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powerpc: Expose PMCs & cache topology in sysfs on 32-bit 

The file arch/powerpc/kernel/sysfs.c is currently only compiled for
64-bit kernels.  It contain code to register CPU sysdevs in sysfs and
add various properties such as cache topology and raw access by root
to performance monitor counters (PMCs).  A lot of that can be re-used
as is on 32-bits.

This makes the file be built for both, with appropriate ifdef'ing
for the few bits that are really 64-bit specific, and adds some
support for the raw PMCs for 75x and 74xx processors.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
hifive-unleashed-5.1
Benjamin Herrenschmidt 2008-08-18 14:23:51 +10:00 committed by Paul Mackerras
parent 41eba0ad00
commit b950bdd0fc
6 changed files with 117 additions and 33 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
arch/powerpc/include/asm/cputable.h
View File

@ -62,6 +62,7 @@ enum powerpc_pmc_type {
PPC_PMC_DEFAULT = 0,
PPC_PMC_IBM = 1,
PPC_PMC_PA6T = 2,
PPC_PMC_G4 = 3,
};
struct pt_regs;

4
arch/powerpc/kernel/Makefile
View File

@ -27,13 +27,13 @@ endif
obj-y := cputable.o ptrace.o syscalls.o \
irq.o align.o signal_32.o pmc.o vdso.o \
init_task.o process.o systbl.o idle.o \
signal.o
signal.o sysfs.o
obj-y += vdso32/
obj-$(CONFIG_PPC64) += setup_64.o sys_ppc32.o \
signal_64.o ptrace32.o \
paca.o cpu_setup_ppc970.o \
cpu_setup_pa6t.o \
firmware.o sysfs.o nvram_64.o
firmware.o nvram_64.o
obj-$(CONFIG_PPC64) += vdso64/
obj-$(CONFIG_ALTIVEC) += vecemu.o vector.o
obj-$(CONFIG_PPC_970_NAP) += idle_power4.o

24
arch/powerpc/kernel/cputable.c
View File

@ -610,6 +610,7 @@ static struct cpu_spec __initdata cpu_specs[] = {
.icache_bsize = 32,
.dcache_bsize = 32,
.num_pmcs = 4,
.pmc_type = PPC_PMC_IBM,
.cpu_setup = __setup_cpu_750cx,
.machine_check = machine_check_generic,
.platform = "ppc750",
@ -623,6 +624,7 @@ static struct cpu_spec __initdata cpu_specs[] = {
.icache_bsize = 32,
.dcache_bsize = 32,
.num_pmcs = 4,
.pmc_type = PPC_PMC_IBM,
.cpu_setup = __setup_cpu_750cx,
.machine_check = machine_check_generic,
.platform = "ppc750",
@ -636,6 +638,7 @@ static struct cpu_spec __initdata cpu_specs[] = {
.icache_bsize = 32,
.dcache_bsize = 32,
.num_pmcs = 4,
.pmc_type = PPC_PMC_IBM,
.cpu_setup = __setup_cpu_750cx,
.machine_check = machine_check_generic,
.platform = "ppc750",
@ -649,6 +652,7 @@ static struct cpu_spec __initdata cpu_specs[] = {
.icache_bsize = 32,
.dcache_bsize = 32,
.num_pmcs = 4,
.pmc_type = PPC_PMC_IBM,
.cpu_setup = __setup_cpu_750,
.machine_check = machine_check_generic,
.platform = "ppc750",
@ -662,6 +666,7 @@ static struct cpu_spec __initdata cpu_specs[] = {
.icache_bsize = 32,
.dcache_bsize = 32,
.num_pmcs = 4,
.pmc_type = PPC_PMC_IBM,
.cpu_setup = __setup_cpu_750,
.machine_check = machine_check_generic,
.platform = "ppc750",
@ -675,6 +680,7 @@ static struct cpu_spec __initdata cpu_specs[] = {
.icache_bsize = 32,
.dcache_bsize = 32,
.num_pmcs = 4,
.pmc_type = PPC_PMC_IBM,
.cpu_setup = __setup_cpu_750,
.machine_check = machine_check_generic,
.platform = "ppc750",
@ -688,6 +694,7 @@ static struct cpu_spec __initdata cpu_specs[] = {
.icache_bsize = 32,
.dcache_bsize = 32,
.num_pmcs = 4,
.pmc_type = PPC_PMC_IBM,
.cpu_setup = __setup_cpu_750,
.machine_check = machine_check_generic,
.platform = "ppc750",
@ -701,6 +708,7 @@ static struct cpu_spec __initdata cpu_specs[] = {
.icache_bsize = 32,
.dcache_bsize = 32,
.num_pmcs = 4,
.pmc_type = PPC_PMC_IBM,
.cpu_setup = __setup_cpu_750fx,
.machine_check = machine_check_generic,
.platform = "ppc750",
@ -714,6 +722,7 @@ static struct cpu_spec __initdata cpu_specs[] = {
.icache_bsize = 32,
.dcache_bsize = 32,
.num_pmcs = 4,
.pmc_type = PPC_PMC_IBM,
.cpu_setup = __setup_cpu_750fx,
.machine_check = machine_check_generic,
.platform = "ppc750",
@ -727,6 +736,7 @@ static struct cpu_spec __initdata cpu_specs[] = {
.icache_bsize = 32,
.dcache_bsize = 32,
.num_pmcs = 4,
.pmc_type = PPC_PMC_IBM,
.cpu_setup = __setup_cpu_750,
.machine_check = machine_check_generic,
.platform = "ppc750",
@ -741,6 +751,7 @@ static struct cpu_spec __initdata cpu_specs[] = {
.icache_bsize = 32,
.dcache_bsize = 32,
.num_pmcs = 4,
.pmc_type = PPC_PMC_G4,
.cpu_setup = __setup_cpu_7400,
.machine_check = machine_check_generic,
.platform = "ppc7400",
@ -755,6 +766,7 @@ static struct cpu_spec __initdata cpu_specs[] = {
.icache_bsize = 32,
.dcache_bsize = 32,
.num_pmcs = 4,
.pmc_type = PPC_PMC_G4,
.cpu_setup = __setup_cpu_7400,
.machine_check = machine_check_generic,
.platform = "ppc7400",
@ -769,6 +781,7 @@ static struct cpu_spec __initdata cpu_specs[] = {
.icache_bsize = 32,
.dcache_bsize = 32,
.num_pmcs = 4,
.pmc_type = PPC_PMC_G4,
.cpu_setup = __setup_cpu_7410,
.machine_check = machine_check_generic,
.platform = "ppc7400",
@ -783,6 +796,7 @@ static struct cpu_spec __initdata cpu_specs[] = {
.icache_bsize = 32,
.dcache_bsize = 32,
.num_pmcs = 6,
.pmc_type = PPC_PMC_G4,
.cpu_setup = __setup_cpu_745x,
.oprofile_cpu_type = "ppc/7450",
.oprofile_type = PPC_OPROFILE_G4,
@ -799,6 +813,7 @@ static struct cpu_spec __initdata cpu_specs[] = {
.icache_bsize = 32,
.dcache_bsize = 32,
.num_pmcs = 6,
.pmc_type = PPC_PMC_G4,
.cpu_setup = __setup_cpu_745x,
.oprofile_cpu_type = "ppc/7450",
.oprofile_type = PPC_OPROFILE_G4,
@ -815,6 +830,7 @@ static struct cpu_spec __initdata cpu_specs[] = {
.icache_bsize = 32,
.dcache_bsize = 32,
.num_pmcs = 6,
.pmc_type = PPC_PMC_G4,
.cpu_setup = __setup_cpu_745x,
.oprofile_cpu_type = "ppc/7450",
.oprofile_type = PPC_OPROFILE_G4,
@ -831,6 +847,7 @@ static struct cpu_spec __initdata cpu_specs[] = {
.icache_bsize = 32,
.dcache_bsize = 32,
.num_pmcs = 6,
.pmc_type = PPC_PMC_G4,
.cpu_setup = __setup_cpu_745x,
.oprofile_cpu_type = "ppc/7450",
.oprofile_type = PPC_OPROFILE_G4,
@ -847,6 +864,7 @@ static struct cpu_spec __initdata cpu_specs[] = {
.icache_bsize = 32,
.dcache_bsize = 32,
.num_pmcs = 6,
.pmc_type = PPC_PMC_G4,
.cpu_setup = __setup_cpu_745x,
.oprofile_cpu_type = "ppc/7450",
.oprofile_type = PPC_OPROFILE_G4,
@ -863,6 +881,7 @@ static struct cpu_spec __initdata cpu_specs[] = {
.icache_bsize = 32,
.dcache_bsize = 32,
.num_pmcs = 6,
.pmc_type = PPC_PMC_G4,
.cpu_setup = __setup_cpu_745x,
.oprofile_cpu_type = "ppc/7450",
.oprofile_type = PPC_OPROFILE_G4,
@ -879,6 +898,7 @@ static struct cpu_spec __initdata cpu_specs[] = {
.icache_bsize = 32,
.dcache_bsize = 32,
.num_pmcs = 6,
.pmc_type = PPC_PMC_G4,
.cpu_setup = __setup_cpu_745x,
.oprofile_cpu_type = "ppc/7450",
.oprofile_type = PPC_OPROFILE_G4,
@ -895,6 +915,7 @@ static struct cpu_spec __initdata cpu_specs[] = {
.icache_bsize = 32,
.dcache_bsize = 32,
.num_pmcs = 6,
.pmc_type = PPC_PMC_G4,
.cpu_setup = __setup_cpu_745x,
.oprofile_cpu_type = "ppc/7450",
.oprofile_type = PPC_OPROFILE_G4,
@ -910,6 +931,7 @@ static struct cpu_spec __initdata cpu_specs[] = {
.icache_bsize = 32,
.dcache_bsize = 32,
.num_pmcs = 6,
.pmc_type = PPC_PMC_G4,
.cpu_setup = __setup_cpu_745x,
.oprofile_cpu_type = "ppc/7450",
.oprofile_type = PPC_OPROFILE_G4,
@ -926,6 +948,7 @@ static struct cpu_spec __initdata cpu_specs[] = {
.icache_bsize = 32,
.dcache_bsize = 32,
.num_pmcs = 6,
.pmc_type = PPC_PMC_G4,
.cpu_setup = __setup_cpu_745x,
.oprofile_cpu_type = "ppc/7450",
.oprofile_type = PPC_OPROFILE_G4,
@ -942,6 +965,7 @@ static struct cpu_spec __initdata cpu_specs[] = {
.icache_bsize = 32,
.dcache_bsize = 32,
.num_pmcs = 6,
.pmc_type = PPC_PMC_G4,
.cpu_setup = __setup_cpu_745x,
.oprofile_cpu_type = "ppc/7450",
.oprofile_type = PPC_OPROFILE_G4,

11
arch/powerpc/kernel/setup_32.c
View File

@ -209,23 +209,12 @@ EXPORT_SYMBOL(nvram_sync);
#endif /* CONFIG_NVRAM */
static DEFINE_PER_CPU(struct cpu, cpu_devices);
int __init ppc_init(void)
{
int cpu;
/* clear the progress line */
if (ppc_md.progress)
ppc_md.progress(" ", 0xffff);
/* register CPU devices */
for_each_possible_cpu(cpu) {
struct cpu *c = &per_cpu(cpu_devices, cpu);
c->hotpluggable = 1;
register_cpu(c, cpu);
}
/* call platform init */
if (ppc_md.init != NULL) {
ppc_md.init();

106
arch/powerpc/kernel/sysfs.c
View File

@ -15,18 +15,24 @@
#include <asm/firmware.h>
#include <asm/hvcall.h>
#include <asm/prom.h>
#include <asm/paca.h>
#include <asm/lppaca.h>
#include <asm/machdep.h>
#include <asm/smp.h>
#ifdef CONFIG_PPC64
#include <asm/paca.h>
#include <asm/lppaca.h>
#endif
static DEFINE_PER_CPU(struct cpu, cpu_devices);
static DEFINE_PER_CPU(struct kobject *, cache_toplevel);
/* SMT stuff */
/*
* SMT snooze delay stuff, 64-bit only for now
*/
#ifdef CONFIG_PPC64
#ifdef CONFIG_PPC_MULTIPLATFORM
/* Time in microseconds we delay before sleeping in the idle loop */
DEFINE_PER_CPU(unsigned long, smt_snooze_delay) = { 100 };
@ -106,7 +112,7 @@ static int __init setup_smt_snooze_delay(char *str)
}
__setup("smt-snooze-delay=", setup_smt_snooze_delay);
#endif /* CONFIG_PPC_MULTIPLATFORM */
#endif /* CONFIG_PPC64 */
/*
* Enabling PMCs will slow partition context switch times so we only do
@ -115,7 +121,7 @@ __setup("smt-snooze-delay=", setup_smt_snooze_delay);
static DEFINE_PER_CPU(char, pmcs_enabled);
void ppc64_enable_pmcs(void)
void ppc_enable_pmcs(void)
{
/* Only need to enable them once */
if (__get_cpu_var(pmcs_enabled))
@ -126,7 +132,7 @@ void ppc64_enable_pmcs(void)
if (ppc_md.enable_pmcs)
ppc_md.enable_pmcs();
}
EXPORT_SYMBOL(ppc64_enable_pmcs);
EXPORT_SYMBOL(ppc_enable_pmcs);
/* XXX convert to rusty's on_one_cpu */
static unsigned long run_on_cpu(unsigned long cpu,
@ -154,7 +160,7 @@ static unsigned long read_##NAME(unsigned long junk) \
} \
static unsigned long write_##NAME(unsigned long val) \
{ \
ppc64_enable_pmcs(); \
ppc_enable_pmcs(); \
mtspr(ADDRESS, val); \
return 0; \
} \
@ -184,28 +190,53 @@ static ssize_t __used \
* that are implemented on the current processor
*/
#ifdef CONFIG_PPC64
#define HAS_PPC_PMC_CLASSIC 1
#define HAS_PPC_PMC_IBM 1
#define HAS_PPC_PMC_PA6T 1
#elif CONFIG_6xx
#define HAS_PPC_PMC_CLASSIC 1
#define HAS_PPC_PMC_IBM 1
#define HAS_PPC_PMC_G4 1
#endif
#ifdef HAS_PPC_PMC_CLASSIC
SYSFS_PMCSETUP(mmcr0, SPRN_MMCR0);
SYSFS_PMCSETUP(mmcr1, SPRN_MMCR1);
SYSFS_PMCSETUP(mmcra, SPRN_MMCRA);
SYSFS_PMCSETUP(pmc1, SPRN_PMC1);
SYSFS_PMCSETUP(pmc2, SPRN_PMC2);
SYSFS_PMCSETUP(pmc3, SPRN_PMC3);
SYSFS_PMCSETUP(pmc4, SPRN_PMC4);
SYSFS_PMCSETUP(pmc5, SPRN_PMC5);
SYSFS_PMCSETUP(pmc6, SPRN_PMC6);
#ifdef HAS_PPC_PMC_G4
SYSFS_PMCSETUP(mmcr2, SPRN_MMCR2);
#endif
#ifdef CONFIG_PPC64
SYSFS_PMCSETUP(pmc7, SPRN_PMC7);
SYSFS_PMCSETUP(pmc8, SPRN_PMC8);
SYSFS_PMCSETUP(mmcra, SPRN_MMCRA);
SYSFS_PMCSETUP(purr, SPRN_PURR);
SYSFS_PMCSETUP(spurr, SPRN_SPURR);
SYSFS_PMCSETUP(dscr, SPRN_DSCR);
static SYSDEV_ATTR(mmcra, 0600, show_mmcra, store_mmcra);
static SYSDEV_ATTR(spurr, 0600, show_spurr, NULL);
static SYSDEV_ATTR(dscr, 0600, show_dscr, store_dscr);
static SYSDEV_ATTR(purr, 0600, show_purr, store_purr);
#endif /* CONFIG_PPC64 */
#ifdef HAS_PPC_PMC_PA6T
SYSFS_PMCSETUP(pa6t_pmc0, SPRN_PA6T_PMC0);
SYSFS_PMCSETUP(pa6t_pmc1, SPRN_PA6T_PMC1);
SYSFS_PMCSETUP(pa6t_pmc2, SPRN_PA6T_PMC2);
SYSFS_PMCSETUP(pa6t_pmc3, SPRN_PA6T_PMC3);
SYSFS_PMCSETUP(pa6t_pmc4, SPRN_PA6T_PMC4);
SYSFS_PMCSETUP(pa6t_pmc5, SPRN_PA6T_PMC5);
#ifdef CONFIG_DEBUG_KERNEL
SYSFS_PMCSETUP(hid0, SPRN_HID0);
SYSFS_PMCSETUP(hid1, SPRN_HID1);
@ -236,28 +267,37 @@ SYSFS_PMCSETUP(tsr1, SPRN_PA6T_TSR1);
SYSFS_PMCSETUP(tsr2, SPRN_PA6T_TSR2);
SYSFS_PMCSETUP(tsr3, SPRN_PA6T_TSR3);
#endif /* CONFIG_DEBUG_KERNEL */
#endif /* HAS_PPC_PMC_PA6T */
static SYSDEV_ATTR(mmcra, 0600, show_mmcra, store_mmcra);
static SYSDEV_ATTR(spurr, 0600, show_spurr, NULL);
static SYSDEV_ATTR(dscr, 0600, show_dscr, store_dscr);
static SYSDEV_ATTR(purr, 0600, show_purr, store_purr);
#ifdef HAS_PPC_PMC_IBM
static struct sysdev_attribute ibm_common_attrs[] = {
_SYSDEV_ATTR(mmcr0, 0600, show_mmcr0, store_mmcr0),
_SYSDEV_ATTR(mmcr1, 0600, show_mmcr1, store_mmcr1),
};
#endif /* HAS_PPC_PMC_G4 */
static struct sysdev_attribute ibm_pmc_attrs[] = {
#ifdef HAS_PPC_PMC_G4
static struct sysdev_attribute g4_common_attrs[] = {
_SYSDEV_ATTR(mmcr0, 0600, show_mmcr0, store_mmcr0),
_SYSDEV_ATTR(mmcr1, 0600, show_mmcr1, store_mmcr1),
_SYSDEV_ATTR(mmcr2, 0600, show_mmcr2, store_mmcr2),
};
#endif /* HAS_PPC_PMC_G4 */
static struct sysdev_attribute classic_pmc_attrs[] = {
_SYSDEV_ATTR(pmc1, 0600, show_pmc1, store_pmc1),
_SYSDEV_ATTR(pmc2, 0600, show_pmc2, store_pmc2),
_SYSDEV_ATTR(pmc3, 0600, show_pmc3, store_pmc3),
_SYSDEV_ATTR(pmc4, 0600, show_pmc4, store_pmc4),
_SYSDEV_ATTR(pmc5, 0600, show_pmc5, store_pmc5),
_SYSDEV_ATTR(pmc6, 0600, show_pmc6, store_pmc6),
#ifdef CONFIG_PPC64
_SYSDEV_ATTR(pmc7, 0600, show_pmc7, store_pmc7),
_SYSDEV_ATTR(pmc8, 0600, show_pmc8, store_pmc8),
#endif
};
#ifdef HAS_PPC_PMC_PA6T
static struct sysdev_attribute pa6t_attrs[] = {
_SYSDEV_ATTR(mmcr0, 0600, show_mmcr0, store_mmcr0),
_SYSDEV_ATTR(mmcr1, 0600, show_mmcr1, store_mmcr1),
@ -298,6 +338,8 @@ static struct sysdev_attribute pa6t_attrs[] = {
_SYSDEV_ATTR(tsr3, 0600, show_tsr3, store_tsr3),
#endif /* CONFIG_DEBUG_KERNEL */
};
#endif /* HAS_PPC_PMC_PA6T */
#endif /* HAS_PPC_PMC_CLASSIC */
struct cache_desc {
struct kobject kobj;
@ -588,23 +630,36 @@ static void __cpuinit register_cpu_online(unsigned int cpu)
struct sysdev_attribute *attrs, *pmc_attrs;
int i, nattrs;
#ifdef CONFIG_PPC64
if (!firmware_has_feature(FW_FEATURE_ISERIES) &&
cpu_has_feature(CPU_FTR_SMT))
sysdev_create_file(s, &attr_smt_snooze_delay);
#endif
/* PMC stuff */
switch (cur_cpu_spec->pmc_type) {
#ifdef HAS_PPC_PMC_IBM
case PPC_PMC_IBM:
attrs = ibm_common_attrs;
nattrs = sizeof(ibm_common_attrs) / sizeof(struct sysdev_attribute);
pmc_attrs = ibm_pmc_attrs;
pmc_attrs = classic_pmc_attrs;
break;
#endif /* HAS_PPC_PMC_IBM */
#ifdef HAS_PPC_PMC_G4
case PPC_PMC_G4:
attrs = g4_common_attrs;
nattrs = sizeof(g4_common_attrs) / sizeof(struct sysdev_attribute);
pmc_attrs = classic_pmc_attrs;
break;
#endif /* HAS_PPC_PMC_G4 */
#ifdef HAS_PPC_PMC_PA6T
case PPC_PMC_PA6T:
/* PA Semi starts counting at PMC0 */
attrs = pa6t_attrs;
nattrs = sizeof(pa6t_attrs) / sizeof(struct sysdev_attribute);
pmc_attrs = NULL;
break;
#endif /* HAS_PPC_PMC_PA6T */
default:
attrs = NULL;
nattrs = 0;
@ -618,6 +673,7 @@ static void __cpuinit register_cpu_online(unsigned int cpu)
for (i = 0; i < cur_cpu_spec->num_pmcs; i++)
sysdev_create_file(s, &pmc_attrs[i]);
#ifdef CONFIG_PPC64
if (cpu_has_feature(CPU_FTR_MMCRA))
sysdev_create_file(s, &attr_mmcra);
@ -629,6 +685,7 @@ static void __cpuinit register_cpu_online(unsigned int cpu)
if (cpu_has_feature(CPU_FTR_DSCR))
sysdev_create_file(s, &attr_dscr);
#endif /* CONFIG_PPC64 */
create_cache_info(s);
}
@ -664,17 +721,28 @@ static void unregister_cpu_online(unsigned int cpu)
/* PMC stuff */
switch (cur_cpu_spec->pmc_type) {
#ifdef HAS_PPC_PMC_IBM
case PPC_PMC_IBM:
attrs = ibm_common_attrs;
nattrs = sizeof(ibm_common_attrs) / sizeof(struct sysdev_attribute);
pmc_attrs = ibm_pmc_attrs;
pmc_attrs = classic_pmc_attrs;
break;
#endif /* HAS_PPC_PMC_IBM */
#ifdef HAS_PPC_PMC_G4
case PPC_PMC_G4:
attrs = g4_common_attrs;
nattrs = sizeof(g4_common_attrs) / sizeof(struct sysdev_attribute);
pmc_attrs = classic_pmc_attrs;
break;
#endif /* HAS_PPC_PMC_G4 */
#ifdef HAS_PPC_PMC_PA6T
case PPC_PMC_PA6T:
/* PA Semi starts counting at PMC0 */
attrs = pa6t_attrs;
nattrs = sizeof(pa6t_attrs) / sizeof(struct sysdev_attribute);
pmc_attrs = NULL;
break;
#endif /* HAS_PPC_PMC_PA6T */
default:
attrs = NULL;
nattrs = 0;
@ -688,6 +756,7 @@ static void unregister_cpu_online(unsigned int cpu)
for (i = 0; i < cur_cpu_spec->num_pmcs; i++)
sysdev_remove_file(s, &pmc_attrs[i]);
#ifdef CONFIG_PPC64
if (cpu_has_feature(CPU_FTR_MMCRA))
sysdev_remove_file(s, &attr_mmcra);
@ -699,6 +768,7 @@ static void unregister_cpu_online(unsigned int cpu)
if (cpu_has_feature(CPU_FTR_DSCR))
sysdev_remove_file(s, &attr_dscr);
#endif /* CONFIG_PPC64 */
remove_cache_info(s);
}

4
arch/powerpc/oprofile/op_model_power4.c
View File

@ -64,7 +64,7 @@ static int power4_reg_setup(struct op_counter_config *ctr,
return 0;
}
extern void ppc64_enable_pmcs(void);
extern void ppc_enable_pmcs(void);
/*
* Older CPUs require the MMCRA sample bit to be always set, but newer
@ -91,7 +91,7 @@ static int power4_cpu_setup(struct op_counter_config *ctr)
unsigned int mmcr0 = mmcr0_val;
unsigned long mmcra = mmcra_val;
ppc64_enable_pmcs();
ppc_enable_pmcs();
/* set the freeze bit */
mmcr0 |= MMCR0_FC;