xref: /linux/arch/s390/include/asm/processor.h (revision 071bf69a0220253a44acb8b2a27f7a262b9a46bf)
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 #include <linux/const.h>
15 
16 #define CIF_MCCK_PENDING	0	/* machine check handling is pending */
17 #define CIF_ASCE		1	/* user asce needs fixup / uaccess */
18 #define CIF_NOHZ_DELAY		2	/* delay HZ disable for a tick */
19 #define CIF_FPU			3	/* restore FPU registers */
20 #define CIF_IGNORE_IRQ		4	/* ignore interrupt (for udelay) */
21 #define CIF_ENABLED_WAIT	5	/* in enabled wait state */
22 
23 #define _CIF_MCCK_PENDING	_BITUL(CIF_MCCK_PENDING)
24 #define _CIF_ASCE		_BITUL(CIF_ASCE)
25 #define _CIF_NOHZ_DELAY		_BITUL(CIF_NOHZ_DELAY)
26 #define _CIF_FPU		_BITUL(CIF_FPU)
27 #define _CIF_IGNORE_IRQ		_BITUL(CIF_IGNORE_IRQ)
28 #define _CIF_ENABLED_WAIT	_BITUL(CIF_ENABLED_WAIT)
29 
30 #ifndef __ASSEMBLY__
31 
32 #include <linux/linkage.h>
33 #include <linux/irqflags.h>
34 #include <asm/cpu.h>
35 #include <asm/page.h>
36 #include <asm/ptrace.h>
37 #include <asm/setup.h>
38 #include <asm/runtime_instr.h>
39 #include <asm/fpu/types.h>
40 #include <asm/fpu/internal.h>
41 
42 static inline void set_cpu_flag(int flag)
43 {
44 	S390_lowcore.cpu_flags |= (1UL << flag);
45 }
46 
47 static inline void clear_cpu_flag(int flag)
48 {
49 	S390_lowcore.cpu_flags &= ~(1UL << flag);
50 }
51 
52 static inline int test_cpu_flag(int flag)
53 {
54 	return !!(S390_lowcore.cpu_flags & (1UL << flag));
55 }
56 
57 /*
58  * Test CIF flag of another CPU. The caller needs to ensure that
59  * CPU hotplug can not happen, e.g. by disabling preemption.
60  */
61 static inline int test_cpu_flag_of(int flag, int cpu)
62 {
63 	struct lowcore *lc = lowcore_ptr[cpu];
64 	return !!(lc->cpu_flags & (1UL << flag));
65 }
66 
67 #define arch_needs_cpu() test_cpu_flag(CIF_NOHZ_DELAY)
68 
69 /*
70  * Default implementation of macro that returns current
71  * instruction pointer ("program counter").
72  */
73 #define current_text_addr() ({ void *pc; asm("basr %0,0" : "=a" (pc)); pc; })
74 
75 static inline void get_cpu_id(struct cpuid *ptr)
76 {
77 	asm volatile("stidp %0" : "=Q" (*ptr));
78 }
79 
80 void s390_adjust_jiffies(void);
81 void s390_update_cpu_mhz(void);
82 void cpu_detect_mhz_feature(void);
83 
84 extern const struct seq_operations cpuinfo_op;
85 extern int sysctl_ieee_emulation_warnings;
86 extern void execve_tail(void);
87 
88 /*
89  * User space process size: 2GB for 31 bit, 4TB or 8PT for 64 bit.
90  */
91 
92 #define TASK_SIZE_OF(tsk)	((tsk)->mm->context.asce_limit)
93 #define TASK_UNMAPPED_BASE	(test_thread_flag(TIF_31BIT) ? \
94 					(1UL << 30) : (1UL << 41))
95 #define TASK_SIZE		TASK_SIZE_OF(current)
96 #define TASK_MAX_SIZE		(1UL << 53)
97 
98 #define STACK_TOP		(1UL << (test_thread_flag(TIF_31BIT) ? 31:42))
99 #define STACK_TOP_MAX		(1UL << 42)
100 
101 #define HAVE_ARCH_PICK_MMAP_LAYOUT
102 
103 typedef struct {
104         __u32 ar4;
105 } mm_segment_t;
106 
107 /*
108  * Thread structure
109  */
110 struct thread_struct {
111 	unsigned int  acrs[NUM_ACRS];
112         unsigned long ksp;              /* kernel stack pointer             */
113 	mm_segment_t mm_segment;
114 	unsigned long gmap_addr;	/* address of last gmap fault. */
115 	unsigned int gmap_write_flag;	/* gmap fault write indication */
116 	unsigned int gmap_int_code;	/* int code of last gmap fault */
117 	unsigned int gmap_pfault;	/* signal of a pending guest pfault */
118 	struct per_regs per_user;	/* User specified PER registers */
119 	struct per_event per_event;	/* Cause of the last PER trap */
120 	unsigned long per_flags;	/* Flags to control debug behavior */
121         /* pfault_wait is used to block the process on a pfault event */
122 	unsigned long pfault_wait;
123 	struct list_head list;
124 	/* cpu runtime instrumentation */
125 	struct runtime_instr_cb *ri_cb;
126 	unsigned char trap_tdb[256];	/* Transaction abort diagnose block */
127 	/*
128 	 * Warning: 'fpu' is dynamically-sized. It *MUST* be at
129 	 * the end.
130 	 */
131 	struct fpu fpu;			/* FP and VX register save area */
132 };
133 
134 /* Flag to disable transactions. */
135 #define PER_FLAG_NO_TE			1UL
136 /* Flag to enable random transaction aborts. */
137 #define PER_FLAG_TE_ABORT_RAND		2UL
138 /* Flag to specify random transaction abort mode:
139  * - abort each transaction at a random instruction before TEND if set.
140  * - abort random transactions at a random instruction if cleared.
141  */
142 #define PER_FLAG_TE_ABORT_RAND_TEND	4UL
143 
144 typedef struct thread_struct thread_struct;
145 
146 /*
147  * Stack layout of a C stack frame.
148  */
149 #ifndef __PACK_STACK
150 struct stack_frame {
151 	unsigned long back_chain;
152 	unsigned long empty1[5];
153 	unsigned long gprs[10];
154 	unsigned int  empty2[8];
155 };
156 #else
157 struct stack_frame {
158 	unsigned long empty1[5];
159 	unsigned int  empty2[8];
160 	unsigned long gprs[10];
161 	unsigned long back_chain;
162 };
163 #endif
164 
165 #define ARCH_MIN_TASKALIGN	8
166 
167 #define INIT_THREAD {							\
168 	.ksp = sizeof(init_stack) + (unsigned long) &init_stack,	\
169 	.fpu.regs = (void *) init_task.thread.fpu.fprs,			\
170 }
171 
172 /*
173  * Do necessary setup to start up a new thread.
174  */
175 #define start_thread(regs, new_psw, new_stackp) do {			\
176 	regs->psw.mask	= PSW_USER_BITS | PSW_MASK_EA | PSW_MASK_BA;	\
177 	regs->psw.addr	= new_psw;					\
178 	regs->gprs[15]	= new_stackp;					\
179 	execve_tail();							\
180 } while (0)
181 
182 #define start_thread31(regs, new_psw, new_stackp) do {			\
183 	regs->psw.mask	= PSW_USER_BITS | PSW_MASK_BA;			\
184 	regs->psw.addr	= new_psw;					\
185 	regs->gprs[15]	= new_stackp;					\
186 	crst_table_downgrade(current->mm);				\
187 	execve_tail();							\
188 } while (0)
189 
190 /* Forward declaration, a strange C thing */
191 struct task_struct;
192 struct mm_struct;
193 struct seq_file;
194 
195 typedef int (*dump_trace_func_t)(void *data, unsigned long address);
196 void dump_trace(dump_trace_func_t func, void *data,
197 		struct task_struct *task, unsigned long sp);
198 
199 void show_cacheinfo(struct seq_file *m);
200 
201 /* Free all resources held by a thread. */
202 extern void release_thread(struct task_struct *);
203 
204 /*
205  * Return saved PC of a blocked thread.
206  */
207 extern unsigned long thread_saved_pc(struct task_struct *t);
208 
209 unsigned long get_wchan(struct task_struct *p);
210 #define task_pt_regs(tsk) ((struct pt_regs *) \
211         (task_stack_page(tsk) + THREAD_SIZE) - 1)
212 #define KSTK_EIP(tsk)	(task_pt_regs(tsk)->psw.addr)
213 #define KSTK_ESP(tsk)	(task_pt_regs(tsk)->gprs[15])
214 
215 /* Has task runtime instrumentation enabled ? */
216 #define is_ri_task(tsk) (!!(tsk)->thread.ri_cb)
217 
218 static inline unsigned long current_stack_pointer(void)
219 {
220 	unsigned long sp;
221 
222 	asm volatile("la %0,0(15)" : "=a" (sp));
223 	return sp;
224 }
225 
226 static inline unsigned short stap(void)
227 {
228 	unsigned short cpu_address;
229 
230 	asm volatile("stap %0" : "=m" (cpu_address));
231 	return cpu_address;
232 }
233 
234 /*
235  * Give up the time slice of the virtual PU.
236  */
237 void cpu_relax(void);
238 
239 #define cpu_relax_lowlatency()  barrier()
240 
241 #define ECAG_CACHE_ATTRIBUTE	0
242 #define ECAG_CPU_ATTRIBUTE	1
243 
244 static inline unsigned long __ecag(unsigned int asi, unsigned char parm)
245 {
246 	unsigned long val;
247 
248 	asm volatile(".insn	rsy,0xeb000000004c,%0,0,0(%1)" /* ecag */
249 		     : "=d" (val) : "a" (asi << 8 | parm));
250 	return val;
251 }
252 
253 static inline void psw_set_key(unsigned int key)
254 {
255 	asm volatile("spka 0(%0)" : : "d" (key));
256 }
257 
258 /*
259  * Set PSW to specified value.
260  */
261 static inline void __load_psw(psw_t psw)
262 {
263 	asm volatile("lpswe %0" : : "Q" (psw) : "cc");
264 }
265 
266 /*
267  * Set PSW mask to specified value, while leaving the
268  * PSW addr pointing to the next instruction.
269  */
270 static inline void __load_psw_mask(unsigned long mask)
271 {
272 	unsigned long addr;
273 	psw_t psw;
274 
275 	psw.mask = mask;
276 
277 	asm volatile(
278 		"	larl	%0,1f\n"
279 		"	stg	%0,%O1+8(%R1)\n"
280 		"	lpswe	%1\n"
281 		"1:"
282 		: "=&d" (addr), "=Q" (psw) : "Q" (psw) : "memory", "cc");
283 }
284 
285 /*
286  * Extract current PSW mask
287  */
288 static inline unsigned long __extract_psw(void)
289 {
290 	unsigned int reg1, reg2;
291 
292 	asm volatile("epsw %0,%1" : "=d" (reg1), "=a" (reg2));
293 	return (((unsigned long) reg1) << 32) | ((unsigned long) reg2);
294 }
295 
296 static inline void local_mcck_enable(void)
297 {
298 	__load_psw_mask(__extract_psw() | PSW_MASK_MCHECK);
299 }
300 
301 static inline void local_mcck_disable(void)
302 {
303 	__load_psw_mask(__extract_psw() & ~PSW_MASK_MCHECK);
304 }
305 
306 /*
307  * Rewind PSW instruction address by specified number of bytes.
308  */
309 static inline unsigned long __rewind_psw(psw_t psw, unsigned long ilc)
310 {
311 	unsigned long mask;
312 
313 	mask = (psw.mask & PSW_MASK_EA) ? -1UL :
314 	       (psw.mask & PSW_MASK_BA) ? (1UL << 31) - 1 :
315 					  (1UL << 24) - 1;
316 	return (psw.addr - ilc) & mask;
317 }
318 
319 /*
320  * Function to stop a processor until the next interrupt occurs
321  */
322 void enabled_wait(void);
323 
324 /*
325  * Function to drop a processor into disabled wait state
326  */
327 static inline void __noreturn disabled_wait(unsigned long code)
328 {
329 	psw_t psw;
330 
331 	psw.mask = PSW_MASK_BASE | PSW_MASK_WAIT | PSW_MASK_BA | PSW_MASK_EA;
332 	psw.addr = code;
333 	__load_psw(psw);
334 	while (1);
335 }
336 
337 /*
338  * Basic Machine Check/Program Check Handler.
339  */
340 
341 extern void s390_base_mcck_handler(void);
342 extern void s390_base_pgm_handler(void);
343 extern void s390_base_ext_handler(void);
344 
345 extern void (*s390_base_mcck_handler_fn)(void);
346 extern void (*s390_base_pgm_handler_fn)(void);
347 extern void (*s390_base_ext_handler_fn)(void);
348 
349 #define ARCH_LOW_ADDRESS_LIMIT	0x7fffffffUL
350 
351 extern int memcpy_real(void *, void *, size_t);
352 extern void memcpy_absolute(void *, void *, size_t);
353 
354 #define mem_assign_absolute(dest, val) {			\
355 	__typeof__(dest) __tmp = (val);				\
356 								\
357 	BUILD_BUG_ON(sizeof(__tmp) != sizeof(val));		\
358 	memcpy_absolute(&(dest), &__tmp, sizeof(__tmp));	\
359 }
360 
361 #endif /* __ASSEMBLY__ */
362 
363 #endif /* __ASM_S390_PROCESSOR_H */
364