xref: /openbmc/linux/arch/s390/include/asm/processor.h (revision 33fb626b)
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_NOHZ_DELAY		2	/* delay HZ disable for a tick */
18 #define CIF_FPU			3	/* restore FPU registers */
19 #define CIF_IGNORE_IRQ		4	/* ignore interrupt (for udelay) */
20 #define CIF_ENABLED_WAIT	5	/* in enabled wait state */
21 #define CIF_MCCK_GUEST		6	/* machine check happening in guest */
22 #define CIF_DEDICATED_CPU	7	/* this CPU is dedicated */
23 
24 #define _CIF_NOHZ_DELAY		BIT(CIF_NOHZ_DELAY)
25 #define _CIF_FPU		BIT(CIF_FPU)
26 #define _CIF_IGNORE_IRQ		BIT(CIF_IGNORE_IRQ)
27 #define _CIF_ENABLED_WAIT	BIT(CIF_ENABLED_WAIT)
28 #define _CIF_MCCK_GUEST		BIT(CIF_MCCK_GUEST)
29 #define _CIF_DEDICATED_CPU	BIT(CIF_DEDICATED_CPU)
30 
31 #ifndef __ASSEMBLY__
32 
33 #include <linux/cpumask.h>
34 #include <linux/linkage.h>
35 #include <linux/irqflags.h>
36 #include <asm/cpu.h>
37 #include <asm/page.h>
38 #include <asm/ptrace.h>
39 #include <asm/setup.h>
40 #include <asm/runtime_instr.h>
41 #include <asm/fpu/types.h>
42 #include <asm/fpu/internal.h>
43 
44 static inline void set_cpu_flag(int flag)
45 {
46 	S390_lowcore.cpu_flags |= (1UL << flag);
47 }
48 
49 static inline void clear_cpu_flag(int flag)
50 {
51 	S390_lowcore.cpu_flags &= ~(1UL << flag);
52 }
53 
54 static inline int test_cpu_flag(int flag)
55 {
56 	return !!(S390_lowcore.cpu_flags & (1UL << flag));
57 }
58 
59 /*
60  * Test CIF flag of another CPU. The caller needs to ensure that
61  * CPU hotplug can not happen, e.g. by disabling preemption.
62  */
63 static inline int test_cpu_flag_of(int flag, int cpu)
64 {
65 	struct lowcore *lc = lowcore_ptr[cpu];
66 	return !!(lc->cpu_flags & (1UL << flag));
67 }
68 
69 #define arch_needs_cpu() test_cpu_flag(CIF_NOHZ_DELAY)
70 
71 static inline void get_cpu_id(struct cpuid *ptr)
72 {
73 	asm volatile("stidp %0" : "=Q" (*ptr));
74 }
75 
76 void s390_adjust_jiffies(void);
77 void s390_update_cpu_mhz(void);
78 void cpu_detect_mhz_feature(void);
79 
80 extern const struct seq_operations cpuinfo_op;
81 extern void execve_tail(void);
82 extern void __bpon(void);
83 
84 /*
85  * User space process size: 2GB for 31 bit, 4TB or 8PT for 64 bit.
86  */
87 
88 #define TASK_SIZE_OF(tsk)	(test_tsk_thread_flag(tsk, TIF_31BIT) ? \
89 					_REGION3_SIZE : TASK_SIZE_MAX)
90 #define TASK_UNMAPPED_BASE	(test_thread_flag(TIF_31BIT) ? \
91 					(_REGION3_SIZE >> 1) : (_REGION2_SIZE >> 1))
92 #define TASK_SIZE		TASK_SIZE_OF(current)
93 #define TASK_SIZE_MAX		(-PAGE_SIZE)
94 
95 #define STACK_TOP		(test_thread_flag(TIF_31BIT) ? \
96 					_REGION3_SIZE : _REGION2_SIZE)
97 #define STACK_TOP_MAX		_REGION2_SIZE
98 
99 #define HAVE_ARCH_PICK_MMAP_LAYOUT
100 
101 /*
102  * Thread structure
103  */
104 struct thread_struct {
105 	unsigned int  acrs[NUM_ACRS];
106         unsigned long ksp;              /* kernel stack pointer             */
107 	unsigned long user_timer;	/* task cputime in user space */
108 	unsigned long guest_timer;	/* task cputime in kvm guest */
109 	unsigned long system_timer;	/* task cputime in kernel space */
110 	unsigned long hardirq_timer;	/* task cputime in hardirq context */
111 	unsigned long softirq_timer;	/* task cputime in softirq context */
112 	unsigned long sys_call_table;	/* system call table address */
113 	unsigned long gmap_addr;	/* address of last gmap fault. */
114 	unsigned int gmap_write_flag;	/* gmap fault write indication */
115 	unsigned int gmap_int_code;	/* int code of last gmap fault */
116 	unsigned int gmap_pfault;	/* signal of a pending guest pfault */
117 	/* Per-thread information related to debugging */
118 	struct per_regs per_user;	/* User specified PER registers */
119 	struct per_event per_event;	/* Cause of the last PER trap */
120 	unsigned long per_flags;	/* Flags to control debug behavior */
121 	unsigned int system_call;	/* system call number in signal */
122 	unsigned long last_break;	/* last breaking-event-address. */
123         /* pfault_wait is used to block the process on a pfault event */
124 	unsigned long pfault_wait;
125 	struct list_head list;
126 	/* cpu runtime instrumentation */
127 	struct runtime_instr_cb *ri_cb;
128 	struct gs_cb *gs_cb;		/* Current guarded storage cb */
129 	struct gs_cb *gs_bc_cb;		/* Broadcast guarded storage cb */
130 	unsigned char trap_tdb[256];	/* Transaction abort diagnose block */
131 	/*
132 	 * Warning: 'fpu' is dynamically-sized. It *MUST* be at
133 	 * the end.
134 	 */
135 	struct fpu fpu;			/* FP and VX register save area */
136 };
137 
138 /* Flag to disable transactions. */
139 #define PER_FLAG_NO_TE			1UL
140 /* Flag to enable random transaction aborts. */
141 #define PER_FLAG_TE_ABORT_RAND		2UL
142 /* Flag to specify random transaction abort mode:
143  * - abort each transaction at a random instruction before TEND if set.
144  * - abort random transactions at a random instruction if cleared.
145  */
146 #define PER_FLAG_TE_ABORT_RAND_TEND	4UL
147 
148 typedef struct thread_struct thread_struct;
149 
150 #define ARCH_MIN_TASKALIGN	8
151 
152 #define INIT_THREAD {							\
153 	.ksp = sizeof(init_stack) + (unsigned long) &init_stack,	\
154 	.fpu.regs = (void *) init_task.thread.fpu.fprs,			\
155 	.last_break = 1,						\
156 }
157 
158 /*
159  * Do necessary setup to start up a new thread.
160  */
161 #define start_thread(regs, new_psw, new_stackp) do {			\
162 	regs->psw.mask	= PSW_USER_BITS | PSW_MASK_EA | PSW_MASK_BA;	\
163 	regs->psw.addr	= new_psw;					\
164 	regs->gprs[15]	= new_stackp;					\
165 	execve_tail();							\
166 } while (0)
167 
168 #define start_thread31(regs, new_psw, new_stackp) do {			\
169 	regs->psw.mask	= PSW_USER_BITS | PSW_MASK_BA;			\
170 	regs->psw.addr	= new_psw;					\
171 	regs->gprs[15]	= new_stackp;					\
172 	execve_tail();							\
173 } while (0)
174 
175 /* Forward declaration, a strange C thing */
176 struct task_struct;
177 struct mm_struct;
178 struct seq_file;
179 struct pt_regs;
180 
181 void show_registers(struct pt_regs *regs);
182 void show_cacheinfo(struct seq_file *m);
183 
184 /* Free all resources held by a thread. */
185 static inline void release_thread(struct task_struct *tsk) { }
186 
187 /* Free guarded storage control block */
188 void guarded_storage_release(struct task_struct *tsk);
189 
190 unsigned long get_wchan(struct task_struct *p);
191 #define task_pt_regs(tsk) ((struct pt_regs *) \
192         (task_stack_page(tsk) + THREAD_SIZE) - 1)
193 #define KSTK_EIP(tsk)	(task_pt_regs(tsk)->psw.addr)
194 #define KSTK_ESP(tsk)	(task_pt_regs(tsk)->gprs[15])
195 
196 /* Has task runtime instrumentation enabled ? */
197 #define is_ri_task(tsk) (!!(tsk)->thread.ri_cb)
198 
199 static __always_inline unsigned long current_stack_pointer(void)
200 {
201 	unsigned long sp;
202 
203 	asm volatile("la %0,0(15)" : "=a" (sp));
204 	return sp;
205 }
206 
207 static __no_kasan_or_inline unsigned short stap(void)
208 {
209 	unsigned short cpu_address;
210 
211 	asm volatile("stap %0" : "=Q" (cpu_address));
212 	return cpu_address;
213 }
214 
215 #define cpu_relax() barrier()
216 
217 #define ECAG_CACHE_ATTRIBUTE	0
218 #define ECAG_CPU_ATTRIBUTE	1
219 
220 static inline unsigned long __ecag(unsigned int asi, unsigned char parm)
221 {
222 	unsigned long val;
223 
224 	asm volatile(".insn	rsy,0xeb000000004c,%0,0,0(%1)" /* ecag */
225 		     : "=d" (val) : "a" (asi << 8 | parm));
226 	return val;
227 }
228 
229 static inline void psw_set_key(unsigned int key)
230 {
231 	asm volatile("spka 0(%0)" : : "d" (key));
232 }
233 
234 /*
235  * Set PSW to specified value.
236  */
237 static inline void __load_psw(psw_t psw)
238 {
239 	asm volatile("lpswe %0" : : "Q" (psw) : "cc");
240 }
241 
242 /*
243  * Set PSW mask to specified value, while leaving the
244  * PSW addr pointing to the next instruction.
245  */
246 static __no_kasan_or_inline void __load_psw_mask(unsigned long mask)
247 {
248 	unsigned long addr;
249 	psw_t psw;
250 
251 	psw.mask = mask;
252 
253 	asm volatile(
254 		"	larl	%0,1f\n"
255 		"	stg	%0,%1\n"
256 		"	lpswe	%2\n"
257 		"1:"
258 		: "=&d" (addr), "=Q" (psw.addr) : "Q" (psw) : "memory", "cc");
259 }
260 
261 /*
262  * Extract current PSW mask
263  */
264 static inline unsigned long __extract_psw(void)
265 {
266 	unsigned int reg1, reg2;
267 
268 	asm volatile("epsw %0,%1" : "=d" (reg1), "=a" (reg2));
269 	return (((unsigned long) reg1) << 32) | ((unsigned long) reg2);
270 }
271 
272 static inline void local_mcck_enable(void)
273 {
274 	__load_psw_mask(__extract_psw() | PSW_MASK_MCHECK);
275 }
276 
277 static inline void local_mcck_disable(void)
278 {
279 	__load_psw_mask(__extract_psw() & ~PSW_MASK_MCHECK);
280 }
281 
282 /*
283  * Rewind PSW instruction address by specified number of bytes.
284  */
285 static inline unsigned long __rewind_psw(psw_t psw, unsigned long ilc)
286 {
287 	unsigned long mask;
288 
289 	mask = (psw.mask & PSW_MASK_EA) ? -1UL :
290 	       (psw.mask & PSW_MASK_BA) ? (1UL << 31) - 1 :
291 					  (1UL << 24) - 1;
292 	return (psw.addr - ilc) & mask;
293 }
294 
295 /*
296  * Function to stop a processor until the next interrupt occurs
297  */
298 void enabled_wait(void);
299 
300 /*
301  * Function to drop a processor into disabled wait state
302  */
303 static __always_inline void __noreturn disabled_wait(void)
304 {
305 	psw_t psw;
306 
307 	psw.mask = PSW_MASK_BASE | PSW_MASK_WAIT | PSW_MASK_BA | PSW_MASK_EA;
308 	psw.addr = _THIS_IP_;
309 	__load_psw(psw);
310 	while (1);
311 }
312 
313 /*
314  * Basic Program Check Handler.
315  */
316 extern void s390_base_pgm_handler(void);
317 extern void (*s390_base_pgm_handler_fn)(void);
318 
319 #define ARCH_LOW_ADDRESS_LIMIT	0x7fffffffUL
320 
321 extern int memcpy_real(void *, void *, size_t);
322 extern void memcpy_absolute(void *, void *, size_t);
323 
324 #define mem_assign_absolute(dest, val) do {			\
325 	__typeof__(dest) __tmp = (val);				\
326 								\
327 	BUILD_BUG_ON(sizeof(__tmp) != sizeof(val));		\
328 	memcpy_absolute(&(dest), &__tmp, sizeof(__tmp));	\
329 } while (0)
330 
331 extern int s390_isolate_bp(void);
332 extern int s390_isolate_bp_guest(void);
333 
334 #endif /* __ASSEMBLY__ */
335 
336 #endif /* __ASM_S390_PROCESSOR_H */
337