xref: /openbmc/linux/arch/s390/include/asm/processor.h (revision e15a5365)
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_ASCE_PRIMARY	0	/* primary asce needs fixup / uaccess */
18 #define CIF_ASCE_SECONDARY	1	/* secondary asce needs fixup / uaccess */
19 #define CIF_NOHZ_DELAY		2	/* delay HZ disable for a tick */
20 #define CIF_FPU			3	/* restore FPU registers */
21 #define CIF_IGNORE_IRQ		4	/* ignore interrupt (for udelay) */
22 #define CIF_ENABLED_WAIT	5	/* in enabled wait state */
23 #define CIF_MCCK_GUEST		6	/* machine check happening in guest */
24 #define CIF_DEDICATED_CPU	7	/* this CPU is dedicated */
25 
26 #define _CIF_ASCE_PRIMARY	BIT(CIF_ASCE_PRIMARY)
27 #define _CIF_ASCE_SECONDARY	BIT(CIF_ASCE_SECONDARY)
28 #define _CIF_NOHZ_DELAY		BIT(CIF_NOHZ_DELAY)
29 #define _CIF_FPU		BIT(CIF_FPU)
30 #define _CIF_IGNORE_IRQ		BIT(CIF_IGNORE_IRQ)
31 #define _CIF_ENABLED_WAIT	BIT(CIF_ENABLED_WAIT)
32 #define _CIF_MCCK_GUEST		BIT(CIF_MCCK_GUEST)
33 #define _CIF_DEDICATED_CPU	BIT(CIF_DEDICATED_CPU)
34 
35 #ifndef __ASSEMBLY__
36 
37 #include <linux/cpumask.h>
38 #include <linux/linkage.h>
39 #include <linux/irqflags.h>
40 #include <asm/cpu.h>
41 #include <asm/page.h>
42 #include <asm/ptrace.h>
43 #include <asm/setup.h>
44 #include <asm/runtime_instr.h>
45 #include <asm/fpu/types.h>
46 #include <asm/fpu/internal.h>
47 
48 static inline void set_cpu_flag(int flag)
49 {
50 	S390_lowcore.cpu_flags |= (1UL << flag);
51 }
52 
53 static inline void clear_cpu_flag(int flag)
54 {
55 	S390_lowcore.cpu_flags &= ~(1UL << flag);
56 }
57 
58 static inline int test_cpu_flag(int flag)
59 {
60 	return !!(S390_lowcore.cpu_flags & (1UL << flag));
61 }
62 
63 /*
64  * Test CIF flag of another CPU. The caller needs to ensure that
65  * CPU hotplug can not happen, e.g. by disabling preemption.
66  */
67 static inline int test_cpu_flag_of(int flag, int cpu)
68 {
69 	struct lowcore *lc = lowcore_ptr[cpu];
70 	return !!(lc->cpu_flags & (1UL << flag));
71 }
72 
73 #define arch_needs_cpu() test_cpu_flag(CIF_NOHZ_DELAY)
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 void execve_tail(void);
86 extern void __bpon(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)	(test_tsk_thread_flag(tsk, TIF_31BIT) ? \
93 					_REGION3_SIZE : TASK_SIZE_MAX)
94 #define TASK_UNMAPPED_BASE	(test_thread_flag(TIF_31BIT) ? \
95 					(_REGION3_SIZE >> 1) : (_REGION2_SIZE >> 1))
96 #define TASK_SIZE		TASK_SIZE_OF(current)
97 #define TASK_SIZE_MAX		(-PAGE_SIZE)
98 
99 #define STACK_TOP		(test_thread_flag(TIF_31BIT) ? \
100 					_REGION3_SIZE : _REGION2_SIZE)
101 #define STACK_TOP_MAX		_REGION2_SIZE
102 
103 #define HAVE_ARCH_PICK_MMAP_LAYOUT
104 
105 typedef unsigned int 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 guest_timer;	/* task cputime in kvm guest */
115 	unsigned long system_timer;	/* task cputime in kernel space */
116 	unsigned long hardirq_timer;	/* task cputime in hardirq context */
117 	unsigned long softirq_timer;	/* task cputime in softirq context */
118 	unsigned long sys_call_table;	/* system call table address */
119 	mm_segment_t mm_segment;
120 	unsigned long gmap_addr;	/* address of last gmap fault. */
121 	unsigned int gmap_write_flag;	/* gmap fault write indication */
122 	unsigned int gmap_int_code;	/* int code of last gmap fault */
123 	unsigned int gmap_pfault;	/* signal of a pending guest pfault */
124 	/* Per-thread information related to debugging */
125 	struct per_regs per_user;	/* User specified PER registers */
126 	struct per_event per_event;	/* Cause of the last PER trap */
127 	unsigned long per_flags;	/* Flags to control debug behavior */
128 	unsigned int system_call;	/* system call number in signal */
129 	unsigned long last_break;	/* last breaking-event-address. */
130         /* pfault_wait is used to block the process on a pfault event */
131 	unsigned long pfault_wait;
132 	struct list_head list;
133 	/* cpu runtime instrumentation */
134 	struct runtime_instr_cb *ri_cb;
135 	struct gs_cb *gs_cb;		/* Current guarded storage cb */
136 	struct gs_cb *gs_bc_cb;		/* Broadcast guarded storage cb */
137 	unsigned char trap_tdb[256];	/* Transaction abort diagnose block */
138 	/*
139 	 * Warning: 'fpu' is dynamically-sized. It *MUST* be at
140 	 * the end.
141 	 */
142 	struct fpu fpu;			/* FP and VX register save area */
143 };
144 
145 /* Flag to disable transactions. */
146 #define PER_FLAG_NO_TE			1UL
147 /* Flag to enable random transaction aborts. */
148 #define PER_FLAG_TE_ABORT_RAND		2UL
149 /* Flag to specify random transaction abort mode:
150  * - abort each transaction at a random instruction before TEND if set.
151  * - abort random transactions at a random instruction if cleared.
152  */
153 #define PER_FLAG_TE_ABORT_RAND_TEND	4UL
154 
155 typedef struct thread_struct thread_struct;
156 
157 #define ARCH_MIN_TASKALIGN	8
158 
159 #define INIT_THREAD {							\
160 	.ksp = sizeof(init_stack) + (unsigned long) &init_stack,	\
161 	.fpu.regs = (void *) init_task.thread.fpu.fprs,			\
162 	.last_break = 1,						\
163 }
164 
165 /*
166  * Do necessary setup to start up a new thread.
167  */
168 #define start_thread(regs, new_psw, new_stackp) do {			\
169 	regs->psw.mask	= PSW_USER_BITS | PSW_MASK_EA | PSW_MASK_BA;	\
170 	regs->psw.addr	= new_psw;					\
171 	regs->gprs[15]	= new_stackp;					\
172 	execve_tail();							\
173 } while (0)
174 
175 #define start_thread31(regs, new_psw, new_stackp) do {			\
176 	regs->psw.mask	= PSW_USER_BITS | PSW_MASK_BA;			\
177 	regs->psw.addr	= new_psw;					\
178 	regs->gprs[15]	= new_stackp;					\
179 	execve_tail();							\
180 } while (0)
181 
182 /* Forward declaration, a strange C thing */
183 struct task_struct;
184 struct mm_struct;
185 struct seq_file;
186 struct pt_regs;
187 
188 void show_registers(struct pt_regs *regs);
189 void show_cacheinfo(struct seq_file *m);
190 
191 /* Free all resources held by a thread. */
192 static inline void release_thread(struct task_struct *tsk) { }
193 
194 /* Free guarded storage control block */
195 void guarded_storage_release(struct task_struct *tsk);
196 
197 unsigned long get_wchan(struct task_struct *p);
198 #define task_pt_regs(tsk) ((struct pt_regs *) \
199         (task_stack_page(tsk) + THREAD_SIZE) - 1)
200 #define KSTK_EIP(tsk)	(task_pt_regs(tsk)->psw.addr)
201 #define KSTK_ESP(tsk)	(task_pt_regs(tsk)->gprs[15])
202 
203 /* Has task runtime instrumentation enabled ? */
204 #define is_ri_task(tsk) (!!(tsk)->thread.ri_cb)
205 
206 static __always_inline unsigned long current_stack_pointer(void)
207 {
208 	unsigned long sp;
209 
210 	asm volatile("la %0,0(15)" : "=a" (sp));
211 	return sp;
212 }
213 
214 static __no_kasan_or_inline unsigned short stap(void)
215 {
216 	unsigned short cpu_address;
217 
218 	asm volatile("stap %0" : "=Q" (cpu_address));
219 	return cpu_address;
220 }
221 
222 #define cpu_relax() barrier()
223 
224 #define ECAG_CACHE_ATTRIBUTE	0
225 #define ECAG_CPU_ATTRIBUTE	1
226 
227 static inline unsigned long __ecag(unsigned int asi, unsigned char parm)
228 {
229 	unsigned long val;
230 
231 	asm volatile(".insn	rsy,0xeb000000004c,%0,0,0(%1)" /* ecag */
232 		     : "=d" (val) : "a" (asi << 8 | parm));
233 	return val;
234 }
235 
236 static inline void psw_set_key(unsigned int key)
237 {
238 	asm volatile("spka 0(%0)" : : "d" (key));
239 }
240 
241 /*
242  * Set PSW to specified value.
243  */
244 static inline void __load_psw(psw_t psw)
245 {
246 	asm volatile("lpswe %0" : : "Q" (psw) : "cc");
247 }
248 
249 /*
250  * Set PSW mask to specified value, while leaving the
251  * PSW addr pointing to the next instruction.
252  */
253 static __no_kasan_or_inline void __load_psw_mask(unsigned long mask)
254 {
255 	unsigned long addr;
256 	psw_t psw;
257 
258 	psw.mask = mask;
259 
260 	asm volatile(
261 		"	larl	%0,1f\n"
262 		"	stg	%0,%1\n"
263 		"	lpswe	%2\n"
264 		"1:"
265 		: "=&d" (addr), "=Q" (psw.addr) : "Q" (psw) : "memory", "cc");
266 }
267 
268 /*
269  * Extract current PSW mask
270  */
271 static inline unsigned long __extract_psw(void)
272 {
273 	unsigned int reg1, reg2;
274 
275 	asm volatile("epsw %0,%1" : "=d" (reg1), "=a" (reg2));
276 	return (((unsigned long) reg1) << 32) | ((unsigned long) reg2);
277 }
278 
279 static inline void local_mcck_enable(void)
280 {
281 	__load_psw_mask(__extract_psw() | PSW_MASK_MCHECK);
282 }
283 
284 static inline void local_mcck_disable(void)
285 {
286 	__load_psw_mask(__extract_psw() & ~PSW_MASK_MCHECK);
287 }
288 
289 /*
290  * Rewind PSW instruction address by specified number of bytes.
291  */
292 static inline unsigned long __rewind_psw(psw_t psw, unsigned long ilc)
293 {
294 	unsigned long mask;
295 
296 	mask = (psw.mask & PSW_MASK_EA) ? -1UL :
297 	       (psw.mask & PSW_MASK_BA) ? (1UL << 31) - 1 :
298 					  (1UL << 24) - 1;
299 	return (psw.addr - ilc) & mask;
300 }
301 
302 /*
303  * Function to stop a processor until the next interrupt occurs
304  */
305 void enabled_wait(void);
306 
307 /*
308  * Function to drop a processor into disabled wait state
309  */
310 static __always_inline void __noreturn disabled_wait(void)
311 {
312 	psw_t psw;
313 
314 	psw.mask = PSW_MASK_BASE | PSW_MASK_WAIT | PSW_MASK_BA | PSW_MASK_EA;
315 	psw.addr = _THIS_IP_;
316 	__load_psw(psw);
317 	while (1);
318 }
319 
320 /*
321  * Basic Machine Check/Program Check Handler.
322  */
323 
324 extern void s390_base_pgm_handler(void);
325 extern void s390_base_ext_handler(void);
326 
327 extern void (*s390_base_pgm_handler_fn)(void);
328 extern void (*s390_base_ext_handler_fn)(void);
329 
330 #define ARCH_LOW_ADDRESS_LIMIT	0x7fffffffUL
331 
332 extern int memcpy_real(void *, void *, size_t);
333 extern void memcpy_absolute(void *, void *, size_t);
334 
335 #define mem_assign_absolute(dest, val) do {			\
336 	__typeof__(dest) __tmp = (val);				\
337 								\
338 	BUILD_BUG_ON(sizeof(__tmp) != sizeof(val));		\
339 	memcpy_absolute(&(dest), &__tmp, sizeof(__tmp));	\
340 } while (0)
341 
342 extern int s390_isolate_bp(void);
343 extern int s390_isolate_bp_guest(void);
344 
345 #endif /* __ASSEMBLY__ */
346 
347 #endif /* __ASM_S390_PROCESSOR_H */
348