xref: /openbmc/linux/arch/s390/include/asm/facility.h (revision 0661cb2a)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Copyright IBM Corp. 1999, 2009
4  *
5  * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
6  */
7 
8 #ifndef __ASM_FACILITY_H
9 #define __ASM_FACILITY_H
10 
11 #include <asm/facility-defs.h>
12 #include <linux/string.h>
13 #include <linux/preempt.h>
14 #include <asm/lowcore.h>
15 
16 #define MAX_FACILITY_BIT (sizeof(stfle_fac_list) * 8)
17 
18 extern u64 stfle_fac_list[16];
19 extern u64 alt_stfle_fac_list[16];
20 
21 static inline void __set_facility(unsigned long nr, void *facilities)
22 {
23 	unsigned char *ptr = (unsigned char *) facilities;
24 
25 	if (nr >= MAX_FACILITY_BIT)
26 		return;
27 	ptr[nr >> 3] |= 0x80 >> (nr & 7);
28 }
29 
30 static inline void __clear_facility(unsigned long nr, void *facilities)
31 {
32 	unsigned char *ptr = (unsigned char *) facilities;
33 
34 	if (nr >= MAX_FACILITY_BIT)
35 		return;
36 	ptr[nr >> 3] &= ~(0x80 >> (nr & 7));
37 }
38 
39 static inline int __test_facility(unsigned long nr, void *facilities)
40 {
41 	unsigned char *ptr;
42 
43 	if (nr >= MAX_FACILITY_BIT)
44 		return 0;
45 	ptr = (unsigned char *) facilities + (nr >> 3);
46 	return (*ptr & (0x80 >> (nr & 7))) != 0;
47 }
48 
49 /*
50  * The test_facility function uses the bit ordering where the MSB is bit 0.
51  * That makes it easier to query facility bits with the bit number as
52  * documented in the Principles of Operation.
53  */
54 static inline int test_facility(unsigned long nr)
55 {
56 	unsigned long facilities_als[] = { FACILITIES_ALS };
57 
58 	if (__builtin_constant_p(nr) && nr < sizeof(facilities_als) * 8) {
59 		if (__test_facility(nr, &facilities_als))
60 			return 1;
61 	}
62 	return __test_facility(nr, &stfle_fac_list);
63 }
64 
65 static inline unsigned long __stfle_asm(u64 *stfle_fac_list, int size)
66 {
67 	unsigned long reg0 = size - 1;
68 
69 	asm volatile(
70 		"	lgr	0,%[reg0]\n"
71 		"	.insn	s,0xb2b00000,%[list]\n" /* stfle */
72 		"	lgr	%[reg0],0\n"
73 		: [reg0] "+&d" (reg0), [list] "+Q" (*stfle_fac_list)
74 		:
75 		: "memory", "cc", "0");
76 	return reg0;
77 }
78 
79 /**
80  * stfle - Store facility list extended
81  * @stfle_fac_list: array where facility list can be stored
82  * @size: size of passed in array in double words
83  */
84 static inline void __stfle(u64 *stfle_fac_list, int size)
85 {
86 	unsigned long nr;
87 	u32 stfl_fac_list;
88 
89 	asm volatile(
90 		"	stfl	0(0)\n"
91 		: "=m" (S390_lowcore.stfl_fac_list));
92 	stfl_fac_list = S390_lowcore.stfl_fac_list;
93 	memcpy(stfle_fac_list, &stfl_fac_list, 4);
94 	nr = 4; /* bytes stored by stfl */
95 	if (stfl_fac_list & 0x01000000) {
96 		/* More facility bits available with stfle */
97 		nr = __stfle_asm(stfle_fac_list, size);
98 		nr = min_t(unsigned long, (nr + 1) * 8, size * 8);
99 	}
100 	memset((char *) stfle_fac_list + nr, 0, size * 8 - nr);
101 }
102 
103 static inline void stfle(u64 *stfle_fac_list, int size)
104 {
105 	preempt_disable();
106 	__stfle(stfle_fac_list, size);
107 	preempt_enable();
108 }
109 
110 #endif /* __ASM_FACILITY_H */
111