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 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 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 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 */ 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 static inline unsigned long __stfle_asm(u64 *stfle_fac_list, int size) 63 { 64 register unsigned long reg0 asm("0") = size - 1; 65 66 asm volatile( 67 ".insn s,0xb2b00000,0(%1)" /* stfle */ 68 : "+d" (reg0) 69 : "a" (stfle_fac_list) 70 : "memory", "cc"); 71 return reg0; 72 } 73 74 /** 75 * stfle - Store facility list extended 76 * @stfle_fac_list: array where facility list can be stored 77 * @size: size of passed in array in double words 78 */ 79 static inline void __stfle(u64 *stfle_fac_list, int size) 80 { 81 unsigned long nr; 82 83 asm volatile( 84 " stfl 0(0)\n" 85 : "=m" (S390_lowcore.stfl_fac_list)); 86 nr = 4; /* bytes stored by stfl */ 87 memcpy(stfle_fac_list, &S390_lowcore.stfl_fac_list, 4); 88 if (S390_lowcore.stfl_fac_list & 0x01000000) { 89 /* More facility bits available with stfle */ 90 nr = __stfle_asm(stfle_fac_list, size); 91 nr = min_t(unsigned long, (nr + 1) * 8, size * 8); 92 } 93 memset((char *) stfle_fac_list + nr, 0, size * 8 - nr); 94 } 95 96 static inline void stfle(u64 *stfle_fac_list, int size) 97 { 98 preempt_disable(); 99 __stfle(stfle_fac_list, size); 100 preempt_enable(); 101 } 102 103 #endif /* __ASM_FACILITY_H */ 104