1 /* 2 * Copyright IBM Corp. 1999, 2009 3 * 4 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com> 5 */ 6 7 #ifndef __ASM_FACILITY_H 8 #define __ASM_FACILITY_H 9 10 #include <generated/facilities.h> 11 #include <linux/string.h> 12 #include <linux/preempt.h> 13 #include <asm/lowcore.h> 14 15 #define MAX_FACILITY_BIT (sizeof(((struct lowcore *)0)->stfle_fac_list) * 8) 16 17 static inline int __test_facility(unsigned long nr, void *facilities) 18 { 19 unsigned char *ptr; 20 21 if (nr >= MAX_FACILITY_BIT) 22 return 0; 23 ptr = (unsigned char *) facilities + (nr >> 3); 24 return (*ptr & (0x80 >> (nr & 7))) != 0; 25 } 26 27 /* 28 * The test_facility function uses the bit odering where the MSB is bit 0. 29 * That makes it easier to query facility bits with the bit number as 30 * documented in the Principles of Operation. 31 */ 32 static inline int test_facility(unsigned long nr) 33 { 34 unsigned long facilities_als[] = { FACILITIES_ALS }; 35 36 if (__builtin_constant_p(nr) && nr < sizeof(facilities_als) * 8) { 37 if (__test_facility(nr, &facilities_als)) 38 return 1; 39 } 40 return __test_facility(nr, &S390_lowcore.stfle_fac_list); 41 } 42 43 /** 44 * stfle - Store facility list extended 45 * @stfle_fac_list: array where facility list can be stored 46 * @size: size of passed in array in double words 47 */ 48 static inline void stfle(u64 *stfle_fac_list, int size) 49 { 50 unsigned long nr; 51 52 preempt_disable(); 53 asm volatile( 54 " stfl 0(0)\n" 55 : "=m" (S390_lowcore.stfl_fac_list)); 56 nr = 4; /* bytes stored by stfl */ 57 memcpy(stfle_fac_list, &S390_lowcore.stfl_fac_list, 4); 58 if (S390_lowcore.stfl_fac_list & 0x01000000) { 59 /* More facility bits available with stfle */ 60 register unsigned long reg0 asm("0") = size - 1; 61 62 asm volatile(".insn s,0xb2b00000,0(%1)" /* stfle */ 63 : "+d" (reg0) 64 : "a" (stfle_fac_list) 65 : "memory", "cc"); 66 nr = (reg0 + 1) * 8; /* # bytes stored by stfle */ 67 } 68 memset((char *) stfle_fac_list + nr, 0, size * 8 - nr); 69 preempt_enable(); 70 } 71 72 #endif /* __ASM_FACILITY_H */ 73