xref: /openbmc/linux/arch/s390/include/asm/processor.h (revision 527d1470744d338c912f94bc1f4dba08ffdff349)
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 
95 /*
96  * User space process size: 2GB for 31 bit, 4TB or 8PT for 64 bit.
97  */
98 
99 #define TASK_SIZE_OF(tsk)	(test_tsk_thread_flag(tsk, TIF_31BIT) ? \
100 					(1UL << 31) : -PAGE_SIZE)
101 #define TASK_UNMAPPED_BASE	(test_thread_flag(TIF_31BIT) ? \
102 					(1UL << 30) : (1UL << 41))
103 #define TASK_SIZE		TASK_SIZE_OF(current)
104 #define TASK_SIZE_MAX		(-PAGE_SIZE)
105 
106 #define STACK_TOP		(test_thread_flag(TIF_31BIT) ? \
107 					(1UL << 31) : (1UL << 42))
108 #define STACK_TOP_MAX		(1UL << 42)
109 
110 #define HAVE_ARCH_PICK_MMAP_LAYOUT
111 
112 typedef struct {
113         __u32 ar4;
114 } mm_segment_t;
115 
116 /*
117  * Thread structure
118  */
119 struct thread_struct {
120 	unsigned int  acrs[NUM_ACRS];
121         unsigned long ksp;              /* kernel stack pointer             */
122 	unsigned long user_timer;	/* task cputime in user space */
123 	unsigned long guest_timer;	/* task cputime in kvm guest */
124 	unsigned long system_timer;	/* task cputime in kernel space */
125 	unsigned long hardirq_timer;	/* task cputime in hardirq context */
126 	unsigned long softirq_timer;	/* task cputime in softirq context */
127 	unsigned long sys_call_table;	/* system call table address */
128 	mm_segment_t mm_segment;
129 	unsigned long gmap_addr;	/* address of last gmap fault. */
130 	unsigned int gmap_write_flag;	/* gmap fault write indication */
131 	unsigned int gmap_int_code;	/* int code of last gmap fault */
132 	unsigned int gmap_pfault;	/* signal of a pending guest pfault */
133 	/* Per-thread information related to debugging */
134 	struct per_regs per_user;	/* User specified PER registers */
135 	struct per_event per_event;	/* Cause of the last PER trap */
136 	unsigned long per_flags;	/* Flags to control debug behavior */
137 	unsigned int system_call;	/* system call number in signal */
138 	unsigned long last_break;	/* last breaking-event-address. */
139         /* pfault_wait is used to block the process on a pfault event */
140 	unsigned long pfault_wait;
141 	struct list_head list;
142 	/* cpu runtime instrumentation */
143 	struct runtime_instr_cb *ri_cb;
144 	struct gs_cb *gs_cb;		/* Current guarded storage cb */
145 	struct gs_cb *gs_bc_cb;		/* Broadcast guarded storage cb */
146 	unsigned char trap_tdb[256];	/* Transaction abort diagnose block */
147 	/*
148 	 * Warning: 'fpu' is dynamically-sized. It *MUST* be at
149 	 * the end.
150 	 */
151 	struct fpu fpu;			/* FP and VX register save area */
152 };
153 
154 /* Flag to disable transactions. */
155 #define PER_FLAG_NO_TE			1UL
156 /* Flag to enable random transaction aborts. */
157 #define PER_FLAG_TE_ABORT_RAND		2UL
158 /* Flag to specify random transaction abort mode:
159  * - abort each transaction at a random instruction before TEND if set.
160  * - abort random transactions at a random instruction if cleared.
161  */
162 #define PER_FLAG_TE_ABORT_RAND_TEND	4UL
163 
164 typedef struct thread_struct thread_struct;
165 
166 /*
167  * Stack layout of a C stack frame.
168  */
169 #ifndef __PACK_STACK
170 struct stack_frame {
171 	unsigned long back_chain;
172 	unsigned long empty1[5];
173 	unsigned long gprs[10];
174 	unsigned int  empty2[8];
175 };
176 #else
177 struct stack_frame {
178 	unsigned long empty1[5];
179 	unsigned int  empty2[8];
180 	unsigned long gprs[10];
181 	unsigned long back_chain;
182 };
183 #endif
184 
185 #define ARCH_MIN_TASKALIGN	8
186 
187 #define INIT_THREAD {							\
188 	.ksp = sizeof(init_stack) + (unsigned long) &init_stack,	\
189 	.fpu.regs = (void *) init_task.thread.fpu.fprs,			\
190 }
191 
192 /*
193  * Do necessary setup to start up a new thread.
194  */
195 #define start_thread(regs, new_psw, new_stackp) do {			\
196 	regs->psw.mask	= PSW_USER_BITS | PSW_MASK_EA | PSW_MASK_BA;	\
197 	regs->psw.addr	= new_psw;					\
198 	regs->gprs[15]	= new_stackp;					\
199 	execve_tail();							\
200 } while (0)
201 
202 #define start_thread31(regs, new_psw, new_stackp) do {			\
203 	regs->psw.mask	= PSW_USER_BITS | PSW_MASK_BA;			\
204 	regs->psw.addr	= new_psw;					\
205 	regs->gprs[15]	= new_stackp;					\
206 	crst_table_downgrade(current->mm);				\
207 	execve_tail();							\
208 } while (0)
209 
210 /* Forward declaration, a strange C thing */
211 struct task_struct;
212 struct mm_struct;
213 struct seq_file;
214 struct pt_regs;
215 
216 typedef int (*dump_trace_func_t)(void *data, unsigned long address, int reliable);
217 void dump_trace(dump_trace_func_t func, void *data,
218 		struct task_struct *task, unsigned long sp);
219 void show_registers(struct pt_regs *regs);
220 
221 void show_cacheinfo(struct seq_file *m);
222 
223 /* Free all resources held by a thread. */
224 static inline void release_thread(struct task_struct *tsk) { }
225 
226 /* Free guarded storage control block */
227 void guarded_storage_release(struct task_struct *tsk);
228 
229 unsigned long get_wchan(struct task_struct *p);
230 #define task_pt_regs(tsk) ((struct pt_regs *) \
231         (task_stack_page(tsk) + THREAD_SIZE) - 1)
232 #define KSTK_EIP(tsk)	(task_pt_regs(tsk)->psw.addr)
233 #define KSTK_ESP(tsk)	(task_pt_regs(tsk)->gprs[15])
234 
235 /* Has task runtime instrumentation enabled ? */
236 #define is_ri_task(tsk) (!!(tsk)->thread.ri_cb)
237 
238 static inline unsigned long current_stack_pointer(void)
239 {
240 	unsigned long sp;
241 
242 	asm volatile("la %0,0(15)" : "=a" (sp));
243 	return sp;
244 }
245 
246 static inline unsigned short stap(void)
247 {
248 	unsigned short cpu_address;
249 
250 	asm volatile("stap %0" : "=m" (cpu_address));
251 	return cpu_address;
252 }
253 
254 /*
255  * Give up the time slice of the virtual PU.
256  */
257 #define cpu_relax_yield cpu_relax_yield
258 void cpu_relax_yield(void);
259 
260 #define cpu_relax() barrier()
261 
262 #define ECAG_CACHE_ATTRIBUTE	0
263 #define ECAG_CPU_ATTRIBUTE	1
264 
265 static inline unsigned long __ecag(unsigned int asi, unsigned char parm)
266 {
267 	unsigned long val;
268 
269 	asm volatile(".insn	rsy,0xeb000000004c,%0,0,0(%1)" /* ecag */
270 		     : "=d" (val) : "a" (asi << 8 | parm));
271 	return val;
272 }
273 
274 static inline void psw_set_key(unsigned int key)
275 {
276 	asm volatile("spka 0(%0)" : : "d" (key));
277 }
278 
279 /*
280  * Set PSW to specified value.
281  */
282 static inline void __load_psw(psw_t psw)
283 {
284 	asm volatile("lpswe %0" : : "Q" (psw) : "cc");
285 }
286 
287 /*
288  * Set PSW mask to specified value, while leaving the
289  * PSW addr pointing to the next instruction.
290  */
291 static inline void __load_psw_mask(unsigned long mask)
292 {
293 	unsigned long addr;
294 	psw_t psw;
295 
296 	psw.mask = mask;
297 
298 	asm volatile(
299 		"	larl	%0,1f\n"
300 		"	stg	%0,%O1+8(%R1)\n"
301 		"	lpswe	%1\n"
302 		"1:"
303 		: "=&d" (addr), "=Q" (psw) : "Q" (psw) : "memory", "cc");
304 }
305 
306 /*
307  * Extract current PSW mask
308  */
309 static inline unsigned long __extract_psw(void)
310 {
311 	unsigned int reg1, reg2;
312 
313 	asm volatile("epsw %0,%1" : "=d" (reg1), "=a" (reg2));
314 	return (((unsigned long) reg1) << 32) | ((unsigned long) reg2);
315 }
316 
317 static inline void local_mcck_enable(void)
318 {
319 	__load_psw_mask(__extract_psw() | PSW_MASK_MCHECK);
320 }
321 
322 static inline void local_mcck_disable(void)
323 {
324 	__load_psw_mask(__extract_psw() & ~PSW_MASK_MCHECK);
325 }
326 
327 /*
328  * Rewind PSW instruction address by specified number of bytes.
329  */
330 static inline unsigned long __rewind_psw(psw_t psw, unsigned long ilc)
331 {
332 	unsigned long mask;
333 
334 	mask = (psw.mask & PSW_MASK_EA) ? -1UL :
335 	       (psw.mask & PSW_MASK_BA) ? (1UL << 31) - 1 :
336 					  (1UL << 24) - 1;
337 	return (psw.addr - ilc) & mask;
338 }
339 
340 /*
341  * Function to stop a processor until the next interrupt occurs
342  */
343 void enabled_wait(void);
344 
345 /*
346  * Function to drop a processor into disabled wait state
347  */
348 static inline void __noreturn disabled_wait(unsigned long code)
349 {
350 	psw_t psw;
351 
352 	psw.mask = PSW_MASK_BASE | PSW_MASK_WAIT | PSW_MASK_BA | PSW_MASK_EA;
353 	psw.addr = code;
354 	__load_psw(psw);
355 	while (1);
356 }
357 
358 /*
359  * Basic Machine Check/Program Check Handler.
360  */
361 
362 extern void s390_base_mcck_handler(void);
363 extern void s390_base_pgm_handler(void);
364 extern void s390_base_ext_handler(void);
365 
366 extern void (*s390_base_mcck_handler_fn)(void);
367 extern void (*s390_base_pgm_handler_fn)(void);
368 extern void (*s390_base_ext_handler_fn)(void);
369 
370 #define ARCH_LOW_ADDRESS_LIMIT	0x7fffffffUL
371 
372 extern int memcpy_real(void *, void *, size_t);
373 extern void memcpy_absolute(void *, void *, size_t);
374 
375 #define mem_assign_absolute(dest, val) do {			\
376 	__typeof__(dest) __tmp = (val);				\
377 								\
378 	BUILD_BUG_ON(sizeof(__tmp) != sizeof(val));		\
379 	memcpy_absolute(&(dest), &__tmp, sizeof(__tmp));	\
380 } while (0)
381 
382 #endif /* __ASSEMBLY__ */
383 
384 #endif /* __ASM_S390_PROCESSOR_H */
385