xref: /openbmc/linux/arch/s390/include/asm/processor.h (revision 80ecbd24)
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 /* Flag to disable transactions. */
95 #define PER_FLAG_NO_TE			1UL
96 /* Flag to enable random transaction aborts. */
97 #define PER_FLAG_TE_ABORT_RAND		2UL
98 /* Flag to specify random transaction abort mode:
99  * - abort each transaction at a random instruction before TEND if set.
100  * - abort random transactions at a random instruction if cleared.
101  */
102 #define PER_FLAG_TE_ABORT_RAND_TEND	4UL
103 
104 typedef struct thread_struct thread_struct;
105 
106 /*
107  * Stack layout of a C stack frame.
108  */
109 #ifndef __PACK_STACK
110 struct stack_frame {
111 	unsigned long back_chain;
112 	unsigned long empty1[5];
113 	unsigned long gprs[10];
114 	unsigned int  empty2[8];
115 };
116 #else
117 struct stack_frame {
118 	unsigned long empty1[5];
119 	unsigned int  empty2[8];
120 	unsigned long gprs[10];
121 	unsigned long back_chain;
122 };
123 #endif
124 
125 #define ARCH_MIN_TASKALIGN	8
126 
127 #define INIT_THREAD {							\
128 	.ksp = sizeof(init_stack) + (unsigned long) &init_stack,	\
129 }
130 
131 /*
132  * Do necessary setup to start up a new thread.
133  */
134 #define start_thread(regs, new_psw, new_stackp) do {			\
135 	regs->psw.mask	= psw_user_bits | PSW_MASK_EA | PSW_MASK_BA;	\
136 	regs->psw.addr	= new_psw | PSW_ADDR_AMODE;			\
137 	regs->gprs[15]	= new_stackp;					\
138 	execve_tail();							\
139 } while (0)
140 
141 #define start_thread31(regs, new_psw, new_stackp) do {			\
142 	regs->psw.mask	= psw_user_bits | PSW_MASK_BA;			\
143 	regs->psw.addr	= new_psw | PSW_ADDR_AMODE;			\
144 	regs->gprs[15]	= new_stackp;					\
145 	__tlb_flush_mm(current->mm);					\
146 	crst_table_downgrade(current->mm, 1UL << 31);			\
147 	update_mm(current->mm, current);				\
148 	execve_tail();							\
149 } while (0)
150 
151 /* Forward declaration, a strange C thing */
152 struct task_struct;
153 struct mm_struct;
154 struct seq_file;
155 
156 #ifdef CONFIG_64BIT
157 extern void show_cacheinfo(struct seq_file *m);
158 #else
159 static inline void show_cacheinfo(struct seq_file *m) { }
160 #endif
161 
162 /* Free all resources held by a thread. */
163 extern void release_thread(struct task_struct *);
164 
165 /*
166  * Return saved PC of a blocked thread.
167  */
168 extern unsigned long thread_saved_pc(struct task_struct *t);
169 
170 extern void show_code(struct pt_regs *regs);
171 extern void print_fn_code(unsigned char *code, unsigned long len);
172 extern int insn_to_mnemonic(unsigned char *instruction, char *buf,
173 			    unsigned int len);
174 
175 unsigned long get_wchan(struct task_struct *p);
176 #define task_pt_regs(tsk) ((struct pt_regs *) \
177         (task_stack_page(tsk) + THREAD_SIZE) - 1)
178 #define KSTK_EIP(tsk)	(task_pt_regs(tsk)->psw.addr)
179 #define KSTK_ESP(tsk)	(task_pt_regs(tsk)->gprs[15])
180 
181 static inline unsigned short stap(void)
182 {
183 	unsigned short cpu_address;
184 
185 	asm volatile("stap %0" : "=m" (cpu_address));
186 	return cpu_address;
187 }
188 
189 /*
190  * Give up the time slice of the virtual PU.
191  */
192 static inline void cpu_relax(void)
193 {
194 	if (MACHINE_HAS_DIAG44)
195 		asm volatile("diag 0,0,68");
196 	barrier();
197 }
198 
199 static inline void psw_set_key(unsigned int key)
200 {
201 	asm volatile("spka 0(%0)" : : "d" (key));
202 }
203 
204 /*
205  * Set PSW to specified value.
206  */
207 static inline void __load_psw(psw_t psw)
208 {
209 #ifndef CONFIG_64BIT
210 	asm volatile("lpsw  %0" : : "Q" (psw) : "cc");
211 #else
212 	asm volatile("lpswe %0" : : "Q" (psw) : "cc");
213 #endif
214 }
215 
216 /*
217  * Set PSW mask to specified value, while leaving the
218  * PSW addr pointing to the next instruction.
219  */
220 static inline void __load_psw_mask (unsigned long mask)
221 {
222 	unsigned long addr;
223 	psw_t psw;
224 
225 	psw.mask = mask;
226 
227 #ifndef CONFIG_64BIT
228 	asm volatile(
229 		"	basr	%0,0\n"
230 		"0:	ahi	%0,1f-0b\n"
231 		"	st	%0,%O1+4(%R1)\n"
232 		"	lpsw	%1\n"
233 		"1:"
234 		: "=&d" (addr), "=Q" (psw) : "Q" (psw) : "memory", "cc");
235 #else /* CONFIG_64BIT */
236 	asm volatile(
237 		"	larl	%0,1f\n"
238 		"	stg	%0,%O1+8(%R1)\n"
239 		"	lpswe	%1\n"
240 		"1:"
241 		: "=&d" (addr), "=Q" (psw) : "Q" (psw) : "memory", "cc");
242 #endif /* CONFIG_64BIT */
243 }
244 
245 /*
246  * Rewind PSW instruction address by specified number of bytes.
247  */
248 static inline unsigned long __rewind_psw(psw_t psw, unsigned long ilc)
249 {
250 #ifndef CONFIG_64BIT
251 	if (psw.addr & PSW_ADDR_AMODE)
252 		/* 31 bit mode */
253 		return (psw.addr - ilc) | PSW_ADDR_AMODE;
254 	/* 24 bit mode */
255 	return (psw.addr - ilc) & ((1UL << 24) - 1);
256 #else
257 	unsigned long mask;
258 
259 	mask = (psw.mask & PSW_MASK_EA) ? -1UL :
260 	       (psw.mask & PSW_MASK_BA) ? (1UL << 31) - 1 :
261 					  (1UL << 24) - 1;
262 	return (psw.addr - ilc) & mask;
263 #endif
264 }
265 
266 /*
267  * Function to drop a processor into disabled wait state
268  */
269 static inline void __noreturn disabled_wait(unsigned long code)
270 {
271         unsigned long ctl_buf;
272         psw_t dw_psw;
273 
274 	dw_psw.mask = PSW_MASK_BASE | PSW_MASK_WAIT | PSW_MASK_BA | PSW_MASK_EA;
275         dw_psw.addr = code;
276         /*
277          * Store status and then load disabled wait psw,
278          * the processor is dead afterwards
279          */
280 #ifndef CONFIG_64BIT
281 	asm volatile(
282 		"	stctl	0,0,0(%2)\n"
283 		"	ni	0(%2),0xef\n"	/* switch off protection */
284 		"	lctl	0,0,0(%2)\n"
285 		"	stpt	0xd8\n"		/* store timer */
286 		"	stckc	0xe0\n"		/* store clock comparator */
287 		"	stpx	0x108\n"	/* store prefix register */
288 		"	stam	0,15,0x120\n"	/* store access registers */
289 		"	std	0,0x160\n"	/* store f0 */
290 		"	std	2,0x168\n"	/* store f2 */
291 		"	std	4,0x170\n"	/* store f4 */
292 		"	std	6,0x178\n"	/* store f6 */
293 		"	stm	0,15,0x180\n"	/* store general registers */
294 		"	stctl	0,15,0x1c0\n"	/* store control registers */
295 		"	oi	0x1c0,0x10\n"	/* fake protection bit */
296 		"	lpsw	0(%1)"
297 		: "=m" (ctl_buf)
298 		: "a" (&dw_psw), "a" (&ctl_buf), "m" (dw_psw) : "cc");
299 #else /* CONFIG_64BIT */
300 	asm volatile(
301 		"	stctg	0,0,0(%2)\n"
302 		"	ni	4(%2),0xef\n"	/* switch off protection */
303 		"	lctlg	0,0,0(%2)\n"
304 		"	lghi	1,0x1000\n"
305 		"	stpt	0x328(1)\n"	/* store timer */
306 		"	stckc	0x330(1)\n"	/* store clock comparator */
307 		"	stpx	0x318(1)\n"	/* store prefix register */
308 		"	stam	0,15,0x340(1)\n"/* store access registers */
309 		"	stfpc	0x31c(1)\n"	/* store fpu control */
310 		"	std	0,0x200(1)\n"	/* store f0 */
311 		"	std	1,0x208(1)\n"	/* store f1 */
312 		"	std	2,0x210(1)\n"	/* store f2 */
313 		"	std	3,0x218(1)\n"	/* store f3 */
314 		"	std	4,0x220(1)\n"	/* store f4 */
315 		"	std	5,0x228(1)\n"	/* store f5 */
316 		"	std	6,0x230(1)\n"	/* store f6 */
317 		"	std	7,0x238(1)\n"	/* store f7 */
318 		"	std	8,0x240(1)\n"	/* store f8 */
319 		"	std	9,0x248(1)\n"	/* store f9 */
320 		"	std	10,0x250(1)\n"	/* store f10 */
321 		"	std	11,0x258(1)\n"	/* store f11 */
322 		"	std	12,0x260(1)\n"	/* store f12 */
323 		"	std	13,0x268(1)\n"	/* store f13 */
324 		"	std	14,0x270(1)\n"	/* store f14 */
325 		"	std	15,0x278(1)\n"	/* store f15 */
326 		"	stmg	0,15,0x280(1)\n"/* store general registers */
327 		"	stctg	0,15,0x380(1)\n"/* store control registers */
328 		"	oi	0x384(1),0x10\n"/* fake protection bit */
329 		"	lpswe	0(%1)"
330 		: "=m" (ctl_buf)
331 		: "a" (&dw_psw), "a" (&ctl_buf), "m" (dw_psw) : "cc", "0", "1");
332 #endif /* CONFIG_64BIT */
333 	while (1);
334 }
335 
336 /*
337  * Use to set psw mask except for the first byte which
338  * won't be changed by this function.
339  */
340 static inline void
341 __set_psw_mask(unsigned long mask)
342 {
343 	__load_psw_mask(mask | (arch_local_save_flags() & ~(-1UL >> 8)));
344 }
345 
346 #define local_mcck_enable() \
347 	__set_psw_mask(psw_kernel_bits | PSW_MASK_DAT | PSW_MASK_MCHECK)
348 #define local_mcck_disable() \
349 	__set_psw_mask(psw_kernel_bits | PSW_MASK_DAT)
350 
351 /*
352  * Basic Machine Check/Program Check Handler.
353  */
354 
355 extern void s390_base_mcck_handler(void);
356 extern void s390_base_pgm_handler(void);
357 extern void s390_base_ext_handler(void);
358 
359 extern void (*s390_base_mcck_handler_fn)(void);
360 extern void (*s390_base_pgm_handler_fn)(void);
361 extern void (*s390_base_ext_handler_fn)(void);
362 
363 #define ARCH_LOW_ADDRESS_LIMIT	0x7fffffffUL
364 
365 extern int memcpy_real(void *, void *, size_t);
366 extern void memcpy_absolute(void *, void *, size_t);
367 
368 #define mem_assign_absolute(dest, val) {			\
369 	__typeof__(dest) __tmp = (val);				\
370 								\
371 	BUILD_BUG_ON(sizeof(__tmp) != sizeof(val));		\
372 	memcpy_absolute(&(dest), &__tmp, sizeof(__tmp));	\
373 }
374 
375 /*
376  * Helper macro for exception table entries
377  */
378 #define EX_TABLE(_fault, _target)	\
379 	".section __ex_table,\"a\"\n"	\
380 	".align	4\n"			\
381 	".long	(" #_fault ") - .\n"	\
382 	".long	(" #_target ") - .\n"	\
383 	".previous\n"
384 
385 #else /* __ASSEMBLY__ */
386 
387 #define EX_TABLE(_fault, _target)	\
388 	.section __ex_table,"a"	;	\
389 	.align	4 ;			\
390 	.long	(_fault) - . ;		\
391 	.long	(_target) - . ;		\
392 	.previous
393 
394 #endif /* __ASSEMBLY__ */
395 
396 #endif /* __ASM_S390_PROCESSOR_H */
397