xref: /linux/arch/s390/include/asm/processor.h (revision b85d45947951d23cb22d90caecf4c1eb81342c96)
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 #define CIF_FPU			3	/* restore vector registers */
18 
19 #define _CIF_MCCK_PENDING	(1<<CIF_MCCK_PENDING)
20 #define _CIF_ASCE		(1<<CIF_ASCE)
21 #define _CIF_NOHZ_DELAY		(1<<CIF_NOHZ_DELAY)
22 #define _CIF_FPU		(1<<CIF_FPU)
23 
24 #ifndef __ASSEMBLY__
25 
26 #include <linux/linkage.h>
27 #include <linux/irqflags.h>
28 #include <asm/cpu.h>
29 #include <asm/page.h>
30 #include <asm/ptrace.h>
31 #include <asm/setup.h>
32 #include <asm/runtime_instr.h>
33 #include <asm/fpu-internal.h>
34 
35 static inline void set_cpu_flag(int flag)
36 {
37 	S390_lowcore.cpu_flags |= (1U << flag);
38 }
39 
40 static inline void clear_cpu_flag(int flag)
41 {
42 	S390_lowcore.cpu_flags &= ~(1U << flag);
43 }
44 
45 static inline int test_cpu_flag(int flag)
46 {
47 	return !!(S390_lowcore.cpu_flags & (1U << flag));
48 }
49 
50 #define arch_needs_cpu() test_cpu_flag(CIF_NOHZ_DELAY)
51 
52 /*
53  * Default implementation of macro that returns current
54  * instruction pointer ("program counter").
55  */
56 #define current_text_addr() ({ void *pc; asm("basr %0,0" : "=a" (pc)); pc; })
57 
58 static inline void get_cpu_id(struct cpuid *ptr)
59 {
60 	asm volatile("stidp %0" : "=Q" (*ptr));
61 }
62 
63 extern void s390_adjust_jiffies(void);
64 extern const struct seq_operations cpuinfo_op;
65 extern int sysctl_ieee_emulation_warnings;
66 extern void execve_tail(void);
67 
68 /*
69  * User space process size: 2GB for 31 bit, 4TB or 8PT for 64 bit.
70  */
71 
72 #define TASK_SIZE_OF(tsk)	((tsk)->mm->context.asce_limit)
73 #define TASK_UNMAPPED_BASE	(test_thread_flag(TIF_31BIT) ? \
74 					(1UL << 30) : (1UL << 41))
75 #define TASK_SIZE		TASK_SIZE_OF(current)
76 #define TASK_MAX_SIZE		(1UL << 53)
77 
78 #define STACK_TOP		(1UL << (test_thread_flag(TIF_31BIT) ? 31:42))
79 #define STACK_TOP_MAX		(1UL << 42)
80 
81 #define HAVE_ARCH_PICK_MMAP_LAYOUT
82 
83 typedef struct {
84         __u32 ar4;
85 } mm_segment_t;
86 
87 /*
88  * Thread structure
89  */
90 struct thread_struct {
91 	struct fpu fpu;			/* FP and VX register save area */
92 	unsigned int  acrs[NUM_ACRS];
93         unsigned long ksp;              /* kernel stack pointer             */
94 	mm_segment_t mm_segment;
95 	unsigned long gmap_addr;	/* address of last gmap fault. */
96 	unsigned int gmap_pfault;	/* signal of a pending guest pfault */
97 	struct per_regs per_user;	/* User specified PER registers */
98 	struct per_event per_event;	/* Cause of the last PER trap */
99 	unsigned long per_flags;	/* Flags to control debug behavior */
100         /* pfault_wait is used to block the process on a pfault event */
101 	unsigned long pfault_wait;
102 	struct list_head list;
103 	/* cpu runtime instrumentation */
104 	struct runtime_instr_cb *ri_cb;
105 	int ri_signum;
106 	unsigned char trap_tdb[256];	/* Transaction abort diagnose block */
107 };
108 
109 /* Flag to disable transactions. */
110 #define PER_FLAG_NO_TE			1UL
111 /* Flag to enable random transaction aborts. */
112 #define PER_FLAG_TE_ABORT_RAND		2UL
113 /* Flag to specify random transaction abort mode:
114  * - abort each transaction at a random instruction before TEND if set.
115  * - abort random transactions at a random instruction if cleared.
116  */
117 #define PER_FLAG_TE_ABORT_RAND_TEND	4UL
118 
119 typedef struct thread_struct thread_struct;
120 
121 /*
122  * Stack layout of a C stack frame.
123  */
124 #ifndef __PACK_STACK
125 struct stack_frame {
126 	unsigned long back_chain;
127 	unsigned long empty1[5];
128 	unsigned long gprs[10];
129 	unsigned int  empty2[8];
130 };
131 #else
132 struct stack_frame {
133 	unsigned long empty1[5];
134 	unsigned int  empty2[8];
135 	unsigned long gprs[10];
136 	unsigned long back_chain;
137 };
138 #endif
139 
140 #define ARCH_MIN_TASKALIGN	8
141 
142 #define INIT_THREAD {							\
143 	.ksp = sizeof(init_stack) + (unsigned long) &init_stack,	\
144 }
145 
146 /*
147  * Do necessary setup to start up a new thread.
148  */
149 #define start_thread(regs, new_psw, new_stackp) do {			\
150 	regs->psw.mask	= PSW_USER_BITS | PSW_MASK_EA | PSW_MASK_BA;	\
151 	regs->psw.addr	= new_psw | PSW_ADDR_AMODE;			\
152 	regs->gprs[15]	= new_stackp;					\
153 	execve_tail();							\
154 } while (0)
155 
156 #define start_thread31(regs, new_psw, new_stackp) do {			\
157 	regs->psw.mask	= PSW_USER_BITS | PSW_MASK_BA;			\
158 	regs->psw.addr	= new_psw | PSW_ADDR_AMODE;			\
159 	regs->gprs[15]	= new_stackp;					\
160 	crst_table_downgrade(current->mm, 1UL << 31);			\
161 	execve_tail();							\
162 } while (0)
163 
164 /* Forward declaration, a strange C thing */
165 struct task_struct;
166 struct mm_struct;
167 struct seq_file;
168 
169 void show_cacheinfo(struct seq_file *m);
170 
171 /* Free all resources held by a thread. */
172 extern void release_thread(struct task_struct *);
173 
174 /*
175  * Return saved PC of a blocked thread.
176  */
177 extern unsigned long thread_saved_pc(struct task_struct *t);
178 
179 unsigned long get_wchan(struct task_struct *p);
180 #define task_pt_regs(tsk) ((struct pt_regs *) \
181         (task_stack_page(tsk) + THREAD_SIZE) - 1)
182 #define KSTK_EIP(tsk)	(task_pt_regs(tsk)->psw.addr)
183 #define KSTK_ESP(tsk)	(task_pt_regs(tsk)->gprs[15])
184 
185 /* Has task runtime instrumentation enabled ? */
186 #define is_ri_task(tsk) (!!(tsk)->thread.ri_cb)
187 
188 static inline unsigned short stap(void)
189 {
190 	unsigned short cpu_address;
191 
192 	asm volatile("stap %0" : "=m" (cpu_address));
193 	return cpu_address;
194 }
195 
196 /*
197  * Give up the time slice of the virtual PU.
198  */
199 void cpu_relax(void);
200 
201 #define cpu_relax_lowlatency()  barrier()
202 
203 static inline void psw_set_key(unsigned int key)
204 {
205 	asm volatile("spka 0(%0)" : : "d" (key));
206 }
207 
208 /*
209  * Set PSW to specified value.
210  */
211 static inline void __load_psw(psw_t psw)
212 {
213 	asm volatile("lpswe %0" : : "Q" (psw) : "cc");
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 	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 }
234 
235 /*
236  * Extract current PSW mask
237  */
238 static inline unsigned long __extract_psw(void)
239 {
240 	unsigned int reg1, reg2;
241 
242 	asm volatile("epsw %0,%1" : "=d" (reg1), "=a" (reg2));
243 	return (((unsigned long) reg1) << 32) | ((unsigned long) reg2);
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 	unsigned long mask;
252 
253 	mask = (psw.mask & PSW_MASK_EA) ? -1UL :
254 	       (psw.mask & PSW_MASK_BA) ? (1UL << 31) - 1 :
255 					  (1UL << 24) - 1;
256 	return (psw.addr - ilc) & mask;
257 }
258 
259 /*
260  * Function to stop a processor until the next interrupt occurs
261  */
262 void enabled_wait(void);
263 
264 /*
265  * Function to drop a processor into disabled wait state
266  */
267 static inline void __noreturn disabled_wait(unsigned long code)
268 {
269         unsigned long ctl_buf;
270         psw_t dw_psw;
271 
272 	dw_psw.mask = PSW_MASK_BASE | PSW_MASK_WAIT | PSW_MASK_BA | PSW_MASK_EA;
273         dw_psw.addr = code;
274         /*
275          * Store status and then load disabled wait psw,
276          * the processor is dead afterwards
277          */
278 	asm volatile(
279 		"	stctg	0,0,0(%2)\n"
280 		"	ni	4(%2),0xef\n"	/* switch off protection */
281 		"	lctlg	0,0,0(%2)\n"
282 		"	lghi	1,0x1000\n"
283 		"	stpt	0x328(1)\n"	/* store timer */
284 		"	stckc	0x330(1)\n"	/* store clock comparator */
285 		"	stpx	0x318(1)\n"	/* store prefix register */
286 		"	stam	0,15,0x340(1)\n"/* store access registers */
287 		"	stfpc	0x31c(1)\n"	/* store fpu control */
288 		"	std	0,0x200(1)\n"	/* store f0 */
289 		"	std	1,0x208(1)\n"	/* store f1 */
290 		"	std	2,0x210(1)\n"	/* store f2 */
291 		"	std	3,0x218(1)\n"	/* store f3 */
292 		"	std	4,0x220(1)\n"	/* store f4 */
293 		"	std	5,0x228(1)\n"	/* store f5 */
294 		"	std	6,0x230(1)\n"	/* store f6 */
295 		"	std	7,0x238(1)\n"	/* store f7 */
296 		"	std	8,0x240(1)\n"	/* store f8 */
297 		"	std	9,0x248(1)\n"	/* store f9 */
298 		"	std	10,0x250(1)\n"	/* store f10 */
299 		"	std	11,0x258(1)\n"	/* store f11 */
300 		"	std	12,0x260(1)\n"	/* store f12 */
301 		"	std	13,0x268(1)\n"	/* store f13 */
302 		"	std	14,0x270(1)\n"	/* store f14 */
303 		"	std	15,0x278(1)\n"	/* store f15 */
304 		"	stmg	0,15,0x280(1)\n"/* store general registers */
305 		"	stctg	0,15,0x380(1)\n"/* store control registers */
306 		"	oi	0x384(1),0x10\n"/* fake protection bit */
307 		"	lpswe	0(%1)"
308 		: "=m" (ctl_buf)
309 		: "a" (&dw_psw), "a" (&ctl_buf), "m" (dw_psw) : "cc", "0", "1");
310 	while (1);
311 }
312 
313 /*
314  * Use to set psw mask except for the first byte which
315  * won't be changed by this function.
316  */
317 static inline void
318 __set_psw_mask(unsigned long mask)
319 {
320 	__load_psw_mask(mask | (arch_local_save_flags() & ~(-1UL >> 8)));
321 }
322 
323 #define local_mcck_enable() \
324 	__set_psw_mask(PSW_KERNEL_BITS | PSW_MASK_DAT | PSW_MASK_MCHECK)
325 #define local_mcck_disable() \
326 	__set_psw_mask(PSW_KERNEL_BITS | PSW_MASK_DAT)
327 
328 /*
329  * Basic Machine Check/Program Check Handler.
330  */
331 
332 extern void s390_base_mcck_handler(void);
333 extern void s390_base_pgm_handler(void);
334 extern void s390_base_ext_handler(void);
335 
336 extern void (*s390_base_mcck_handler_fn)(void);
337 extern void (*s390_base_pgm_handler_fn)(void);
338 extern void (*s390_base_ext_handler_fn)(void);
339 
340 #define ARCH_LOW_ADDRESS_LIMIT	0x7fffffffUL
341 
342 extern int memcpy_real(void *, void *, size_t);
343 extern void memcpy_absolute(void *, void *, size_t);
344 
345 #define mem_assign_absolute(dest, val) {			\
346 	__typeof__(dest) __tmp = (val);				\
347 								\
348 	BUILD_BUG_ON(sizeof(__tmp) != sizeof(val));		\
349 	memcpy_absolute(&(dest), &__tmp, sizeof(__tmp));	\
350 }
351 
352 #endif /* __ASSEMBLY__ */
353 
354 #endif /* __ASM_S390_PROCESSOR_H */
355