xref: /openbmc/linux/arch/s390/include/asm/processor.h (revision b627b4ed)
1 /*
2  *  include/asm-s390/processor.h
3  *
4  *  S390 version
5  *    Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
6  *    Author(s): Hartmut Penner (hp@de.ibm.com),
7  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
8  *
9  *  Derived from "include/asm-i386/processor.h"
10  *    Copyright (C) 1994, Linus Torvalds
11  */
12 
13 #ifndef __ASM_S390_PROCESSOR_H
14 #define __ASM_S390_PROCESSOR_H
15 
16 #include <linux/linkage.h>
17 #include <asm/ptrace.h>
18 
19 #ifdef __KERNEL__
20 /*
21  * Default implementation of macro that returns current
22  * instruction pointer ("program counter").
23  */
24 #define current_text_addr() ({ void *pc; asm("basr %0,0" : "=a" (pc)); pc; })
25 
26 /*
27  *  CPU type and hardware bug flags. Kept separately for each CPU.
28  *  Members of this structure are referenced in head.S, so think twice
29  *  before touching them. [mj]
30  */
31 
32 typedef struct
33 {
34         unsigned int version :  8;
35         unsigned int ident   : 24;
36         unsigned int machine : 16;
37         unsigned int unused  : 16;
38 } __attribute__ ((packed)) cpuid_t;
39 
40 static inline void get_cpu_id(cpuid_t *ptr)
41 {
42 	asm volatile("stidp 0(%1)" : "=m" (*ptr) : "a" (ptr));
43 }
44 
45 extern void s390_adjust_jiffies(void);
46 extern void print_cpu_info(void);
47 extern int get_cpu_capability(unsigned int *);
48 
49 /*
50  * User space process size: 2GB for 31 bit, 4TB or 8PT for 64 bit.
51  */
52 #ifndef __s390x__
53 
54 #define TASK_SIZE		(1UL << 31)
55 #define TASK_UNMAPPED_BASE	(1UL << 30)
56 
57 #else /* __s390x__ */
58 
59 #define TASK_SIZE_OF(tsk)	((tsk)->mm->context.asce_limit)
60 #define TASK_UNMAPPED_BASE	(test_thread_flag(TIF_31BIT) ? \
61 					(1UL << 30) : (1UL << 41))
62 #define TASK_SIZE		TASK_SIZE_OF(current)
63 
64 #endif /* __s390x__ */
65 
66 #ifdef __KERNEL__
67 
68 #ifndef __s390x__
69 #define STACK_TOP		(1UL << 31)
70 #define STACK_TOP_MAX		(1UL << 31)
71 #else /* __s390x__ */
72 #define STACK_TOP		(1UL << (test_thread_flag(TIF_31BIT) ? 31:42))
73 #define STACK_TOP_MAX		(1UL << 42)
74 #endif /* __s390x__ */
75 
76 
77 #endif
78 
79 #define HAVE_ARCH_PICK_MMAP_LAYOUT
80 
81 typedef struct {
82         __u32 ar4;
83 } mm_segment_t;
84 
85 /*
86  * Thread structure
87  */
88 struct thread_struct {
89 	s390_fp_regs fp_regs;
90 	unsigned int  acrs[NUM_ACRS];
91         unsigned long ksp;              /* kernel stack pointer             */
92 	mm_segment_t mm_segment;
93         unsigned long prot_addr;        /* address of protection-excep.     */
94         unsigned int trap_no;
95         per_struct per_info;
96 	/* Used to give failing instruction back to user for ieee exceptions */
97 	unsigned long ieee_instruction_pointer;
98         /* pfault_wait is used to block the process on a pfault event */
99 	unsigned long pfault_wait;
100 };
101 
102 typedef struct thread_struct thread_struct;
103 
104 /*
105  * Stack layout of a C stack frame.
106  */
107 #ifndef __PACK_STACK
108 struct stack_frame {
109 	unsigned long back_chain;
110 	unsigned long empty1[5];
111 	unsigned long gprs[10];
112 	unsigned int  empty2[8];
113 };
114 #else
115 struct stack_frame {
116 	unsigned long empty1[5];
117 	unsigned int  empty2[8];
118 	unsigned long gprs[10];
119 	unsigned long back_chain;
120 };
121 #endif
122 
123 #define ARCH_MIN_TASKALIGN	8
124 
125 #define INIT_THREAD {							\
126 	.ksp = sizeof(init_stack) + (unsigned long) &init_stack,	\
127 }
128 
129 /*
130  * Do necessary setup to start up a new thread.
131  */
132 #define start_thread(regs, new_psw, new_stackp) do {		\
133 	set_fs(USER_DS);					\
134 	regs->psw.mask	= psw_user_bits;			\
135 	regs->psw.addr	= new_psw | PSW_ADDR_AMODE;		\
136 	regs->gprs[15]	= new_stackp;				\
137 } while (0)
138 
139 #define start_thread31(regs, new_psw, new_stackp) do {		\
140 	set_fs(USER_DS);					\
141 	regs->psw.mask	= psw_user32_bits;			\
142 	regs->psw.addr	= new_psw | PSW_ADDR_AMODE;		\
143 	regs->gprs[15]	= new_stackp;				\
144 	crst_table_downgrade(current->mm, 1UL << 31);		\
145 } while (0)
146 
147 /* Forward declaration, a strange C thing */
148 struct task_struct;
149 struct mm_struct;
150 struct seq_file;
151 
152 /* Free all resources held by a thread. */
153 extern void release_thread(struct task_struct *);
154 extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
155 
156 /* Prepare to copy thread state - unlazy all lazy status */
157 #define prepare_to_copy(tsk)	do { } while (0)
158 
159 /*
160  * Return saved PC of a blocked thread.
161  */
162 extern unsigned long thread_saved_pc(struct task_struct *t);
163 
164 /*
165  * Print register of task into buffer. Used in fs/proc/array.c.
166  */
167 extern void task_show_regs(struct seq_file *m, struct task_struct *task);
168 
169 extern void show_code(struct pt_regs *regs);
170 
171 unsigned long get_wchan(struct task_struct *p);
172 #define task_pt_regs(tsk) ((struct pt_regs *) \
173         (task_stack_page(tsk) + THREAD_SIZE) - 1)
174 #define KSTK_EIP(tsk)	(task_pt_regs(tsk)->psw.addr)
175 #define KSTK_ESP(tsk)	(task_pt_regs(tsk)->gprs[15])
176 
177 /*
178  * Give up the time slice of the virtual PU.
179  */
180 static inline void cpu_relax(void)
181 {
182 	if (MACHINE_HAS_DIAG44)
183 		asm volatile("diag 0,0,68");
184 	barrier();
185 }
186 
187 static inline void psw_set_key(unsigned int key)
188 {
189 	asm volatile("spka 0(%0)" : : "d" (key));
190 }
191 
192 /*
193  * Set PSW to specified value.
194  */
195 static inline void __load_psw(psw_t psw)
196 {
197 #ifndef __s390x__
198 	asm volatile("lpsw  0(%0)" : : "a" (&psw), "m" (psw) : "cc");
199 #else
200 	asm volatile("lpswe 0(%0)" : : "a" (&psw), "m" (psw) : "cc");
201 #endif
202 }
203 
204 /*
205  * Set PSW mask to specified value, while leaving the
206  * PSW addr pointing to the next instruction.
207  */
208 
209 static inline void __load_psw_mask (unsigned long mask)
210 {
211 	unsigned long addr;
212 	psw_t psw;
213 
214 	psw.mask = mask;
215 
216 #ifndef __s390x__
217 	asm volatile(
218 		"	basr	%0,0\n"
219 		"0:	ahi	%0,1f-0b\n"
220 		"	st	%0,4(%1)\n"
221 		"	lpsw	0(%1)\n"
222 		"1:"
223 		: "=&d" (addr) : "a" (&psw), "m" (psw) : "memory", "cc");
224 #else /* __s390x__ */
225 	asm volatile(
226 		"	larl	%0,1f\n"
227 		"	stg	%0,8(%1)\n"
228 		"	lpswe	0(%1)\n"
229 		"1:"
230 		: "=&d" (addr) : "a" (&psw), "m" (psw) : "memory", "cc");
231 #endif /* __s390x__ */
232 }
233 
234 /*
235  * Function to stop a processor until an interruption occurred
236  */
237 static inline void enabled_wait(void)
238 {
239 	__load_psw_mask(PSW_BASE_BITS | PSW_MASK_IO | PSW_MASK_EXT |
240 			PSW_MASK_MCHECK | PSW_MASK_WAIT | PSW_DEFAULT_KEY);
241 }
242 
243 /*
244  * Function to drop a processor into disabled wait state
245  */
246 
247 static inline void ATTRIB_NORET disabled_wait(unsigned long code)
248 {
249         unsigned long ctl_buf;
250         psw_t dw_psw;
251 
252         dw_psw.mask = PSW_BASE_BITS | PSW_MASK_WAIT;
253         dw_psw.addr = code;
254         /*
255          * Store status and then load disabled wait psw,
256          * the processor is dead afterwards
257          */
258 #ifndef __s390x__
259 	asm volatile(
260 		"	stctl	0,0,0(%2)\n"
261 		"	ni	0(%2),0xef\n"	/* switch off protection */
262 		"	lctl	0,0,0(%2)\n"
263 		"	stpt	0xd8\n"		/* store timer */
264 		"	stckc	0xe0\n"		/* store clock comparator */
265 		"	stpx	0x108\n"	/* store prefix register */
266 		"	stam	0,15,0x120\n"	/* store access registers */
267 		"	std	0,0x160\n"	/* store f0 */
268 		"	std	2,0x168\n"	/* store f2 */
269 		"	std	4,0x170\n"	/* store f4 */
270 		"	std	6,0x178\n"	/* store f6 */
271 		"	stm	0,15,0x180\n"	/* store general registers */
272 		"	stctl	0,15,0x1c0\n"	/* store control registers */
273 		"	oi	0x1c0,0x10\n"	/* fake protection bit */
274 		"	lpsw	0(%1)"
275 		: "=m" (ctl_buf)
276 		: "a" (&dw_psw), "a" (&ctl_buf), "m" (dw_psw) : "cc");
277 #else /* __s390x__ */
278 	asm volatile(
279 		"	stctg	0,0,0(%2)\n"
280 		"	ni	4(%2),0xef\n"	/* switch off protection */
281 		"	lctlg	0,0,0(%2)\n"
282 		"	lghi	1,0x1000\n"
283 		"	stpt	0x328(1)\n"	/* store timer */
284 		"	stckc	0x330(1)\n"	/* store clock comparator */
285 		"	stpx	0x318(1)\n"	/* store prefix register */
286 		"	stam	0,15,0x340(1)\n"/* store access registers */
287 		"	stfpc	0x31c(1)\n"	/* store fpu control */
288 		"	std	0,0x200(1)\n"	/* store f0 */
289 		"	std	1,0x208(1)\n"	/* store f1 */
290 		"	std	2,0x210(1)\n"	/* store f2 */
291 		"	std	3,0x218(1)\n"	/* store f3 */
292 		"	std	4,0x220(1)\n"	/* store f4 */
293 		"	std	5,0x228(1)\n"	/* store f5 */
294 		"	std	6,0x230(1)\n"	/* store f6 */
295 		"	std	7,0x238(1)\n"	/* store f7 */
296 		"	std	8,0x240(1)\n"	/* store f8 */
297 		"	std	9,0x248(1)\n"	/* store f9 */
298 		"	std	10,0x250(1)\n"	/* store f10 */
299 		"	std	11,0x258(1)\n"	/* store f11 */
300 		"	std	12,0x260(1)\n"	/* store f12 */
301 		"	std	13,0x268(1)\n"	/* store f13 */
302 		"	std	14,0x270(1)\n"	/* store f14 */
303 		"	std	15,0x278(1)\n"	/* store f15 */
304 		"	stmg	0,15,0x280(1)\n"/* store general registers */
305 		"	stctg	0,15,0x380(1)\n"/* store control registers */
306 		"	oi	0x384(1),0x10\n"/* fake protection bit */
307 		"	lpswe	0(%1)"
308 		: "=m" (ctl_buf)
309 		: "a" (&dw_psw), "a" (&ctl_buf), "m" (dw_psw) : "cc", "0");
310 #endif /* __s390x__ */
311 	while (1);
312 }
313 
314 /*
315  * Basic Machine Check/Program Check Handler.
316  */
317 
318 extern void s390_base_mcck_handler(void);
319 extern void s390_base_pgm_handler(void);
320 extern void s390_base_ext_handler(void);
321 
322 extern void (*s390_base_mcck_handler_fn)(void);
323 extern void (*s390_base_pgm_handler_fn)(void);
324 extern void (*s390_base_ext_handler_fn)(void);
325 
326 #define ARCH_LOW_ADDRESS_LIMIT	0x7fffffffUL
327 
328 #endif
329 
330 /*
331  * Helper macro for exception table entries
332  */
333 #ifndef __s390x__
334 #define EX_TABLE(_fault,_target)			\
335 	".section __ex_table,\"a\"\n"			\
336 	"	.align 4\n"				\
337 	"	.long  " #_fault "," #_target "\n"	\
338 	".previous\n"
339 #else
340 #define EX_TABLE(_fault,_target)			\
341 	".section __ex_table,\"a\"\n"			\
342 	"	.align 8\n"				\
343 	"	.quad  " #_fault "," #_target "\n"	\
344 	".previous\n"
345 #endif
346 
347 #endif                                 /* __ASM_S390_PROCESSOR_H           */
348