xref: /linux/arch/s390/include/asm/processor.h (revision d195c39052d1da278a00a6744ce59c383b67b191)
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/bits.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	BIT(CIF_MCCK_PENDING)
28 #define _CIF_ASCE_PRIMARY	BIT(CIF_ASCE_PRIMARY)
29 #define _CIF_ASCE_SECONDARY	BIT(CIF_ASCE_SECONDARY)
30 #define _CIF_NOHZ_DELAY		BIT(CIF_NOHZ_DELAY)
31 #define _CIF_FPU		BIT(CIF_FPU)
32 #define _CIF_IGNORE_IRQ		BIT(CIF_IGNORE_IRQ)
33 #define _CIF_ENABLED_WAIT	BIT(CIF_ENABLED_WAIT)
34 #define _CIF_MCCK_GUEST		BIT(CIF_MCCK_GUEST)
35 #define _CIF_DEDICATED_CPU	BIT(CIF_DEDICATED_CPU)
36 
37 #ifndef __ASSEMBLY__
38 
39 #include <linux/cpumask.h>
40 #include <linux/linkage.h>
41 #include <linux/irqflags.h>
42 #include <asm/cpu.h>
43 #include <asm/page.h>
44 #include <asm/ptrace.h>
45 #include <asm/setup.h>
46 #include <asm/runtime_instr.h>
47 #include <asm/fpu/types.h>
48 #include <asm/fpu/internal.h>
49 
50 static inline void set_cpu_flag(int flag)
51 {
52 	S390_lowcore.cpu_flags |= (1UL << flag);
53 }
54 
55 static inline void clear_cpu_flag(int flag)
56 {
57 	S390_lowcore.cpu_flags &= ~(1UL << flag);
58 }
59 
60 static inline int test_cpu_flag(int flag)
61 {
62 	return !!(S390_lowcore.cpu_flags & (1UL << flag));
63 }
64 
65 /*
66  * Test CIF flag of another CPU. The caller needs to ensure that
67  * CPU hotplug can not happen, e.g. by disabling preemption.
68  */
69 static inline int test_cpu_flag_of(int flag, int cpu)
70 {
71 	struct lowcore *lc = lowcore_ptr[cpu];
72 	return !!(lc->cpu_flags & (1UL << flag));
73 }
74 
75 #define arch_needs_cpu() test_cpu_flag(CIF_NOHZ_DELAY)
76 
77 static inline void get_cpu_id(struct cpuid *ptr)
78 {
79 	asm volatile("stidp %0" : "=Q" (*ptr));
80 }
81 
82 void s390_adjust_jiffies(void);
83 void s390_update_cpu_mhz(void);
84 void cpu_detect_mhz_feature(void);
85 
86 extern const struct seq_operations cpuinfo_op;
87 extern void execve_tail(void);
88 extern void __bpon(void);
89 
90 /*
91  * User space process size: 2GB for 31 bit, 4TB or 8PT for 64 bit.
92  */
93 
94 #define TASK_SIZE_OF(tsk)	(test_tsk_thread_flag(tsk, TIF_31BIT) ? \
95 					_REGION3_SIZE : TASK_SIZE_MAX)
96 #define TASK_UNMAPPED_BASE	(test_thread_flag(TIF_31BIT) ? \
97 					(_REGION3_SIZE >> 1) : (_REGION2_SIZE >> 1))
98 #define TASK_SIZE		TASK_SIZE_OF(current)
99 #define TASK_SIZE_MAX		(-PAGE_SIZE)
100 
101 #define STACK_TOP		(test_thread_flag(TIF_31BIT) ? \
102 					_REGION3_SIZE : _REGION2_SIZE)
103 #define STACK_TOP_MAX		_REGION2_SIZE
104 
105 #define HAVE_ARCH_PICK_MMAP_LAYOUT
106 
107 typedef unsigned int mm_segment_t;
108 
109 /*
110  * Thread structure
111  */
112 struct thread_struct {
113 	unsigned int  acrs[NUM_ACRS];
114         unsigned long ksp;              /* kernel stack pointer             */
115 	unsigned long user_timer;	/* task cputime in user space */
116 	unsigned long guest_timer;	/* task cputime in kvm guest */
117 	unsigned long system_timer;	/* task cputime in kernel space */
118 	unsigned long hardirq_timer;	/* task cputime in hardirq context */
119 	unsigned long softirq_timer;	/* task cputime in softirq context */
120 	unsigned long sys_call_table;	/* system call table address */
121 	mm_segment_t mm_segment;
122 	unsigned long gmap_addr;	/* address of last gmap fault. */
123 	unsigned int gmap_write_flag;	/* gmap fault write indication */
124 	unsigned int gmap_int_code;	/* int code of last gmap fault */
125 	unsigned int gmap_pfault;	/* signal of a pending guest pfault */
126 	/* Per-thread information related to debugging */
127 	struct per_regs per_user;	/* User specified PER registers */
128 	struct per_event per_event;	/* Cause of the last PER trap */
129 	unsigned long per_flags;	/* Flags to control debug behavior */
130 	unsigned int system_call;	/* system call number in signal */
131 	unsigned long last_break;	/* last breaking-event-address. */
132         /* pfault_wait is used to block the process on a pfault event */
133 	unsigned long pfault_wait;
134 	struct list_head list;
135 	/* cpu runtime instrumentation */
136 	struct runtime_instr_cb *ri_cb;
137 	struct gs_cb *gs_cb;		/* Current guarded storage cb */
138 	struct gs_cb *gs_bc_cb;		/* Broadcast guarded storage cb */
139 	unsigned char trap_tdb[256];	/* Transaction abort diagnose block */
140 	/*
141 	 * Warning: 'fpu' is dynamically-sized. It *MUST* be at
142 	 * the end.
143 	 */
144 	struct fpu fpu;			/* FP and VX register save area */
145 };
146 
147 /* Flag to disable transactions. */
148 #define PER_FLAG_NO_TE			1UL
149 /* Flag to enable random transaction aborts. */
150 #define PER_FLAG_TE_ABORT_RAND		2UL
151 /* Flag to specify random transaction abort mode:
152  * - abort each transaction at a random instruction before TEND if set.
153  * - abort random transactions at a random instruction if cleared.
154  */
155 #define PER_FLAG_TE_ABORT_RAND_TEND	4UL
156 
157 typedef struct thread_struct thread_struct;
158 
159 #define ARCH_MIN_TASKALIGN	8
160 
161 #define INIT_THREAD {							\
162 	.ksp = sizeof(init_stack) + (unsigned long) &init_stack,	\
163 	.fpu.regs = (void *) init_task.thread.fpu.fprs,			\
164 	.last_break = 1,						\
165 }
166 
167 /*
168  * Do necessary setup to start up a new thread.
169  */
170 #define start_thread(regs, new_psw, new_stackp) do {			\
171 	regs->psw.mask	= PSW_USER_BITS | PSW_MASK_EA | PSW_MASK_BA;	\
172 	regs->psw.addr	= new_psw;					\
173 	regs->gprs[15]	= new_stackp;					\
174 	execve_tail();							\
175 } while (0)
176 
177 #define start_thread31(regs, new_psw, new_stackp) do {			\
178 	regs->psw.mask	= PSW_USER_BITS | PSW_MASK_BA;			\
179 	regs->psw.addr	= new_psw;					\
180 	regs->gprs[15]	= new_stackp;					\
181 	execve_tail();							\
182 } while (0)
183 
184 /* Forward declaration, a strange C thing */
185 struct task_struct;
186 struct mm_struct;
187 struct seq_file;
188 struct pt_regs;
189 
190 void show_registers(struct pt_regs *regs);
191 void show_cacheinfo(struct seq_file *m);
192 
193 /* Free all resources held by a thread. */
194 static inline void release_thread(struct task_struct *tsk) { }
195 
196 /* Free guarded storage control block */
197 void guarded_storage_release(struct task_struct *tsk);
198 
199 unsigned long get_wchan(struct task_struct *p);
200 #define task_pt_regs(tsk) ((struct pt_regs *) \
201         (task_stack_page(tsk) + THREAD_SIZE) - 1)
202 #define KSTK_EIP(tsk)	(task_pt_regs(tsk)->psw.addr)
203 #define KSTK_ESP(tsk)	(task_pt_regs(tsk)->gprs[15])
204 
205 /* Has task runtime instrumentation enabled ? */
206 #define is_ri_task(tsk) (!!(tsk)->thread.ri_cb)
207 
208 static __always_inline unsigned long current_stack_pointer(void)
209 {
210 	unsigned long sp;
211 
212 	asm volatile("la %0,0(15)" : "=a" (sp));
213 	return sp;
214 }
215 
216 static __no_kasan_or_inline unsigned short stap(void)
217 {
218 	unsigned short cpu_address;
219 
220 	asm volatile("stap %0" : "=Q" (cpu_address));
221 	return cpu_address;
222 }
223 
224 #define cpu_relax() barrier()
225 
226 #define ECAG_CACHE_ATTRIBUTE	0
227 #define ECAG_CPU_ATTRIBUTE	1
228 
229 static inline unsigned long __ecag(unsigned int asi, unsigned char parm)
230 {
231 	unsigned long val;
232 
233 	asm volatile(".insn	rsy,0xeb000000004c,%0,0,0(%1)" /* ecag */
234 		     : "=d" (val) : "a" (asi << 8 | parm));
235 	return val;
236 }
237 
238 static inline void psw_set_key(unsigned int key)
239 {
240 	asm volatile("spka 0(%0)" : : "d" (key));
241 }
242 
243 /*
244  * Set PSW to specified value.
245  */
246 static inline void __load_psw(psw_t psw)
247 {
248 	asm volatile("lpswe %0" : : "Q" (psw) : "cc");
249 }
250 
251 /*
252  * Set PSW mask to specified value, while leaving the
253  * PSW addr pointing to the next instruction.
254  */
255 static __no_kasan_or_inline void __load_psw_mask(unsigned long mask)
256 {
257 	unsigned long addr;
258 	psw_t psw;
259 
260 	psw.mask = mask;
261 
262 	asm volatile(
263 		"	larl	%0,1f\n"
264 		"	stg	%0,%1\n"
265 		"	lpswe	%2\n"
266 		"1:"
267 		: "=&d" (addr), "=Q" (psw.addr) : "Q" (psw) : "memory", "cc");
268 }
269 
270 /*
271  * Extract current PSW mask
272  */
273 static inline unsigned long __extract_psw(void)
274 {
275 	unsigned int reg1, reg2;
276 
277 	asm volatile("epsw %0,%1" : "=d" (reg1), "=a" (reg2));
278 	return (((unsigned long) reg1) << 32) | ((unsigned long) reg2);
279 }
280 
281 static inline void local_mcck_enable(void)
282 {
283 	__load_psw_mask(__extract_psw() | PSW_MASK_MCHECK);
284 }
285 
286 static inline void local_mcck_disable(void)
287 {
288 	__load_psw_mask(__extract_psw() & ~PSW_MASK_MCHECK);
289 }
290 
291 /*
292  * Rewind PSW instruction address by specified number of bytes.
293  */
294 static inline unsigned long __rewind_psw(psw_t psw, unsigned long ilc)
295 {
296 	unsigned long mask;
297 
298 	mask = (psw.mask & PSW_MASK_EA) ? -1UL :
299 	       (psw.mask & PSW_MASK_BA) ? (1UL << 31) - 1 :
300 					  (1UL << 24) - 1;
301 	return (psw.addr - ilc) & mask;
302 }
303 
304 /*
305  * Function to stop a processor until the next interrupt occurs
306  */
307 void enabled_wait(void);
308 
309 /*
310  * Function to drop a processor into disabled wait state
311  */
312 static __always_inline void __noreturn disabled_wait(void)
313 {
314 	psw_t psw;
315 
316 	psw.mask = PSW_MASK_BASE | PSW_MASK_WAIT | PSW_MASK_BA | PSW_MASK_EA;
317 	psw.addr = _THIS_IP_;
318 	__load_psw(psw);
319 	while (1);
320 }
321 
322 /*
323  * Basic Machine Check/Program Check Handler.
324  */
325 
326 extern void s390_base_pgm_handler(void);
327 extern void s390_base_ext_handler(void);
328 
329 extern void (*s390_base_pgm_handler_fn)(void);
330 extern void (*s390_base_ext_handler_fn)(void);
331 
332 #define ARCH_LOW_ADDRESS_LIMIT	0x7fffffffUL
333 
334 extern int memcpy_real(void *, void *, size_t);
335 extern void memcpy_absolute(void *, void *, size_t);
336 
337 #define mem_assign_absolute(dest, val) do {			\
338 	__typeof__(dest) __tmp = (val);				\
339 								\
340 	BUILD_BUG_ON(sizeof(__tmp) != sizeof(val));		\
341 	memcpy_absolute(&(dest), &__tmp, sizeof(__tmp));	\
342 } while (0)
343 
344 extern int s390_isolate_bp(void);
345 extern int s390_isolate_bp_guest(void);
346 
347 #endif /* __ASSEMBLY__ */
348 
349 #endif /* __ASM_S390_PROCESSOR_H */
350