xref: /openbmc/linux/arch/s390/include/asm/processor.h (revision baa7eb025ab14f3cba2e35c0a8648f9c9f01d24f)
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 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         /* pfault_wait is used to block the process on a pfault event */
86 	unsigned long pfault_wait;
87 };
88 
89 typedef struct thread_struct thread_struct;
90 
91 /*
92  * Stack layout of a C stack frame.
93  */
94 #ifndef __PACK_STACK
95 struct stack_frame {
96 	unsigned long back_chain;
97 	unsigned long empty1[5];
98 	unsigned long gprs[10];
99 	unsigned int  empty2[8];
100 };
101 #else
102 struct stack_frame {
103 	unsigned long empty1[5];
104 	unsigned int  empty2[8];
105 	unsigned long gprs[10];
106 	unsigned long back_chain;
107 };
108 #endif
109 
110 #define ARCH_MIN_TASKALIGN	8
111 
112 #define INIT_THREAD {							\
113 	.ksp = sizeof(init_stack) + (unsigned long) &init_stack,	\
114 }
115 
116 /*
117  * Do necessary setup to start up a new thread.
118  */
119 #define start_thread(regs, new_psw, new_stackp) do {		\
120 	set_fs(USER_DS);					\
121 	regs->psw.mask	= psw_user_bits;			\
122 	regs->psw.addr	= new_psw | PSW_ADDR_AMODE;		\
123 	regs->gprs[15]	= new_stackp;				\
124 } while (0)
125 
126 #define start_thread31(regs, new_psw, new_stackp) do {		\
127 	set_fs(USER_DS);					\
128 	regs->psw.mask	= psw_user32_bits;			\
129 	regs->psw.addr	= new_psw | PSW_ADDR_AMODE;		\
130 	regs->gprs[15]	= new_stackp;				\
131 	crst_table_downgrade(current->mm, 1UL << 31);		\
132 } while (0)
133 
134 /* Forward declaration, a strange C thing */
135 struct task_struct;
136 struct mm_struct;
137 struct seq_file;
138 
139 /* Free all resources held by a thread. */
140 extern void release_thread(struct task_struct *);
141 extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
142 
143 /* Prepare to copy thread state - unlazy all lazy status */
144 #define prepare_to_copy(tsk)	do { } while (0)
145 
146 /*
147  * Return saved PC of a blocked thread.
148  */
149 extern unsigned long thread_saved_pc(struct task_struct *t);
150 
151 /*
152  * Print register of task into buffer. Used in fs/proc/array.c.
153  */
154 extern void task_show_regs(struct seq_file *m, struct task_struct *task);
155 
156 extern void show_code(struct pt_regs *regs);
157 
158 unsigned long get_wchan(struct task_struct *p);
159 #define task_pt_regs(tsk) ((struct pt_regs *) \
160         (task_stack_page(tsk) + THREAD_SIZE) - 1)
161 #define KSTK_EIP(tsk)	(task_pt_regs(tsk)->psw.addr)
162 #define KSTK_ESP(tsk)	(task_pt_regs(tsk)->gprs[15])
163 
164 /*
165  * Give up the time slice of the virtual PU.
166  */
167 static inline void cpu_relax(void)
168 {
169 	if (MACHINE_HAS_DIAG44)
170 		asm volatile("diag 0,0,68");
171 	barrier();
172 }
173 
174 static inline void psw_set_key(unsigned int key)
175 {
176 	asm volatile("spka 0(%0)" : : "d" (key));
177 }
178 
179 /*
180  * Set PSW to specified value.
181  */
182 static inline void __load_psw(psw_t psw)
183 {
184 #ifndef __s390x__
185 	asm volatile("lpsw  %0" : : "Q" (psw) : "cc");
186 #else
187 	asm volatile("lpswe %0" : : "Q" (psw) : "cc");
188 #endif
189 }
190 
191 /*
192  * Set PSW mask to specified value, while leaving the
193  * PSW addr pointing to the next instruction.
194  */
195 
196 static inline void __load_psw_mask (unsigned long mask)
197 {
198 	unsigned long addr;
199 	psw_t psw;
200 
201 	psw.mask = mask;
202 
203 #ifndef __s390x__
204 	asm volatile(
205 		"	basr	%0,0\n"
206 		"0:	ahi	%0,1f-0b\n"
207 		"	st	%0,%O1+4(%R1)\n"
208 		"	lpsw	%1\n"
209 		"1:"
210 		: "=&d" (addr), "=Q" (psw) : "Q" (psw) : "memory", "cc");
211 #else /* __s390x__ */
212 	asm volatile(
213 		"	larl	%0,1f\n"
214 		"	stg	%0,%O1+8(%R1)\n"
215 		"	lpswe	%1\n"
216 		"1:"
217 		: "=&d" (addr), "=Q" (psw) : "Q" (psw) : "memory", "cc");
218 #endif /* __s390x__ */
219 }
220 
221 /*
222  * Function to stop a processor until an interruption occurred
223  */
224 static inline void enabled_wait(void)
225 {
226 	__load_psw_mask(PSW_BASE_BITS | PSW_MASK_IO | PSW_MASK_EXT |
227 			PSW_MASK_MCHECK | PSW_MASK_WAIT | PSW_DEFAULT_KEY);
228 }
229 
230 /*
231  * Function to drop a processor into disabled wait state
232  */
233 
234 static inline void ATTRIB_NORET disabled_wait(unsigned long code)
235 {
236         unsigned long ctl_buf;
237         psw_t dw_psw;
238 
239         dw_psw.mask = PSW_BASE_BITS | PSW_MASK_WAIT;
240         dw_psw.addr = code;
241         /*
242          * Store status and then load disabled wait psw,
243          * the processor is dead afterwards
244          */
245 #ifndef __s390x__
246 	asm volatile(
247 		"	stctl	0,0,0(%2)\n"
248 		"	ni	0(%2),0xef\n"	/* switch off protection */
249 		"	lctl	0,0,0(%2)\n"
250 		"	stpt	0xd8\n"		/* store timer */
251 		"	stckc	0xe0\n"		/* store clock comparator */
252 		"	stpx	0x108\n"	/* store prefix register */
253 		"	stam	0,15,0x120\n"	/* store access registers */
254 		"	std	0,0x160\n"	/* store f0 */
255 		"	std	2,0x168\n"	/* store f2 */
256 		"	std	4,0x170\n"	/* store f4 */
257 		"	std	6,0x178\n"	/* store f6 */
258 		"	stm	0,15,0x180\n"	/* store general registers */
259 		"	stctl	0,15,0x1c0\n"	/* store control registers */
260 		"	oi	0x1c0,0x10\n"	/* fake protection bit */
261 		"	lpsw	0(%1)"
262 		: "=m" (ctl_buf)
263 		: "a" (&dw_psw), "a" (&ctl_buf), "m" (dw_psw) : "cc");
264 #else /* __s390x__ */
265 	asm volatile(
266 		"	stctg	0,0,0(%2)\n"
267 		"	ni	4(%2),0xef\n"	/* switch off protection */
268 		"	lctlg	0,0,0(%2)\n"
269 		"	lghi	1,0x1000\n"
270 		"	stpt	0x328(1)\n"	/* store timer */
271 		"	stckc	0x330(1)\n"	/* store clock comparator */
272 		"	stpx	0x318(1)\n"	/* store prefix register */
273 		"	stam	0,15,0x340(1)\n"/* store access registers */
274 		"	stfpc	0x31c(1)\n"	/* store fpu control */
275 		"	std	0,0x200(1)\n"	/* store f0 */
276 		"	std	1,0x208(1)\n"	/* store f1 */
277 		"	std	2,0x210(1)\n"	/* store f2 */
278 		"	std	3,0x218(1)\n"	/* store f3 */
279 		"	std	4,0x220(1)\n"	/* store f4 */
280 		"	std	5,0x228(1)\n"	/* store f5 */
281 		"	std	6,0x230(1)\n"	/* store f6 */
282 		"	std	7,0x238(1)\n"	/* store f7 */
283 		"	std	8,0x240(1)\n"	/* store f8 */
284 		"	std	9,0x248(1)\n"	/* store f9 */
285 		"	std	10,0x250(1)\n"	/* store f10 */
286 		"	std	11,0x258(1)\n"	/* store f11 */
287 		"	std	12,0x260(1)\n"	/* store f12 */
288 		"	std	13,0x268(1)\n"	/* store f13 */
289 		"	std	14,0x270(1)\n"	/* store f14 */
290 		"	std	15,0x278(1)\n"	/* store f15 */
291 		"	stmg	0,15,0x280(1)\n"/* store general registers */
292 		"	stctg	0,15,0x380(1)\n"/* store control registers */
293 		"	oi	0x384(1),0x10\n"/* fake protection bit */
294 		"	lpswe	0(%1)"
295 		: "=m" (ctl_buf)
296 		: "a" (&dw_psw), "a" (&ctl_buf), "m" (dw_psw) : "cc", "0", "1");
297 #endif /* __s390x__ */
298 	while (1);
299 }
300 
301 /*
302  * Basic Machine Check/Program Check Handler.
303  */
304 
305 extern void s390_base_mcck_handler(void);
306 extern void s390_base_pgm_handler(void);
307 extern void s390_base_ext_handler(void);
308 
309 extern void (*s390_base_mcck_handler_fn)(void);
310 extern void (*s390_base_pgm_handler_fn)(void);
311 extern void (*s390_base_ext_handler_fn)(void);
312 
313 #define ARCH_LOW_ADDRESS_LIMIT	0x7fffffffUL
314 
315 #endif
316 
317 /*
318  * Helper macro for exception table entries
319  */
320 #ifndef __s390x__
321 #define EX_TABLE(_fault,_target)			\
322 	".section __ex_table,\"a\"\n"			\
323 	"	.align 4\n"				\
324 	"	.long  " #_fault "," #_target "\n"	\
325 	".previous\n"
326 #else
327 #define EX_TABLE(_fault,_target)			\
328 	".section __ex_table,\"a\"\n"			\
329 	"	.align 8\n"				\
330 	"	.quad  " #_fault "," #_target "\n"	\
331 	".previous\n"
332 #endif
333 
334 #endif                                 /* __ASM_S390_PROCESSOR_H           */
335