xref: /linux/arch/s390/include/asm/processor.h (revision d89dffa976bcd13fd87eb76e02e3b71c3a7868e3)
1 /*
2  *  S390 version
3  *    Copyright IBM Corp. 1999
4  *    Author(s): Hartmut Penner (hp@de.ibm.com),
5  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
6  *
7  *  Derived from "include/asm-i386/processor.h"
8  *    Copyright (C) 1994, Linus Torvalds
9  */
10 
11 #ifndef __ASM_S390_PROCESSOR_H
12 #define __ASM_S390_PROCESSOR_H
13 
14 #include <linux/linkage.h>
15 #include <linux/irqflags.h>
16 #include <asm/cpu.h>
17 #include <asm/page.h>
18 #include <asm/ptrace.h>
19 #include <asm/setup.h>
20 
21 /*
22  * Default implementation of macro that returns current
23  * instruction pointer ("program counter").
24  */
25 #define current_text_addr() ({ void *pc; asm("basr %0,0" : "=a" (pc)); pc; })
26 
27 static inline void get_cpu_id(struct cpuid *ptr)
28 {
29 	asm volatile("stidp %0" : "=Q" (*ptr));
30 }
31 
32 extern void s390_adjust_jiffies(void);
33 extern const struct seq_operations cpuinfo_op;
34 extern int sysctl_ieee_emulation_warnings;
35 
36 /*
37  * User space process size: 2GB for 31 bit, 4TB or 8PT for 64 bit.
38  */
39 #ifndef CONFIG_64BIT
40 
41 #define TASK_SIZE		(1UL << 31)
42 #define TASK_UNMAPPED_BASE	(1UL << 30)
43 
44 #else /* CONFIG_64BIT */
45 
46 #define TASK_SIZE_OF(tsk)	((tsk)->mm->context.asce_limit)
47 #define TASK_UNMAPPED_BASE	(test_thread_flag(TIF_31BIT) ? \
48 					(1UL << 30) : (1UL << 41))
49 #define TASK_SIZE		TASK_SIZE_OF(current)
50 
51 #endif /* CONFIG_64BIT */
52 
53 #ifndef CONFIG_64BIT
54 #define STACK_TOP		(1UL << 31)
55 #define STACK_TOP_MAX		(1UL << 31)
56 #else /* CONFIG_64BIT */
57 #define STACK_TOP		(1UL << (test_thread_flag(TIF_31BIT) ? 31:42))
58 #define STACK_TOP_MAX		(1UL << 42)
59 #endif /* CONFIG_64BIT */
60 
61 #define HAVE_ARCH_PICK_MMAP_LAYOUT
62 
63 typedef struct {
64         __u32 ar4;
65 } mm_segment_t;
66 
67 /*
68  * Thread structure
69  */
70 struct thread_struct {
71 	s390_fp_regs fp_regs;
72 	unsigned int  acrs[NUM_ACRS];
73         unsigned long ksp;              /* kernel stack pointer             */
74 	mm_segment_t mm_segment;
75 	unsigned long gmap_addr;	/* address of last gmap fault. */
76 	struct per_regs per_user;	/* User specified PER registers */
77 	struct per_event per_event;	/* Cause of the last PER trap */
78         /* pfault_wait is used to block the process on a pfault event */
79 	unsigned long pfault_wait;
80 	struct list_head list;
81 };
82 
83 typedef struct thread_struct thread_struct;
84 
85 /*
86  * Stack layout of a C stack frame.
87  */
88 #ifndef __PACK_STACK
89 struct stack_frame {
90 	unsigned long back_chain;
91 	unsigned long empty1[5];
92 	unsigned long gprs[10];
93 	unsigned int  empty2[8];
94 };
95 #else
96 struct stack_frame {
97 	unsigned long empty1[5];
98 	unsigned int  empty2[8];
99 	unsigned long gprs[10];
100 	unsigned long back_chain;
101 };
102 #endif
103 
104 #define ARCH_MIN_TASKALIGN	8
105 
106 #define INIT_THREAD {							\
107 	.ksp = sizeof(init_stack) + (unsigned long) &init_stack,	\
108 }
109 
110 /*
111  * Do necessary setup to start up a new thread.
112  */
113 #define start_thread(regs, new_psw, new_stackp) do {			\
114 	regs->psw.mask	= psw_user_bits | PSW_MASK_EA | PSW_MASK_BA;	\
115 	regs->psw.addr	= new_psw | PSW_ADDR_AMODE;			\
116 	regs->gprs[15]	= new_stackp;					\
117 } while (0)
118 
119 #define start_thread31(regs, new_psw, new_stackp) do {			\
120 	regs->psw.mask	= psw_user_bits | PSW_MASK_BA;			\
121 	regs->psw.addr	= new_psw | PSW_ADDR_AMODE;			\
122 	regs->gprs[15]	= new_stackp;					\
123 	crst_table_downgrade(current->mm, 1UL << 31);			\
124 } while (0)
125 
126 /* Forward declaration, a strange C thing */
127 struct task_struct;
128 struct mm_struct;
129 struct seq_file;
130 
131 /* Free all resources held by a thread. */
132 extern void release_thread(struct task_struct *);
133 extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
134 
135 /*
136  * Return saved PC of a blocked thread.
137  */
138 extern unsigned long thread_saved_pc(struct task_struct *t);
139 
140 extern void show_code(struct pt_regs *regs);
141 
142 unsigned long get_wchan(struct task_struct *p);
143 #define task_pt_regs(tsk) ((struct pt_regs *) \
144         (task_stack_page(tsk) + THREAD_SIZE) - 1)
145 #define KSTK_EIP(tsk)	(task_pt_regs(tsk)->psw.addr)
146 #define KSTK_ESP(tsk)	(task_pt_regs(tsk)->gprs[15])
147 
148 static inline unsigned short stap(void)
149 {
150 	unsigned short cpu_address;
151 
152 	asm volatile("stap %0" : "=m" (cpu_address));
153 	return cpu_address;
154 }
155 
156 /*
157  * Give up the time slice of the virtual PU.
158  */
159 static inline void cpu_relax(void)
160 {
161 	if (MACHINE_HAS_DIAG44)
162 		asm volatile("diag 0,0,68");
163 	barrier();
164 }
165 
166 static inline void psw_set_key(unsigned int key)
167 {
168 	asm volatile("spka 0(%0)" : : "d" (key));
169 }
170 
171 /*
172  * Set PSW to specified value.
173  */
174 static inline void __load_psw(psw_t psw)
175 {
176 #ifndef CONFIG_64BIT
177 	asm volatile("lpsw  %0" : : "Q" (psw) : "cc");
178 #else
179 	asm volatile("lpswe %0" : : "Q" (psw) : "cc");
180 #endif
181 }
182 
183 /*
184  * Set PSW mask to specified value, while leaving the
185  * PSW addr pointing to the next instruction.
186  */
187 static inline void __load_psw_mask (unsigned long mask)
188 {
189 	unsigned long addr;
190 	psw_t psw;
191 
192 	psw.mask = mask;
193 
194 #ifndef CONFIG_64BIT
195 	asm volatile(
196 		"	basr	%0,0\n"
197 		"0:	ahi	%0,1f-0b\n"
198 		"	st	%0,%O1+4(%R1)\n"
199 		"	lpsw	%1\n"
200 		"1:"
201 		: "=&d" (addr), "=Q" (psw) : "Q" (psw) : "memory", "cc");
202 #else /* CONFIG_64BIT */
203 	asm volatile(
204 		"	larl	%0,1f\n"
205 		"	stg	%0,%O1+8(%R1)\n"
206 		"	lpswe	%1\n"
207 		"1:"
208 		: "=&d" (addr), "=Q" (psw) : "Q" (psw) : "memory", "cc");
209 #endif /* CONFIG_64BIT */
210 }
211 
212 /*
213  * Rewind PSW instruction address by specified number of bytes.
214  */
215 static inline unsigned long __rewind_psw(psw_t psw, unsigned long ilc)
216 {
217 #ifndef CONFIG_64BIT
218 	if (psw.addr & PSW_ADDR_AMODE)
219 		/* 31 bit mode */
220 		return (psw.addr - ilc) | PSW_ADDR_AMODE;
221 	/* 24 bit mode */
222 	return (psw.addr - ilc) & ((1UL << 24) - 1);
223 #else
224 	unsigned long mask;
225 
226 	mask = (psw.mask & PSW_MASK_EA) ? -1UL :
227 	       (psw.mask & PSW_MASK_BA) ? (1UL << 31) - 1 :
228 					  (1UL << 24) - 1;
229 	return (psw.addr - ilc) & mask;
230 #endif
231 }
232 
233 /*
234  * Function to drop a processor into disabled wait state
235  */
236 static inline void __noreturn disabled_wait(unsigned long code)
237 {
238         unsigned long ctl_buf;
239         psw_t dw_psw;
240 
241 	dw_psw.mask = PSW_MASK_BASE | PSW_MASK_WAIT | PSW_MASK_BA | PSW_MASK_EA;
242         dw_psw.addr = code;
243         /*
244          * Store status and then load disabled wait psw,
245          * the processor is dead afterwards
246          */
247 #ifndef CONFIG_64BIT
248 	asm volatile(
249 		"	stctl	0,0,0(%2)\n"
250 		"	ni	0(%2),0xef\n"	/* switch off protection */
251 		"	lctl	0,0,0(%2)\n"
252 		"	stpt	0xd8\n"		/* store timer */
253 		"	stckc	0xe0\n"		/* store clock comparator */
254 		"	stpx	0x108\n"	/* store prefix register */
255 		"	stam	0,15,0x120\n"	/* store access registers */
256 		"	std	0,0x160\n"	/* store f0 */
257 		"	std	2,0x168\n"	/* store f2 */
258 		"	std	4,0x170\n"	/* store f4 */
259 		"	std	6,0x178\n"	/* store f6 */
260 		"	stm	0,15,0x180\n"	/* store general registers */
261 		"	stctl	0,15,0x1c0\n"	/* store control registers */
262 		"	oi	0x1c0,0x10\n"	/* fake protection bit */
263 		"	lpsw	0(%1)"
264 		: "=m" (ctl_buf)
265 		: "a" (&dw_psw), "a" (&ctl_buf), "m" (dw_psw) : "cc");
266 #else /* CONFIG_64BIT */
267 	asm volatile(
268 		"	stctg	0,0,0(%2)\n"
269 		"	ni	4(%2),0xef\n"	/* switch off protection */
270 		"	lctlg	0,0,0(%2)\n"
271 		"	lghi	1,0x1000\n"
272 		"	stpt	0x328(1)\n"	/* store timer */
273 		"	stckc	0x330(1)\n"	/* store clock comparator */
274 		"	stpx	0x318(1)\n"	/* store prefix register */
275 		"	stam	0,15,0x340(1)\n"/* store access registers */
276 		"	stfpc	0x31c(1)\n"	/* store fpu control */
277 		"	std	0,0x200(1)\n"	/* store f0 */
278 		"	std	1,0x208(1)\n"	/* store f1 */
279 		"	std	2,0x210(1)\n"	/* store f2 */
280 		"	std	3,0x218(1)\n"	/* store f3 */
281 		"	std	4,0x220(1)\n"	/* store f4 */
282 		"	std	5,0x228(1)\n"	/* store f5 */
283 		"	std	6,0x230(1)\n"	/* store f6 */
284 		"	std	7,0x238(1)\n"	/* store f7 */
285 		"	std	8,0x240(1)\n"	/* store f8 */
286 		"	std	9,0x248(1)\n"	/* store f9 */
287 		"	std	10,0x250(1)\n"	/* store f10 */
288 		"	std	11,0x258(1)\n"	/* store f11 */
289 		"	std	12,0x260(1)\n"	/* store f12 */
290 		"	std	13,0x268(1)\n"	/* store f13 */
291 		"	std	14,0x270(1)\n"	/* store f14 */
292 		"	std	15,0x278(1)\n"	/* store f15 */
293 		"	stmg	0,15,0x280(1)\n"/* store general registers */
294 		"	stctg	0,15,0x380(1)\n"/* store control registers */
295 		"	oi	0x384(1),0x10\n"/* fake protection bit */
296 		"	lpswe	0(%1)"
297 		: "=m" (ctl_buf)
298 		: "a" (&dw_psw), "a" (&ctl_buf), "m" (dw_psw) : "cc", "0", "1");
299 #endif /* CONFIG_64BIT */
300 	while (1);
301 }
302 
303 /*
304  * Use to set psw mask except for the first byte which
305  * won't be changed by this function.
306  */
307 static inline void
308 __set_psw_mask(unsigned long mask)
309 {
310 	__load_psw_mask(mask | (arch_local_save_flags() & ~(-1UL >> 8)));
311 }
312 
313 #define local_mcck_enable() \
314 	__set_psw_mask(psw_kernel_bits | PSW_MASK_DAT | PSW_MASK_MCHECK)
315 #define local_mcck_disable() \
316 	__set_psw_mask(psw_kernel_bits | PSW_MASK_DAT)
317 
318 /*
319  * Basic Machine Check/Program Check Handler.
320  */
321 
322 extern void s390_base_mcck_handler(void);
323 extern void s390_base_pgm_handler(void);
324 extern void s390_base_ext_handler(void);
325 
326 extern void (*s390_base_mcck_handler_fn)(void);
327 extern void (*s390_base_pgm_handler_fn)(void);
328 extern void (*s390_base_ext_handler_fn)(void);
329 
330 #define ARCH_LOW_ADDRESS_LIMIT	0x7fffffffUL
331 
332 /*
333  * Helper macro for exception table entries
334  */
335 #ifndef CONFIG_64BIT
336 #define EX_TABLE(_fault,_target)			\
337 	".section __ex_table,\"a\"\n"			\
338 	"	.align 4\n"				\
339 	"	.long  " #_fault "," #_target "\n"	\
340 	".previous\n"
341 #else
342 #define EX_TABLE(_fault,_target)			\
343 	".section __ex_table,\"a\"\n"			\
344 	"	.align 8\n"				\
345 	"	.quad  " #_fault "," #_target "\n"	\
346 	".previous\n"
347 #endif
348 
349 extern int memcpy_real(void *, void *, size_t);
350 extern void memcpy_absolute(void *, void *, size_t);
351 
352 #define mem_assign_absolute(dest, val) {			\
353 	__typeof__(dest) __tmp = (val);				\
354 								\
355 	BUILD_BUG_ON(sizeof(__tmp) != sizeof(val));		\
356 	memcpy_absolute(&(dest), &__tmp, sizeof(__tmp));	\
357 }
358 
359 #endif                                 /* __ASM_S390_PROCESSOR_H           */
360