xref: /openbmc/linux/arch/s390/include/asm/processor.h (revision 77a87824)
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 	mm_segment_t mm_segment;
114 	unsigned long gmap_addr;	/* address of last gmap fault. */
115 	unsigned int gmap_pfault;	/* signal of a pending guest pfault */
116 	struct per_regs per_user;	/* User specified PER registers */
117 	struct per_event per_event;	/* Cause of the last PER trap */
118 	unsigned long per_flags;	/* Flags to control debug behavior */
119         /* pfault_wait is used to block the process on a pfault event */
120 	unsigned long pfault_wait;
121 	struct list_head list;
122 	/* cpu runtime instrumentation */
123 	struct runtime_instr_cb *ri_cb;
124 	unsigned char trap_tdb[256];	/* Transaction abort diagnose block */
125 	/*
126 	 * Warning: 'fpu' is dynamically-sized. It *MUST* be at
127 	 * the end.
128 	 */
129 	struct fpu fpu;			/* FP and VX register save area */
130 };
131 
132 /* Flag to disable transactions. */
133 #define PER_FLAG_NO_TE			1UL
134 /* Flag to enable random transaction aborts. */
135 #define PER_FLAG_TE_ABORT_RAND		2UL
136 /* Flag to specify random transaction abort mode:
137  * - abort each transaction at a random instruction before TEND if set.
138  * - abort random transactions at a random instruction if cleared.
139  */
140 #define PER_FLAG_TE_ABORT_RAND_TEND	4UL
141 
142 typedef struct thread_struct thread_struct;
143 
144 /*
145  * Stack layout of a C stack frame.
146  */
147 #ifndef __PACK_STACK
148 struct stack_frame {
149 	unsigned long back_chain;
150 	unsigned long empty1[5];
151 	unsigned long gprs[10];
152 	unsigned int  empty2[8];
153 };
154 #else
155 struct stack_frame {
156 	unsigned long empty1[5];
157 	unsigned int  empty2[8];
158 	unsigned long gprs[10];
159 	unsigned long back_chain;
160 };
161 #endif
162 
163 #define ARCH_MIN_TASKALIGN	8
164 
165 #define INIT_THREAD {							\
166 	.ksp = sizeof(init_stack) + (unsigned long) &init_stack,	\
167 	.fpu.regs = (void *) init_task.thread.fpu.fprs,			\
168 }
169 
170 /*
171  * Do necessary setup to start up a new thread.
172  */
173 #define start_thread(regs, new_psw, new_stackp) do {			\
174 	regs->psw.mask	= PSW_USER_BITS | PSW_MASK_EA | PSW_MASK_BA;	\
175 	regs->psw.addr	= new_psw;					\
176 	regs->gprs[15]	= new_stackp;					\
177 	execve_tail();							\
178 } while (0)
179 
180 #define start_thread31(regs, new_psw, new_stackp) do {			\
181 	regs->psw.mask	= PSW_USER_BITS | PSW_MASK_BA;			\
182 	regs->psw.addr	= new_psw;					\
183 	regs->gprs[15]	= new_stackp;					\
184 	crst_table_downgrade(current->mm);				\
185 	execve_tail();							\
186 } while (0)
187 
188 /* Forward declaration, a strange C thing */
189 struct task_struct;
190 struct mm_struct;
191 struct seq_file;
192 
193 typedef int (*dump_trace_func_t)(void *data, unsigned long address);
194 void dump_trace(dump_trace_func_t func, void *data,
195 		struct task_struct *task, unsigned long sp);
196 
197 void show_cacheinfo(struct seq_file *m);
198 
199 /* Free all resources held by a thread. */
200 extern void release_thread(struct task_struct *);
201 
202 /*
203  * Return saved PC of a blocked thread.
204  */
205 extern unsigned long thread_saved_pc(struct task_struct *t);
206 
207 unsigned long get_wchan(struct task_struct *p);
208 #define task_pt_regs(tsk) ((struct pt_regs *) \
209         (task_stack_page(tsk) + THREAD_SIZE) - 1)
210 #define KSTK_EIP(tsk)	(task_pt_regs(tsk)->psw.addr)
211 #define KSTK_ESP(tsk)	(task_pt_regs(tsk)->gprs[15])
212 
213 /* Has task runtime instrumentation enabled ? */
214 #define is_ri_task(tsk) (!!(tsk)->thread.ri_cb)
215 
216 static inline unsigned long current_stack_pointer(void)
217 {
218 	unsigned long sp;
219 
220 	asm volatile("la %0,0(15)" : "=a" (sp));
221 	return sp;
222 }
223 
224 static inline unsigned short stap(void)
225 {
226 	unsigned short cpu_address;
227 
228 	asm volatile("stap %0" : "=m" (cpu_address));
229 	return cpu_address;
230 }
231 
232 /*
233  * Give up the time slice of the virtual PU.
234  */
235 void cpu_relax(void);
236 
237 #define cpu_relax_lowlatency()  barrier()
238 
239 #define ECAG_CACHE_ATTRIBUTE	0
240 #define ECAG_CPU_ATTRIBUTE	1
241 
242 static inline unsigned long __ecag(unsigned int asi, unsigned char parm)
243 {
244 	unsigned long val;
245 
246 	asm volatile(".insn	rsy,0xeb000000004c,%0,0,0(%1)" /* ecag */
247 		     : "=d" (val) : "a" (asi << 8 | parm));
248 	return val;
249 }
250 
251 static inline void psw_set_key(unsigned int key)
252 {
253 	asm volatile("spka 0(%0)" : : "d" (key));
254 }
255 
256 /*
257  * Set PSW to specified value.
258  */
259 static inline void __load_psw(psw_t psw)
260 {
261 	asm volatile("lpswe %0" : : "Q" (psw) : "cc");
262 }
263 
264 /*
265  * Set PSW mask to specified value, while leaving the
266  * PSW addr pointing to the next instruction.
267  */
268 static inline void __load_psw_mask(unsigned long mask)
269 {
270 	unsigned long addr;
271 	psw_t psw;
272 
273 	psw.mask = mask;
274 
275 	asm volatile(
276 		"	larl	%0,1f\n"
277 		"	stg	%0,%O1+8(%R1)\n"
278 		"	lpswe	%1\n"
279 		"1:"
280 		: "=&d" (addr), "=Q" (psw) : "Q" (psw) : "memory", "cc");
281 }
282 
283 /*
284  * Extract current PSW mask
285  */
286 static inline unsigned long __extract_psw(void)
287 {
288 	unsigned int reg1, reg2;
289 
290 	asm volatile("epsw %0,%1" : "=d" (reg1), "=a" (reg2));
291 	return (((unsigned long) reg1) << 32) | ((unsigned long) reg2);
292 }
293 
294 static inline void local_mcck_enable(void)
295 {
296 	__load_psw_mask(__extract_psw() | PSW_MASK_MCHECK);
297 }
298 
299 static inline void local_mcck_disable(void)
300 {
301 	__load_psw_mask(__extract_psw() & ~PSW_MASK_MCHECK);
302 }
303 
304 /*
305  * Rewind PSW instruction address by specified number of bytes.
306  */
307 static inline unsigned long __rewind_psw(psw_t psw, unsigned long ilc)
308 {
309 	unsigned long mask;
310 
311 	mask = (psw.mask & PSW_MASK_EA) ? -1UL :
312 	       (psw.mask & PSW_MASK_BA) ? (1UL << 31) - 1 :
313 					  (1UL << 24) - 1;
314 	return (psw.addr - ilc) & mask;
315 }
316 
317 /*
318  * Function to stop a processor until the next interrupt occurs
319  */
320 void enabled_wait(void);
321 
322 /*
323  * Function to drop a processor into disabled wait state
324  */
325 static inline void __noreturn disabled_wait(unsigned long code)
326 {
327 	psw_t psw;
328 
329 	psw.mask = PSW_MASK_BASE | PSW_MASK_WAIT | PSW_MASK_BA | PSW_MASK_EA;
330 	psw.addr = code;
331 	__load_psw(psw);
332 	while (1);
333 }
334 
335 /*
336  * Basic Machine Check/Program Check Handler.
337  */
338 
339 extern void s390_base_mcck_handler(void);
340 extern void s390_base_pgm_handler(void);
341 extern void s390_base_ext_handler(void);
342 
343 extern void (*s390_base_mcck_handler_fn)(void);
344 extern void (*s390_base_pgm_handler_fn)(void);
345 extern void (*s390_base_ext_handler_fn)(void);
346 
347 #define ARCH_LOW_ADDRESS_LIMIT	0x7fffffffUL
348 
349 extern int memcpy_real(void *, void *, size_t);
350 extern void memcpy_absolute(void *, void *, size_t);
351 
352 #define mem_assign_absolute(dest, val) {			\
353 	__typeof__(dest) __tmp = (val);				\
354 								\
355 	BUILD_BUG_ON(sizeof(__tmp) != sizeof(val));		\
356 	memcpy_absolute(&(dest), &__tmp, sizeof(__tmp));	\
357 }
358 
359 #endif /* __ASSEMBLY__ */
360 
361 #endif /* __ASM_S390_PROCESSOR_H */
362