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_ENABLED_WAIT 5 /* in enabled wait state */
20 #define CIF_MCCK_GUEST 6 /* machine check happening in guest */
21 #define CIF_DEDICATED_CPU 7 /* this CPU is dedicated */
22
23 #define _CIF_NOHZ_DELAY BIT(CIF_NOHZ_DELAY)
24 #define _CIF_FPU BIT(CIF_FPU)
25 #define _CIF_ENABLED_WAIT BIT(CIF_ENABLED_WAIT)
26 #define _CIF_MCCK_GUEST BIT(CIF_MCCK_GUEST)
27 #define _CIF_DEDICATED_CPU BIT(CIF_DEDICATED_CPU)
28
29 #define RESTART_FLAG_CTLREGS _AC(1 << 0, U)
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 #include <asm/irqflags.h>
44
45 typedef long (*sys_call_ptr_t)(struct pt_regs *regs);
46
set_cpu_flag(int flag)47 static inline void set_cpu_flag(int flag)
48 {
49 S390_lowcore.cpu_flags |= (1UL << flag);
50 }
51
clear_cpu_flag(int flag)52 static inline void clear_cpu_flag(int flag)
53 {
54 S390_lowcore.cpu_flags &= ~(1UL << flag);
55 }
56
test_cpu_flag(int flag)57 static inline int test_cpu_flag(int flag)
58 {
59 return !!(S390_lowcore.cpu_flags & (1UL << flag));
60 }
61
62 /*
63 * Test CIF flag of another CPU. The caller needs to ensure that
64 * CPU hotplug can not happen, e.g. by disabling preemption.
65 */
test_cpu_flag_of(int flag,int cpu)66 static inline int test_cpu_flag_of(int flag, int cpu)
67 {
68 struct lowcore *lc = lowcore_ptr[cpu];
69 return !!(lc->cpu_flags & (1UL << flag));
70 }
71
72 #define arch_needs_cpu() test_cpu_flag(CIF_NOHZ_DELAY)
73
get_cpu_id(struct cpuid * ptr)74 static inline void get_cpu_id(struct cpuid *ptr)
75 {
76 asm volatile("stidp %0" : "=Q" (*ptr));
77 }
78
79 void s390_adjust_jiffies(void);
80 void s390_update_cpu_mhz(void);
81 void cpu_detect_mhz_feature(void);
82
83 extern const struct seq_operations cpuinfo_op;
84 extern void execve_tail(void);
85 extern void __bpon(void);
86 unsigned long vdso_size(void);
87
88 /*
89 * User space process size: 2GB for 31 bit, 4TB or 8PT for 64 bit.
90 */
91
92 #define TASK_SIZE (test_thread_flag(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_MAX (-PAGE_SIZE)
97
98 #define VDSO_BASE (STACK_TOP + PAGE_SIZE)
99 #define VDSO_LIMIT (test_thread_flag(TIF_31BIT) ? _REGION3_SIZE : _REGION2_SIZE)
100 #define STACK_TOP (VDSO_LIMIT - vdso_size() - PAGE_SIZE)
101 #define STACK_TOP_MAX (_REGION2_SIZE - vdso_size() - PAGE_SIZE)
102
103 #define HAVE_ARCH_PICK_MMAP_LAYOUT
104
105 /*
106 * Thread structure
107 */
108 struct thread_struct {
109 unsigned int acrs[NUM_ACRS];
110 unsigned long ksp; /* kernel stack pointer */
111 unsigned long user_timer; /* task cputime in user space */
112 unsigned long guest_timer; /* task cputime in kvm guest */
113 unsigned long system_timer; /* task cputime in kernel space */
114 unsigned long hardirq_timer; /* task cputime in hardirq context */
115 unsigned long softirq_timer; /* task cputime in softirq context */
116 const sys_call_ptr_t *sys_call_table; /* system call table address */
117 unsigned long gmap_addr; /* address of last gmap fault. */
118 unsigned int gmap_write_flag; /* gmap fault write indication */
119 unsigned int gmap_int_code; /* int code of last gmap fault */
120 unsigned int gmap_pfault; /* signal of a pending guest pfault */
121
122 /* Per-thread information related to debugging */
123 struct per_regs per_user; /* User specified PER registers */
124 struct per_event per_event; /* Cause of the last PER trap */
125 unsigned long per_flags; /* Flags to control debug behavior */
126 unsigned int system_call; /* system call number in signal */
127 unsigned long last_break; /* last breaking-event-address. */
128 /* pfault_wait is used to block the process on a pfault event */
129 unsigned long pfault_wait;
130 struct list_head list;
131 /* cpu runtime instrumentation */
132 struct runtime_instr_cb *ri_cb;
133 struct gs_cb *gs_cb; /* Current guarded storage cb */
134 struct gs_cb *gs_bc_cb; /* Broadcast guarded storage cb */
135 struct pgm_tdb trap_tdb; /* Transaction abort diagnose block */
136 /*
137 * Warning: 'fpu' is dynamically-sized. It *MUST* be at
138 * the end.
139 */
140 struct fpu fpu; /* FP and VX register save area */
141 };
142
143 /* Flag to disable transactions. */
144 #define PER_FLAG_NO_TE 1UL
145 /* Flag to enable random transaction aborts. */
146 #define PER_FLAG_TE_ABORT_RAND 2UL
147 /* Flag to specify random transaction abort mode:
148 * - abort each transaction at a random instruction before TEND if set.
149 * - abort random transactions at a random instruction if cleared.
150 */
151 #define PER_FLAG_TE_ABORT_RAND_TEND 4UL
152
153 typedef struct thread_struct thread_struct;
154
155 #define ARCH_MIN_TASKALIGN 8
156
157 #define INIT_THREAD { \
158 .ksp = sizeof(init_stack) + (unsigned long) &init_stack, \
159 .fpu.regs = (void *) init_task.thread.fpu.fprs, \
160 .last_break = 1, \
161 }
162
163 /*
164 * Do necessary setup to start up a new thread.
165 */
166 #define start_thread(regs, new_psw, new_stackp) do { \
167 regs->psw.mask = PSW_USER_BITS | PSW_MASK_EA | PSW_MASK_BA; \
168 regs->psw.addr = new_psw; \
169 regs->gprs[15] = new_stackp; \
170 execve_tail(); \
171 } while (0)
172
173 #define start_thread31(regs, new_psw, new_stackp) do { \
174 regs->psw.mask = PSW_USER_BITS | PSW_MASK_BA; \
175 regs->psw.addr = new_psw; \
176 regs->gprs[15] = new_stackp; \
177 execve_tail(); \
178 } while (0)
179
180 /* Forward declaration, a strange C thing */
181 struct task_struct;
182 struct mm_struct;
183 struct seq_file;
184 struct pt_regs;
185
186 void show_registers(struct pt_regs *regs);
187 void show_cacheinfo(struct seq_file *m);
188
189 /* Free guarded storage control block */
190 void guarded_storage_release(struct task_struct *tsk);
191 void gs_load_bc_cb(struct pt_regs *regs);
192
193 unsigned long __get_wchan(struct task_struct *p);
194 #define task_pt_regs(tsk) ((struct pt_regs *) \
195 (task_stack_page(tsk) + THREAD_SIZE) - 1)
196 #define KSTK_EIP(tsk) (task_pt_regs(tsk)->psw.addr)
197 #define KSTK_ESP(tsk) (task_pt_regs(tsk)->gprs[15])
198
199 /* Has task runtime instrumentation enabled ? */
200 #define is_ri_task(tsk) (!!(tsk)->thread.ri_cb)
201
202 /* avoid using global register due to gcc bug in versions < 8.4 */
203 #define current_stack_pointer (__current_stack_pointer())
204
__current_stack_pointer(void)205 static __always_inline unsigned long __current_stack_pointer(void)
206 {
207 unsigned long sp;
208
209 asm volatile("lgr %0,15" : "=d" (sp));
210 return sp;
211 }
212
stap(void)213 static __always_inline unsigned short stap(void)
214 {
215 unsigned short cpu_address;
216
217 asm volatile("stap %0" : "=Q" (cpu_address));
218 return cpu_address;
219 }
220
221 #define cpu_relax() barrier()
222
223 #define ECAG_CACHE_ATTRIBUTE 0
224 #define ECAG_CPU_ATTRIBUTE 1
225
__ecag(unsigned int asi,unsigned char parm)226 static inline unsigned long __ecag(unsigned int asi, unsigned char parm)
227 {
228 unsigned long val;
229
230 asm volatile("ecag %0,0,0(%1)" : "=d" (val) : "a" (asi << 8 | parm));
231 return val;
232 }
233
psw_set_key(unsigned int key)234 static inline void psw_set_key(unsigned int key)
235 {
236 asm volatile("spka 0(%0)" : : "d" (key));
237 }
238
239 /*
240 * Set PSW to specified value.
241 */
__load_psw(psw_t psw)242 static inline void __load_psw(psw_t psw)
243 {
244 asm volatile("lpswe %0" : : "Q" (psw) : "cc");
245 }
246
247 /*
248 * Set PSW mask to specified value, while leaving the
249 * PSW addr pointing to the next instruction.
250 */
__load_psw_mask(unsigned long mask)251 static __always_inline void __load_psw_mask(unsigned long mask)
252 {
253 unsigned long addr;
254 psw_t psw;
255
256 psw.mask = mask;
257
258 asm volatile(
259 " larl %0,1f\n"
260 " stg %0,%1\n"
261 " lpswe %2\n"
262 "1:"
263 : "=&d" (addr), "=Q" (psw.addr) : "Q" (psw) : "memory", "cc");
264 }
265
266 /*
267 * Extract current PSW mask
268 */
__extract_psw(void)269 static inline unsigned long __extract_psw(void)
270 {
271 unsigned int reg1, reg2;
272
273 asm volatile("epsw %0,%1" : "=d" (reg1), "=a" (reg2));
274 return (((unsigned long) reg1) << 32) | ((unsigned long) reg2);
275 }
276
local_mcck_enable(void)277 static inline void local_mcck_enable(void)
278 {
279 __load_psw_mask(__extract_psw() | PSW_MASK_MCHECK);
280 }
281
local_mcck_disable(void)282 static inline void local_mcck_disable(void)
283 {
284 __load_psw_mask(__extract_psw() & ~PSW_MASK_MCHECK);
285 }
286
287 /*
288 * Rewind PSW instruction address by specified number of bytes.
289 */
__rewind_psw(psw_t psw,unsigned long ilc)290 static inline unsigned long __rewind_psw(psw_t psw, unsigned long ilc)
291 {
292 unsigned long mask;
293
294 mask = (psw.mask & PSW_MASK_EA) ? -1UL :
295 (psw.mask & PSW_MASK_BA) ? (1UL << 31) - 1 :
296 (1UL << 24) - 1;
297 return (psw.addr - ilc) & mask;
298 }
299
300 /*
301 * Function to drop a processor into disabled wait state
302 */
disabled_wait(void)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 #define ARCH_LOW_ADDRESS_LIMIT 0x7fffffffUL
314
315 extern int s390_isolate_bp(void);
316 extern int s390_isolate_bp_guest(void);
317
regs_irqs_disabled(struct pt_regs * regs)318 static __always_inline bool regs_irqs_disabled(struct pt_regs *regs)
319 {
320 return arch_irqs_disabled_flags(regs->psw.mask);
321 }
322
323 #endif /* __ASSEMBLY__ */
324
325 #endif /* __ASM_S390_PROCESSOR_H */
326