xref: /linux/arch/s390/include/asm/processor.h (revision 0883c2c06fb5bcf5b9e008270827e63c09a88c1e)
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 extern void s390_adjust_jiffies(void);
81 extern const struct seq_operations cpuinfo_op;
82 extern int sysctl_ieee_emulation_warnings;
83 extern void execve_tail(void);
84 
85 /*
86  * User space process size: 2GB for 31 bit, 4TB or 8PT for 64 bit.
87  */
88 
89 #define TASK_SIZE_OF(tsk)	((tsk)->mm->context.asce_limit)
90 #define TASK_UNMAPPED_BASE	(test_thread_flag(TIF_31BIT) ? \
91 					(1UL << 30) : (1UL << 41))
92 #define TASK_SIZE		TASK_SIZE_OF(current)
93 #define TASK_MAX_SIZE		(1UL << 53)
94 
95 #define STACK_TOP		(1UL << (test_thread_flag(TIF_31BIT) ? 31:42))
96 #define STACK_TOP_MAX		(1UL << 42)
97 
98 #define HAVE_ARCH_PICK_MMAP_LAYOUT
99 
100 typedef struct {
101         __u32 ar4;
102 } mm_segment_t;
103 
104 /*
105  * Thread structure
106  */
107 struct thread_struct {
108 	unsigned int  acrs[NUM_ACRS];
109         unsigned long ksp;              /* kernel stack pointer             */
110 	mm_segment_t mm_segment;
111 	unsigned long gmap_addr;	/* address of last gmap fault. */
112 	unsigned int gmap_pfault;	/* signal of a pending guest pfault */
113 	struct per_regs per_user;	/* User specified PER registers */
114 	struct per_event per_event;	/* Cause of the last PER trap */
115 	unsigned long per_flags;	/* Flags to control debug behavior */
116         /* pfault_wait is used to block the process on a pfault event */
117 	unsigned long pfault_wait;
118 	struct list_head list;
119 	/* cpu runtime instrumentation */
120 	struct runtime_instr_cb *ri_cb;
121 	unsigned char trap_tdb[256];	/* Transaction abort diagnose block */
122 	/*
123 	 * Warning: 'fpu' is dynamically-sized. It *MUST* be at
124 	 * the end.
125 	 */
126 	struct fpu fpu;			/* FP and VX register save area */
127 };
128 
129 /* Flag to disable transactions. */
130 #define PER_FLAG_NO_TE			1UL
131 /* Flag to enable random transaction aborts. */
132 #define PER_FLAG_TE_ABORT_RAND		2UL
133 /* Flag to specify random transaction abort mode:
134  * - abort each transaction at a random instruction before TEND if set.
135  * - abort random transactions at a random instruction if cleared.
136  */
137 #define PER_FLAG_TE_ABORT_RAND_TEND	4UL
138 
139 typedef struct thread_struct thread_struct;
140 
141 /*
142  * Stack layout of a C stack frame.
143  */
144 #ifndef __PACK_STACK
145 struct stack_frame {
146 	unsigned long back_chain;
147 	unsigned long empty1[5];
148 	unsigned long gprs[10];
149 	unsigned int  empty2[8];
150 };
151 #else
152 struct stack_frame {
153 	unsigned long empty1[5];
154 	unsigned int  empty2[8];
155 	unsigned long gprs[10];
156 	unsigned long back_chain;
157 };
158 #endif
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 
190 typedef int (*dump_trace_func_t)(void *data, unsigned long address);
191 void dump_trace(dump_trace_func_t func, void *data,
192 		struct task_struct *task, unsigned long sp);
193 
194 void show_cacheinfo(struct seq_file *m);
195 
196 /* Free all resources held by a thread. */
197 extern void release_thread(struct task_struct *);
198 
199 /*
200  * Return saved PC of a blocked thread.
201  */
202 extern unsigned long thread_saved_pc(struct task_struct *t);
203 
204 unsigned long get_wchan(struct task_struct *p);
205 #define task_pt_regs(tsk) ((struct pt_regs *) \
206         (task_stack_page(tsk) + THREAD_SIZE) - 1)
207 #define KSTK_EIP(tsk)	(task_pt_regs(tsk)->psw.addr)
208 #define KSTK_ESP(tsk)	(task_pt_regs(tsk)->gprs[15])
209 
210 /* Has task runtime instrumentation enabled ? */
211 #define is_ri_task(tsk) (!!(tsk)->thread.ri_cb)
212 
213 static inline unsigned long current_stack_pointer(void)
214 {
215 	unsigned long sp;
216 
217 	asm volatile("la %0,0(15)" : "=a" (sp));
218 	return sp;
219 }
220 
221 static inline unsigned short stap(void)
222 {
223 	unsigned short cpu_address;
224 
225 	asm volatile("stap %0" : "=m" (cpu_address));
226 	return cpu_address;
227 }
228 
229 /*
230  * Give up the time slice of the virtual PU.
231  */
232 void cpu_relax(void);
233 
234 #define cpu_relax_lowlatency()  barrier()
235 
236 static inline void psw_set_key(unsigned int key)
237 {
238 	asm volatile("spka 0(%0)" : : "d" (key));
239 }
240 
241 /*
242  * Set PSW to specified value.
243  */
244 static inline void __load_psw(psw_t psw)
245 {
246 	asm volatile("lpswe %0" : : "Q" (psw) : "cc");
247 }
248 
249 /*
250  * Set PSW mask to specified value, while leaving the
251  * PSW addr pointing to the next instruction.
252  */
253 static inline void __load_psw_mask(unsigned long mask)
254 {
255 	unsigned long addr;
256 	psw_t psw;
257 
258 	psw.mask = mask;
259 
260 	asm volatile(
261 		"	larl	%0,1f\n"
262 		"	stg	%0,%O1+8(%R1)\n"
263 		"	lpswe	%1\n"
264 		"1:"
265 		: "=&d" (addr), "=Q" (psw) : "Q" (psw) : "memory", "cc");
266 }
267 
268 /*
269  * Extract current PSW mask
270  */
271 static inline unsigned long __extract_psw(void)
272 {
273 	unsigned int reg1, reg2;
274 
275 	asm volatile("epsw %0,%1" : "=d" (reg1), "=a" (reg2));
276 	return (((unsigned long) reg1) << 32) | ((unsigned long) reg2);
277 }
278 
279 static inline void local_mcck_enable(void)
280 {
281 	__load_psw_mask(__extract_psw() | PSW_MASK_MCHECK);
282 }
283 
284 static inline void local_mcck_disable(void)
285 {
286 	__load_psw_mask(__extract_psw() & ~PSW_MASK_MCHECK);
287 }
288 
289 /*
290  * Rewind PSW instruction address by specified number of bytes.
291  */
292 static inline unsigned long __rewind_psw(psw_t psw, unsigned long ilc)
293 {
294 	unsigned long mask;
295 
296 	mask = (psw.mask & PSW_MASK_EA) ? -1UL :
297 	       (psw.mask & PSW_MASK_BA) ? (1UL << 31) - 1 :
298 					  (1UL << 24) - 1;
299 	return (psw.addr - ilc) & mask;
300 }
301 
302 /*
303  * Function to stop a processor until the next interrupt occurs
304  */
305 void enabled_wait(void);
306 
307 /*
308  * Function to drop a processor into disabled wait state
309  */
310 static inline void __noreturn disabled_wait(unsigned long code)
311 {
312 	psw_t psw;
313 
314 	psw.mask = PSW_MASK_BASE | PSW_MASK_WAIT | PSW_MASK_BA | PSW_MASK_EA;
315 	psw.addr = code;
316 	__load_psw(psw);
317 	while (1);
318 }
319 
320 /*
321  * Basic Machine Check/Program Check Handler.
322  */
323 
324 extern void s390_base_mcck_handler(void);
325 extern void s390_base_pgm_handler(void);
326 extern void s390_base_ext_handler(void);
327 
328 extern void (*s390_base_mcck_handler_fn)(void);
329 extern void (*s390_base_pgm_handler_fn)(void);
330 extern void (*s390_base_ext_handler_fn)(void);
331 
332 #define ARCH_LOW_ADDRESS_LIMIT	0x7fffffffUL
333 
334 extern int memcpy_real(void *, void *, size_t);
335 extern void memcpy_absolute(void *, void *, size_t);
336 
337 #define mem_assign_absolute(dest, val) {			\
338 	__typeof__(dest) __tmp = (val);				\
339 								\
340 	BUILD_BUG_ON(sizeof(__tmp) != sizeof(val));		\
341 	memcpy_absolute(&(dest), &__tmp, sizeof(__tmp));	\
342 }
343 
344 #endif /* __ASSEMBLY__ */
345 
346 #endif /* __ASM_S390_PROCESSOR_H */
347