xref: /openbmc/linux/arch/s390/include/asm/processor.h (revision 81d67439)
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" : "=Q" (*ptr));
32 }
33 
34 extern void s390_adjust_jiffies(void);
35 extern int get_cpu_capability(unsigned int *);
36 
37 /*
38  * User space process size: 2GB for 31 bit, 4TB or 8PT for 64 bit.
39  */
40 #ifndef __s390x__
41 
42 #define TASK_SIZE		(1UL << 31)
43 #define TASK_UNMAPPED_BASE	(1UL << 30)
44 
45 #else /* __s390x__ */
46 
47 #define TASK_SIZE_OF(tsk)	((tsk)->mm->context.asce_limit)
48 #define TASK_UNMAPPED_BASE	(test_thread_flag(TIF_31BIT) ? \
49 					(1UL << 30) : (1UL << 41))
50 #define TASK_SIZE		TASK_SIZE_OF(current)
51 
52 #endif /* __s390x__ */
53 
54 #ifdef __KERNEL__
55 
56 #ifndef __s390x__
57 #define STACK_TOP		(1UL << 31)
58 #define STACK_TOP_MAX		(1UL << 31)
59 #else /* __s390x__ */
60 #define STACK_TOP		(1UL << (test_thread_flag(TIF_31BIT) ? 31:42))
61 #define STACK_TOP_MAX		(1UL << 42)
62 #endif /* __s390x__ */
63 
64 
65 #endif
66 
67 #define HAVE_ARCH_PICK_MMAP_LAYOUT
68 
69 typedef struct {
70         __u32 ar4;
71 } mm_segment_t;
72 
73 /*
74  * Thread structure
75  */
76 struct thread_struct {
77 	s390_fp_regs fp_regs;
78 	unsigned int  acrs[NUM_ACRS];
79         unsigned long ksp;              /* kernel stack pointer             */
80 	mm_segment_t mm_segment;
81         unsigned long prot_addr;        /* address of protection-excep.     */
82         unsigned int trap_no;
83 	unsigned long gmap_addr;	/* address of last gmap fault. */
84 	struct per_regs per_user;	/* User specified PER registers */
85 	struct per_event per_event;	/* Cause of the last PER trap */
86         /* pfault_wait is used to block the process on a pfault event */
87 	unsigned long pfault_wait;
88 	struct list_head list;
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 extern void show_code(struct pt_regs *regs);
154 
155 unsigned long get_wchan(struct task_struct *p);
156 #define task_pt_regs(tsk) ((struct pt_regs *) \
157         (task_stack_page(tsk) + THREAD_SIZE) - 1)
158 #define KSTK_EIP(tsk)	(task_pt_regs(tsk)->psw.addr)
159 #define KSTK_ESP(tsk)	(task_pt_regs(tsk)->gprs[15])
160 
161 /*
162  * Give up the time slice of the virtual PU.
163  */
164 static inline void cpu_relax(void)
165 {
166 	if (MACHINE_HAS_DIAG44)
167 		asm volatile("diag 0,0,68");
168 	barrier();
169 }
170 
171 static inline void psw_set_key(unsigned int key)
172 {
173 	asm volatile("spka 0(%0)" : : "d" (key));
174 }
175 
176 /*
177  * Set PSW to specified value.
178  */
179 static inline void __load_psw(psw_t psw)
180 {
181 #ifndef __s390x__
182 	asm volatile("lpsw  %0" : : "Q" (psw) : "cc");
183 #else
184 	asm volatile("lpswe %0" : : "Q" (psw) : "cc");
185 #endif
186 }
187 
188 /*
189  * Set PSW mask to specified value, while leaving the
190  * PSW addr pointing to the next instruction.
191  */
192 
193 static inline void __load_psw_mask (unsigned long mask)
194 {
195 	unsigned long addr;
196 	psw_t psw;
197 
198 	psw.mask = mask;
199 
200 #ifndef __s390x__
201 	asm volatile(
202 		"	basr	%0,0\n"
203 		"0:	ahi	%0,1f-0b\n"
204 		"	st	%0,%O1+4(%R1)\n"
205 		"	lpsw	%1\n"
206 		"1:"
207 		: "=&d" (addr), "=Q" (psw) : "Q" (psw) : "memory", "cc");
208 #else /* __s390x__ */
209 	asm volatile(
210 		"	larl	%0,1f\n"
211 		"	stg	%0,%O1+8(%R1)\n"
212 		"	lpswe	%1\n"
213 		"1:"
214 		: "=&d" (addr), "=Q" (psw) : "Q" (psw) : "memory", "cc");
215 #endif /* __s390x__ */
216 }
217 
218 /*
219  * Function to stop a processor until an interruption occurred
220  */
221 static inline void enabled_wait(void)
222 {
223 	__load_psw_mask(PSW_BASE_BITS | PSW_MASK_IO | PSW_MASK_EXT |
224 			PSW_MASK_MCHECK | PSW_MASK_WAIT | PSW_DEFAULT_KEY);
225 }
226 
227 /*
228  * Function to drop a processor into disabled wait state
229  */
230 
231 static inline void ATTRIB_NORET disabled_wait(unsigned long code)
232 {
233         unsigned long ctl_buf;
234         psw_t dw_psw;
235 
236         dw_psw.mask = PSW_BASE_BITS | PSW_MASK_WAIT;
237         dw_psw.addr = code;
238         /*
239          * Store status and then load disabled wait psw,
240          * the processor is dead afterwards
241          */
242 #ifndef __s390x__
243 	asm volatile(
244 		"	stctl	0,0,0(%2)\n"
245 		"	ni	0(%2),0xef\n"	/* switch off protection */
246 		"	lctl	0,0,0(%2)\n"
247 		"	stpt	0xd8\n"		/* store timer */
248 		"	stckc	0xe0\n"		/* store clock comparator */
249 		"	stpx	0x108\n"	/* store prefix register */
250 		"	stam	0,15,0x120\n"	/* store access registers */
251 		"	std	0,0x160\n"	/* store f0 */
252 		"	std	2,0x168\n"	/* store f2 */
253 		"	std	4,0x170\n"	/* store f4 */
254 		"	std	6,0x178\n"	/* store f6 */
255 		"	stm	0,15,0x180\n"	/* store general registers */
256 		"	stctl	0,15,0x1c0\n"	/* store control registers */
257 		"	oi	0x1c0,0x10\n"	/* fake protection bit */
258 		"	lpsw	0(%1)"
259 		: "=m" (ctl_buf)
260 		: "a" (&dw_psw), "a" (&ctl_buf), "m" (dw_psw) : "cc");
261 #else /* __s390x__ */
262 	asm volatile(
263 		"	stctg	0,0,0(%2)\n"
264 		"	ni	4(%2),0xef\n"	/* switch off protection */
265 		"	lctlg	0,0,0(%2)\n"
266 		"	lghi	1,0x1000\n"
267 		"	stpt	0x328(1)\n"	/* store timer */
268 		"	stckc	0x330(1)\n"	/* store clock comparator */
269 		"	stpx	0x318(1)\n"	/* store prefix register */
270 		"	stam	0,15,0x340(1)\n"/* store access registers */
271 		"	stfpc	0x31c(1)\n"	/* store fpu control */
272 		"	std	0,0x200(1)\n"	/* store f0 */
273 		"	std	1,0x208(1)\n"	/* store f1 */
274 		"	std	2,0x210(1)\n"	/* store f2 */
275 		"	std	3,0x218(1)\n"	/* store f3 */
276 		"	std	4,0x220(1)\n"	/* store f4 */
277 		"	std	5,0x228(1)\n"	/* store f5 */
278 		"	std	6,0x230(1)\n"	/* store f6 */
279 		"	std	7,0x238(1)\n"	/* store f7 */
280 		"	std	8,0x240(1)\n"	/* store f8 */
281 		"	std	9,0x248(1)\n"	/* store f9 */
282 		"	std	10,0x250(1)\n"	/* store f10 */
283 		"	std	11,0x258(1)\n"	/* store f11 */
284 		"	std	12,0x260(1)\n"	/* store f12 */
285 		"	std	13,0x268(1)\n"	/* store f13 */
286 		"	std	14,0x270(1)\n"	/* store f14 */
287 		"	std	15,0x278(1)\n"	/* store f15 */
288 		"	stmg	0,15,0x280(1)\n"/* store general registers */
289 		"	stctg	0,15,0x380(1)\n"/* store control registers */
290 		"	oi	0x384(1),0x10\n"/* fake protection bit */
291 		"	lpswe	0(%1)"
292 		: "=m" (ctl_buf)
293 		: "a" (&dw_psw), "a" (&ctl_buf), "m" (dw_psw) : "cc", "0", "1");
294 #endif /* __s390x__ */
295 	while (1);
296 }
297 
298 /*
299  * Basic Machine Check/Program Check Handler.
300  */
301 
302 extern void s390_base_mcck_handler(void);
303 extern void s390_base_pgm_handler(void);
304 extern void s390_base_ext_handler(void);
305 
306 extern void (*s390_base_mcck_handler_fn)(void);
307 extern void (*s390_base_pgm_handler_fn)(void);
308 extern void (*s390_base_ext_handler_fn)(void);
309 
310 #define ARCH_LOW_ADDRESS_LIMIT	0x7fffffffUL
311 
312 #endif
313 
314 /*
315  * Helper macro for exception table entries
316  */
317 #ifndef __s390x__
318 #define EX_TABLE(_fault,_target)			\
319 	".section __ex_table,\"a\"\n"			\
320 	"	.align 4\n"				\
321 	"	.long  " #_fault "," #_target "\n"	\
322 	".previous\n"
323 #else
324 #define EX_TABLE(_fault,_target)			\
325 	".section __ex_table,\"a\"\n"			\
326 	"	.align 8\n"				\
327 	"	.quad  " #_fault "," #_target "\n"	\
328 	".previous\n"
329 #endif
330 
331 #endif                                 /* __ASM_S390_PROCESSOR_H           */
332