xref: /openbmc/linux/arch/s390/include/asm/processor.h (revision 9d749629)
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 #ifndef __ASSEMBLY__
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 #include <asm/runtime_instr.h>
23 
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 const struct seq_operations cpuinfo_op;
37 extern int sysctl_ieee_emulation_warnings;
38 extern void execve_tail(void);
39 
40 /*
41  * User space process size: 2GB for 31 bit, 4TB or 8PT for 64 bit.
42  */
43 #ifndef CONFIG_64BIT
44 
45 #define TASK_SIZE		(1UL << 31)
46 #define TASK_UNMAPPED_BASE	(1UL << 30)
47 
48 #else /* CONFIG_64BIT */
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 /* CONFIG_64BIT */
56 
57 #ifndef CONFIG_64BIT
58 #define STACK_TOP		(1UL << 31)
59 #define STACK_TOP_MAX		(1UL << 31)
60 #else /* CONFIG_64BIT */
61 #define STACK_TOP		(1UL << (test_thread_flag(TIF_31BIT) ? 31:42))
62 #define STACK_TOP_MAX		(1UL << 42)
63 #endif /* CONFIG_64BIT */
64 
65 #define HAVE_ARCH_PICK_MMAP_LAYOUT
66 
67 typedef struct {
68         __u32 ar4;
69 } mm_segment_t;
70 
71 /*
72  * Thread structure
73  */
74 struct thread_struct {
75 	s390_fp_regs fp_regs;
76 	unsigned int  acrs[NUM_ACRS];
77         unsigned long ksp;              /* kernel stack pointer             */
78 	mm_segment_t mm_segment;
79 	unsigned long gmap_addr;	/* address of last gmap fault. */
80 	struct per_regs per_user;	/* User specified PER registers */
81 	struct per_event per_event;	/* Cause of the last PER trap */
82 	unsigned long per_flags;	/* Flags to control debug behavior */
83         /* pfault_wait is used to block the process on a pfault event */
84 	unsigned long pfault_wait;
85 	struct list_head list;
86 	/* cpu runtime instrumentation */
87 	struct runtime_instr_cb *ri_cb;
88 	int ri_signum;
89 #ifdef CONFIG_64BIT
90 	unsigned char trap_tdb[256];	/* Transaction abort diagnose block */
91 #endif
92 };
93 
94 #define PER_FLAG_NO_TE		1UL	/* Flag to disable transactions. */
95 
96 typedef struct thread_struct thread_struct;
97 
98 /*
99  * Stack layout of a C stack frame.
100  */
101 #ifndef __PACK_STACK
102 struct stack_frame {
103 	unsigned long back_chain;
104 	unsigned long empty1[5];
105 	unsigned long gprs[10];
106 	unsigned int  empty2[8];
107 };
108 #else
109 struct stack_frame {
110 	unsigned long empty1[5];
111 	unsigned int  empty2[8];
112 	unsigned long gprs[10];
113 	unsigned long back_chain;
114 };
115 #endif
116 
117 #define ARCH_MIN_TASKALIGN	8
118 
119 #define INIT_THREAD {							\
120 	.ksp = sizeof(init_stack) + (unsigned long) &init_stack,	\
121 }
122 
123 /*
124  * Do necessary setup to start up a new thread.
125  */
126 #define start_thread(regs, new_psw, new_stackp) do {			\
127 	regs->psw.mask	= psw_user_bits | PSW_MASK_EA | PSW_MASK_BA;	\
128 	regs->psw.addr	= new_psw | PSW_ADDR_AMODE;			\
129 	regs->gprs[15]	= new_stackp;					\
130 	execve_tail();							\
131 } while (0)
132 
133 #define start_thread31(regs, new_psw, new_stackp) do {			\
134 	regs->psw.mask	= psw_user_bits | PSW_MASK_BA;			\
135 	regs->psw.addr	= new_psw | PSW_ADDR_AMODE;			\
136 	regs->gprs[15]	= new_stackp;					\
137 	__tlb_flush_mm(current->mm);					\
138 	crst_table_downgrade(current->mm, 1UL << 31);			\
139 	update_mm(current->mm, current);				\
140 	execve_tail();							\
141 } while (0)
142 
143 /* Forward declaration, a strange C thing */
144 struct task_struct;
145 struct mm_struct;
146 struct seq_file;
147 
148 #ifdef CONFIG_64BIT
149 extern void show_cacheinfo(struct seq_file *m);
150 #else
151 static inline void show_cacheinfo(struct seq_file *m) { }
152 #endif
153 
154 /* Free all resources held by a thread. */
155 extern void release_thread(struct task_struct *);
156 
157 /*
158  * Return saved PC of a blocked thread.
159  */
160 extern unsigned long thread_saved_pc(struct task_struct *t);
161 
162 extern void show_code(struct pt_regs *regs);
163 extern void print_fn_code(unsigned char *code, unsigned long len);
164 extern int insn_to_mnemonic(unsigned char *instruction, char buf[8]);
165 
166 unsigned long get_wchan(struct task_struct *p);
167 #define task_pt_regs(tsk) ((struct pt_regs *) \
168         (task_stack_page(tsk) + THREAD_SIZE) - 1)
169 #define KSTK_EIP(tsk)	(task_pt_regs(tsk)->psw.addr)
170 #define KSTK_ESP(tsk)	(task_pt_regs(tsk)->gprs[15])
171 
172 static inline unsigned short stap(void)
173 {
174 	unsigned short cpu_address;
175 
176 	asm volatile("stap %0" : "=m" (cpu_address));
177 	return cpu_address;
178 }
179 
180 /*
181  * Give up the time slice of the virtual PU.
182  */
183 static inline void cpu_relax(void)
184 {
185 	if (MACHINE_HAS_DIAG44)
186 		asm volatile("diag 0,0,68");
187 	barrier();
188 }
189 
190 static inline void psw_set_key(unsigned int key)
191 {
192 	asm volatile("spka 0(%0)" : : "d" (key));
193 }
194 
195 /*
196  * Set PSW to specified value.
197  */
198 static inline void __load_psw(psw_t psw)
199 {
200 #ifndef CONFIG_64BIT
201 	asm volatile("lpsw  %0" : : "Q" (psw) : "cc");
202 #else
203 	asm volatile("lpswe %0" : : "Q" (psw) : "cc");
204 #endif
205 }
206 
207 /*
208  * Set PSW mask to specified value, while leaving the
209  * PSW addr pointing to the next instruction.
210  */
211 static inline void __load_psw_mask (unsigned long mask)
212 {
213 	unsigned long addr;
214 	psw_t psw;
215 
216 	psw.mask = mask;
217 
218 #ifndef CONFIG_64BIT
219 	asm volatile(
220 		"	basr	%0,0\n"
221 		"0:	ahi	%0,1f-0b\n"
222 		"	st	%0,%O1+4(%R1)\n"
223 		"	lpsw	%1\n"
224 		"1:"
225 		: "=&d" (addr), "=Q" (psw) : "Q" (psw) : "memory", "cc");
226 #else /* CONFIG_64BIT */
227 	asm volatile(
228 		"	larl	%0,1f\n"
229 		"	stg	%0,%O1+8(%R1)\n"
230 		"	lpswe	%1\n"
231 		"1:"
232 		: "=&d" (addr), "=Q" (psw) : "Q" (psw) : "memory", "cc");
233 #endif /* CONFIG_64BIT */
234 }
235 
236 /*
237  * Rewind PSW instruction address by specified number of bytes.
238  */
239 static inline unsigned long __rewind_psw(psw_t psw, unsigned long ilc)
240 {
241 #ifndef CONFIG_64BIT
242 	if (psw.addr & PSW_ADDR_AMODE)
243 		/* 31 bit mode */
244 		return (psw.addr - ilc) | PSW_ADDR_AMODE;
245 	/* 24 bit mode */
246 	return (psw.addr - ilc) & ((1UL << 24) - 1);
247 #else
248 	unsigned long mask;
249 
250 	mask = (psw.mask & PSW_MASK_EA) ? -1UL :
251 	       (psw.mask & PSW_MASK_BA) ? (1UL << 31) - 1 :
252 					  (1UL << 24) - 1;
253 	return (psw.addr - ilc) & mask;
254 #endif
255 }
256 
257 /*
258  * Function to drop a processor into disabled wait state
259  */
260 static inline void __noreturn disabled_wait(unsigned long code)
261 {
262         unsigned long ctl_buf;
263         psw_t dw_psw;
264 
265 	dw_psw.mask = PSW_MASK_BASE | PSW_MASK_WAIT | PSW_MASK_BA | PSW_MASK_EA;
266         dw_psw.addr = code;
267         /*
268          * Store status and then load disabled wait psw,
269          * the processor is dead afterwards
270          */
271 #ifndef CONFIG_64BIT
272 	asm volatile(
273 		"	stctl	0,0,0(%2)\n"
274 		"	ni	0(%2),0xef\n"	/* switch off protection */
275 		"	lctl	0,0,0(%2)\n"
276 		"	stpt	0xd8\n"		/* store timer */
277 		"	stckc	0xe0\n"		/* store clock comparator */
278 		"	stpx	0x108\n"	/* store prefix register */
279 		"	stam	0,15,0x120\n"	/* store access registers */
280 		"	std	0,0x160\n"	/* store f0 */
281 		"	std	2,0x168\n"	/* store f2 */
282 		"	std	4,0x170\n"	/* store f4 */
283 		"	std	6,0x178\n"	/* store f6 */
284 		"	stm	0,15,0x180\n"	/* store general registers */
285 		"	stctl	0,15,0x1c0\n"	/* store control registers */
286 		"	oi	0x1c0,0x10\n"	/* fake protection bit */
287 		"	lpsw	0(%1)"
288 		: "=m" (ctl_buf)
289 		: "a" (&dw_psw), "a" (&ctl_buf), "m" (dw_psw) : "cc");
290 #else /* CONFIG_64BIT */
291 	asm volatile(
292 		"	stctg	0,0,0(%2)\n"
293 		"	ni	4(%2),0xef\n"	/* switch off protection */
294 		"	lctlg	0,0,0(%2)\n"
295 		"	lghi	1,0x1000\n"
296 		"	stpt	0x328(1)\n"	/* store timer */
297 		"	stckc	0x330(1)\n"	/* store clock comparator */
298 		"	stpx	0x318(1)\n"	/* store prefix register */
299 		"	stam	0,15,0x340(1)\n"/* store access registers */
300 		"	stfpc	0x31c(1)\n"	/* store fpu control */
301 		"	std	0,0x200(1)\n"	/* store f0 */
302 		"	std	1,0x208(1)\n"	/* store f1 */
303 		"	std	2,0x210(1)\n"	/* store f2 */
304 		"	std	3,0x218(1)\n"	/* store f3 */
305 		"	std	4,0x220(1)\n"	/* store f4 */
306 		"	std	5,0x228(1)\n"	/* store f5 */
307 		"	std	6,0x230(1)\n"	/* store f6 */
308 		"	std	7,0x238(1)\n"	/* store f7 */
309 		"	std	8,0x240(1)\n"	/* store f8 */
310 		"	std	9,0x248(1)\n"	/* store f9 */
311 		"	std	10,0x250(1)\n"	/* store f10 */
312 		"	std	11,0x258(1)\n"	/* store f11 */
313 		"	std	12,0x260(1)\n"	/* store f12 */
314 		"	std	13,0x268(1)\n"	/* store f13 */
315 		"	std	14,0x270(1)\n"	/* store f14 */
316 		"	std	15,0x278(1)\n"	/* store f15 */
317 		"	stmg	0,15,0x280(1)\n"/* store general registers */
318 		"	stctg	0,15,0x380(1)\n"/* store control registers */
319 		"	oi	0x384(1),0x10\n"/* fake protection bit */
320 		"	lpswe	0(%1)"
321 		: "=m" (ctl_buf)
322 		: "a" (&dw_psw), "a" (&ctl_buf), "m" (dw_psw) : "cc", "0", "1");
323 #endif /* CONFIG_64BIT */
324 	while (1);
325 }
326 
327 /*
328  * Use to set psw mask except for the first byte which
329  * won't be changed by this function.
330  */
331 static inline void
332 __set_psw_mask(unsigned long mask)
333 {
334 	__load_psw_mask(mask | (arch_local_save_flags() & ~(-1UL >> 8)));
335 }
336 
337 #define local_mcck_enable() \
338 	__set_psw_mask(psw_kernel_bits | PSW_MASK_DAT | PSW_MASK_MCHECK)
339 #define local_mcck_disable() \
340 	__set_psw_mask(psw_kernel_bits | PSW_MASK_DAT)
341 
342 /*
343  * Basic Machine Check/Program Check Handler.
344  */
345 
346 extern void s390_base_mcck_handler(void);
347 extern void s390_base_pgm_handler(void);
348 extern void s390_base_ext_handler(void);
349 
350 extern void (*s390_base_mcck_handler_fn)(void);
351 extern void (*s390_base_pgm_handler_fn)(void);
352 extern void (*s390_base_ext_handler_fn)(void);
353 
354 #define ARCH_LOW_ADDRESS_LIMIT	0x7fffffffUL
355 
356 extern int memcpy_real(void *, void *, size_t);
357 extern void memcpy_absolute(void *, void *, size_t);
358 
359 #define mem_assign_absolute(dest, val) {			\
360 	__typeof__(dest) __tmp = (val);				\
361 								\
362 	BUILD_BUG_ON(sizeof(__tmp) != sizeof(val));		\
363 	memcpy_absolute(&(dest), &__tmp, sizeof(__tmp));	\
364 }
365 
366 /*
367  * Helper macro for exception table entries
368  */
369 #define EX_TABLE(_fault, _target)	\
370 	".section __ex_table,\"a\"\n"	\
371 	".align	4\n"			\
372 	".long	(" #_fault ") - .\n"	\
373 	".long	(" #_target ") - .\n"	\
374 	".previous\n"
375 
376 #else /* __ASSEMBLY__ */
377 
378 #define EX_TABLE(_fault, _target)	\
379 	.section __ex_table,"a"	;	\
380 	.align	4 ;			\
381 	.long	(_fault) - . ;		\
382 	.long	(_target) - . ;		\
383 	.previous
384 
385 #endif /* __ASSEMBLY__ */
386 
387 #endif /* __ASM_S390_PROCESSOR_H */
388