xref: /openbmc/linux/arch/s390/include/asm/processor.h (revision 93d90ad7)
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 #define CIF_MCCK_PENDING	0	/* machine check handling is pending */
15 #define CIF_ASCE		1	/* user asce needs fixup / uaccess */
16 #define CIF_NOHZ_DELAY		2	/* delay HZ disable for a tick */
17 
18 #define _CIF_MCCK_PENDING	(1<<CIF_MCCK_PENDING)
19 #define _CIF_ASCE		(1<<CIF_ASCE)
20 #define _CIF_NOHZ_DELAY		(1<<CIF_NOHZ_DELAY)
21 
22 
23 #ifndef __ASSEMBLY__
24 
25 #include <linux/linkage.h>
26 #include <linux/irqflags.h>
27 #include <asm/cpu.h>
28 #include <asm/page.h>
29 #include <asm/ptrace.h>
30 #include <asm/setup.h>
31 #include <asm/runtime_instr.h>
32 
33 static inline void set_cpu_flag(int flag)
34 {
35 	S390_lowcore.cpu_flags |= (1U << flag);
36 }
37 
38 static inline void clear_cpu_flag(int flag)
39 {
40 	S390_lowcore.cpu_flags &= ~(1U << flag);
41 }
42 
43 static inline int test_cpu_flag(int flag)
44 {
45 	return !!(S390_lowcore.cpu_flags & (1U << flag));
46 }
47 
48 #define arch_needs_cpu() test_cpu_flag(CIF_NOHZ_DELAY)
49 
50 /*
51  * Default implementation of macro that returns current
52  * instruction pointer ("program counter").
53  */
54 #define current_text_addr() ({ void *pc; asm("basr %0,0" : "=a" (pc)); pc; })
55 
56 static inline void get_cpu_id(struct cpuid *ptr)
57 {
58 	asm volatile("stidp %0" : "=Q" (*ptr));
59 }
60 
61 extern void s390_adjust_jiffies(void);
62 extern const struct seq_operations cpuinfo_op;
63 extern int sysctl_ieee_emulation_warnings;
64 extern void execve_tail(void);
65 
66 /*
67  * User space process size: 2GB for 31 bit, 4TB or 8PT for 64 bit.
68  */
69 #ifndef CONFIG_64BIT
70 
71 #define TASK_SIZE		(1UL << 31)
72 #define TASK_MAX_SIZE		(1UL << 31)
73 #define TASK_UNMAPPED_BASE	(1UL << 30)
74 
75 #else /* CONFIG_64BIT */
76 
77 #define TASK_SIZE_OF(tsk)	((tsk)->mm->context.asce_limit)
78 #define TASK_UNMAPPED_BASE	(test_thread_flag(TIF_31BIT) ? \
79 					(1UL << 30) : (1UL << 41))
80 #define TASK_SIZE		TASK_SIZE_OF(current)
81 #define TASK_MAX_SIZE		(1UL << 53)
82 
83 #endif /* CONFIG_64BIT */
84 
85 #ifndef CONFIG_64BIT
86 #define STACK_TOP		(1UL << 31)
87 #define STACK_TOP_MAX		(1UL << 31)
88 #else /* CONFIG_64BIT */
89 #define STACK_TOP		(1UL << (test_thread_flag(TIF_31BIT) ? 31:42))
90 #define STACK_TOP_MAX		(1UL << 42)
91 #endif /* CONFIG_64BIT */
92 
93 #define HAVE_ARCH_PICK_MMAP_LAYOUT
94 
95 typedef struct {
96         __u32 ar4;
97 } mm_segment_t;
98 
99 /*
100  * Thread structure
101  */
102 struct thread_struct {
103 	s390_fp_regs fp_regs;
104 	unsigned int  acrs[NUM_ACRS];
105         unsigned long ksp;              /* kernel stack pointer             */
106 	mm_segment_t mm_segment;
107 	unsigned long gmap_addr;	/* address of last gmap fault. */
108 	unsigned int gmap_pfault;	/* signal of a pending guest pfault */
109 	struct per_regs per_user;	/* User specified PER registers */
110 	struct per_event per_event;	/* Cause of the last PER trap */
111 	unsigned long per_flags;	/* Flags to control debug behavior */
112         /* pfault_wait is used to block the process on a pfault event */
113 	unsigned long pfault_wait;
114 	struct list_head list;
115 	/* cpu runtime instrumentation */
116 	struct runtime_instr_cb *ri_cb;
117 	int ri_signum;
118 #ifdef CONFIG_64BIT
119 	unsigned char trap_tdb[256];	/* Transaction abort diagnose block */
120 	__vector128 *vxrs;		/* Vector register save area */
121 #endif
122 };
123 
124 /* Flag to disable transactions. */
125 #define PER_FLAG_NO_TE			1UL
126 /* Flag to enable random transaction aborts. */
127 #define PER_FLAG_TE_ABORT_RAND		2UL
128 /* Flag to specify random transaction abort mode:
129  * - abort each transaction at a random instruction before TEND if set.
130  * - abort random transactions at a random instruction if cleared.
131  */
132 #define PER_FLAG_TE_ABORT_RAND_TEND	4UL
133 
134 typedef struct thread_struct thread_struct;
135 
136 /*
137  * Stack layout of a C stack frame.
138  */
139 #ifndef __PACK_STACK
140 struct stack_frame {
141 	unsigned long back_chain;
142 	unsigned long empty1[5];
143 	unsigned long gprs[10];
144 	unsigned int  empty2[8];
145 };
146 #else
147 struct stack_frame {
148 	unsigned long empty1[5];
149 	unsigned int  empty2[8];
150 	unsigned long gprs[10];
151 	unsigned long back_chain;
152 };
153 #endif
154 
155 #define ARCH_MIN_TASKALIGN	8
156 
157 #define INIT_THREAD {							\
158 	.ksp = sizeof(init_stack) + (unsigned long) &init_stack,	\
159 }
160 
161 /*
162  * Do necessary setup to start up a new thread.
163  */
164 #define start_thread(regs, new_psw, new_stackp) do {			\
165 	regs->psw.mask	= PSW_USER_BITS | PSW_MASK_EA | PSW_MASK_BA;	\
166 	regs->psw.addr	= new_psw | PSW_ADDR_AMODE;			\
167 	regs->gprs[15]	= new_stackp;					\
168 	execve_tail();							\
169 } while (0)
170 
171 #define start_thread31(regs, new_psw, new_stackp) do {			\
172 	regs->psw.mask	= PSW_USER_BITS | PSW_MASK_BA;			\
173 	regs->psw.addr	= new_psw | PSW_ADDR_AMODE;			\
174 	regs->gprs[15]	= new_stackp;					\
175 	crst_table_downgrade(current->mm, 1UL << 31);			\
176 	execve_tail();							\
177 } while (0)
178 
179 /* Forward declaration, a strange C thing */
180 struct task_struct;
181 struct mm_struct;
182 struct seq_file;
183 
184 #ifdef CONFIG_64BIT
185 extern void show_cacheinfo(struct seq_file *m);
186 #else
187 static inline void show_cacheinfo(struct seq_file *m) { }
188 #endif
189 
190 /* Free all resources held by a thread. */
191 extern void release_thread(struct task_struct *);
192 
193 /*
194  * Return saved PC of a blocked thread.
195  */
196 extern unsigned long thread_saved_pc(struct task_struct *t);
197 
198 unsigned long get_wchan(struct task_struct *p);
199 #define task_pt_regs(tsk) ((struct pt_regs *) \
200         (task_stack_page(tsk) + THREAD_SIZE) - 1)
201 #define KSTK_EIP(tsk)	(task_pt_regs(tsk)->psw.addr)
202 #define KSTK_ESP(tsk)	(task_pt_regs(tsk)->gprs[15])
203 
204 /* Has task runtime instrumentation enabled ? */
205 #define is_ri_task(tsk) (!!(tsk)->thread.ri_cb)
206 
207 static inline unsigned short stap(void)
208 {
209 	unsigned short cpu_address;
210 
211 	asm volatile("stap %0" : "=m" (cpu_address));
212 	return cpu_address;
213 }
214 
215 /*
216  * Give up the time slice of the virtual PU.
217  */
218 static inline void cpu_relax(void)
219 {
220 	barrier();
221 }
222 
223 #define cpu_relax_lowlatency()  barrier()
224 
225 static inline void psw_set_key(unsigned int key)
226 {
227 	asm volatile("spka 0(%0)" : : "d" (key));
228 }
229 
230 /*
231  * Set PSW to specified value.
232  */
233 static inline void __load_psw(psw_t psw)
234 {
235 #ifndef CONFIG_64BIT
236 	asm volatile("lpsw  %0" : : "Q" (psw) : "cc");
237 #else
238 	asm volatile("lpswe %0" : : "Q" (psw) : "cc");
239 #endif
240 }
241 
242 /*
243  * Set PSW mask to specified value, while leaving the
244  * PSW addr pointing to the next instruction.
245  */
246 static inline void __load_psw_mask (unsigned long mask)
247 {
248 	unsigned long addr;
249 	psw_t psw;
250 
251 	psw.mask = mask;
252 
253 #ifndef CONFIG_64BIT
254 	asm volatile(
255 		"	basr	%0,0\n"
256 		"0:	ahi	%0,1f-0b\n"
257 		"	st	%0,%O1+4(%R1)\n"
258 		"	lpsw	%1\n"
259 		"1:"
260 		: "=&d" (addr), "=Q" (psw) : "Q" (psw) : "memory", "cc");
261 #else /* CONFIG_64BIT */
262 	asm volatile(
263 		"	larl	%0,1f\n"
264 		"	stg	%0,%O1+8(%R1)\n"
265 		"	lpswe	%1\n"
266 		"1:"
267 		: "=&d" (addr), "=Q" (psw) : "Q" (psw) : "memory", "cc");
268 #endif /* CONFIG_64BIT */
269 }
270 
271 /*
272  * Rewind PSW instruction address by specified number of bytes.
273  */
274 static inline unsigned long __rewind_psw(psw_t psw, unsigned long ilc)
275 {
276 #ifndef CONFIG_64BIT
277 	if (psw.addr & PSW_ADDR_AMODE)
278 		/* 31 bit mode */
279 		return (psw.addr - ilc) | PSW_ADDR_AMODE;
280 	/* 24 bit mode */
281 	return (psw.addr - ilc) & ((1UL << 24) - 1);
282 #else
283 	unsigned long mask;
284 
285 	mask = (psw.mask & PSW_MASK_EA) ? -1UL :
286 	       (psw.mask & PSW_MASK_BA) ? (1UL << 31) - 1 :
287 					  (1UL << 24) - 1;
288 	return (psw.addr - ilc) & mask;
289 #endif
290 }
291 
292 /*
293  * Function to stop a processor until the next interrupt occurs
294  */
295 void enabled_wait(void);
296 
297 /*
298  * Function to drop a processor into disabled wait state
299  */
300 static inline void __noreturn disabled_wait(unsigned long code)
301 {
302         unsigned long ctl_buf;
303         psw_t dw_psw;
304 
305 	dw_psw.mask = PSW_MASK_BASE | PSW_MASK_WAIT | PSW_MASK_BA | PSW_MASK_EA;
306         dw_psw.addr = code;
307         /*
308          * Store status and then load disabled wait psw,
309          * the processor is dead afterwards
310          */
311 #ifndef CONFIG_64BIT
312 	asm volatile(
313 		"	stctl	0,0,0(%2)\n"
314 		"	ni	0(%2),0xef\n"	/* switch off protection */
315 		"	lctl	0,0,0(%2)\n"
316 		"	stpt	0xd8\n"		/* store timer */
317 		"	stckc	0xe0\n"		/* store clock comparator */
318 		"	stpx	0x108\n"	/* store prefix register */
319 		"	stam	0,15,0x120\n"	/* store access registers */
320 		"	std	0,0x160\n"	/* store f0 */
321 		"	std	2,0x168\n"	/* store f2 */
322 		"	std	4,0x170\n"	/* store f4 */
323 		"	std	6,0x178\n"	/* store f6 */
324 		"	stm	0,15,0x180\n"	/* store general registers */
325 		"	stctl	0,15,0x1c0\n"	/* store control registers */
326 		"	oi	0x1c0,0x10\n"	/* fake protection bit */
327 		"	lpsw	0(%1)"
328 		: "=m" (ctl_buf)
329 		: "a" (&dw_psw), "a" (&ctl_buf), "m" (dw_psw) : "cc");
330 #else /* CONFIG_64BIT */
331 	asm volatile(
332 		"	stctg	0,0,0(%2)\n"
333 		"	ni	4(%2),0xef\n"	/* switch off protection */
334 		"	lctlg	0,0,0(%2)\n"
335 		"	lghi	1,0x1000\n"
336 		"	stpt	0x328(1)\n"	/* store timer */
337 		"	stckc	0x330(1)\n"	/* store clock comparator */
338 		"	stpx	0x318(1)\n"	/* store prefix register */
339 		"	stam	0,15,0x340(1)\n"/* store access registers */
340 		"	stfpc	0x31c(1)\n"	/* store fpu control */
341 		"	std	0,0x200(1)\n"	/* store f0 */
342 		"	std	1,0x208(1)\n"	/* store f1 */
343 		"	std	2,0x210(1)\n"	/* store f2 */
344 		"	std	3,0x218(1)\n"	/* store f3 */
345 		"	std	4,0x220(1)\n"	/* store f4 */
346 		"	std	5,0x228(1)\n"	/* store f5 */
347 		"	std	6,0x230(1)\n"	/* store f6 */
348 		"	std	7,0x238(1)\n"	/* store f7 */
349 		"	std	8,0x240(1)\n"	/* store f8 */
350 		"	std	9,0x248(1)\n"	/* store f9 */
351 		"	std	10,0x250(1)\n"	/* store f10 */
352 		"	std	11,0x258(1)\n"	/* store f11 */
353 		"	std	12,0x260(1)\n"	/* store f12 */
354 		"	std	13,0x268(1)\n"	/* store f13 */
355 		"	std	14,0x270(1)\n"	/* store f14 */
356 		"	std	15,0x278(1)\n"	/* store f15 */
357 		"	stmg	0,15,0x280(1)\n"/* store general registers */
358 		"	stctg	0,15,0x380(1)\n"/* store control registers */
359 		"	oi	0x384(1),0x10\n"/* fake protection bit */
360 		"	lpswe	0(%1)"
361 		: "=m" (ctl_buf)
362 		: "a" (&dw_psw), "a" (&ctl_buf), "m" (dw_psw) : "cc", "0", "1");
363 #endif /* CONFIG_64BIT */
364 	while (1);
365 }
366 
367 /*
368  * Use to set psw mask except for the first byte which
369  * won't be changed by this function.
370  */
371 static inline void
372 __set_psw_mask(unsigned long mask)
373 {
374 	__load_psw_mask(mask | (arch_local_save_flags() & ~(-1UL >> 8)));
375 }
376 
377 #define local_mcck_enable() \
378 	__set_psw_mask(PSW_KERNEL_BITS | PSW_MASK_DAT | PSW_MASK_MCHECK)
379 #define local_mcck_disable() \
380 	__set_psw_mask(PSW_KERNEL_BITS | PSW_MASK_DAT)
381 
382 /*
383  * Basic Machine Check/Program Check Handler.
384  */
385 
386 extern void s390_base_mcck_handler(void);
387 extern void s390_base_pgm_handler(void);
388 extern void s390_base_ext_handler(void);
389 
390 extern void (*s390_base_mcck_handler_fn)(void);
391 extern void (*s390_base_pgm_handler_fn)(void);
392 extern void (*s390_base_ext_handler_fn)(void);
393 
394 #define ARCH_LOW_ADDRESS_LIMIT	0x7fffffffUL
395 
396 extern int memcpy_real(void *, void *, size_t);
397 extern void memcpy_absolute(void *, void *, size_t);
398 
399 #define mem_assign_absolute(dest, val) {			\
400 	__typeof__(dest) __tmp = (val);				\
401 								\
402 	BUILD_BUG_ON(sizeof(__tmp) != sizeof(val));		\
403 	memcpy_absolute(&(dest), &__tmp, sizeof(__tmp));	\
404 }
405 
406 /*
407  * Helper macro for exception table entries
408  */
409 #define EX_TABLE(_fault, _target)	\
410 	".section __ex_table,\"a\"\n"	\
411 	".align	4\n"			\
412 	".long	(" #_fault ") - .\n"	\
413 	".long	(" #_target ") - .\n"	\
414 	".previous\n"
415 
416 #else /* __ASSEMBLY__ */
417 
418 #define EX_TABLE(_fault, _target)	\
419 	.section __ex_table,"a"	;	\
420 	.align	4 ;			\
421 	.long	(_fault) - . ;		\
422 	.long	(_target) - . ;		\
423 	.previous
424 
425 #endif /* __ASSEMBLY__ */
426 
427 #endif /* __ASM_S390_PROCESSOR_H */
428