- 根目录:
- arch
- powerpc
- kernel
- power4-pmu.c
/*
* Performance counter support for POWER4 (GP) and POWER4+ (GQ) processors.
*
* Copyright 2009 Paul Mackerras, IBM Corporation.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/kernel.h>
#include <linux/perf_event.h>
#include <linux/string.h>
#include <asm/reg.h>
#include <asm/cputable.h>
/*
* Bits in event code for POWER4
*/
#define PM_PMC_SH 12 /* PMC number (1-based) for direct events */
#define PM_PMC_MSK 0xf
#define PM_UNIT_SH 8 /* TTMMUX number and setting - unit select */
#define PM_UNIT_MSK 0xf
#define PM_LOWER_SH 6
#define PM_LOWER_MSK 1
#define PM_LOWER_MSKS 0x40
#define PM_BYTE_SH 4 /* Byte number of event bus to use */
#define PM_BYTE_MSK 3
#define PM_PMCSEL_MSK 7
/*
* Unit code values
*/
#define PM_FPU 1
#define PM_ISU1 2
#define PM_IFU 3
#define PM_IDU0 4
#define PM_ISU1_ALT 6
#define PM_ISU2 7
#define PM_IFU_ALT 8
#define PM_LSU0 9
#define PM_LSU1 0xc
#define PM_GPS 0xf
/*
* Bits in MMCR0 for POWER4
*/
#define MMCR0_PMC1SEL_SH 8
#define MMCR0_PMC2SEL_SH 1
#define MMCR_PMCSEL_MSK 0x1f
/*
* Bits in MMCR1 for POWER4
*/
#define MMCR1_TTM0SEL_SH 62
#define MMCR1_TTC0SEL_SH 61
#define MMCR1_TTM1SEL_SH 59
#define MMCR1_TTC1SEL_SH 58
#define MMCR1_TTM2SEL_SH 56
#define MMCR1_TTC2SEL_SH 55
#define MMCR1_TTM3SEL_SH 53
#define MMCR1_TTC3SEL_SH 52
#define MMCR1_TTMSEL_MSK 3
#define MMCR1_TD_CP_DBG0SEL_SH 50
#define MMCR1_TD_CP_DBG1SEL_SH 48
#define MMCR1_TD_CP_DBG2SEL_SH 46
#define MMCR1_TD_CP_DBG3SEL_SH 44
#define MMCR1_DEBUG0SEL_SH 43
#define MMCR1_DEBUG1SEL_SH 42
#define MMCR1_DEBUG2SEL_SH 41
#define MMCR1_DEBUG3SEL_SH 40
#define MMCR1_PMC1_ADDER_SEL_SH 39
#define MMCR1_PMC2_ADDER_SEL_SH 38
#define MMCR1_PMC6_ADDER_SEL_SH 37
#define MMCR1_PMC5_ADDER_SEL_SH 36
#define MMCR1_PMC8_ADDER_SEL_SH 35
#define MMCR1_PMC7_ADDER_SEL_SH 34
#define MMCR1_PMC3_ADDER_SEL_SH 33
#define MMCR1_PMC4_ADDER_SEL_SH 32
#define MMCR1_PMC3SEL_SH 27
#define MMCR1_PMC4SEL_SH 22
#define MMCR1_PMC5SEL_SH 17
#define MMCR1_PMC6SEL_SH 12
#define MMCR1_PMC7SEL_SH 7
#define MMCR1_PMC8SEL_SH 2 /* note bit 0 is in MMCRA for GP */
static short mmcr1_adder_bits[8] = {
MMCR1_PMC1_ADDER_SEL_SH,
MMCR1_PMC2_ADDER_SEL_SH,
MMCR1_PMC3_ADDER_SEL_SH,
MMCR1_PMC4_ADDER_SEL_SH,
MMCR1_PMC5_ADDER_SEL_SH,
MMCR1_PMC6_ADDER_SEL_SH,
MMCR1_PMC7_ADDER_SEL_SH,
MMCR1_PMC8_ADDER_SEL_SH
};
/*
* Bits in MMCRA
*/
#define MMCRA_PMC8SEL0_SH 17 /* PMC8SEL bit 0 for GP */
/*
* Layout of constraint bits:
* 6666555555555544444444443333333333222222222211111111110000000000
* 3210987654321098765432109876543210987654321098765432109876543210
* |[ >[ >[ >|||[ >[ >< >< >< >< ><><><><><><><><>
* | UC1 UC2 UC3 ||| PS1 PS2 B0 B1 B2 B3 P1P2P3P4P5P6P7P8
* \SMPL ||\TTC3SEL
* |\TTC_IFU_SEL
* \TTM2SEL0
*
* SMPL - SAMPLE_ENABLE constraint
* 56: SAMPLE_ENABLE value 0x0100_0000_0000_0000
*
* UC1 - unit constraint 1: can't have all three of FPU/ISU1/IDU0|ISU2
* 55: UC1 error 0x0080_0000_0000_0000
* 54: FPU events needed 0x0040_0000_0000_0000
* 53: ISU1 events needed 0x0020_0000_0000_0000
* 52: IDU0|ISU2 events needed 0x0010_0000_0000_0000
*
* UC2 - unit constraint 2: can't have all three of FPU/IFU/LSU0
* 51: UC2 error 0x0008_0000_0000_0000
* 50: FPU events needed 0x0004_0000_0000_0000
* 49: IFU events needed 0x0002_0000_0000_0000
* 48: LSU0 events needed 0x0001_0000_0000_0000
*
* UC3 - unit constraint 3: can't have all four of LSU0/IFU/IDU0|ISU2/ISU1
* 47: UC3 error 0x8000_0000_0000
* 46: LSU0 events needed 0x4000_0000_0000
* 45: IFU events needed 0x2000_0000_0000
* 44: IDU0|ISU2 events needed 0x1000_0000_0000
* 43: ISU1 events needed 0x0800_0000_0000
*
* TTM2SEL0
* 42: 0 = IDU0 events needed
* 1 = ISU2 events needed 0x0400_0000_0000
*
* TTC_IFU_SEL
* 41: 0 = IFU.U events needed
* 1 = IFU.L events needed 0x0200_0000_0000
*
* TTC3SEL
* 40: 0 = LSU1.U events needed
* 1 = LSU1.L events needed 0x0100_0000_0000
*
* PS1
* 39: PS1 error 0x0080_0000_0000
* 36-38: count of events needing PMC1/2/5/6 0x0070_0000_0000
*
* PS2
* 35: PS2 error 0x0008_0000_0000
* 32-34: count of events needing PMC3/4/7/8 0x0007_0000_0000
*
* B0
* 28-31: Byte 0 event source 0xf000_0000
* 1 = FPU
* 2 = ISU1
* 3 = IFU
* 4 = IDU0
* 7 = ISU2
* 9 = LSU0
* c = LSU1
* f = GPS
*
* B1, B2, B3
* 24-27, 20-23, 16-19: Byte 1, 2, 3 event sources
*
* P8
* 15: P8 error 0x8000
* 14-15: Count of events needing PMC8
*
* P1..P7
* 0-13: Count of events needing PMC1..PMC7
*
* Note: this doesn't allow events using IFU.U to be combined with events
* using IFU.L, though that is feasible (using TTM0 and TTM2). However
* there are no listed events for IFU.L (they are debug events not
* verified for performance monitoring) so this shouldn't cause a
* problem.
*/
static struct unitinfo {
unsigned long value, mask;
int unit;
int lowerbit;
} p4_unitinfo[16] = {
[PM_FPU] = { 0x44000000000000ul, 0x88000000000000ul, PM_FPU, 0 },
[PM_ISU1] = { 0x20080000000000ul, 0x88000000000000ul, PM_ISU1, 0 },
[PM_ISU1_ALT] =
{ 0x20080000000000ul, 0x88000000000000ul, PM_ISU1, 0 },
[PM_IFU] = { 0x02200000000000ul, 0x08820000000000ul, PM_IFU, 41 },
[PM_IFU_ALT] =
{ 0x02200000000000ul, 0x08820000000000ul, PM_IFU, 41 },
[PM_IDU0] = { 0x10100000000000ul, 0x80840000000000ul, PM_IDU0, 1 },
[PM_ISU2] = { 0x10140000000000ul, 0x80840000000000ul, PM_ISU2, 0 },
[PM_LSU0] = { 0x01400000000000ul, 0x08800000000000ul, PM_LSU0, 0 },
[PM_LSU1] = { 0x00000000000000ul, 0x00010000000000ul, PM_LSU1, 40 },
[PM_GPS] = { 0x00000000000000ul, 0x00000000000000ul, PM_GPS, 0 }
};
static unsigned char direct_marked_event[8] = {
(1<<2) | (1<<3), /* PMC1: PM_MRK_GRP_DISP, PM_MRK_ST_CMPL */
(1<<3) | (1<<5), /* PMC2: PM_THRESH_TIMEO, PM_MRK_BRU_FIN */
(1<<3), /* PMC3: PM_MRK_ST_CMPL_INT */
(1<<4) | (1<<5), /* PMC4: PM_MRK_GRP_CMPL, PM_MRK_CRU_FIN */
(1<<4) | (1<<5), /* PMC5: PM_MRK_GRP_TIMEO */
(1<<3) | (1<<4) | (1<<5),
/* PMC6: PM_MRK_ST_GPS, PM_MRK_FXU_FIN, PM_MRK_GRP_ISSUED */
(1<<4) | (1<<5), /* PMC7: PM_MRK_FPU_FIN, PM_MRK_INST_FIN */
(1<<4), /* PMC8: PM_MRK_LSU_FIN */
};
/*
* Returns 1 if event counts things relating to marked instructions
* and thus needs the MMCRA_SAMPLE_ENABLE bit set, or 0 if not.
*/
static int p4_marked_instr_event(u64 event)
{
int pmc, psel, unit, byte, bit;
unsigned int mask;
pmc = (event >> PM_PMC_SH) & PM_PMC_MSK;
psel = event & PM_PMCSEL_MSK;
if (pmc) {
if (direct_marked_event[pmc - 1] & (1 << psel))
return 1;
if (psel == 0) /* add events */
bit = (pmc <= 4)? pmc - 1: 8 - pmc;
else if (psel == 6) /* decode events */
bit = 4;
else
return 0;
} else
bit = psel;
byte = (event >> PM_BYTE_SH) & PM_BYTE_MSK;
unit = (event >> PM_UNIT_SH) & PM_UNIT_MSK;
mask = 0;
switch (unit) {
case PM_LSU1:
if (event & PM_LOWER_MSKS)
mask = 1 << 28; /* byte 7 bit 4 */
else
mask = 6 << 24; /* byte 3 bits 1 and 2 */
break;
case PM_LSU0:
/* byte 3, bit 3; byte 2 bits 0,2,3,4,5; byte 1 */
mask = 0x083dff00;
}
return (mask >> (byte * 8 + bit)) & 1;
}
static int p4_get_constraint(u64 event, unsigned long *maskp,
unsigned long *valp)
{
int pmc, byte, unit, lower, sh;
unsigned long mask = 0, value = 0;
int grp = -1;
pmc = (event >> PM_PMC_SH) & PM_PMC_MSK;
if (pmc) {
if (pmc > 8)
return -1;
sh = (pmc - 1) * 2;
mask |= 2 << sh;
value |= 1 << sh;
grp = ((pmc - 1) >> 1) & 1;
}
unit = (event >> PM_UNIT_SH) & PM_UNIT_MSK;
byte = (event >> PM_BYTE_SH) & PM_BYTE_MSK;
if (unit) {
lower = (event >> PM_LOWER_SH) & PM_LOWER_MSK;
/*
* Bus events on bytes 0 and 2 can be counted
* on PMC1/2/5/6; bytes 1 and 3 on PMC3/4/7/8.
*/
if (!pmc)
grp = byte & 1;
if (!p4_unitinfo[unit].unit)
return -1;
mask |= p4_unitinfo[unit].mask;
value |= p4_unitinfo[unit].value;
sh = p4_unitinfo[unit].lowerbit;
if (sh > 1)
value |= (unsigned long)lower << sh;
else if (lower != sh)
return -1;
unit = p4_unitinfo[unit].unit;
/* Set byte lane select field */
mask |= 0xfULL << (28 - 4 * byte);
value |= (unsigned long)unit << (28 - 4 * byte);
}
if (grp == 0) {
/* increment PMC1/2/5/6 field */
mask |= 0x8000000000ull;
value |= 0x1000000000ull;
} else {
/* increment PMC3/4/7/8 field */
mask |= 0x800000000ull;
value |= 0x100000000ull;
}
/* Marked instruction events need sample_enable set */
if (p4_marked_instr_event(event)) {
mask |= 1ull << 56;
value |= 1ull << 56;
}
/* PMCSEL=6 decode events on byte 2 need sample_enable clear */
if (pmc && (event & PM_PMCSEL_MSK) == 6 && byte == 2)
mask |= 1ull << 56;
*maskp = mask;
*valp = value;
return 0;
}
static unsigned int ppc_inst_cmpl[] = {
0x1001, 0x4001, 0x6001, 0x7001, 0x8001
};
static int p4_get_alternatives(u64 event, unsigned int flags, u64 alt[])
{
int i, j, na;
alt[0] = event;
na = 1;
/* 2 possibilities for PM_GRP_DISP_REJECT */
if (event == 0x8003 || event == 0x0224) {
alt[1] = event ^ (0x8003 ^ 0x0224);
return 2;
}
/* 2 possibilities for PM_ST_MISS_L1 */
if (event == 0x0c13 || event == 0x0c23) {
alt[1] = event ^ (0x0c13 ^ 0x0c23);
return 2;
}
/* several possibilities for PM_INST_CMPL */
for (i = 0; i < ARRAY_SIZE(ppc_inst_cmpl); ++i) {
if (event == ppc_inst_cmpl[i]) {
for (j = 0; j < ARRAY_SIZE(ppc_inst_cmpl); ++j)
if (j != i)
alt[na++] = ppc_inst_cmpl[j];
break;
}
}
return na;
}
static int p4_compute_mmcr(u64 event[], int n_ev,
unsigned int hwc[], unsigned long mmcr[])
{
unsigned long mmcr0 = 0, mmcr1 = 0, mmcra = 0;
unsigned int pmc, unit, byte, psel, lower;
unsigned int ttm, grp;
unsigned int pmc_inuse = 0;
unsigned int pmc_grp_use[2];
unsigned char busbyte[4];
unsigned char unituse[16];
unsigned int unitlower = 0;
int i;
if (n_ev > 8)
return -1;
/* First pass to count resource use */
pmc_grp_use[0] = pmc_grp_use[1] = 0;
memset(busbyte, 0, sizeof(busbyte));
memset(unituse, 0, sizeof(unituse));
for (i = 0; i < n_ev; ++i) {
pmc = (event[i] >> PM_PMC_SH) & PM_PMC_MSK;
if (pmc) {
if (pmc_inuse & (1 << (pmc - 1)))
return -1;
pmc_inuse |= 1 << (pmc - 1);
/* count 1/2/5/6 vs 3/4/7/8 use */
++pmc_grp_use[((pmc - 1) >> 1) & 1];
}
unit = (event[i] >> PM_UNIT_SH) & PM_UNIT_MSK;
byte = (event[i] >> PM_BYTE_SH) & PM_BYTE_MSK;
lower = (event[i] >> PM_LOWER_SH) & PM_LOWER_MSK;
if (unit) {
if (!pmc)
++pmc_grp_use[byte & 1];
if (unit == 6 || unit == 8)
/* map alt ISU1/IFU codes: 6->2, 8->3 */
unit = (unit >> 1) - 1;
if (busbyte[byte] && busbyte[byte] != unit)
return -1;
busbyte[byte] = unit;
lower <<= unit;
if (unituse[unit] && lower != (unitlower & lower))
return -1;
unituse[unit] = 1;
unitlower |= lower;
}
}
if (pmc_grp_use[0] > 4 || pmc_grp_use[1] > 4)
return -1;
/*
* Assign resources and set multiplexer selects.
*
* Units 1,2,3 are on TTM0, 4,6,7 on TTM1, 8,10 on TTM2.
* Each TTMx can only select one unit, but since
* units 2 and 6 are both ISU1, and 3 and 8 are both IFU,
* we have some choices.
*/
if (unituse[2] & (unituse[1] | (unituse[3] & unituse[9]))) {
unituse[6] = 1; /* Move 2 to 6 */
unituse[2] = 0;
}
if (unituse[3] & (unituse[1] | unituse[2])) {
unituse[8] = 1; /* Move 3 to 8 */
unituse[3] = 0;
unitlower = (unitlower & ~8) | ((unitlower & 8) << 5);
}
/* Check only one unit per TTMx */
if (unituse[1] + unituse[2] + unituse[3] > 1 ||
unituse[4] + unituse[6] + unituse[7] > 1 ||
unituse[8] + unituse[9] > 1 ||
(unituse[5] | unituse[10] | unituse[11] |
unituse[13] | unituse[14]))
return -1;
/* Set TTMxSEL fields. Note, units 1-3 => TTM0SEL codes 0-2 */
mmcr1 |= (unsigned long)(unituse[3] * 2 + unituse[2])
<< MMCR1_TTM0SEL_SH;
mmcr1 |= (unsigned long)(unituse[7] * 3 + unituse[6] * 2)
<< MMCR1_TTM1SEL_SH;
mmcr1 |= (unsigned long)unituse[9] << MMCR1_TTM2SEL_SH;
/* Set TTCxSEL fields. */
if (unitlower & 0xe)
mmcr1 |= 1ull << MMCR1_TTC0SEL_SH;
if (unitlower & 0xf0)
mmcr1 |= 1ull << MMCR1_TTC1SEL_SH;
if (unitlower & 0xf00)
mmcr1 |= 1ull << MMCR1_TTC2SEL_SH;
if (unitlower & 0x7000)
mmcr1 |= 1ull << MMCR1_TTC3SEL_SH;
/* Set byte lane select fields. */
for (byte = 0; byte < 4; ++byte) {
unit = busbyte[byte];
if (!unit)
continue;
if (unit == 0xf) {
/* special case for GPS */
mmcr1 |= 1ull << (MMCR1_DEBUG0SEL_SH - byte);
} else {
if (!unituse[unit])
ttm = unit - 1; /* 2->1, 3->2 */
else
ttm = unit >> 2;
mmcr1 |= (unsigned long)ttm
<< (MMCR1_TD_CP_DBG0SEL_SH - 2 * byte);
}
}
/* Second pass: assign PMCs, set PMCxSEL and PMCx_ADDER_SEL fields */
for (i = 0; i < n_ev; ++i) {
pmc = (event[i] >> PM_PMC_SH) & PM_PMC_MSK;
unit = (event[i] >> PM_UNIT_SH) & PM_UNIT_MSK;
byte = (event[i] >> PM_BYTE_SH) & PM_BYTE_MSK;
psel = event[i] & PM_PMCSEL_MSK;
if (!pmc) {
/* Bus event or 00xxx direct event (off or cycles) */
if (unit)
psel |= 0x10 | ((byte & 2) << 2);
for (pmc = 0; pmc < 8; ++pmc) {
if (pmc_inuse & (1 << pmc))
continue;
grp = (pmc >> 1) & 1;
if (unit) {
if (grp == (byte & 1))
break;
} else if (pmc_grp_use[grp] < 4) {
++pmc_grp_use[grp];
break;
}
}
pmc_inuse |= 1 << pmc;
} else {
/* Direct event */
--pmc;
if (psel == 0 && (byte & 2))
/* add events on higher-numbered bus */
mmcr1 |= 1ull << mmcr1_adder_bits[pmc];
else if (psel == 6 && byte == 3)
/* seem to need to set sample_enable here */
mmcra |= MMCRA_SAMPLE_ENABLE;
psel |= 8;
}
if (pmc <= 1)
mmcr0 |= psel << (MMCR0_PMC1SEL_SH - 7 * pmc);
else
mmcr1 |= psel << (MMCR1_PMC3SEL_SH - 5 * (pmc - 2));
if (pmc == 7) /* PMC8 */
mmcra |= (psel & 1) << MMCRA_PMC8SEL0_SH;
hwc[i] = pmc;
if (p4_marked_instr_event(event[i]))
mmcra |= MMCRA_SAMPLE_ENABLE;
}
if (pmc_inuse & 1)
mmcr0 |= MMCR0_PMC1CE;
if (pmc_inuse & 0xfe)
mmcr0 |= MMCR0_PMCjCE;
mmcra |= 0x2000; /* mark only one IOP per PPC instruction */
/* Return MMCRx values */
mmcr[0] = mmcr0;
mmcr[1] = mmcr1;
mmcr[2] = mmcra;
return 0;
}
static void p4_disable_pmc(unsigned int pmc, unsigned long mmcr[])
{
/*
* Setting the PMCxSEL field to 0 disables PMC x.
* (Note that pmc is 0-based here, not 1-based.)
*/
if (pmc <= 1) {
mmcr[0] &= ~(0x1fUL << (MMCR0_PMC1SEL_SH - 7 * pmc));
} else {
mmcr[1] &= ~(0x1fUL << (MMCR1_PMC3SEL_SH - 5 * (pmc - 2)));
if (pmc == 7)
mmcr[2] &= ~(1UL << MMCRA_PMC8SEL0_SH);
}
}
static int p4_generic_events[] = {
[PERF_COUNT_HW_CPU_CYCLES] = 7,
[PERF_COUNT_HW_INSTRUCTIONS] = 0x1001,
[PERF_COUNT_HW_CACHE_REFERENCES] = 0x8c10, /* PM_LD_REF_L1 */
[PERF_COUNT_HW_CACHE_MISSES] = 0x3c10, /* PM_LD_MISS_L1 */
[PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = 0x330, /* PM_BR_ISSUED */
[PERF_COUNT_HW_BRANCH_MISSES] = 0x331, /* PM_BR_MPRED_CR */
};
#define C(x) PERF_COUNT_HW_CACHE_##x
/*
* Table of generalized cache-related events.
* 0 means not supported, -1 means nonsensical, other values
* are event codes.
*/
static int power4_cache_events[C(MAX)][C(OP_MAX)][C(RESULT_MAX)] = {
[C(L1D)] = { /* RESULT_ACCESS RESULT_MISS */
[C(OP_READ)] = { 0x8c10, 0x3c10 },
[C(OP_WRITE)] = { 0x7c10, 0xc13 },
[C(OP_PREFETCH)] = { 0xc35, 0 },
},
[C(L1I)] = { /* RESULT_ACCESS RESULT_MISS */
[C(OP_READ)] = { 0, 0 },
[C(OP_WRITE)] = { -1, -1 },
[C(OP_PREFETCH)] = { 0, 0 },
},
[C(LL)] = { /* RESULT_ACCESS RESULT_MISS */
[C(OP_READ)] = { 0, 0 },
[C(OP_WRITE)] = { 0, 0 },
[C(OP_PREFETCH)] = { 0xc34, 0 },
},
[C(DTLB)] = { /* RESULT_ACCESS RESULT_MISS */
[C(OP_READ)] = { 0, 0x904 },
[C(OP_WRITE)] = { -1, -1 },
[C(OP_PREFETCH)] = { -1, -1 },
},
[C(ITLB)] = { /* RESULT_ACCESS RESULT_MISS */
[C(OP_READ)] = { 0, 0x900 },
[C(OP_WRITE)] = { -1, -1 },
[C(OP_PREFETCH)] = { -1, -1 },
},
[C(BPU)] = { /* RESULT_ACCESS RESULT_MISS */
[C(OP_READ)] = { 0x330, 0x331 },
[C(OP_WRITE)] = { -1, -1 },
[C(OP_PREFETCH)] = { -1, -1 },
},
[C(NODE)] = { /* RESULT_ACCESS RESULT_MISS */
[C(OP_READ)] = { -1, -1 },
[C(OP_WRITE)] = { -1, -1 },
[C(OP_PREFETCH)] = { -1, -1 },
},
};
static struct power_pmu power4_pmu = {
.name = "POWER4/4+",
.n_counter = 8,
.max_alternatives = 5,
.add_fields = 0x0000001100005555ul,
.test_adder = 0x0011083300000000ul,
.compute_mmcr = p4_compute_mmcr,
.get_constraint = p4_get_constraint,
.get_alternatives = p4_get_alternatives,
.disable_pmc = p4_disable_pmc,
.n_generic = ARRAY_SIZE(p4_generic_events),
.generic_events = p4_generic_events,
.cache_events = &power4_cache_events,
};
static int __init init_power4_pmu(void)
{
if (!cur_cpu_spec->oprofile_cpu_type ||
strcmp(cur_cpu_spec->oprofile_cpu_type, "ppc64/power4"))
return -ENODEV;
return register_power_pmu(&power4_pmu);
}
early_initcall(init_power4_pmu);