xref: /linux/arch/s390/include/asm/processor.h (revision c0e297dc61f8d4453e07afbea1fa8d0e67cd4a34)
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 #ifndef __ASSEMBLY__
23 
24 #include <linux/linkage.h>
25 #include <linux/irqflags.h>
26 #include <asm/cpu.h>
27 #include <asm/page.h>
28 #include <asm/ptrace.h>
29 #include <asm/setup.h>
30 #include <asm/runtime_instr.h>
31 
32 static inline void set_cpu_flag(int flag)
33 {
34 	S390_lowcore.cpu_flags |= (1U << flag);
35 }
36 
37 static inline void clear_cpu_flag(int flag)
38 {
39 	S390_lowcore.cpu_flags &= ~(1U << flag);
40 }
41 
42 static inline int test_cpu_flag(int flag)
43 {
44 	return !!(S390_lowcore.cpu_flags & (1U << flag));
45 }
46 
47 #define arch_needs_cpu() test_cpu_flag(CIF_NOHZ_DELAY)
48 
49 /*
50  * Default implementation of macro that returns current
51  * instruction pointer ("program counter").
52  */
53 #define current_text_addr() ({ void *pc; asm("basr %0,0" : "=a" (pc)); pc; })
54 
55 static inline void get_cpu_id(struct cpuid *ptr)
56 {
57 	asm volatile("stidp %0" : "=Q" (*ptr));
58 }
59 
60 extern void s390_adjust_jiffies(void);
61 extern const struct seq_operations cpuinfo_op;
62 extern int sysctl_ieee_emulation_warnings;
63 extern void execve_tail(void);
64 
65 /*
66  * User space process size: 2GB for 31 bit, 4TB or 8PT for 64 bit.
67  */
68 
69 #define TASK_SIZE_OF(tsk)	((tsk)->mm->context.asce_limit)
70 #define TASK_UNMAPPED_BASE	(test_thread_flag(TIF_31BIT) ? \
71 					(1UL << 30) : (1UL << 41))
72 #define TASK_SIZE		TASK_SIZE_OF(current)
73 #define TASK_MAX_SIZE		(1UL << 53)
74 
75 #define STACK_TOP		(1UL << (test_thread_flag(TIF_31BIT) ? 31:42))
76 #define STACK_TOP_MAX		(1UL << 42)
77 
78 #define HAVE_ARCH_PICK_MMAP_LAYOUT
79 
80 typedef struct {
81         __u32 ar4;
82 } mm_segment_t;
83 
84 /*
85  * Thread structure
86  */
87 struct thread_struct {
88 	s390_fp_regs fp_regs;
89 	unsigned int  acrs[NUM_ACRS];
90         unsigned long ksp;              /* kernel stack pointer             */
91 	mm_segment_t mm_segment;
92 	unsigned long gmap_addr;	/* address of last gmap fault. */
93 	unsigned int gmap_pfault;	/* signal of a pending guest pfault */
94 	struct per_regs per_user;	/* User specified PER registers */
95 	struct per_event per_event;	/* Cause of the last PER trap */
96 	unsigned long per_flags;	/* Flags to control debug behavior */
97         /* pfault_wait is used to block the process on a pfault event */
98 	unsigned long pfault_wait;
99 	struct list_head list;
100 	/* cpu runtime instrumentation */
101 	struct runtime_instr_cb *ri_cb;
102 	int ri_signum;
103 	unsigned char trap_tdb[256];	/* Transaction abort diagnose block */
104 	__vector128 *vxrs;		/* Vector register save area */
105 };
106 
107 /* Flag to disable transactions. */
108 #define PER_FLAG_NO_TE			1UL
109 /* Flag to enable random transaction aborts. */
110 #define PER_FLAG_TE_ABORT_RAND		2UL
111 /* Flag to specify random transaction abort mode:
112  * - abort each transaction at a random instruction before TEND if set.
113  * - abort random transactions at a random instruction if cleared.
114  */
115 #define PER_FLAG_TE_ABORT_RAND_TEND	4UL
116 
117 typedef struct thread_struct thread_struct;
118 
119 /*
120  * Stack layout of a C stack frame.
121  */
122 #ifndef __PACK_STACK
123 struct stack_frame {
124 	unsigned long back_chain;
125 	unsigned long empty1[5];
126 	unsigned long gprs[10];
127 	unsigned int  empty2[8];
128 };
129 #else
130 struct stack_frame {
131 	unsigned long empty1[5];
132 	unsigned int  empty2[8];
133 	unsigned long gprs[10];
134 	unsigned long back_chain;
135 };
136 #endif
137 
138 #define ARCH_MIN_TASKALIGN	8
139 
140 #define INIT_THREAD {							\
141 	.ksp = sizeof(init_stack) + (unsigned long) &init_stack,	\
142 }
143 
144 /*
145  * Do necessary setup to start up a new thread.
146  */
147 #define start_thread(regs, new_psw, new_stackp) do {			\
148 	regs->psw.mask	= PSW_USER_BITS | PSW_MASK_EA | PSW_MASK_BA;	\
149 	regs->psw.addr	= new_psw | PSW_ADDR_AMODE;			\
150 	regs->gprs[15]	= new_stackp;					\
151 	execve_tail();							\
152 } while (0)
153 
154 #define start_thread31(regs, new_psw, new_stackp) do {			\
155 	regs->psw.mask	= PSW_USER_BITS | PSW_MASK_BA;			\
156 	regs->psw.addr	= new_psw | PSW_ADDR_AMODE;			\
157 	regs->gprs[15]	= new_stackp;					\
158 	crst_table_downgrade(current->mm, 1UL << 31);			\
159 	execve_tail();							\
160 } while (0)
161 
162 /* Forward declaration, a strange C thing */
163 struct task_struct;
164 struct mm_struct;
165 struct seq_file;
166 
167 void show_cacheinfo(struct seq_file *m);
168 
169 /* Free all resources held by a thread. */
170 extern void release_thread(struct task_struct *);
171 
172 /*
173  * Return saved PC of a blocked thread.
174  */
175 extern unsigned long thread_saved_pc(struct task_struct *t);
176 
177 unsigned long get_wchan(struct task_struct *p);
178 #define task_pt_regs(tsk) ((struct pt_regs *) \
179         (task_stack_page(tsk) + THREAD_SIZE) - 1)
180 #define KSTK_EIP(tsk)	(task_pt_regs(tsk)->psw.addr)
181 #define KSTK_ESP(tsk)	(task_pt_regs(tsk)->gprs[15])
182 
183 /* Has task runtime instrumentation enabled ? */
184 #define is_ri_task(tsk) (!!(tsk)->thread.ri_cb)
185 
186 static inline unsigned short stap(void)
187 {
188 	unsigned short cpu_address;
189 
190 	asm volatile("stap %0" : "=m" (cpu_address));
191 	return cpu_address;
192 }
193 
194 /*
195  * Give up the time slice of the virtual PU.
196  */
197 void cpu_relax(void);
198 
199 #define cpu_relax_lowlatency()  barrier()
200 
201 static inline void psw_set_key(unsigned int key)
202 {
203 	asm volatile("spka 0(%0)" : : "d" (key));
204 }
205 
206 /*
207  * Set PSW to specified value.
208  */
209 static inline void __load_psw(psw_t psw)
210 {
211 	asm volatile("lpswe %0" : : "Q" (psw) : "cc");
212 }
213 
214 /*
215  * Set PSW mask to specified value, while leaving the
216  * PSW addr pointing to the next instruction.
217  */
218 static inline void __load_psw_mask (unsigned long mask)
219 {
220 	unsigned long addr;
221 	psw_t psw;
222 
223 	psw.mask = mask;
224 
225 	asm volatile(
226 		"	larl	%0,1f\n"
227 		"	stg	%0,%O1+8(%R1)\n"
228 		"	lpswe	%1\n"
229 		"1:"
230 		: "=&d" (addr), "=Q" (psw) : "Q" (psw) : "memory", "cc");
231 }
232 
233 /*
234  * Rewind PSW instruction address by specified number of bytes.
235  */
236 static inline unsigned long __rewind_psw(psw_t psw, unsigned long ilc)
237 {
238 	unsigned long mask;
239 
240 	mask = (psw.mask & PSW_MASK_EA) ? -1UL :
241 	       (psw.mask & PSW_MASK_BA) ? (1UL << 31) - 1 :
242 					  (1UL << 24) - 1;
243 	return (psw.addr - ilc) & mask;
244 }
245 
246 /*
247  * Function to stop a processor until the next interrupt occurs
248  */
249 void enabled_wait(void);
250 
251 /*
252  * Function to drop a processor into disabled wait state
253  */
254 static inline void __noreturn disabled_wait(unsigned long code)
255 {
256         unsigned long ctl_buf;
257         psw_t dw_psw;
258 
259 	dw_psw.mask = PSW_MASK_BASE | PSW_MASK_WAIT | PSW_MASK_BA | PSW_MASK_EA;
260         dw_psw.addr = code;
261         /*
262          * Store status and then load disabled wait psw,
263          * the processor is dead afterwards
264          */
265 	asm volatile(
266 		"	stctg	0,0,0(%2)\n"
267 		"	ni	4(%2),0xef\n"	/* switch off protection */
268 		"	lctlg	0,0,0(%2)\n"
269 		"	lghi	1,0x1000\n"
270 		"	stpt	0x328(1)\n"	/* store timer */
271 		"	stckc	0x330(1)\n"	/* store clock comparator */
272 		"	stpx	0x318(1)\n"	/* store prefix register */
273 		"	stam	0,15,0x340(1)\n"/* store access registers */
274 		"	stfpc	0x31c(1)\n"	/* store fpu control */
275 		"	std	0,0x200(1)\n"	/* store f0 */
276 		"	std	1,0x208(1)\n"	/* store f1 */
277 		"	std	2,0x210(1)\n"	/* store f2 */
278 		"	std	3,0x218(1)\n"	/* store f3 */
279 		"	std	4,0x220(1)\n"	/* store f4 */
280 		"	std	5,0x228(1)\n"	/* store f5 */
281 		"	std	6,0x230(1)\n"	/* store f6 */
282 		"	std	7,0x238(1)\n"	/* store f7 */
283 		"	std	8,0x240(1)\n"	/* store f8 */
284 		"	std	9,0x248(1)\n"	/* store f9 */
285 		"	std	10,0x250(1)\n"	/* store f10 */
286 		"	std	11,0x258(1)\n"	/* store f11 */
287 		"	std	12,0x260(1)\n"	/* store f12 */
288 		"	std	13,0x268(1)\n"	/* store f13 */
289 		"	std	14,0x270(1)\n"	/* store f14 */
290 		"	std	15,0x278(1)\n"	/* store f15 */
291 		"	stmg	0,15,0x280(1)\n"/* store general registers */
292 		"	stctg	0,15,0x380(1)\n"/* store control registers */
293 		"	oi	0x384(1),0x10\n"/* fake protection bit */
294 		"	lpswe	0(%1)"
295 		: "=m" (ctl_buf)
296 		: "a" (&dw_psw), "a" (&ctl_buf), "m" (dw_psw) : "cc", "0", "1");
297 	while (1);
298 }
299 
300 /*
301  * Use to set psw mask except for the first byte which
302  * won't be changed by this function.
303  */
304 static inline void
305 __set_psw_mask(unsigned long mask)
306 {
307 	__load_psw_mask(mask | (arch_local_save_flags() & ~(-1UL >> 8)));
308 }
309 
310 #define local_mcck_enable() \
311 	__set_psw_mask(PSW_KERNEL_BITS | PSW_MASK_DAT | PSW_MASK_MCHECK)
312 #define local_mcck_disable() \
313 	__set_psw_mask(PSW_KERNEL_BITS | PSW_MASK_DAT)
314 
315 /*
316  * Basic Machine Check/Program Check Handler.
317  */
318 
319 extern void s390_base_mcck_handler(void);
320 extern void s390_base_pgm_handler(void);
321 extern void s390_base_ext_handler(void);
322 
323 extern void (*s390_base_mcck_handler_fn)(void);
324 extern void (*s390_base_pgm_handler_fn)(void);
325 extern void (*s390_base_ext_handler_fn)(void);
326 
327 #define ARCH_LOW_ADDRESS_LIMIT	0x7fffffffUL
328 
329 extern int memcpy_real(void *, void *, size_t);
330 extern void memcpy_absolute(void *, void *, size_t);
331 
332 #define mem_assign_absolute(dest, val) {			\
333 	__typeof__(dest) __tmp = (val);				\
334 								\
335 	BUILD_BUG_ON(sizeof(__tmp) != sizeof(val));		\
336 	memcpy_absolute(&(dest), &__tmp, sizeof(__tmp));	\
337 }
338 
339 /*
340  * Helper macro for exception table entries
341  */
342 #define EX_TABLE(_fault, _target)	\
343 	".section __ex_table,\"a\"\n"	\
344 	".align	4\n"			\
345 	".long	(" #_fault ") - .\n"	\
346 	".long	(" #_target ") - .\n"	\
347 	".previous\n"
348 
349 #else /* __ASSEMBLY__ */
350 
351 #define EX_TABLE(_fault, _target)	\
352 	.section __ex_table,"a"	;	\
353 	.align	4 ;			\
354 	.long	(_fault) - . ;		\
355 	.long	(_target) - . ;		\
356 	.previous
357 
358 #endif /* __ASSEMBLY__ */
359 
360 #endif /* __ASM_S390_PROCESSOR_H */
361