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 12 #ifndef __ASSEMBLY__ 13 14 #include <linux/string.h> 15 #include <linux/preempt.h> 16 #include <asm/lowcore.h> 17 18 #define MAX_FACILITY_BIT (256*8) /* stfle_fac_list has 256 bytes */ 19 20 static inline int __test_facility(unsigned long nr, void *facilities) 21 { 22 unsigned char *ptr; 23 24 if (nr >= MAX_FACILITY_BIT) 25 return 0; 26 ptr = (unsigned char *) facilities + (nr >> 3); 27 return (*ptr & (0x80 >> (nr & 7))) != 0; 28 } 29 30 /* 31 * The test_facility function uses the bit odering where the MSB is bit 0. 32 * That makes it easier to query facility bits with the bit number as 33 * documented in the Principles of Operation. 34 */ 35 static inline int test_facility(unsigned long nr) 36 { 37 unsigned long facilities_als[] = { FACILITIES_ALS }; 38 39 if (__builtin_constant_p(nr) && nr < sizeof(facilities_als) * 8) { 40 if (__test_facility(nr, &facilities_als)) 41 return 1; 42 } 43 return __test_facility(nr, &S390_lowcore.stfle_fac_list); 44 } 45 46 /** 47 * stfle - Store facility list extended 48 * @stfle_fac_list: array where facility list can be stored 49 * @size: size of passed in array in double words 50 */ 51 static inline void stfle(u64 *stfle_fac_list, int size) 52 { 53 unsigned long nr; 54 55 preempt_disable(); 56 asm volatile( 57 " stfl 0(0)\n" 58 : "=m" (S390_lowcore.stfl_fac_list)); 59 nr = 4; /* bytes stored by stfl */ 60 memcpy(stfle_fac_list, &S390_lowcore.stfl_fac_list, 4); 61 if (S390_lowcore.stfl_fac_list & 0x01000000) { 62 /* More facility bits available with stfle */ 63 register unsigned long reg0 asm("0") = size - 1; 64 65 asm volatile(".insn s,0xb2b00000,0(%1)" /* stfle */ 66 : "+d" (reg0) 67 : "a" (stfle_fac_list) 68 : "memory", "cc"); 69 nr = (reg0 + 1) * 8; /* # bytes stored by stfle */ 70 } 71 memset((char *) stfle_fac_list + nr, 0, size * 8 - nr); 72 preempt_enable(); 73 } 74 75 #endif /* __ASSEMBLY__ */ 76 #endif /* __ASM_FACILITY_H */ 77