xref: /openbmc/linux/arch/s390/include/asm/processor.h (revision afb46f79)
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_MAX_SIZE		(1UL << 31)
47 #define TASK_UNMAPPED_BASE	(1UL << 30)
48 
49 #else /* CONFIG_64BIT */
50 
51 #define TASK_SIZE_OF(tsk)	((tsk)->mm->context.asce_limit)
52 #define TASK_UNMAPPED_BASE	(test_thread_flag(TIF_31BIT) ? \
53 					(1UL << 30) : (1UL << 41))
54 #define TASK_SIZE		TASK_SIZE_OF(current)
55 #define TASK_MAX_SIZE		(1UL << 53)
56 
57 #endif /* CONFIG_64BIT */
58 
59 #ifndef CONFIG_64BIT
60 #define STACK_TOP		(1UL << 31)
61 #define STACK_TOP_MAX		(1UL << 31)
62 #else /* CONFIG_64BIT */
63 #define STACK_TOP		(1UL << (test_thread_flag(TIF_31BIT) ? 31:42))
64 #define STACK_TOP_MAX		(1UL << 42)
65 #endif /* CONFIG_64BIT */
66 
67 #define HAVE_ARCH_PICK_MMAP_LAYOUT
68 
69 typedef struct {
70         __u32 ar4;
71 } mm_segment_t;
72 
73 /*
74  * Thread structure
75  */
76 struct thread_struct {
77 	s390_fp_regs fp_regs;
78 	unsigned int  acrs[NUM_ACRS];
79         unsigned long ksp;              /* kernel stack pointer             */
80 	mm_segment_t mm_segment;
81 	unsigned long gmap_addr;	/* address of last gmap fault. */
82 	unsigned int gmap_pfault;	/* signal of a pending guest pfault */
83 	struct per_regs per_user;	/* User specified PER registers */
84 	struct per_event per_event;	/* Cause of the last PER trap */
85 	unsigned long per_flags;	/* Flags to control debug behavior */
86         /* pfault_wait is used to block the process on a pfault event */
87 	unsigned long pfault_wait;
88 	struct list_head list;
89 	/* cpu runtime instrumentation */
90 	struct runtime_instr_cb *ri_cb;
91 	int ri_signum;
92 #ifdef CONFIG_64BIT
93 	unsigned char trap_tdb[256];	/* Transaction abort diagnose block */
94 #endif
95 };
96 
97 /* Flag to disable transactions. */
98 #define PER_FLAG_NO_TE			1UL
99 /* Flag to enable random transaction aborts. */
100 #define PER_FLAG_TE_ABORT_RAND		2UL
101 /* Flag to specify random transaction abort mode:
102  * - abort each transaction at a random instruction before TEND if set.
103  * - abort random transactions at a random instruction if cleared.
104  */
105 #define PER_FLAG_TE_ABORT_RAND_TEND	4UL
106 
107 typedef struct thread_struct thread_struct;
108 
109 /*
110  * Stack layout of a C stack frame.
111  */
112 #ifndef __PACK_STACK
113 struct stack_frame {
114 	unsigned long back_chain;
115 	unsigned long empty1[5];
116 	unsigned long gprs[10];
117 	unsigned int  empty2[8];
118 };
119 #else
120 struct stack_frame {
121 	unsigned long empty1[5];
122 	unsigned int  empty2[8];
123 	unsigned long gprs[10];
124 	unsigned long back_chain;
125 };
126 #endif
127 
128 #define ARCH_MIN_TASKALIGN	8
129 
130 #define INIT_THREAD {							\
131 	.ksp = sizeof(init_stack) + (unsigned long) &init_stack,	\
132 }
133 
134 /*
135  * Do necessary setup to start up a new thread.
136  */
137 #define start_thread(regs, new_psw, new_stackp) do {			\
138 	regs->psw.mask	= PSW_USER_BITS | PSW_MASK_EA | PSW_MASK_BA;	\
139 	regs->psw.addr	= new_psw | PSW_ADDR_AMODE;			\
140 	regs->gprs[15]	= new_stackp;					\
141 	execve_tail();							\
142 } while (0)
143 
144 #define start_thread31(regs, new_psw, new_stackp) do {			\
145 	regs->psw.mask	= PSW_USER_BITS | PSW_MASK_BA;			\
146 	regs->psw.addr	= new_psw | PSW_ADDR_AMODE;			\
147 	regs->gprs[15]	= new_stackp;					\
148 	crst_table_downgrade(current->mm, 1UL << 31);			\
149 	execve_tail();							\
150 } while (0)
151 
152 /* Forward declaration, a strange C thing */
153 struct task_struct;
154 struct mm_struct;
155 struct seq_file;
156 
157 #ifdef CONFIG_64BIT
158 extern void show_cacheinfo(struct seq_file *m);
159 #else
160 static inline void show_cacheinfo(struct seq_file *m) { }
161 #endif
162 
163 /* Free all resources held by a thread. */
164 extern void release_thread(struct task_struct *);
165 
166 /*
167  * Return saved PC of a blocked thread.
168  */
169 extern unsigned long thread_saved_pc(struct task_struct *t);
170 
171 unsigned long get_wchan(struct task_struct *p);
172 #define task_pt_regs(tsk) ((struct pt_regs *) \
173         (task_stack_page(tsk) + THREAD_SIZE) - 1)
174 #define KSTK_EIP(tsk)	(task_pt_regs(tsk)->psw.addr)
175 #define KSTK_ESP(tsk)	(task_pt_regs(tsk)->gprs[15])
176 
177 /* Has task runtime instrumentation enabled ? */
178 #define is_ri_task(tsk) (!!(tsk)->thread.ri_cb)
179 
180 static inline unsigned short stap(void)
181 {
182 	unsigned short cpu_address;
183 
184 	asm volatile("stap %0" : "=m" (cpu_address));
185 	return cpu_address;
186 }
187 
188 /*
189  * Give up the time slice of the virtual PU.
190  */
191 static inline void cpu_relax(void)
192 {
193 	if (MACHINE_HAS_DIAG44)
194 		asm volatile("diag 0,0,68");
195 	barrier();
196 }
197 
198 #define arch_mutex_cpu_relax()  barrier()
199 
200 static inline void psw_set_key(unsigned int key)
201 {
202 	asm volatile("spka 0(%0)" : : "d" (key));
203 }
204 
205 /*
206  * Set PSW to specified value.
207  */
208 static inline void __load_psw(psw_t psw)
209 {
210 #ifndef CONFIG_64BIT
211 	asm volatile("lpsw  %0" : : "Q" (psw) : "cc");
212 #else
213 	asm volatile("lpswe %0" : : "Q" (psw) : "cc");
214 #endif
215 }
216 
217 /*
218  * Set PSW mask to specified value, while leaving the
219  * PSW addr pointing to the next instruction.
220  */
221 static inline void __load_psw_mask (unsigned long mask)
222 {
223 	unsigned long addr;
224 	psw_t psw;
225 
226 	psw.mask = mask;
227 
228 #ifndef CONFIG_64BIT
229 	asm volatile(
230 		"	basr	%0,0\n"
231 		"0:	ahi	%0,1f-0b\n"
232 		"	st	%0,%O1+4(%R1)\n"
233 		"	lpsw	%1\n"
234 		"1:"
235 		: "=&d" (addr), "=Q" (psw) : "Q" (psw) : "memory", "cc");
236 #else /* CONFIG_64BIT */
237 	asm volatile(
238 		"	larl	%0,1f\n"
239 		"	stg	%0,%O1+8(%R1)\n"
240 		"	lpswe	%1\n"
241 		"1:"
242 		: "=&d" (addr), "=Q" (psw) : "Q" (psw) : "memory", "cc");
243 #endif /* CONFIG_64BIT */
244 }
245 
246 /*
247  * Rewind PSW instruction address by specified number of bytes.
248  */
249 static inline unsigned long __rewind_psw(psw_t psw, unsigned long ilc)
250 {
251 #ifndef CONFIG_64BIT
252 	if (psw.addr & PSW_ADDR_AMODE)
253 		/* 31 bit mode */
254 		return (psw.addr - ilc) | PSW_ADDR_AMODE;
255 	/* 24 bit mode */
256 	return (psw.addr - ilc) & ((1UL << 24) - 1);
257 #else
258 	unsigned long mask;
259 
260 	mask = (psw.mask & PSW_MASK_EA) ? -1UL :
261 	       (psw.mask & PSW_MASK_BA) ? (1UL << 31) - 1 :
262 					  (1UL << 24) - 1;
263 	return (psw.addr - ilc) & mask;
264 #endif
265 }
266 
267 /*
268  * Function to drop a processor into disabled wait state
269  */
270 static inline void __noreturn disabled_wait(unsigned long code)
271 {
272         unsigned long ctl_buf;
273         psw_t dw_psw;
274 
275 	dw_psw.mask = PSW_MASK_BASE | PSW_MASK_WAIT | PSW_MASK_BA | PSW_MASK_EA;
276         dw_psw.addr = code;
277         /*
278          * Store status and then load disabled wait psw,
279          * the processor is dead afterwards
280          */
281 #ifndef CONFIG_64BIT
282 	asm volatile(
283 		"	stctl	0,0,0(%2)\n"
284 		"	ni	0(%2),0xef\n"	/* switch off protection */
285 		"	lctl	0,0,0(%2)\n"
286 		"	stpt	0xd8\n"		/* store timer */
287 		"	stckc	0xe0\n"		/* store clock comparator */
288 		"	stpx	0x108\n"	/* store prefix register */
289 		"	stam	0,15,0x120\n"	/* store access registers */
290 		"	std	0,0x160\n"	/* store f0 */
291 		"	std	2,0x168\n"	/* store f2 */
292 		"	std	4,0x170\n"	/* store f4 */
293 		"	std	6,0x178\n"	/* store f6 */
294 		"	stm	0,15,0x180\n"	/* store general registers */
295 		"	stctl	0,15,0x1c0\n"	/* store control registers */
296 		"	oi	0x1c0,0x10\n"	/* fake protection bit */
297 		"	lpsw	0(%1)"
298 		: "=m" (ctl_buf)
299 		: "a" (&dw_psw), "a" (&ctl_buf), "m" (dw_psw) : "cc");
300 #else /* CONFIG_64BIT */
301 	asm volatile(
302 		"	stctg	0,0,0(%2)\n"
303 		"	ni	4(%2),0xef\n"	/* switch off protection */
304 		"	lctlg	0,0,0(%2)\n"
305 		"	lghi	1,0x1000\n"
306 		"	stpt	0x328(1)\n"	/* store timer */
307 		"	stckc	0x330(1)\n"	/* store clock comparator */
308 		"	stpx	0x318(1)\n"	/* store prefix register */
309 		"	stam	0,15,0x340(1)\n"/* store access registers */
310 		"	stfpc	0x31c(1)\n"	/* store fpu control */
311 		"	std	0,0x200(1)\n"	/* store f0 */
312 		"	std	1,0x208(1)\n"	/* store f1 */
313 		"	std	2,0x210(1)\n"	/* store f2 */
314 		"	std	3,0x218(1)\n"	/* store f3 */
315 		"	std	4,0x220(1)\n"	/* store f4 */
316 		"	std	5,0x228(1)\n"	/* store f5 */
317 		"	std	6,0x230(1)\n"	/* store f6 */
318 		"	std	7,0x238(1)\n"	/* store f7 */
319 		"	std	8,0x240(1)\n"	/* store f8 */
320 		"	std	9,0x248(1)\n"	/* store f9 */
321 		"	std	10,0x250(1)\n"	/* store f10 */
322 		"	std	11,0x258(1)\n"	/* store f11 */
323 		"	std	12,0x260(1)\n"	/* store f12 */
324 		"	std	13,0x268(1)\n"	/* store f13 */
325 		"	std	14,0x270(1)\n"	/* store f14 */
326 		"	std	15,0x278(1)\n"	/* store f15 */
327 		"	stmg	0,15,0x280(1)\n"/* store general registers */
328 		"	stctg	0,15,0x380(1)\n"/* store control registers */
329 		"	oi	0x384(1),0x10\n"/* fake protection bit */
330 		"	lpswe	0(%1)"
331 		: "=m" (ctl_buf)
332 		: "a" (&dw_psw), "a" (&ctl_buf), "m" (dw_psw) : "cc", "0", "1");
333 #endif /* CONFIG_64BIT */
334 	while (1);
335 }
336 
337 /*
338  * Use to set psw mask except for the first byte which
339  * won't be changed by this function.
340  */
341 static inline void
342 __set_psw_mask(unsigned long mask)
343 {
344 	__load_psw_mask(mask | (arch_local_save_flags() & ~(-1UL >> 8)));
345 }
346 
347 #define local_mcck_enable() \
348 	__set_psw_mask(PSW_KERNEL_BITS | PSW_MASK_DAT | PSW_MASK_MCHECK)
349 #define local_mcck_disable() \
350 	__set_psw_mask(PSW_KERNEL_BITS | PSW_MASK_DAT)
351 
352 /*
353  * Basic Machine Check/Program Check Handler.
354  */
355 
356 extern void s390_base_mcck_handler(void);
357 extern void s390_base_pgm_handler(void);
358 extern void s390_base_ext_handler(void);
359 
360 extern void (*s390_base_mcck_handler_fn)(void);
361 extern void (*s390_base_pgm_handler_fn)(void);
362 extern void (*s390_base_ext_handler_fn)(void);
363 
364 #define ARCH_LOW_ADDRESS_LIMIT	0x7fffffffUL
365 
366 extern int memcpy_real(void *, void *, size_t);
367 extern void memcpy_absolute(void *, void *, size_t);
368 
369 #define mem_assign_absolute(dest, val) {			\
370 	__typeof__(dest) __tmp = (val);				\
371 								\
372 	BUILD_BUG_ON(sizeof(__tmp) != sizeof(val));		\
373 	memcpy_absolute(&(dest), &__tmp, sizeof(__tmp));	\
374 }
375 
376 /*
377  * Helper macro for exception table entries
378  */
379 #define EX_TABLE(_fault, _target)	\
380 	".section __ex_table,\"a\"\n"	\
381 	".align	4\n"			\
382 	".long	(" #_fault ") - .\n"	\
383 	".long	(" #_target ") - .\n"	\
384 	".previous\n"
385 
386 #else /* __ASSEMBLY__ */
387 
388 #define EX_TABLE(_fault, _target)	\
389 	.section __ex_table,"a"	;	\
390 	.align	4 ;			\
391 	.long	(_fault) - . ;		\
392 	.long	(_target) - . ;		\
393 	.previous
394 
395 #endif /* __ASSEMBLY__ */
396 
397 #endif /* __ASM_S390_PROCESSOR_H */
398