsigned long) &init_stack,	\
117 }
118 
119 /*
120  * Do necessary setup to start up a new thread.
121  */
122 #define start_thread(regs, new_psw, new_stackp) do {			\
123 	regs->psw.mask	= psw_user_bits | PSW_MASK_EA | PSW_MASK_BA;	\
124 	regs->psw.addr	= new_psw | PSW_ADDR_AMODE;			\
125 	regs->gprs[15]	= new_stackp;					\
126 } while (0)
127 
128 #define start_thread31(regs, new_psw, new_stackp) do {			\
129 	regs->psw.mask	= psw_user_bits | PSW_MASK_BA;			\
130 	regs->psw.addr	= new_psw | PSW_ADDR_AMODE;			\
131 	regs->gprs[15]	= new_stackp;					\
132 	crst_table_downgrade(current->mm, 1UL << 31);			\
133 } while (0)
134 
135 /* Forward declaration, a strange C thing */
136 struct task_struct;
137 struct mm_struct;
138 struct seq_file;
139 
140 /* Free all resources held by a thread. */
141 extern void release_thread(struct task_struct *);
142 extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
143 
144 /* Prepare to copy thread state - unlazy all lazy status */
145 #define prepare_to_copy(tsk)	do { } while (0)
146 
147 /*
148  * Return saved PC of a blocked thread.
149  */
150 extern unsigned long thread_saved_pc(struct task_struct *t);
151 
152 extern void show_code(struct pt_regs *regs);
153 
154 unsigned long get_wchan(struct task_struct *p);
155 #define task_pt_regs(tsk) ((struct pt_regs *) \
156         (task_stack_page(tsk) + THREAD_SIZE) - 1)
157 #define KSTK_EIP(tsk)	(task_pt_regs(tsk)->psw.addr)
158 #define KSTK_ESP(tsk)	(task_pt_regs(tsk)->gprs[15])
159 
160 static inline unsigned short stap(void)
161 {
162 	unsigned short cpu_address;
163 
164 	asm volatile("stap %0" : "=m" (cpu_address));
165 	return cpu_address;
166 }
167 
168 /*
169  * Give up the time slice of the virtual PU.
170  */
171 static inline void cpu_relax(void)
172 {
173 	if (MACHINE_HAS_DIAG44)
174 		asm volatile("diag 0,0,68");
175 	barrier();
176 }
177 
178 static inline void psw_set_key(unsigned int key)
179 {
180 	asm volatile("spka 0(%0)" : : "d" (key));
181 }
182 
183 /*
184  * Set PSW to specified value.
185  */
186 static inline void __load_psw(psw_t psw)
187 {
188 #ifndef __s390x__
189 	asm volatile("lpsw  %0" : : "Q" (psw) : "cc");
190 #else
191 	asm volatile("lpswe %0" : : "Q" (psw) : "cc");
192 #endif
193 }
194 
195 /*
196  * Set PSW mask to specified value, while leaving the
197  * PSW addr pointing to the next instruction.
198  */
199 static inline void __load_psw_mask (unsigned long mask)
200 {
201 	unsigned long addr;
202 	psw_t psw;
203 
204 	psw.mask = mask;
205 
206 #ifndef __s390x__
207 	asm volatile(
208 		"	basr	%0,0\n"
209 		"0:	ahi	%0,1f-0b\n"
210 		"	st	%0,%O1+4(%R1)\n"
211 		"	lpsw	%1\n"
212 		"1:"
213 		: "=&d" (addr), "=Q" (psw) : "Q" (psw) : "memory", "cc");
214 #else /* __s390x__ */
215 	asm volatile(
216 		"	larl	%0,1f\n"
217 		"	stg	%0,%O1+8(%R1)\n"
218 		"	lpswe	%1\n"
219 		"1:"
220 		: "=&d" (addr), "=Q" (psw) : "Q" (psw) : "memory", "cc");
221 #endif /* __s390x__ */
222 }
223 
224 /*
225  * Rewind PSW instruction address by specified number of bytes.
226  */
227 static inline unsigned long __rewind_psw(psw_t psw, unsigned long ilc)
228 {
229 #ifndef __s390x__
230 	if (psw.addr & PSW_ADDR_AMODE)
231 		/* 31 bit mode */
232 		return (psw.addr - ilc) | PSW_ADDR_AMODE;
233 	/* 24 bit mode */
234 	return (psw.addr - ilc) & ((1UL << 24) - 1);
235 #else
236 	unsigned long mask;
237 
238 	mask = (psw.mask & PSW_MASK_EA) ? -1UL :
239 	       (psw.mask & PSW_MASK_BA) ? (1UL << 31) - 1 :
240 					  (1UL << 24) - 1;
241 	return (psw.addr - ilc) & mask;
242 #endif
243 }
244 
245 /*
246  * Function to drop a processor into disabled wait state
247  */
248 static inline void __noreturn disabled_wait(unsigned long code)
249 {
250         unsigned long ctl_buf;
251         psw_t dw_psw;
252 
253 	dw_psw.mask = PSW_MASK_BASE | PSW_MASK_WAIT | PSW_MASK_BA | PSW_MASK_EA;
254         dw_psw.addr = code;
255         /*
256          * Store status and then load disabled wait psw,
257          * the processor is dead afterwards
258          */
259 #ifndef __s390x__
260 	asm volatile(
261 		"	stctl	0,0,0(%2)\n"
262 		"	ni	0(%2),0xef\n"	/* switch off protection */
263 		"	lctl	0,0,0(%2)\n"
264 		"	stpt	0xd8\n"		/* store timer */
265 		"	stckc	0xe0\n"		/* store clock comparator */
266 		"	stpx	0x108\n"	/* store prefix register */
267 		"	stam	0,15,0x120\n"	/* store access registers */
268 		"	std	0,0x160\n"	/* store f0 */
269 		"	std	2,0x168\n"	/* store f2 */
270 		"	std	4,0x170\n"	/* store f4 */
271 		"	std	6,0x178\n"	/* store f6 */
272 		"	stm	0,15,0x180\n"	/* store general registers */
273 		"	stctl	0,15,0x1c0\n"	/* store control registers */
274 		"	oi	0x1c0,0x10\n"	/* fake protection bit */
275 		"	lpsw	0(%1)"
276 		: "=m" (ctl_buf)
277 		: "a" (&dw_psw), "a" (&ctl_buf), "m" (dw_psw) : "cc");
278 #else /* __s390x__ */
279 	asm volatile(
280 		"	stctg	0,0,0(%2)\n"
281 		"	ni	4(%2),0xef\n"	/* switch off protection */
282 		"	lctlg	0,0,0(%2)\n"
283 		"	lghi	1,0x1000\n"
284 		"	stpt	0x328(1)\n"	/* store timer */
285 		"	stckc	0x330(1)\n"	/* store clock comparator */
286 		"	stpx	0x318(1)\n"	/* store prefix register */
287 		"	stam	0,15,0x340(1)\n"/* store access registers */
288 		"	stfpc	0x31c(1)\n"	/* store fpu control */
289 		"	std	0,0x200(1)\n"	/* store f0 */
290 		"	std	1,0x208(1)\n"	/* store f1 */
291 		"	std	2,0x210(1)\n"	/* store f2 */
292 		"	std	3,0x218(1)\n"	/* store f3 */
293 		"	std	4,0x220(1)\n"	/* store f4 */
294 		"	std	5,0x228(1)\n"	/* store f5 */
295 		"	std	6,0x230(1)\n"	/* store f6 */
296 		"	std	7,0x238(1)\n"	/* store f7 */
297 		"	std	8,0x240(1)\n"	/* store f8 */
298 		"	std	9,0x248(1)\n"	/* store f9 */
299 		"	std	10,0x250(1)\n"	/* store f10 */
300 		"	std	11,0x258(1)\n"	/* store f11 */
301 		"	std	12,0x260(1)\n"	/* store f12 */
302 		"	std	13,0x268(1)\n"	/* store f13 */
303 		"	std	14,0x270(1)\n"	/* store f14 */
304 		"	std	15,0x278(1)\n"	/* store f15 */
305 		"	stmg	0,15,0x280(1)\n"/* store general registers */
306 		"	stctg	0,15,0x380(1)\n"/* store control registers */
307 		"	oi	0x384(1),0x10\n"/* fake protection bit */
308 		"	lpswe	0(%1)"
309 		: "=m" (ctl_buf)
310 		: "a" (&dw_psw), "a" (&ctl_buf), "m" (dw_psw) : "cc", "0", "1");
311 #endif /* __s390x__ */
312 	while (1);
313 }
314 
315 /*
316  * Use to set psw mask except for the first byte which
317  * won't be changed by this function.
318  */
319 static inline void
320 __set_psw_mask(unsigned long mask)
321 {
322 	__load_psw_mask(mask | (arch_local_save_flags() & ~(-1UL >> 8)));
323 }
324 
325 #define local_mcck_enable() \
326 	__set_psw_mask(psw_kernel_bits | PSW_MASK_DAT | PSW_MASK_MCHECK)
327 #define local_mcck_disable() \
328 	__set_psw_mask(psw_kernel_bits | PSW_MASK_DAT)
329 
330 /*
331  * Basic Machine Check/Program Check Handler.
332  */
333 
334 extern void s390_base_mcck_handler(void);
335 extern void s390_base_pgm_handler(void);
336 extern void s390_base_ext_handler(void);
337 
338 extern void (*s390_base_mcck_handler_fn)(void);
339 extern void (*s390_base_pgm_handler_fn)(void);
340 extern void (*s390_base_ext_handler_fn)(void);
341 
342 #define ARCH_LOW_ADDRESS_LIMIT	0x7fffffffUL
343 
344 #endif
345 
346 /*
347  * Helper macro for exception table entries
348  */
349 #ifndef __s390x__
350 #define EX_TABLE(_fault,_target)			\
351 	".section __ex_table,\"a\"\n"			\
352 	"	.align 4\n"				\
353 	"	.long  " #_fault "," #_target "\n"	\
354 	".previous\n"
355 #else
356 #define EX_TABLE(_fault,_target)			\
357 	".section __ex_table,\"a\"\n"			\
358 	"	.align 8\n"				\
359 	"	.quad  " #_fault "," #_target "\n"	\
360 	".previous\n"
361 #endif
362 
363 #endif                                 /* __ASM_S390_PROCESSOR_H           */
364