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  
set_cpu_flag(int flag)50  static inline void set_cpu_flag(int flag)
51  {
52  	S390_lowcore.cpu_flags |= (1UL << flag);
53  }
54  
clear_cpu_flag(int flag)55  static inline void clear_cpu_flag(int flag)
56  {
57  	S390_lowcore.cpu_flags &= ~(1UL << flag);
58  }
59  
test_cpu_flag(int flag)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   */
test_cpu_flag_of(int flag,int cpu)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  
get_cpu_id(struct cpuid * ptr)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 int sysctl_ieee_emulation_warnings;
88  extern void execve_tail(void);
89  extern void __bpon(void);
90  
91  /*
92   * User space process size: 2GB for 31 bit, 4TB or 8PT for 64 bit.
93   */
94  
95  #define TASK_SIZE_OF(tsk)	(test_tsk_thread_flag(tsk, TIF_31BIT) ? \
96  					(1UL << 31) : -PAGE_SIZE)
97  #define TASK_UNMAPPED_BASE	(test_thread_flag(TIF_31BIT) ? \
98  					(1UL << 30) : (1UL << 41))
99  #define TASK_SIZE		TASK_SIZE_OF(current)
100  #define TASK_SIZE_MAX		(-PAGE_SIZE)
101  
102  #define STACK_TOP		(test_thread_flag(TIF_31BIT) ? \
103  					(1UL << 31) : (1UL << 42))
104  #define STACK_TOP_MAX		(1UL << 42)
105  
106  #define HAVE_ARCH_PICK_MMAP_LAYOUT
107  
108  typedef unsigned int mm_segment_t;
109  
110  /*
111   * Thread structure
112   */
113  struct thread_struct {
114  	unsigned int  acrs[NUM_ACRS];
115          unsigned long ksp;              /* kernel stack pointer             */
116  	unsigned long user_timer;	/* task cputime in user space */
117  	unsigned long guest_timer;	/* task cputime in kvm guest */
118  	unsigned long system_timer;	/* task cputime in kernel space */
119  	unsigned long hardirq_timer;	/* task cputime in hardirq context */
120  	unsigned long softirq_timer;	/* task cputime in softirq context */
121  	unsigned long sys_call_table;	/* system call table address */
122  	mm_segment_t mm_segment;
123  	unsigned long gmap_addr;	/* address of last gmap fault. */
124  	unsigned int gmap_write_flag;	/* gmap fault write indication */
125  	unsigned int gmap_int_code;	/* int code of last gmap fault */
126  	unsigned int gmap_pfault;	/* signal of a pending guest pfault */
127  	/* Per-thread information related to debugging */
128  	struct per_regs per_user;	/* User specified PER registers */
129  	struct per_event per_event;	/* Cause of the last PER trap */
130  	unsigned long per_flags;	/* Flags to control debug behavior */
131  	unsigned int system_call;	/* system call number in signal */
132  	unsigned long last_break;	/* last breaking-event-address. */
133          /* pfault_wait is used to block the process on a pfault event */
134  	unsigned long pfault_wait;
135  	struct list_head list;
136  	/* cpu runtime instrumentation */
137  	struct runtime_instr_cb *ri_cb;
138  	struct gs_cb *gs_cb;		/* Current guarded storage cb */
139  	struct gs_cb *gs_bc_cb;		/* Broadcast guarded storage cb */
140  	unsigned char trap_tdb[256];	/* Transaction abort diagnose block */
141  	/*
142  	 * Warning: 'fpu' is dynamically-sized. It *MUST* be at
143  	 * the end.
144  	 */
145  	struct fpu fpu;			/* FP and VX register save area */
146  };
147  
148  /* Flag to disable transactions. */
149  #define PER_FLAG_NO_TE			1UL
150  /* Flag to enable random transaction aborts. */
151  #define PER_FLAG_TE_ABORT_RAND		2UL
152  /* Flag to specify random transaction abort mode:
153   * - abort each transaction at a random instruction before TEND if set.
154   * - abort random transactions at a random instruction if cleared.
155   */
156  #define PER_FLAG_TE_ABORT_RAND_TEND	4UL
157  
158  typedef struct thread_struct thread_struct;
159  
160  #define ARCH_MIN_TASKALIGN	8
161  
162  #define INIT_THREAD {							\
163  	.ksp = sizeof(init_stack) + (unsigned long) &init_stack,	\
164  	.fpu.regs = (void *) init_task.thread.fpu.fprs,			\
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  	crst_table_downgrade(current->mm);				\
182  	execve_tail();							\
183  } while (0)
184  
185  /* Forward declaration, a strange C thing */
186  struct task_struct;
187  struct mm_struct;
188  struct seq_file;
189  struct pt_regs;
190  
191  void show_registers(struct pt_regs *regs);
192  void show_cacheinfo(struct seq_file *m);
193  
194  /* Free all resources held by a thread. */
release_thread(struct task_struct * tsk)195  static inline void release_thread(struct task_struct *tsk) { }
196  
197  /* Free guarded storage control block */
198  void guarded_storage_release(struct task_struct *tsk);
199  
200  unsigned long get_wchan(struct task_struct *p);
201  #define task_pt_regs(tsk) ((struct pt_regs *) \
202          (task_stack_page(tsk) + THREAD_SIZE) - 1)
203  #define KSTK_EIP(tsk)	(task_pt_regs(tsk)->psw.addr)
204  #define KSTK_ESP(tsk)	(task_pt_regs(tsk)->gprs[15])
205  
206  /* Has task runtime instrumentation enabled ? */
207  #define is_ri_task(tsk) (!!(tsk)->thread.ri_cb)
208  
current_stack_pointer(void)209  static inline unsigned long current_stack_pointer(void)
210  {
211  	unsigned long sp;
212  
213  	asm volatile("la %0,0(15)" : "=a" (sp));
214  	return sp;
215  }
216  
stap(void)217  static __no_kasan_or_inline unsigned short stap(void)
218  {
219  	unsigned short cpu_address;
220  
221  	asm volatile("stap %0" : "=Q" (cpu_address));
222  	return cpu_address;
223  }
224  
225  #define cpu_relax() barrier()
226  
227  #define ECAG_CACHE_ATTRIBUTE	0
228  #define ECAG_CPU_ATTRIBUTE	1
229  
__ecag(unsigned int asi,unsigned char parm)230  static inline unsigned long __ecag(unsigned int asi, unsigned char parm)
231  {
232  	unsigned long val;
233  
234  	asm volatile(".insn	rsy,0xeb000000004c,%0,0,0(%1)" /* ecag */
235  		     : "=d" (val) : "a" (asi << 8 | parm));
236  	return val;
237  }
238  
psw_set_key(unsigned int key)239  static inline void psw_set_key(unsigned int key)
240  {
241  	asm volatile("spka 0(%0)" : : "d" (key));
242  }
243  
244  /*
245   * Set PSW to specified value.
246   */
__load_psw(psw_t psw)247  static inline void __load_psw(psw_t psw)
248  {
249  	asm volatile("lpswe %0" : : "Q" (psw) : "cc");
250  }
251  
252  /*
253   * Set PSW mask to specified value, while leaving the
254   * PSW addr pointing to the next instruction.
255   */
__load_psw_mask(unsigned long mask)256  static __no_kasan_or_inline void __load_psw_mask(unsigned long mask)
257  {
258  	unsigned long addr;
259  	psw_t psw;
260  
261  	psw.mask = mask;
262  
263  	asm volatile(
264  		"	larl	%0,1f\n"
265  		"	stg	%0,%1\n"
266  		"	lpswe	%2\n"
267  		"1:"
268  		: "=&d" (addr), "=Q" (psw.addr) : "Q" (psw) : "memory", "cc");
269  }
270  
271  /*
272   * Extract current PSW mask
273   */
__extract_psw(void)274  static inline unsigned long __extract_psw(void)
275  {
276  	unsigned int reg1, reg2;
277  
278  	asm volatile("epsw %0,%1" : "=d" (reg1), "=a" (reg2));
279  	return (((unsigned long) reg1) << 32) | ((unsigned long) reg2);
280  }
281  
local_mcck_enable(void)282  static inline void local_mcck_enable(void)
283  {
284  	__load_psw_mask(__extract_psw() | PSW_MASK_MCHECK);
285  }
286  
local_mcck_disable(void)287  static inline void local_mcck_disable(void)
288  {
289  	__load_psw_mask(__extract_psw() & ~PSW_MASK_MCHECK);
290  }
291  
292  /*
293   * Rewind PSW instruction address by specified number of bytes.
294   */
__rewind_psw(psw_t psw,unsigned long ilc)295  static inline unsigned long __rewind_psw(psw_t psw, unsigned long ilc)
296  {
297  	unsigned long mask;
298  
299  	mask = (psw.mask & PSW_MASK_EA) ? -1UL :
300  	       (psw.mask & PSW_MASK_BA) ? (1UL << 31) - 1 :
301  					  (1UL << 24) - 1;
302  	return (psw.addr - ilc) & mask;
303  }
304  
305  /*
306   * Function to stop a processor until the next interrupt occurs
307   */
308  void enabled_wait(void);
309  
310  /*
311   * Function to drop a processor into disabled wait state
312   */
disabled_wait(void)313  static inline void __noreturn disabled_wait(void)
314  {
315  	psw_t psw;
316  
317  	psw.mask = PSW_MASK_BASE | PSW_MASK_WAIT | PSW_MASK_BA | PSW_MASK_EA;
318  	psw.addr = _THIS_IP_;
319  	__load_psw(psw);
320  	while (1);
321  }
322  
323  /*
324   * Basic Machine Check/Program Check Handler.
325   */
326  
327  extern void s390_base_pgm_handler(void);
328  extern void s390_base_ext_handler(void);
329  
330  extern void (*s390_base_pgm_handler_fn)(void);
331  extern void (*s390_base_ext_handler_fn)(void);
332  
333  #define ARCH_LOW_ADDRESS_LIMIT	0x7fffffffUL
334  
335  extern int memcpy_real(void *, void *, size_t);
336  extern void memcpy_absolute(void *, void *, size_t);
337  
338  #define mem_assign_absolute(dest, val) do {			\
339  	__typeof__(dest) __tmp = (val);				\
340  								\
341  	BUILD_BUG_ON(sizeof(__tmp) != sizeof(val));		\
342  	memcpy_absolute(&(dest), &__tmp, sizeof(__tmp));	\
343  } while (0)
344  
345  extern int s390_isolate_bp(void);
346  extern int s390_isolate_bp_guest(void);
347  
348  #endif /* __ASSEMBLY__ */
349  
350  #endif /* __ASM_S390_PROCESSOR_H */
351