xref: /openbmc/linux/arch/s390/include/asm/processor.h (revision 7bcae826)
1 /*
2  *  S390 version
3  *    Copyright IBM Corp. 1999
4  *    Author(s): Hartmut Penner (hp@de.ibm.com),
5  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
6  *
7  *  Derived from "include/asm-i386/processor.h"
8  *    Copyright (C) 1994, Linus Torvalds
9  */
10 
11 #ifndef __ASM_S390_PROCESSOR_H
12 #define __ASM_S390_PROCESSOR_H
13 
14 #include <linux/const.h>
15 
16 #define CIF_MCCK_PENDING	0	/* machine check handling is pending */
17 #define CIF_ASCE		1	/* user asce needs fixup / uaccess */
18 #define CIF_NOHZ_DELAY		2	/* delay HZ disable for a tick */
19 #define CIF_FPU			3	/* restore FPU registers */
20 #define CIF_IGNORE_IRQ		4	/* ignore interrupt (for udelay) */
21 #define CIF_ENABLED_WAIT	5	/* in enabled wait state */
22 
23 #define _CIF_MCCK_PENDING	_BITUL(CIF_MCCK_PENDING)
24 #define _CIF_ASCE		_BITUL(CIF_ASCE)
25 #define _CIF_NOHZ_DELAY		_BITUL(CIF_NOHZ_DELAY)
26 #define _CIF_FPU		_BITUL(CIF_FPU)
27 #define _CIF_IGNORE_IRQ		_BITUL(CIF_IGNORE_IRQ)
28 #define _CIF_ENABLED_WAIT	_BITUL(CIF_ENABLED_WAIT)
29 
30 #ifndef __ASSEMBLY__
31 
32 #include <linux/linkage.h>
33 #include <linux/irqflags.h>
34 #include <asm/cpu.h>
35 #include <asm/page.h>
36 #include <asm/ptrace.h>
37 #include <asm/setup.h>
38 #include <asm/runtime_instr.h>
39 #include <asm/fpu/types.h>
40 #include <asm/fpu/internal.h>
41 
42 static inline void set_cpu_flag(int flag)
43 {
44 	S390_lowcore.cpu_flags |= (1UL << flag);
45 }
46 
47 static inline void clear_cpu_flag(int flag)
48 {
49 	S390_lowcore.cpu_flags &= ~(1UL << flag);
50 }
51 
52 static inline int test_cpu_flag(int flag)
53 {
54 	return !!(S390_lowcore.cpu_flags & (1UL << flag));
55 }
56 
57 /*
58  * Test CIF flag of another CPU. The caller needs to ensure that
59  * CPU hotplug can not happen, e.g. by disabling preemption.
60  */
61 static inline int test_cpu_flag_of(int flag, int cpu)
62 {
63 	struct lowcore *lc = lowcore_ptr[cpu];
64 	return !!(lc->cpu_flags & (1UL << flag));
65 }
66 
67 #define arch_needs_cpu() test_cpu_flag(CIF_NOHZ_DELAY)
68 
69 /*
70  * Default implementation of macro that returns current
71  * instruction pointer ("program counter").
72  */
73 #define current_text_addr() ({ void *pc; asm("basr %0,0" : "=a" (pc)); pc; })
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 int sysctl_ieee_emulation_warnings;
86 extern void execve_tail(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)	((tsk)->mm->context.asce_limit)
93 #define TASK_UNMAPPED_BASE	(test_thread_flag(TIF_31BIT) ? \
94 					(1UL << 30) : (1UL << 41))
95 #define TASK_SIZE		TASK_SIZE_OF(current)
96 #define TASK_MAX_SIZE		(1UL << 53)
97 
98 #define STACK_TOP		(1UL << (test_thread_flag(TIF_31BIT) ? 31:42))
99 #define STACK_TOP_MAX		(1UL << 42)
100 
101 #define HAVE_ARCH_PICK_MMAP_LAYOUT
102 
103 typedef struct {
104         __u32 ar4;
105 } 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 	unsigned char trap_tdb[256];	/* 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 /*
156  * Stack layout of a C stack frame.
157  */
158 #ifndef __PACK_STACK
159 struct stack_frame {
160 	unsigned long back_chain;
161 	unsigned long empty1[5];
162 	unsigned long gprs[10];
163 	unsigned int  empty2[8];
164 };
165 #else
166 struct stack_frame {
167 	unsigned long empty1[5];
168 	unsigned int  empty2[8];
169 	unsigned long gprs[10];
170 	unsigned long back_chain;
171 };
172 #endif
173 
174 #define ARCH_MIN_TASKALIGN	8
175 
176 #define INIT_THREAD {							\
177 	.ksp = sizeof(init_stack) + (unsigned long) &init_stack,	\
178 	.fpu.regs = (void *) init_task.thread.fpu.fprs,			\
179 }
180 
181 /*
182  * Do necessary setup to start up a new thread.
183  */
184 #define start_thread(regs, new_psw, new_stackp) do {			\
185 	regs->psw.mask	= PSW_USER_BITS | PSW_MASK_EA | PSW_MASK_BA;	\
186 	regs->psw.addr	= new_psw;					\
187 	regs->gprs[15]	= new_stackp;					\
188 	execve_tail();							\
189 } while (0)
190 
191 #define start_thread31(regs, new_psw, new_stackp) do {			\
192 	regs->psw.mask	= PSW_USER_BITS | PSW_MASK_BA;			\
193 	regs->psw.addr	= new_psw;					\
194 	regs->gprs[15]	= new_stackp;					\
195 	crst_table_downgrade(current->mm);				\
196 	execve_tail();							\
197 } while (0)
198 
199 /* Forward declaration, a strange C thing */
200 struct task_struct;
201 struct mm_struct;
202 struct seq_file;
203 
204 typedef int (*dump_trace_func_t)(void *data, unsigned long address, int reliable);
205 void dump_trace(dump_trace_func_t func, void *data,
206 		struct task_struct *task, unsigned long sp);
207 
208 void show_cacheinfo(struct seq_file *m);
209 
210 /* Free all resources held by a thread. */
211 extern void release_thread(struct task_struct *);
212 
213 /*
214  * Return saved PC of a blocked thread.
215  */
216 extern unsigned long thread_saved_pc(struct task_struct *t);
217 
218 unsigned long get_wchan(struct task_struct *p);
219 #define task_pt_regs(tsk) ((struct pt_regs *) \
220         (task_stack_page(tsk) + THREAD_SIZE) - 1)
221 #define KSTK_EIP(tsk)	(task_pt_regs(tsk)->psw.addr)
222 #define KSTK_ESP(tsk)	(task_pt_regs(tsk)->gprs[15])
223 
224 /* Has task runtime instrumentation enabled ? */
225 #define is_ri_task(tsk) (!!(tsk)->thread.ri_cb)
226 
227 static inline unsigned long current_stack_pointer(void)
228 {
229 	unsigned long sp;
230 
231 	asm volatile("la %0,0(15)" : "=a" (sp));
232 	return sp;
233 }
234 
235 static inline unsigned short stap(void)
236 {
237 	unsigned short cpu_address;
238 
239 	asm volatile("stap %0" : "=m" (cpu_address));
240 	return cpu_address;
241 }
242 
243 /*
244  * Give up the time slice of the virtual PU.
245  */
246 #define cpu_relax_yield cpu_relax_yield
247 void cpu_relax_yield(void);
248 
249 #define cpu_relax() barrier()
250 
251 #define ECAG_CACHE_ATTRIBUTE	0
252 #define ECAG_CPU_ATTRIBUTE	1
253 
254 static inline unsigned long __ecag(unsigned int asi, unsigned char parm)
255 {
256 	unsigned long val;
257 
258 	asm volatile(".insn	rsy,0xeb000000004c,%0,0,0(%1)" /* ecag */
259 		     : "=d" (val) : "a" (asi << 8 | parm));
260 	return val;
261 }
262 
263 static inline void psw_set_key(unsigned int key)
264 {
265 	asm volatile("spka 0(%0)" : : "d" (key));
266 }
267 
268 /*
269  * Set PSW to specified value.
270  */
271 static inline void __load_psw(psw_t psw)
272 {
273 	asm volatile("lpswe %0" : : "Q" (psw) : "cc");
274 }
275 
276 /*
277  * Set PSW mask to specified value, while leaving the
278  * PSW addr pointing to the next instruction.
279  */
280 static inline void __load_psw_mask(unsigned long mask)
281 {
282 	unsigned long addr;
283 	psw_t psw;
284 
285 	psw.mask = mask;
286 
287 	asm volatile(
288 		"	larl	%0,1f\n"
289 		"	stg	%0,%O1+8(%R1)\n"
290 		"	lpswe	%1\n"
291 		"1:"
292 		: "=&d" (addr), "=Q" (psw) : "Q" (psw) : "memory", "cc");
293 }
294 
295 /*
296  * Extract current PSW mask
297  */
298 static inline unsigned long __extract_psw(void)
299 {
300 	unsigned int reg1, reg2;
301 
302 	asm volatile("epsw %0,%1" : "=d" (reg1), "=a" (reg2));
303 	return (((unsigned long) reg1) << 32) | ((unsigned long) reg2);
304 }
305 
306 static inline void local_mcck_enable(void)
307 {
308 	__load_psw_mask(__extract_psw() | PSW_MASK_MCHECK);
309 }
310 
311 static inline void local_mcck_disable(void)
312 {
313 	__load_psw_mask(__extract_psw() & ~PSW_MASK_MCHECK);
314 }
315 
316 /*
317  * Rewind PSW instruction address by specified number of bytes.
318  */
319 static inline unsigned long __rewind_psw(psw_t psw, unsigned long ilc)
320 {
321 	unsigned long mask;
322 
323 	mask = (psw.mask & PSW_MASK_EA) ? -1UL :
324 	       (psw.mask & PSW_MASK_BA) ? (1UL << 31) - 1 :
325 					  (1UL << 24) - 1;
326 	return (psw.addr - ilc) & mask;
327 }
328 
329 /*
330  * Function to stop a processor until the next interrupt occurs
331  */
332 void enabled_wait(void);
333 
334 /*
335  * Function to drop a processor into disabled wait state
336  */
337 static inline void __noreturn disabled_wait(unsigned long code)
338 {
339 	psw_t psw;
340 
341 	psw.mask = PSW_MASK_BASE | PSW_MASK_WAIT | PSW_MASK_BA | PSW_MASK_EA;
342 	psw.addr = code;
343 	__load_psw(psw);
344 	while (1);
345 }
346 
347 /*
348  * Basic Machine Check/Program Check Handler.
349  */
350 
351 extern void s390_base_mcck_handler(void);
352 extern void s390_base_pgm_handler(void);
353 extern void s390_base_ext_handler(void);
354 
355 extern void (*s390_base_mcck_handler_fn)(void);
356 extern void (*s390_base_pgm_handler_fn)(void);
357 extern void (*s390_base_ext_handler_fn)(void);
358 
359 #define ARCH_LOW_ADDRESS_LIMIT	0x7fffffffUL
360 
361 extern int memcpy_real(void *, void *, size_t);
362 extern void memcpy_absolute(void *, void *, size_t);
363 
364 #define mem_assign_absolute(dest, val) do {			\
365 	__typeof__(dest) __tmp = (val);				\
366 								\
367 	BUILD_BUG_ON(sizeof(__tmp) != sizeof(val));		\
368 	memcpy_absolute(&(dest), &__tmp, sizeof(__tmp));	\
369 } while (0)
370 
371 #endif /* __ASSEMBLY__ */
372 
373 #endif /* __ASM_S390_PROCESSOR_H */
374