diff options
Diffstat (limited to 'kernel/arch/s390/include/asm/facility.h')
-rw-r--r-- | kernel/arch/s390/include/asm/facility.h | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/kernel/arch/s390/include/asm/facility.h b/kernel/arch/s390/include/asm/facility.h new file mode 100644 index 000000000..0aa6a7ed9 --- /dev/null +++ b/kernel/arch/s390/include/asm/facility.h @@ -0,0 +1,67 @@ +/* + * Copyright IBM Corp. 1999, 2009 + * + * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com> + */ + +#ifndef __ASM_FACILITY_H +#define __ASM_FACILITY_H + +#include <linux/string.h> +#include <linux/preempt.h> +#include <asm/lowcore.h> + +#define MAX_FACILITY_BIT (256*8) /* stfle_fac_list has 256 bytes */ + +static inline int __test_facility(unsigned long nr, void *facilities) +{ + unsigned char *ptr; + + if (nr >= MAX_FACILITY_BIT) + return 0; + ptr = (unsigned char *) facilities + (nr >> 3); + return (*ptr & (0x80 >> (nr & 7))) != 0; +} + +/* + * The test_facility function uses the bit odering where the MSB is bit 0. + * That makes it easier to query facility bits with the bit number as + * documented in the Principles of Operation. + */ +static inline int test_facility(unsigned long nr) +{ + return __test_facility(nr, &S390_lowcore.stfle_fac_list); +} + +/** + * stfle - Store facility list extended + * @stfle_fac_list: array where facility list can be stored + * @size: size of passed in array in double words + */ +static inline void stfle(u64 *stfle_fac_list, int size) +{ + unsigned long nr; + + preempt_disable(); + asm volatile( + " .insn s,0xb2b10000,0(0)\n" /* stfl */ + "0:\n" + EX_TABLE(0b, 0b) + : "+m" (S390_lowcore.stfl_fac_list)); + nr = 4; /* bytes stored by stfl */ + memcpy(stfle_fac_list, &S390_lowcore.stfl_fac_list, 4); + if (S390_lowcore.stfl_fac_list & 0x01000000) { + /* More facility bits available with stfle */ + register unsigned long reg0 asm("0") = size - 1; + + asm volatile(".insn s,0xb2b00000,0(%1)" /* stfle */ + : "+d" (reg0) + : "a" (stfle_fac_list) + : "memory", "cc"); + nr = (reg0 + 1) * 8; /* # bytes stored by stfle */ + } + memset((char *) stfle_fac_list + nr, 0, size * 8 - nr); + preempt_enable(); +} + +#endif /* __ASM_FACILITY_H */ |