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[S390] Convert machine feature detection code to C.

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From: Heiko Carstens <heiko.carstens@de.ibm.com>
From: Carsten Otte <cotte@de.ibm.com>

This lets us use defines for the magic bits in machine flags instead
of using plain numbers all over the place.
In addition on newer machines features/facilities are indicated by the
result of the stfl instruction. So we use these bits instead of trying
to execute new instructions and check wether we get an exception or
not.
Also the mvpg instruction is always available when in zArch mode,
whereas the idte instruction is only available in zArch mode. This
results in some minor optimizations.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This commit is contained in:
Heiko Carstens
2008-04-30 13:38:45 +02:00
committed by Martin Schwidefsky
parent 8fc6365868
commit 2e5061e40a
7 changed files with 140 additions and 141 deletions
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109
arch/s390/kernel/early.c
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@ -139,15 +139,15 @@ static noinline __init void detect_machine_type(void)
/* Running under z/VM ? */
if (cpuinfo->cpu_id.version == 0xff)
machine_flags |= 1;
machine_flags |= MACHINE_FLAG_VM;
/* Running on a P/390 ? */
if (cpuinfo->cpu_id.machine == 0x7490)
machine_flags |= 4;
machine_flags |= MACHINE_FLAG_P390;
/* Running under KVM ? */
if (cpuinfo->cpu_id.version == 0xfe)
machine_flags |= 64;
machine_flags |= MACHINE_FLAG_KVM;
}
#ifdef CONFIG_64BIT
@ -268,6 +268,103 @@ static noinline __init void setup_lowcore_early(void)
s390_base_pgm_handler_fn = early_pgm_check_handler;
}
static __init void detect_mvpg(void)
{
#ifndef CONFIG_64BIT
int rc;
asm volatile(
" la 0,0\n"
" mvpg %2,%2\n"
"0: la %0,0\n"
"1:\n"
EX_TABLE(0b,1b)
: "=d" (rc) : "0" (-EOPNOTSUPP), "a" (0) : "memory", "cc", "0");
if (!rc)
machine_flags |= MACHINE_FLAG_MVPG;
#endif
}
static __init void detect_ieee(void)
{
#ifndef CONFIG_64BIT
int rc, tmp;
asm volatile(
" efpc %1,0\n"
"0: la %0,0\n"
"1:\n"
EX_TABLE(0b,1b)
: "=d" (rc), "=d" (tmp): "0" (-EOPNOTSUPP) : "cc");
if (!rc)
machine_flags |= MACHINE_FLAG_IEEE;
#endif
}
static __init void detect_csp(void)
{
#ifndef CONFIG_64BIT
int rc;
asm volatile(
" la 0,0\n"
" la 1,0\n"
" la 2,4\n"
" csp 0,2\n"
"0: la %0,0\n"
"1:\n"
EX_TABLE(0b,1b)
: "=d" (rc) : "0" (-EOPNOTSUPP) : "cc", "0", "1", "2");
if (!rc)
machine_flags |= MACHINE_FLAG_CSP;
#endif
}
static __init void detect_diag9c(void)
{
unsigned int cpu_address;
int rc;
cpu_address = stap();
asm volatile(
" diag %2,0,0x9c\n"
"0: la %0,0\n"
"1:\n"
EX_TABLE(0b,1b)
: "=d" (rc) : "0" (-EOPNOTSUPP), "d" (cpu_address) : "cc");
if (!rc)
machine_flags |= MACHINE_FLAG_DIAG9C;
}
static __init void detect_diag44(void)
{
#ifdef CONFIG_64BIT
int rc;
asm volatile(
" diag 0,0,0x44\n"
"0: la %0,0\n"
"1:\n"
EX_TABLE(0b,1b)
: "=d" (rc) : "0" (-EOPNOTSUPP) : "cc");
if (!rc)
machine_flags |= MACHINE_FLAG_DIAG44;
#endif
}
static __init void detect_machine_facilities(void)
{
#ifdef CONFIG_64BIT
unsigned int facilities;
facilities = stfl();
if (facilities & (1 << 28))
machine_flags |= MACHINE_FLAG_IDTE;
if (facilities & (1 << 4))
machine_flags |= MACHINE_FLAG_MVCOS;
#endif
}
/*
* Save ipl parameters, clear bss memory, initialize storage keys
* and create a kernel NSS at startup if the SAVESYS= parm is defined
@ -285,6 +382,12 @@ void __init startup_init(void)
create_kernel_nss();
sort_main_extable();
setup_lowcore_early();
detect_mvpg();
detect_ieee();
detect_csp();
detect_diag9c();
detect_diag44();
detect_machine_facilities();
sclp_read_info_early();
sclp_facilities_detect();
memsize = sclp_memory_detect();