xref: /openbmc/linux/arch/s390/include/asm/processor.h (revision 8730046c)
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 	unsigned long user_timer;	/* task cputime in user space */
114 	unsigned long system_timer;	/* task cputime in kernel space */
115 	unsigned long sys_call_table;	/* system call table address */
116 	mm_segment_t mm_segment;
117 	unsigned long gmap_addr;	/* address of last gmap fault. */
118 	unsigned int gmap_write_flag;	/* gmap fault write indication */
119 	unsigned int gmap_int_code;	/* int code of last gmap fault */
120 	unsigned int gmap_pfault;	/* signal of a pending guest pfault */
121 	/* Per-thread information related to debugging */
122 	struct per_regs per_user;	/* User specified PER registers */
123 	struct per_event per_event;	/* Cause of the last PER trap */
124 	unsigned long per_flags;	/* Flags to control debug behavior */
125 	unsigned int system_call;	/* system call number in signal */
126 	unsigned long last_break;	/* last breaking-event-address. */
127         /* pfault_wait is used to block the process on a pfault event */
128 	unsigned long pfault_wait;
129 	struct list_head list;
130 	/* cpu runtime instrumentation */
131 	struct runtime_instr_cb *ri_cb;
132 	unsigned char trap_tdb[256];	/* Transaction abort diagnose block */
133 	/*
134 	 * Warning: 'fpu' is dynamically-sized. It *MUST* be at
135 	 * the end.
136 	 */
137 	struct fpu fpu;			/* FP and VX register save area */
138 };
139 
140 /* Flag to disable transactions. */
141 #define PER_FLAG_NO_TE			1UL
142 /* Flag to enable random transaction aborts. */
143 #define PER_FLAG_TE_ABORT_RAND		2UL
144 /* Flag to specify random transaction abort mode:
145  * - abort each transaction at a random instruction before TEND if set.
146  * - abort random transactions at a random instruction if cleared.
147  */
148 #define PER_FLAG_TE_ABORT_RAND_TEND	4UL
149 
150 typedef struct thread_struct thread_struct;
151 
152 /*
153  * Stack layout of a C stack frame.
154  */
155 #ifndef __PACK_STACK
156 struct stack_frame {
157 	unsigned long back_chain;
158 	unsigned long empty1[5];
159 	unsigned long gprs[10];
160 	unsigned int  empty2[8];
161 };
162 #else
163 struct stack_frame {
164 	unsigned long empty1[5];
165 	unsigned int  empty2[8];
166 	unsigned long gprs[10];
167 	unsigned long back_chain;
168 };
169 #endif
170 
171 #define ARCH_MIN_TASKALIGN	8
172 
173 #define INIT_THREAD {							\
174 	.ksp = sizeof(init_stack) + (unsigned long) &init_stack,	\
175 	.fpu.regs = (void *) init_task.thread.fpu.fprs,			\
176 }
177 
178 /*
179  * Do necessary setup to start up a new thread.
180  */
181 #define start_thread(regs, new_psw, new_stackp) do {			\
182 	regs->psw.mask	= PSW_USER_BITS | PSW_MASK_EA | PSW_MASK_BA;	\
183 	regs->psw.addr	= new_psw;					\
184 	regs->gprs[15]	= new_stackp;					\
185 	execve_tail();							\
186 } while (0)
187 
188 #define start_thread31(regs, new_psw, new_stackp) do {			\
189 	regs->psw.mask	= PSW_USER_BITS | PSW_MASK_BA;			\
190 	regs->psw.addr	= new_psw;					\
191 	regs->gprs[15]	= new_stackp;					\
192 	crst_table_downgrade(current->mm);				\
193 	execve_tail();							\
194 } while (0)
195 
196 /* Forward declaration, a strange C thing */
197 struct task_struct;
198 struct mm_struct;
199 struct seq_file;
200 
201 typedef int (*dump_trace_func_t)(void *data, unsigned long address, int reliable);
202 void dump_trace(dump_trace_func_t func, void *data,
203 		struct task_struct *task, unsigned long sp);
204 
205 void show_cacheinfo(struct seq_file *m);
206 
207 /* Free all resources held by a thread. */
208 extern void release_thread(struct task_struct *);
209 
210 /*
211  * Return saved PC of a blocked thread.
212  */
213 extern unsigned long thread_saved_pc(struct task_struct *t);
214 
215 unsigned long get_wchan(struct task_struct *p);
216 #define task_pt_regs(tsk) ((struct pt_regs *) \
217         (task_stack_page(tsk) + THREAD_SIZE) - 1)
218 #define KSTK_EIP(tsk)	(task_pt_regs(tsk)->psw.addr)
219 #define KSTK_ESP(tsk)	(task_pt_regs(tsk)->gprs[15])
220 
221 /* Has task runtime instrumentation enabled ? */
222 #define is_ri_task(tsk) (!!(tsk)->thread.ri_cb)
223 
224 static inline unsigned long current_stack_pointer(void)
225 {
226 	unsigned long sp;
227 
228 	asm volatile("la %0,0(15)" : "=a" (sp));
229 	return sp;
230 }
231 
232 static inline unsigned short stap(void)
233 {
234 	unsigned short cpu_address;
235 
236 	asm volatile("stap %0" : "=m" (cpu_address));
237 	return cpu_address;
238 }
239 
240 /*
241  * Give up the time slice of the virtual PU.
242  */
243 #define cpu_relax_yield cpu_relax_yield
244 void cpu_relax_yield(void);
245 
246 #define cpu_relax() barrier()
247 
248 #define ECAG_CACHE_ATTRIBUTE	0
249 #define ECAG_CPU_ATTRIBUTE	1
250 
251 static inline unsigned long __ecag(unsigned int asi, unsigned char parm)
252 {
253 	unsigned long val;
254 
255 	asm volatile(".insn	rsy,0xeb000000004c,%0,0,0(%1)" /* ecag */
256 		     : "=d" (val) : "a" (asi << 8 | parm));
257 	return val;
258 }
259 
260 static inline void psw_set_key(unsigned int key)
261 {
262 	asm volatile("spka 0(%0)" : : "d" (key));
263 }
264 
265 /*
266  * Set PSW to specified value.
267  */
268 static inline void __load_psw(psw_t psw)
269 {
270 	asm volatile("lpswe %0" : : "Q" (psw) : "cc");
271 }
272 
273 /*
274  * Set PSW mask to specified value, while leaving the
275  * PSW addr pointing to the next instruction.
276  */
277 static inline void __load_psw_mask(unsigned long mask)
278 {
279 	unsigned long addr;
280 	psw_t psw;
281 
282 	psw.mask = mask;
283 
284 	asm volatile(
285 		"	larl	%0,1f\n"
286 		"	stg	%0,%O1+8(%R1)\n"
287 		"	lpswe	%1\n"
288 		"1:"
289 		: "=&d" (addr), "=Q" (psw) : "Q" (psw) : "memory", "cc");
290 }
291 
292 /*
293  * Extract current PSW mask
294  */
295 static inline unsigned long __extract_psw(void)
296 {
297 	unsigned int reg1, reg2;
298 
299 	asm volatile("epsw %0,%1" : "=d" (reg1), "=a" (reg2));
300 	return (((unsigned long) reg1) << 32) | ((unsigned long) reg2);
301 }
302 
303 static inline void local_mcck_enable(void)
304 {
305 	__load_psw_mask(__extract_psw() | PSW_MASK_MCHECK);
306 }
307 
308 static inline void local_mcck_disable(void)
309 {
310 	__load_psw_mask(__extract_psw() & ~PSW_MASK_MCHECK);
311 }
312 
313 /*
314  * Rewind PSW instruction address by specified number of bytes.
315  */
316 static inline unsigned long __rewind_psw(psw_t psw, unsigned long ilc)
317 {
318 	unsigned long mask;
319 
320 	mask = (psw.mask & PSW_MASK_EA) ? -1UL :
321 	       (psw.mask & PSW_MASK_BA) ? (1UL << 31) - 1 :
322 					  (1UL << 24) - 1;
323 	return (psw.addr - ilc) & mask;
324 }
325 
326 /*
327  * Function to stop a processor until the next interrupt occurs
328  */
329 void enabled_wait(void);
330 
331 /*
332  * Function to drop a processor into disabled wait state
333  */
334 static inline void __noreturn disabled_wait(unsigned long code)
335 {
336 	psw_t psw;
337 
338 	psw.mask = PSW_MASK_BASE | PSW_MASK_WAIT | PSW_MASK_BA | PSW_MASK_EA;
339 	psw.addr = code;
340 	__load_psw(psw);
341 	while (1);
342 }
343 
344 /*
345  * Basic Machine Check/Program Check Handler.
346  */
347 
348 extern void s390_base_mcck_handler(void);
349 extern void s390_base_pgm_handler(void);
350 extern void s390_base_ext_handler(void);
351 
352 extern void (*s390_base_mcck_handler_fn)(void);
353 extern void (*s390_base_pgm_handler_fn)(void);
354 extern void (*s390_base_ext_handler_fn)(void);
355 
356 #define ARCH_LOW_ADDRESS_LIMIT	0x7fffffffUL
357 
358 extern int memcpy_real(void *, void *, size_t);
359 extern void memcpy_absolute(void *, void *, size_t);
360 
361 #define mem_assign_absolute(dest, val) {			\
362 	__typeof__(dest) __tmp = (val);				\
363 								\
364 	BUILD_BUG_ON(sizeof(__tmp) != sizeof(val));		\
365 	memcpy_absolute(&(dest), &__tmp, sizeof(__tmp));	\
366 }
367 
368 #endif /* __ASSEMBLY__ */
369 
370 #endif /* __ASM_S390_PROCESSOR_H */
371