[S390] cleanup facility list handling
Store the facility list once at system startup with stfl/stfle and
reuse the result for all facility tests.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/kernel/early.c b/arch/s390/kernel/early.c
index 0badc63..d2455d4 100644
--- a/arch/s390/kernel/early.c
+++ b/arch/s390/kernel/early.c
@@ -256,13 +256,35 @@
s390_base_pgm_handler_fn = early_pgm_check_handler;
}
+static noinline __init void setup_facility_list(void)
+{
+ unsigned long nr;
+
+ S390_lowcore.stfl_fac_list = 0;
+ asm volatile(
+ " .insn s,0xb2b10000,0(0)\n" /* stfl */
+ "0:\n"
+ EX_TABLE(0b,0b) : "=m" (S390_lowcore.stfl_fac_list));
+ memcpy(&S390_lowcore.stfle_fac_list, &S390_lowcore.stfl_fac_list, 4);
+ nr = 4; /* # bytes stored by stfl */
+ if (test_facility(7)) {
+ /* More facility bits available with stfle */
+ register unsigned long reg0 asm("0") = MAX_FACILITY_BIT/64 - 1;
+ asm volatile(".insn s,0xb2b00000,%0" /* stfle */
+ : "=m" (S390_lowcore.stfle_fac_list), "+d" (reg0)
+ : : "cc");
+ nr = (reg0 + 1) * 8; /* # bytes stored by stfle */
+ }
+ memset((char *) S390_lowcore.stfle_fac_list + nr, 0,
+ MAX_FACILITY_BIT/8 - nr);
+}
+
static noinline __init void setup_hpage(void)
{
#ifndef CONFIG_DEBUG_PAGEALLOC
unsigned int facilities;
- facilities = stfl();
- if (!(facilities & (1UL << 23)) || !(facilities & (1UL << 29)))
+ if (!test_facility(2) || !test_facility(8))
return;
S390_lowcore.machine_flags |= MACHINE_FLAG_HPAGE;
__ctl_set_bit(0, 23);
@@ -356,18 +378,13 @@
static __init void detect_machine_facilities(void)
{
#ifdef CONFIG_64BIT
- unsigned int facilities;
- unsigned long long facility_bits;
-
- facilities = stfl();
- if (facilities & (1 << 28))
+ if (test_facility(3))
S390_lowcore.machine_flags |= MACHINE_FLAG_IDTE;
- if (facilities & (1 << 23))
+ if (test_facility(8))
S390_lowcore.machine_flags |= MACHINE_FLAG_PFMF;
- if (facilities & (1 << 4))
+ if (test_facility(27))
S390_lowcore.machine_flags |= MACHINE_FLAG_MVCOS;
- if ((stfle(&facility_bits, 1) > 0) &&
- (facility_bits & (1ULL << (63 - 40))))
+ if (test_facility(40))
S390_lowcore.machine_flags |= MACHINE_FLAG_SPP;
#endif
}
@@ -448,6 +465,7 @@
lockdep_off();
sort_main_extable();
setup_lowcore_early();
+ setup_facility_list();
detect_machine_type();
ipl_update_parameters();
setup_boot_command_line();