xref: /openbmc/linux/arch/s390/include/asm/processor.h (revision 82e6fdd6)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  *  S390 version
4  *    Copyright IBM Corp. 1999
5  *    Author(s): Hartmut Penner (hp@de.ibm.com),
6  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
7  *
8  *  Derived from "include/asm-i386/processor.h"
9  *    Copyright (C) 1994, Linus Torvalds
10  */
11 
12 #ifndef __ASM_S390_PROCESSOR_H
13 #define __ASM_S390_PROCESSOR_H
14 
15 #include <linux/const.h>
16 
17 #define CIF_MCCK_PENDING	0	/* machine check handling is pending */
18 #define CIF_ASCE_PRIMARY	1	/* primary asce needs fixup / uaccess */
19 #define CIF_ASCE_SECONDARY	2	/* secondary asce needs fixup / uaccess */
20 #define CIF_NOHZ_DELAY		3	/* delay HZ disable for a tick */
21 #define CIF_FPU			4	/* restore FPU registers */
22 #define CIF_IGNORE_IRQ		5	/* ignore interrupt (for udelay) */
23 #define CIF_ENABLED_WAIT	6	/* in enabled wait state */
24 #define CIF_MCCK_GUEST		7	/* machine check happening in guest */
25 #define CIF_DEDICATED_CPU	8	/* this CPU is dedicated */
26 
27 #define _CIF_MCCK_PENDING	_BITUL(CIF_MCCK_PENDING)
28 #define _CIF_ASCE_PRIMARY	_BITUL(CIF_ASCE_PRIMARY)
29 #define _CIF_ASCE_SECONDARY	_BITUL(CIF_ASCE_SECONDARY)
30 #define _CIF_NOHZ_DELAY		_BITUL(CIF_NOHZ_DELAY)
31 #define _CIF_FPU		_BITUL(CIF_FPU)
32 #define _CIF_IGNORE_IRQ		_BITUL(CIF_IGNORE_IRQ)
33 #define _CIF_ENABLED_WAIT	_BITUL(CIF_ENABLED_WAIT)
34 #define _CIF_MCCK_GUEST		_BITUL(CIF_MCCK_GUEST)
35 #define _CIF_DEDICATED_CPU	_BITUL(CIF_DEDICATED_CPU)
36 
37 #ifndef __ASSEMBLY__
38 
39 #include <linux/linkage.h>
40 #include <linux/irqflags.h>
41 #include <asm/cpu.h>
42 #include <asm/page.h>
43 #include <asm/ptrace.h>
44 #include <asm/setup.h>
45 #include <asm/runtime_instr.h>
46 #include <asm/fpu/types.h>
47 #include <asm/fpu/internal.h>
48 
49 static inline void set_cpu_flag(int flag)
50 {
51 	S390_lowcore.cpu_flags |= (1UL << flag);
52 }
53 
54 static inline void clear_cpu_flag(int flag)
55 {
56 	S390_lowcore.cpu_flags &= ~(1UL << flag);
57 }
58 
59 static inline int test_cpu_flag(int flag)
60 {
61 	return !!(S390_lowcore.cpu_flags & (1UL << flag));
62 }
63 
64 /*
65  * Test CIF flag of another CPU. The caller needs to ensure that
66  * CPU hotplug can not happen, e.g. by disabling preemption.
67  */
68 static inline int test_cpu_flag_of(int flag, int cpu)
69 {
70 	struct lowcore *lc = lowcore_ptr[cpu];
71 	return !!(lc->cpu_flags & (1UL << flag));
72 }
73 
74 #define arch_needs_cpu() test_cpu_flag(CIF_NOHZ_DELAY)
75 
76 /*
77  * Default implementation of macro that returns current
78  * instruction pointer ("program counter").
79  */
80 #define current_text_addr() ({ void *pc; asm("basr %0,0" : "=a" (pc)); pc; })
81 
82 static inline void get_cpu_id(struct cpuid *ptr)
83 {
84 	asm volatile("stidp %0" : "=Q" (*ptr));
85 }
86 
87 void s390_adjust_jiffies(void);
88 void s390_update_cpu_mhz(void);
89 void cpu_detect_mhz_feature(void);
90 
91 extern const struct seq_operations cpuinfo_op;
92 extern int sysctl_ieee_emulation_warnings;
93 extern void execve_tail(void);
94 extern void __bpon(void);
95 
96 /*
97  * User space process size: 2GB for 31 bit, 4TB or 8PT for 64 bit.
98  */
99 
100 #define TASK_SIZE_OF(tsk)	(test_tsk_thread_flag(tsk, TIF_31BIT) ? \
101 					(1UL << 31) : -PAGE_SIZE)
102 #define TASK_UNMAPPED_BASE	(test_thread_flag(TIF_31BIT) ? \
103 					(1UL << 30) : (1UL << 41))
104 #define TASK_SIZE		TASK_SIZE_OF(current)
105 #define TASK_SIZE_MAX		(-PAGE_SIZE)
106 
107 #define STACK_TOP		(test_thread_flag(TIF_31BIT) ? \
108 					(1UL << 31) : (1UL << 42))
109 #define STACK_TOP_MAX		(1UL << 42)
110 
111 #define HAVE_ARCH_PICK_MMAP_LAYOUT
112 
113 typedef unsigned int mm_segment_t;
114 
115 /*
116  * Thread structure
117  */
118 struct thread_struct {
119 	unsigned int  acrs[NUM_ACRS];
120         unsigned long ksp;              /* kernel stack pointer             */
121 	unsigned long user_timer;	/* task cputime in user space */
122 	unsigned long guest_timer;	/* task cputime in kvm guest */
123 	unsigned long system_timer;	/* task cputime in kernel space */
124 	unsigned long hardirq_timer;	/* task cputime in hardirq context */
125 	unsigned long softirq_timer;	/* task cputime in softirq context */
126 	unsigned long sys_call_table;	/* system call table address */
127 	mm_segment_t mm_segment;
128 	unsigned long gmap_addr;	/* address of last gmap fault. */
129 	unsigned int gmap_write_flag;	/* gmap fault write indication */
130 	unsigned int gmap_int_code;	/* int code of last gmap fault */
131 	unsigned int gmap_pfault;	/* signal of a pending guest pfault */
132 	/* Per-thread information related to debugging */
133 	struct per_regs per_user;	/* User specified PER registers */
134 	struct per_event per_event;	/* Cause of the last PER trap */
135 	unsigned long per_flags;	/* Flags to control debug behavior */
136 	unsigned int system_call;	/* system call number in signal */
137 	unsigned long last_break;	/* last breaking-event-address. */
138         /* pfault_wait is used to block the process on a pfault event */
139 	unsigned long pfault_wait;
140 	struct list_head list;
141 	/* cpu runtime instrumentation */
142 	struct runtime_instr_cb *ri_cb;
143 	struct gs_cb *gs_cb;		/* Current guarded storage cb */
144 	struct gs_cb *gs_bc_cb;		/* Broadcast guarded storage cb */
145 	unsigned char trap_tdb[256];	/* Transaction abort diagnose block */
146 	/*
147 	 * Warning: 'fpu' is dynamically-sized. It *MUST* be at
148 	 * the end.
149 	 */
150 	struct fpu fpu;			/* FP and VX register save area */
151 };
152 
153 /* Flag to disable transactions. */
154 #define PER_FLAG_NO_TE			1UL
155 /* Flag to enable random transaction aborts. */
156 #define PER_FLAG_TE_ABORT_RAND		2UL
157 /* Flag to specify random transaction abort mode:
158  * - abort each transaction at a random instruction before TEND if set.
159  * - abort random transactions at a random instruction if cleared.
160  */
161 #define PER_FLAG_TE_ABORT_RAND_TEND	4UL
162 
163 typedef struct thread_struct thread_struct;
164 
165 /*
166  * Stack layout of a C stack frame.
167  */
168 #ifndef __PACK_STACK
169 struct stack_frame {
170 	unsigned long back_chain;
171 	unsigned long empty1[5];
172 	unsigned long gprs[10];
173 	unsigned int  empty2[8];
174 };
175 #else
176 struct stack_frame {
177 	unsigned long empty1[5];
178 	unsigned int  empty2[8];
179 	unsigned long gprs[10];
180 	unsigned long back_chain;
181 };
182 #endif
183 
184 #define ARCH_MIN_TASKALIGN	8
185 
186 #define INIT_THREAD {							\
187 	.ksp = sizeof(init_stack) + (unsigned long) &init_stack,	\
188 	.fpu.regs = (void *) init_task.thread.fpu.fprs,			\
189 }
190 
191 /*
192  * Do necessary setup to start up a new thread.
193  */
194 #define start_thread(regs, new_psw, new_stackp) do {			\
195 	regs->psw.mask	= PSW_USER_BITS | PSW_MASK_EA | PSW_MASK_BA;	\
196 	regs->psw.addr	= new_psw;					\
197 	regs->gprs[15]	= new_stackp;					\
198 	execve_tail();							\
199 } while (0)
200 
201 #define start_thread31(regs, new_psw, new_stackp) do {			\
202 	regs->psw.mask	= PSW_USER_BITS | PSW_MASK_BA;			\
203 	regs->psw.addr	= new_psw;					\
204 	regs->gprs[15]	= new_stackp;					\
205 	crst_table_downgrade(current->mm);				\
206 	execve_tail();							\
207 } while (0)
208 
209 /* Forward declaration, a strange C thing */
210 struct task_struct;
211 struct mm_struct;
212 struct seq_file;
213 struct pt_regs;
214 
215 typedef int (*dump_trace_func_t)(void *data, unsigned long address, int reliable);
216 void dump_trace(dump_trace_func_t func, void *data,
217 		struct task_struct *task, unsigned long sp);
218 void show_registers(struct pt_regs *regs);
219 
220 void show_cacheinfo(struct seq_file *m);
221 
222 /* Free all resources held by a thread. */
223 static inline void release_thread(struct task_struct *tsk) { }
224 
225 /* Free guarded storage control block */
226 void guarded_storage_release(struct task_struct *tsk);
227 
228 unsigned long get_wchan(struct task_struct *p);
229 #define task_pt_regs(tsk) ((struct pt_regs *) \
230         (task_stack_page(tsk) + THREAD_SIZE) - 1)
231 #define KSTK_EIP(tsk)	(task_pt_regs(tsk)->psw.addr)
232 #define KSTK_ESP(tsk)	(task_pt_regs(tsk)->gprs[15])
233 
234 /* Has task runtime instrumentation enabled ? */
235 #define is_ri_task(tsk) (!!(tsk)->thread.ri_cb)
236 
237 static inline unsigned long current_stack_pointer(void)
238 {
239 	unsigned long sp;
240 
241 	asm volatile("la %0,0(15)" : "=a" (sp));
242 	return sp;
243 }
244 
245 static inline unsigned short stap(void)
246 {
247 	unsigned short cpu_address;
248 
249 	asm volatile("stap %0" : "=Q" (cpu_address));
250 	return cpu_address;
251 }
252 
253 /*
254  * Give up the time slice of the virtual PU.
255  */
256 #define cpu_relax_yield cpu_relax_yield
257 void cpu_relax_yield(void);
258 
259 #define cpu_relax() barrier()
260 
261 #define ECAG_CACHE_ATTRIBUTE	0
262 #define ECAG_CPU_ATTRIBUTE	1
263 
264 static inline unsigned long __ecag(unsigned int asi, unsigned char parm)
265 {
266 	unsigned long val;
267 
268 	asm volatile(".insn	rsy,0xeb000000004c,%0,0,0(%1)" /* ecag */
269 		     : "=d" (val) : "a" (asi << 8 | parm));
270 	return val;
271 }
272 
273 static inline void psw_set_key(unsigned int key)
274 {
275 	asm volatile("spka 0(%0)" : : "d" (key));
276 }
277 
278 /*
279  * Set PSW to specified value.
280  */
281 static inline void __load_psw(psw_t psw)
282 {
283 	asm volatile("lpswe %0" : : "Q" (psw) : "cc");
284 }
285 
286 /*
287  * Set PSW mask to specified value, while leaving the
288  * PSW addr pointing to the next instruction.
289  */
290 static inline void __load_psw_mask(unsigned long mask)
291 {
292 	unsigned long addr;
293 	psw_t psw;
294 
295 	psw.mask = mask;
296 
297 	asm volatile(
298 		"	larl	%0,1f\n"
299 		"	stg	%0,%O1+8(%R1)\n"
300 		"	lpswe	%1\n"
301 		"1:"
302 		: "=&d" (addr), "=Q" (psw) : "Q" (psw) : "memory", "cc");
303 }
304 
305 /*
306  * Extract current PSW mask
307  */
308 static inline unsigned long __extract_psw(void)
309 {
310 	unsigned int reg1, reg2;
311 
312 	asm volatile("epsw %0,%1" : "=d" (reg1), "=a" (reg2));
313 	return (((unsigned long) reg1) << 32) | ((unsigned long) reg2);
314 }
315 
316 static inline void local_mcck_enable(void)
317 {
318 	__load_psw_mask(__extract_psw() | PSW_MASK_MCHECK);
319 }
320 
321 static inline void local_mcck_disable(void)
322 {
323 	__load_psw_mask(__extract_psw() & ~PSW_MASK_MCHECK);
324 }
325 
326 /*
327  * Rewind PSW instruction address by specified number of bytes.
328  */
329 static inline unsigned long __rewind_psw(psw_t psw, unsigned long ilc)
330 {
331 	unsigned long mask;
332 
333 	mask = (psw.mask & PSW_MASK_EA) ? -1UL :
334 	       (psw.mask & PSW_MASK_BA) ? (1UL << 31) - 1 :
335 					  (1UL << 24) - 1;
336 	return (psw.addr - ilc) & mask;
337 }
338 
339 /*
340  * Function to stop a processor until the next interrupt occurs
341  */
342 void enabled_wait(void);
343 
344 /*
345  * Function to drop a processor into disabled wait state
346  */
347 static inline void __noreturn disabled_wait(unsigned long code)
348 {
349 	psw_t psw;
350 
351 	psw.mask = PSW_MASK_BASE | PSW_MASK_WAIT | PSW_MASK_BA | PSW_MASK_EA;
352 	psw.addr = code;
353 	__load_psw(psw);
354 	while (1);
355 }
356 
357 /*
358  * Basic Machine Check/Program Check Handler.
359  */
360 
361 extern void s390_base_mcck_handler(void);
362 extern void s390_base_pgm_handler(void);
363 extern void s390_base_ext_handler(void);
364 
365 extern void (*s390_base_mcck_handler_fn)(void);
366 extern void (*s390_base_pgm_handler_fn)(void);
367 extern void (*s390_base_ext_handler_fn)(void);
368 
369 #define ARCH_LOW_ADDRESS_LIMIT	0x7fffffffUL
370 
371 extern int memcpy_real(void *, void *, size_t);
372 extern void memcpy_absolute(void *, void *, size_t);
373 
374 #define mem_assign_absolute(dest, val) do {			\
375 	__typeof__(dest) __tmp = (val);				\
376 								\
377 	BUILD_BUG_ON(sizeof(__tmp) != sizeof(val));		\
378 	memcpy_absolute(&(dest), &__tmp, sizeof(__tmp));	\
379 } while (0)
380 
381 extern int s390_isolate_bp(void);
382 extern int s390_isolate_bp_guest(void);
383 
384 #endif /* __ASSEMBLY__ */
385 
386 #endif /* __ASM_S390_PROCESSOR_H */
387