xref: /openbmc/linux/arch/s390/include/asm/processor.h (revision e8e0929d)
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/cpu.h>
18 #include <asm/page.h>
19 #include <asm/ptrace.h>
20 #include <asm/setup.h>
21 
22 #ifdef __KERNEL__
23 /*
24  * Default implementation of macro that returns current
25  * instruction pointer ("program counter").
26  */
27 #define current_text_addr() ({ void *pc; asm("basr %0,0" : "=a" (pc)); pc; })
28 
29 static inline void get_cpu_id(struct cpuid *ptr)
30 {
31 	asm volatile("stidp 0(%1)" : "=m" (*ptr) : "a" (ptr));
32 }
33 
34 extern void s390_adjust_jiffies(void);
35 extern void print_cpu_info(void);
36 extern int get_cpu_capability(unsigned int *);
37 
38 /*
39  * User space process size: 2GB for 31 bit, 4TB or 8PT for 64 bit.
40  */
41 #ifndef __s390x__
42 
43 #define TASK_SIZE		(1UL << 31)
44 #define TASK_UNMAPPED_BASE	(1UL << 30)
45 
46 #else /* __s390x__ */
47 
48 #define TASK_SIZE_OF(tsk)	((tsk)->mm->context.asce_limit)
49 #define TASK_UNMAPPED_BASE	(test_thread_flag(TIF_31BIT) ? \
50 					(1UL << 30) : (1UL << 41))
51 #define TASK_SIZE		TASK_SIZE_OF(current)
52 
53 #endif /* __s390x__ */
54 
55 #ifdef __KERNEL__
56 
57 #ifndef __s390x__
58 #define STACK_TOP		(1UL << 31)
59 #define STACK_TOP_MAX		(1UL << 31)
60 #else /* __s390x__ */
61 #define STACK_TOP		(1UL << (test_thread_flag(TIF_31BIT) ? 31:42))
62 #define STACK_TOP_MAX		(1UL << 42)
63 #endif /* __s390x__ */
64 
65 
66 #endif
67 
68 #define HAVE_ARCH_PICK_MMAP_LAYOUT
69 
70 typedef struct {
71         __u32 ar4;
72 } mm_segment_t;
73 
74 /*
75  * Thread structure
76  */
77 struct thread_struct {
78 	s390_fp_regs fp_regs;
79 	unsigned int  acrs[NUM_ACRS];
80         unsigned long ksp;              /* kernel stack pointer             */
81 	mm_segment_t mm_segment;
82         unsigned long prot_addr;        /* address of protection-excep.     */
83         unsigned int trap_no;
84         per_struct per_info;
85 	/* Used to give failing instruction back to user for ieee exceptions */
86 	unsigned long ieee_instruction_pointer;
87         /* pfault_wait is used to block the process on a pfault event */
88 	unsigned long pfault_wait;
89 };
90 
91 typedef struct thread_struct thread_struct;
92 
93 /*
94  * Stack layout of a C stack frame.
95  */
96 #ifndef __PACK_STACK
97 struct stack_frame {
98 	unsigned long back_chain;
99 	unsigned long empty1[5];
100 	unsigned long gprs[10];
101 	unsigned int  empty2[8];
102 };
103 #else
104 struct stack_frame {
105 	unsigned long empty1[5];
106 	unsigned int  empty2[8];
107 	unsigned long gprs[10];
108 	unsigned long back_chain;
109 };
110 #endif
111 
112 #define ARCH_MIN_TASKALIGN	8
113 
114 #define INIT_THREAD {							\
115 	.ksp = sizeof(init_stack) + (unsigned long) &init_stack,	\
116 }
117 
118 /*
119  * Do necessary setup to start up a new thread.
120  */
121 #define start_thread(regs, new_psw, new_stackp) do {		\
122 	set_fs(USER_DS);					\
123 	regs->psw.mask	= psw_user_bits;			\
124 	regs->psw.addr	= new_psw | PSW_ADDR_AMODE;		\
125 	regs->gprs[15]	= new_stackp;				\
126 } while (0)
127 
128 #define start_thread31(regs, new_psw, new_stackp) do {		\
129 	set_fs(USER_DS);					\
130 	regs->psw.mask	= psw_user32_bits;			\
131 	regs->psw.addr	= new_psw | PSW_ADDR_AMODE;		\
132 	regs->gprs[15]	= new_stackp;				\
133 	crst_table_downgrade(current->mm, 1UL << 31);		\
134 } while (0)
135 
136 /* Forward declaration, a strange C thing */
137 struct task_struct;
138 struct mm_struct;
139 struct seq_file;
140 
141 /* Free all resources held by a thread. */
142 extern void release_thread(struct task_struct *);
143 extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
144 
145 /* Prepare to copy thread state - unlazy all lazy status */
146 #define prepare_to_copy(tsk)	do { } while (0)
147 
148 /*
149  * Return saved PC of a blocked thread.
150  */
151 extern unsigned long thread_saved_pc(struct task_struct *t);
152 
153 /*
154  * Print register of task into buffer. Used in fs/proc/array.c.
155  */
156 extern void task_show_regs(struct seq_file *m, struct task_struct *task);
157 
158 extern void show_code(struct pt_regs *regs);
159 
160 unsigned long get_wchan(struct task_struct *p);
161 #define task_pt_regs(tsk) ((struct pt_regs *) \
162         (task_stack_page(tsk) + THREAD_SIZE) - 1)
163 #define KSTK_EIP(tsk)	(task_pt_regs(tsk)->psw.addr)
164 #define KSTK_ESP(tsk)	(task_pt_regs(tsk)->gprs[15])
165 
166 /*
167  * Give up the time slice of the virtual PU.
168  */
169 static inline void cpu_relax(void)
170 {
171 	if (MACHINE_HAS_DIAG44)
172 		asm volatile("diag 0,0,68");
173 	barrier();
174 }
175 
176 static inline void psw_set_key(unsigned int key)
177 {
178 	asm volatile("spka 0(%0)" : : "d" (key));
179 }
180 
181 /*
182  * Set PSW to specified value.
183  */
184 static inline void __load_psw(psw_t psw)
185 {
186 #ifndef __s390x__
187 	asm volatile("lpsw  0(%0)" : : "a" (&psw), "m" (psw) : "cc");
188 #else
189 	asm volatile("lpswe 0(%0)" : : "a" (&psw), "m" (psw) : "cc");
190 #endif
191 }
192 
193 /*
194  * Set PSW mask to specified value, while leaving the
195  * PSW addr pointing to the next instruction.
196  */
197 
198 static inline void __load_psw_mask (unsigned long mask)
199 {
200 	unsigned long addr;
201 	psw_t psw;
202 
203 	psw.mask = mask;
204 
205 #ifndef __s390x__
206 	asm volatile(
207 		"	basr	%0,0\n"
208 		"0:	ahi	%0,1f-0b\n"
209 		"	st	%0,4(%1)\n"
210 		"	lpsw	0(%1)\n"
211 		"1:"
212 		: "=&d" (addr) : "a" (&psw), "m" (psw) : "memory", "cc");
213 #else /* __s390x__ */
214 	asm volatile(
215 		"	larl	%0,1f\n"
216 		"	stg	%0,8(%1)\n"
217 		"	lpswe	0(%1)\n"
218 		"1:"
219 		: "=&d" (addr) : "a" (&psw), "m" (psw) : "memory", "cc");
220 #endif /* __s390x__ */
221 }
222 
223 /*
224  * Function to stop a processor until an interruption occurred
225  */
226 static inline void enabled_wait(void)
227 {
228 	__load_psw_mask(PSW_BASE_BITS | PSW_MASK_IO | PSW_MASK_EXT |
229 			PSW_MASK_MCHECK | PSW_MASK_WAIT | PSW_DEFAULT_KEY);
230 }
231 
232 /*
233  * Function to drop a processor into disabled wait state
234  */
235 
236 static inline void ATTRIB_NORET disabled_wait(unsigned long code)
237 {
238         unsigned long ctl_buf;
239         psw_t dw_psw;
240 
241         dw_psw.mask = PSW_BASE_BITS | PSW_MASK_WAIT;
242         dw_psw.addr = code;
243         /*
244          * Store status and then load disabled wait psw,
245          * the processor is dead afterwards
246          */
247 #ifndef __s390x__
248 	asm volatile(
249 		"	stctl	0,0,0(%2)\n"
250 		"	ni	0(%2),0xef\n"	/* switch off protection */
251 		"	lctl	0,0,0(%2)\n"
252 		"	stpt	0xd8\n"		/* store timer */
253 		"	stckc	0xe0\n"		/* store clock comparator */
254 		"	stpx	0x108\n"	/* store prefix register */
255 		"	stam	0,15,0x120\n"	/* store access registers */
256 		"	std	0,0x160\n"	/* store f0 */
257 		"	std	2,0x168\n"	/* store f2 */
258 		"	std	4,0x170\n"	/* store f4 */
259 		"	std	6,0x178\n"	/* store f6 */
260 		"	stm	0,15,0x180\n"	/* store general registers */
261 		"	stctl	0,15,0x1c0\n"	/* store control registers */
262 		"	oi	0x1c0,0x10\n"	/* fake protection bit */
263 		"	lpsw	0(%1)"
264 		: "=m" (ctl_buf)
265 		: "a" (&dw_psw), "a" (&ctl_buf), "m" (dw_psw) : "cc");
266 #else /* __s390x__ */
267 	asm volatile(
268 		"	stctg	0,0,0(%2)\n"
269 		"	ni	4(%2),0xef\n"	/* switch off protection */
270 		"	lctlg	0,0,0(%2)\n"
271 		"	lghi	1,0x1000\n"
272 		"	stpt	0x328(1)\n"	/* store timer */
273 		"	stckc	0x330(1)\n"	/* store clock comparator */
274 		"	stpx	0x318(1)\n"	/* store prefix register */
275 		"	stam	0,15,0x340(1)\n"/* store access registers */
276 		"	stfpc	0x31c(1)\n"	/* store fpu control */
277 		"	std	0,0x200(1)\n"	/* store f0 */
278 		"	std	1,0x208(1)\n"	/* store f1 */
279 		"	std	2,0x210(1)\n"	/* store f2 */
280 		"	std	3,0x218(1)\n"	/* store f3 */
281 		"	std	4,0x220(1)\n"	/* store f4 */
282 		"	std	5,0x228(1)\n"	/* store f5 */
283 		"	std	6,0x230(1)\n"	/* store f6 */
284 		"	std	7,0x238(1)\n"	/* store f7 */
285 		"	std	8,0x240(1)\n"	/* store f8 */
286 		"	std	9,0x248(1)\n"	/* store f9 */
287 		"	std	10,0x250(1)\n"	/* store f10 */
288 		"	std	11,0x258(1)\n"	/* store f11 */
289 		"	std	12,0x260(1)\n"	/* store f12 */
290 		"	std	13,0x268(1)\n"	/* store f13 */
291 		"	std	14,0x270(1)\n"	/* store f14 */
292 		"	std	15,0x278(1)\n"	/* store f15 */
293 		"	stmg	0,15,0x280(1)\n"/* store general registers */
294 		"	stctg	0,15,0x380(1)\n"/* store control registers */
295 		"	oi	0x384(1),0x10\n"/* fake protection bit */
296 		"	lpswe	0(%1)"
297 		: "=m" (ctl_buf)
298 		: "a" (&dw_psw), "a" (&ctl_buf), "m" (dw_psw) : "cc", "0", "1");
299 #endif /* __s390x__ */
300 	while (1);
301 }
302 
303 /*
304  * Basic Machine Check/Program Check Handler.
305  */
306 
307 extern void s390_base_mcck_handler(void);
308 extern void s390_base_pgm_handler(void);
309 extern void s390_base_ext_handler(void);
310 
311 extern void (*s390_base_mcck_handler_fn)(void);
312 extern void (*s390_base_pgm_handler_fn)(void);
313 extern void (*s390_base_ext_handler_fn)(void);
314 
315 #define ARCH_LOW_ADDRESS_LIMIT	0x7fffffffUL
316 
317 #endif
318 
319 /*
320  * Helper macro for exception table entries
321  */
322 #ifndef __s390x__
323 #define EX_TABLE(_fault,_target)			\
324 	".section __ex_table,\"a\"\n"			\
325 	"	.align 4\n"				\
326 	"	.long  " #_fault "," #_target "\n"	\
327 	".previous\n"
328 #else
329 #define EX_TABLE(_fault,_target)			\
330 	".section __ex_table,\"a\"\n"			\
331 	"	.align 8\n"				\
332 	"	.quad  " #_fault "," #_target "\n"	\
333 	".previous\n"
334 #endif
335 
336 #endif                                 /* __ASM_S390_PROCESSOR_H           */
337