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(((struct lowcore *)0)->stfle_fac_list) * 8)
17
__set_facility(unsigned long nr,void * facilities)18 static inline void __set_facility(unsigned long nr, void *facilities)
19 {
20 unsigned char *ptr = (unsigned char *) facilities;
21
22 if (nr >= MAX_FACILITY_BIT)
23 return;
24 ptr[nr >> 3] |= 0x80 >> (nr & 7);
25 }
26
__clear_facility(unsigned long nr,void * facilities)27 static inline void __clear_facility(unsigned long nr, void *facilities)
28 {
29 unsigned char *ptr = (unsigned char *) facilities;
30
31 if (nr >= MAX_FACILITY_BIT)
32 return;
33 ptr[nr >> 3] &= ~(0x80 >> (nr & 7));
34 }
35
__test_facility(unsigned long nr,void * facilities)36 static inline int __test_facility(unsigned long nr, void *facilities)
37 {
38 unsigned char *ptr;
39
40 if (nr >= MAX_FACILITY_BIT)
41 return 0;
42 ptr = (unsigned char *) facilities + (nr >> 3);
43 return (*ptr & (0x80 >> (nr & 7))) != 0;
44 }
45
46 /*
47 * The test_facility function uses the bit odering where the MSB is bit 0.
48 * That makes it easier to query facility bits with the bit number as
49 * documented in the Principles of Operation.
50 */
test_facility(unsigned long nr)51 static inline int test_facility(unsigned long nr)
52 {
53 unsigned long facilities_als[] = { FACILITIES_ALS };
54
55 if (__builtin_constant_p(nr) && nr < sizeof(facilities_als) * 8) {
56 if (__test_facility(nr, &facilities_als))
57 return 1;
58 }
59 return __test_facility(nr, &S390_lowcore.stfle_fac_list);
60 }
61
62 /**
63 * stfle - Store facility list extended
64 * @stfle_fac_list: array where facility list can be stored
65 * @size: size of passed in array in double words
66 */
stfle(u64 * stfle_fac_list,int size)67 static inline void stfle(u64 *stfle_fac_list, int size)
68 {
69 unsigned long nr;
70
71 preempt_disable();
72 asm volatile(
73 " stfl 0(0)\n"
74 : "=m" (S390_lowcore.stfl_fac_list));
75 nr = 4; /* bytes stored by stfl */
76 memcpy(stfle_fac_list, &S390_lowcore.stfl_fac_list, 4);
77 if (S390_lowcore.stfl_fac_list & 0x01000000) {
78 /* More facility bits available with stfle */
79 register unsigned long reg0 asm("0") = size - 1;
80
81 asm volatile(".insn s,0xb2b00000,0(%1)" /* stfle */
82 : "+d" (reg0)
83 : "a" (stfle_fac_list)
84 : "memory", "cc");
85 nr = (reg0 + 1) * 8; /* # bytes stored by stfle */
86 }
87 memset((char *) stfle_fac_list + nr, 0, size * 8 - nr);
88 preempt_enable();
89 }
90
91 #endif /* __ASM_FACILITY_H */
92
