xref: /linux/arch/s390/include/asm/processor.h (revision c717993dd76a1049093af5c262e751d901b8da10)
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  
47  static inline void set_cpu_flag(int flag)
48  {
49  	S390_lowcore.cpu_flags |= (1UL << flag);
50  }
51  
52  static inline void clear_cpu_flag(int flag)
53  {
54  	S390_lowcore.cpu_flags &= ~(1UL << flag);
55  }
56  
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   */
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  
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  
87  /*
88   * User space process size: 2GB for 31 bit, 4TB or 8PT for 64 bit.
89   */
90  
91  #define TASK_SIZE		(test_thread_flag(TIF_31BIT) ? \
92  					_REGION3_SIZE : TASK_SIZE_MAX)
93  #define TASK_UNMAPPED_BASE	(test_thread_flag(TIF_31BIT) ? \
94  					(_REGION3_SIZE >> 1) : (_REGION2_SIZE >> 1))
95  #define TASK_SIZE_MAX		(-PAGE_SIZE)
96  
97  #define STACK_TOP		(test_thread_flag(TIF_31BIT) ? \
98  					_REGION3_SIZE : _REGION2_SIZE)
99  #define STACK_TOP_MAX		_REGION2_SIZE
100  
101  #define HAVE_ARCH_PICK_MMAP_LAYOUT
102  
103  /*
104   * Thread structure
105   */
106  struct thread_struct {
107  	unsigned int  acrs[NUM_ACRS];
108  	unsigned long ksp;			/* kernel stack pointer */
109  	unsigned long user_timer;		/* task cputime in user space */
110  	unsigned long guest_timer;		/* task cputime in kvm guest */
111  	unsigned long system_timer;		/* task cputime in kernel space */
112  	unsigned long hardirq_timer;		/* task cputime in hardirq context */
113  	unsigned long softirq_timer;		/* task cputime in softirq context */
114  	const sys_call_ptr_t *sys_call_table;	/* system call table address */
115  	unsigned long gmap_addr;		/* address of last gmap fault. */
116  	unsigned int gmap_write_flag;		/* gmap fault write indication */
117  	unsigned int gmap_int_code;		/* int code of last gmap fault */
118  	unsigned int gmap_pfault;		/* signal of a pending guest pfault */
119  
120  	/* Per-thread information related to debugging */
121  	struct per_regs per_user;		/* User specified PER registers */
122  	struct per_event per_event;		/* Cause of the last PER trap */
123  	unsigned long per_flags;		/* Flags to control debug behavior */
124  	unsigned int system_call;		/* system call number in signal */
125  	unsigned long last_break;		/* last breaking-event-address. */
126  	/* pfault_wait is used to block the process on a pfault event */
127  	unsigned long pfault_wait;
128  	struct list_head list;
129  	/* cpu runtime instrumentation */
130  	struct runtime_instr_cb *ri_cb;
131  	struct gs_cb *gs_cb;			/* Current guarded storage cb */
132  	struct gs_cb *gs_bc_cb;			/* Broadcast guarded storage cb */
133  	struct pgm_tdb trap_tdb;		/* Transaction abort diagnose block */
134  	/*
135  	 * Warning: 'fpu' is dynamically-sized. It *MUST* be at
136  	 * the end.
137  	 */
138  	struct fpu fpu;			/* FP and VX register save area */
139  };
140  
141  /* Flag to disable transactions. */
142  #define PER_FLAG_NO_TE			1UL
143  /* Flag to enable random transaction aborts. */
144  #define PER_FLAG_TE_ABORT_RAND		2UL
145  /* Flag to specify random transaction abort mode:
146   * - abort each transaction at a random instruction before TEND if set.
147   * - abort random transactions at a random instruction if cleared.
148   */
149  #define PER_FLAG_TE_ABORT_RAND_TEND	4UL
150  
151  typedef struct thread_struct thread_struct;
152  
153  #define ARCH_MIN_TASKALIGN	8
154  
155  #define INIT_THREAD {							\
156  	.ksp = sizeof(init_stack) + (unsigned long) &init_stack,	\
157  	.fpu.regs = (void *) init_task.thread.fpu.fprs,			\
158  	.last_break = 1,						\
159  }
160  
161  /*
162   * Do necessary setup to start up a new thread.
163   */
164  #define start_thread(regs, new_psw, new_stackp) do {			\
165  	regs->psw.mask	= PSW_USER_BITS | PSW_MASK_EA | PSW_MASK_BA;	\
166  	regs->psw.addr	= new_psw;					\
167  	regs->gprs[15]	= new_stackp;					\
168  	execve_tail();							\
169  } while (0)
170  
171  #define start_thread31(regs, new_psw, new_stackp) do {			\
172  	regs->psw.mask	= PSW_USER_BITS | PSW_MASK_BA;			\
173  	regs->psw.addr	= new_psw;					\
174  	regs->gprs[15]	= new_stackp;					\
175  	execve_tail();							\
176  } while (0)
177  
178  /* Forward declaration, a strange C thing */
179  struct task_struct;
180  struct mm_struct;
181  struct seq_file;
182  struct pt_regs;
183  
184  void show_registers(struct pt_regs *regs);
185  void show_cacheinfo(struct seq_file *m);
186  
187  /* Free all resources held by a thread. */
188  static inline void release_thread(struct task_struct *tsk) { }
189  
190  /* Free guarded storage control block */
191  void guarded_storage_release(struct task_struct *tsk);
192  void gs_load_bc_cb(struct pt_regs *regs);
193  
194  unsigned long __get_wchan(struct task_struct *p);
195  #define task_pt_regs(tsk) ((struct pt_regs *) \
196          (task_stack_page(tsk) + THREAD_SIZE) - 1)
197  #define KSTK_EIP(tsk)	(task_pt_regs(tsk)->psw.addr)
198  #define KSTK_ESP(tsk)	(task_pt_regs(tsk)->gprs[15])
199  
200  /* Has task runtime instrumentation enabled ? */
201  #define is_ri_task(tsk) (!!(tsk)->thread.ri_cb)
202  
203  static __always_inline unsigned long current_stack_pointer(void)
204  {
205  	unsigned long sp;
206  
207  	asm volatile("la %0,0(15)" : "=a" (sp));
208  	return sp;
209  }
210  
211  static __always_inline unsigned short stap(void)
212  {
213  	unsigned short cpu_address;
214  
215  	asm volatile("stap %0" : "=Q" (cpu_address));
216  	return cpu_address;
217  }
218  
219  #define cpu_relax() barrier()
220  
221  #define ECAG_CACHE_ATTRIBUTE	0
222  #define ECAG_CPU_ATTRIBUTE	1
223  
224  static inline unsigned long __ecag(unsigned int asi, unsigned char parm)
225  {
226  	unsigned long val;
227  
228  	asm volatile(".insn	rsy,0xeb000000004c,%0,0,0(%1)" /* ecag */
229  		     : "=d" (val) : "a" (asi << 8 | parm));
230  	return val;
231  }
232  
233  static inline void psw_set_key(unsigned int key)
234  {
235  	asm volatile("spka 0(%0)" : : "d" (key));
236  }
237  
238  /*
239   * Set PSW to specified value.
240   */
241  static inline void __load_psw(psw_t psw)
242  {
243  	asm volatile("lpswe %0" : : "Q" (psw) : "cc");
244  }
245  
246  /*
247   * Set PSW mask to specified value, while leaving the
248   * PSW addr pointing to the next instruction.
249   */
250  static __always_inline void __load_psw_mask(unsigned long mask)
251  {
252  	unsigned long addr;
253  	psw_t psw;
254  
255  	psw.mask = mask;
256  
257  	asm volatile(
258  		"	larl	%0,1f\n"
259  		"	stg	%0,%1\n"
260  		"	lpswe	%2\n"
261  		"1:"
262  		: "=&d" (addr), "=Q" (psw.addr) : "Q" (psw) : "memory", "cc");
263  }
264  
265  /*
266   * Extract current PSW mask
267   */
268  static inline unsigned long __extract_psw(void)
269  {
270  	unsigned int reg1, reg2;
271  
272  	asm volatile("epsw %0,%1" : "=d" (reg1), "=a" (reg2));
273  	return (((unsigned long) reg1) << 32) | ((unsigned long) reg2);
274  }
275  
276  static inline void local_mcck_enable(void)
277  {
278  	__load_psw_mask(__extract_psw() | PSW_MASK_MCHECK);
279  }
280  
281  static inline void local_mcck_disable(void)
282  {
283  	__load_psw_mask(__extract_psw() & ~PSW_MASK_MCHECK);
284  }
285  
286  /*
287   * Rewind PSW instruction address by specified number of bytes.
288   */
289  static inline unsigned long __rewind_psw(psw_t psw, unsigned long ilc)
290  {
291  	unsigned long mask;
292  
293  	mask = (psw.mask & PSW_MASK_EA) ? -1UL :
294  	       (psw.mask & PSW_MASK_BA) ? (1UL << 31) - 1 :
295  					  (1UL << 24) - 1;
296  	return (psw.addr - ilc) & mask;
297  }
298  
299  /*
300   * Function to drop a processor into disabled wait state
301   */
302  static __always_inline void __noreturn disabled_wait(void)
303  {
304  	psw_t psw;
305  
306  	psw.mask = PSW_MASK_BASE | PSW_MASK_WAIT | PSW_MASK_BA | PSW_MASK_EA;
307  	psw.addr = _THIS_IP_;
308  	__load_psw(psw);
309  	while (1);
310  }
311  
312  /*
313   * Basic Program Check Handler.
314   */
315  extern void s390_base_pgm_handler(void);
316  extern void (*s390_base_pgm_handler_fn)(void);
317  
318  #define ARCH_LOW_ADDRESS_LIMIT	0x7fffffffUL
319  
320  extern int memcpy_real(void *, void *, size_t);
321  extern void memcpy_absolute(void *, void *, size_t);
322  
323  #define mem_assign_absolute(dest, val) do {			\
324  	__typeof__(dest) __tmp = (val);				\
325  								\
326  	BUILD_BUG_ON(sizeof(__tmp) != sizeof(val));		\
327  	memcpy_absolute(&(dest), &__tmp, sizeof(__tmp));	\
328  } while (0)
329  
330  extern int s390_isolate_bp(void);
331  extern int s390_isolate_bp_guest(void);
332  
333  static __always_inline bool regs_irqs_disabled(struct pt_regs *regs)
334  {
335  	return arch_irqs_disabled_flags(regs->psw.mask);
336  }
337  
338  #endif /* __ASSEMBLY__ */
339  
340  #endif /* __ASM_S390_PROCESSOR_H */
341