Commit 742bd95b authored by Paul Mackerras's avatar Paul Mackerras
Browse files

perfcounters/powerpc: Add support for POWER5 processors 



This adds the back-end for the PMU on the POWER5 processor.  This knows
how to use the fixed-function PMC5 and PMC6 (instructions completed and
run cycles).  Unlike POWER6, PMC5/6 obey the freeze conditions and can
generate interrupts, so their use doesn't impose any extra restrictions.

POWER5+ is different and is not supported by this patch.

Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
parent d095cd46

arch/powerpc/kernel/Makefile

+2 −1
Original line number Diff line number Diff line
@@ -94,7 +94,8 @@ obj-$(CONFIG_AUDIT) += audit.o 
obj64-$(CONFIG_AUDIT)		+= compat_audit.o



obj-$(CONFIG_DYNAMIC_FTRACE)	+= ftrace.o

obj-$(CONFIG_PERF_COUNTERS)	+= perf_counter.o ppc970-pmu.o power6-pmu.o

obj-$(CONFIG_PERF_COUNTERS)	+= perf_counter.o ppc970-pmu.o power5-pmu.o \

				   power6-pmu.o



obj-$(CONFIG_8XX_MINIMAL_FPEMU) += softemu8xx.o

arch/powerpc/kernel/perf_counter.c

+4 −0
Original line number Diff line number Diff line
@@ -824,6 +824,7 @@ void hw_perf_counter_setup(int cpu) 
}



extern struct power_pmu ppc970_pmu;

extern struct power_pmu power5_pmu;

extern struct power_pmu power6_pmu;



static int init_perf_counters(void)
@@ -843,6 +844,9 @@ static int init_perf_counters(void) 
	case PV_970MP:

		ppmu = &ppc970_pmu;

		break;

	case PV_POWER5:

		ppmu = &power5_pmu;

		break;

	case 0x3e:

		ppmu = &power6_pmu;

		break;

arch/powerpc/kernel/power5-pmu.c

0 → 100644
+475 −0
Original line number Diff line number Diff line 
/*

 * Performance counter support for POWER5 (not POWER5++) 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_counter.h>

#include <asm/reg.h>



/*

 * Bits in event code for POWER5 (not POWER5++)

 */

#define PM_PMC_SH	20	/* PMC number (1-based) for direct events */

#define PM_PMC_MSK	0xf

#define PM_PMC_MSKS	(PM_PMC_MSK << PM_PMC_SH)

#define PM_UNIT_SH	16	/* TTMMUX number and setting - unit select */

#define PM_UNIT_MSK	0xf

#define PM_BYTE_SH	12	/* Byte number of event bus to use */

#define PM_BYTE_MSK	7

#define PM_GRS_SH	8	/* Storage subsystem mux select */

#define PM_GRS_MSK	7

#define PM_BUSEVENT_MSK	0x80	/* Set if event uses event bus */

#define PM_PMCSEL_MSK	0x7f



/* Values in PM_UNIT field */

#define PM_FPU		0

#define PM_ISU0		1

#define PM_IFU		2

#define PM_ISU1		3

#define PM_IDU		4

#define PM_ISU0_ALT	6

#define PM_GRS		7

#define PM_LSU0		8

#define PM_LSU1		0xc

#define PM_LASTUNIT	0xc



/*

 * Bits in MMCR1 for POWER5

 */

#define MMCR1_TTM0SEL_SH	62

#define MMCR1_TTM1SEL_SH	60

#define MMCR1_TTM2SEL_SH	58

#define MMCR1_TTM3SEL_SH	56

#define MMCR1_TTMSEL_MSK	3

#define MMCR1_TD_CP_DBG0SEL_SH	54

#define MMCR1_TD_CP_DBG1SEL_SH	52

#define MMCR1_TD_CP_DBG2SEL_SH	50

#define MMCR1_TD_CP_DBG3SEL_SH	48

#define MMCR1_GRS_L2SEL_SH	46

#define MMCR1_GRS_L2SEL_MSK	3

#define MMCR1_GRS_L3SEL_SH	44

#define MMCR1_GRS_L3SEL_MSK	3

#define MMCR1_GRS_MCSEL_SH	41

#define MMCR1_GRS_MCSEL_MSK	7

#define MMCR1_GRS_FABSEL_SH	39

#define MMCR1_GRS_FABSEL_MSK	3

#define MMCR1_PMC1_ADDER_SEL_SH	35

#define MMCR1_PMC2_ADDER_SEL_SH	34

#define MMCR1_PMC3_ADDER_SEL_SH	33

#define MMCR1_PMC4_ADDER_SEL_SH	32

#define MMCR1_PMC1SEL_SH	25

#define MMCR1_PMC2SEL_SH	17

#define MMCR1_PMC3SEL_SH	9

#define MMCR1_PMC4SEL_SH	1

#define MMCR1_PMCSEL_SH(n)	(MMCR1_PMC1SEL_SH - (n) * 8)

#define MMCR1_PMCSEL_MSK	0x7f



/*

 * Bits in MMCRA

 */



/*

 * Layout of constraint bits:

 * 6666555555555544444444443333333333222222222211111111110000000000

 * 3210987654321098765432109876543210987654321098765432109876543210

 *         <><>[  ><><>< ><> [  >[ >[ ><  ><  ><  ><  ><><><><><><>

 *         T0T1 NC G0G1G2 G3  UC PS1PS2 B0  B1  B2  B3 P6P5P4P3P2P1

 *

 * T0 - TTM0 constraint

 *     54-55: TTM0SEL value (0=FPU, 2=IFU, 3=ISU1) 0xc0_0000_0000_0000

 *

 * T1 - TTM1 constraint

 *     52-53: TTM1SEL value (0=IDU, 3=GRS) 0x30_0000_0000_0000

 *

 * NC - number of counters

 *     51: NC error 0x0008_0000_0000_0000

 *     48-50: number of events needing PMC1-4 0x0007_0000_0000_0000

 *

 * G0..G3 - GRS mux constraints

 *     46-47: GRS_L2SEL value

 *     44-45: GRS_L3SEL value

 *     41-44: GRS_MCSEL value

 *     39-40: GRS_FABSEL value

 *	Note that these match up with their bit positions in MMCR1

 *

 * UC - unit constraint: can't have all three of FPU|IFU|ISU1, ISU0, IDU|GRS

 *     37: UC3 error 0x20_0000_0000

 *     36: FPU|IFU|ISU1 events needed 0x10_0000_0000

 *     35: ISU0 events needed 0x08_0000_0000

 *     34: IDU|GRS events needed 0x04_0000_0000

 *

 * PS1

 *     33: PS1 error 0x2_0000_0000

 *     31-32: count of events needing PMC1/2 0x1_8000_0000

 *

 * PS2

 *     30: PS2 error 0x4000_0000

 *     28-29: count of events needing PMC3/4 0x3000_0000

 *

 * B0

 *     24-27: Byte 0 event source 0x0f00_0000

 *	      Encoding as for the event code

 *

 * B1, B2, B3

 *     20-23, 16-19, 12-15: Byte 1, 2, 3 event sources

 *

 * P1..P6

 *     0-11: Count of events needing PMC1..PMC6

 */



static const int grsel_shift[8] = {

	MMCR1_GRS_L2SEL_SH, MMCR1_GRS_L2SEL_SH, MMCR1_GRS_L2SEL_SH,

	MMCR1_GRS_L3SEL_SH, MMCR1_GRS_L3SEL_SH, MMCR1_GRS_L3SEL_SH,

	MMCR1_GRS_MCSEL_SH, MMCR1_GRS_FABSEL_SH

};



/* Masks and values for using events from the various units */

static u64 unit_cons[PM_LASTUNIT+1][2] = {

	[PM_FPU] =   { 0xc0002000000000ull, 0x00001000000000ull },

	[PM_ISU0] =  { 0x00002000000000ull, 0x00000800000000ull },

	[PM_ISU1] =  { 0xc0002000000000ull, 0xc0001000000000ull },

	[PM_IFU] =   { 0xc0002000000000ull, 0x80001000000000ull },

	[PM_IDU] =   { 0x30002000000000ull, 0x00000400000000ull },

	[PM_GRS] =   { 0x30002000000000ull, 0x30000400000000ull },

};



static int power5_get_constraint(unsigned int event, u64 *maskp, u64 *valp)

{

	int pmc, byte, unit, sh;

	int bit, fmask;

	u64 mask = 0, value = 0;

	int grp = -1;



	pmc = (event >> PM_PMC_SH) & PM_PMC_MSK;

	if (pmc) {

		if (pmc > 6)

			return -1;

		sh = (pmc - 1) * 2;

		mask |= 2 << sh;

		value |= 1 << sh;

		if (pmc <= 4)

			grp = (pmc - 1) >> 1;

		else if (event != 0x500009 && event != 0x600005)

			return -1;

	}

	if (event & PM_BUSEVENT_MSK) {

		unit = (event >> PM_UNIT_SH) & PM_UNIT_MSK;

		if (unit > PM_LASTUNIT)

			return -1;

		if (unit == PM_ISU0_ALT)

			unit = PM_ISU0;

		mask |= unit_cons[unit][0];

		value |= unit_cons[unit][1];

		byte = (event >> PM_BYTE_SH) & PM_BYTE_MSK;

		if (byte >= 4) {

			if (unit != PM_LSU1)

				return -1;

			/* Map LSU1 low word (bytes 4-7) to unit LSU1+1 */

			++unit;

			byte &= 3;

		}

		if (unit == PM_GRS) {

			bit = event & 7;

			fmask = (bit == 6)? 7: 3;

			sh = grsel_shift[bit];

			mask |= (u64)fmask << sh;

			value |= (u64)((event >> PM_GRS_SH) & fmask) << sh;

		}

		/*

		 * Bus events on bytes 0 and 2 can be counted

		 * on PMC1/2; bytes 1 and 3 on PMC3/4.

		 */

		if (!pmc)

			grp = byte & 1;

		/* Set byte lane select field */

		mask  |= 0xfULL << (24 - 4 * byte);

		value |= (u64)unit << (24 - 4 * byte);

	}

	if (grp == 0) {

		/* increment PMC1/2 field */

		mask  |= 0x200000000ull;

		value |= 0x080000000ull;

	} else if (grp == 1) {

		/* increment PMC3/4 field */

		mask  |= 0x40000000ull;

		value |= 0x10000000ull;

	}

	if (pmc < 5) {

		/* need a counter from PMC1-4 set */

		mask  |= 0x8000000000000ull;

		value |= 0x1000000000000ull;

	}

	*maskp = mask;

	*valp = value;

	return 0;

}



#define MAX_ALT	3	/* at most 3 alternatives for any event */



static const unsigned int event_alternatives[][MAX_ALT] = {

	{ 0x120e4,  0x400002 },			/* PM_GRP_DISP_REJECT */

	{ 0x410c7,  0x441084 },			/* PM_THRD_L2MISS_BOTH_CYC */

	{ 0x100005, 0x600005 },			/* PM_RUN_CYC */

	{ 0x100009, 0x200009, 0x500009 },	/* PM_INST_CMPL */

	{ 0x300009, 0x400009 },			/* PM_INST_DISP */

};



/*

 * Scan the alternatives table for a match and return the

 * index into the alternatives table if found, else -1.

 */

static int find_alternative(unsigned int event)

{

	int i, j;



	for (i = 0; i < ARRAY_SIZE(event_alternatives); ++i) {

		if (event < event_alternatives[i][0])

			break;

		for (j = 0; j < MAX_ALT && event_alternatives[i][j]; ++j)

			if (event == event_alternatives[i][j])

				return i;

	}

	return -1;

}



static const unsigned char bytedecode_alternatives[4][4] = {

	/* PMC 1 */	{ 0x21, 0x23, 0x25, 0x27 },

	/* PMC 2 */	{ 0x07, 0x17, 0x0e, 0x1e },

	/* PMC 3 */	{ 0x20, 0x22, 0x24, 0x26 },

	/* PMC 4 */	{ 0x07, 0x17, 0x0e, 0x1e }

};



/*

 * Some direct events for decodes of event bus byte 3 have alternative

 * PMCSEL values on other counters.  This returns the alternative

 * event code for those that do, or -1 otherwise.

 */

static int find_alternative_bdecode(unsigned int event)

{

	int pmc, altpmc, pp, j;



	pmc = (event >> PM_PMC_SH) & PM_PMC_MSK;

	if (pmc == 0 || pmc > 4)

		return -1;

	altpmc = 5 - pmc;	/* 1 <-> 4, 2 <-> 3 */

	pp = event & PM_PMCSEL_MSK;

	for (j = 0; j < 4; ++j) {

		if (bytedecode_alternatives[pmc - 1][j] == pp) {

			return (event & ~(PM_PMC_MSKS | PM_PMCSEL_MSK)) |

				(altpmc << PM_PMC_SH) |

				bytedecode_alternatives[altpmc - 1][j];

		}

	}

	return -1;

}



static int power5_get_alternatives(unsigned int event, unsigned int alt[])

{

	int i, j, ae, nalt = 1;



	alt[0] = event;

	nalt = 1;

	i = find_alternative(event);

	if (i >= 0) {

		for (j = 0; j < MAX_ALT; ++j) {

			ae = event_alternatives[i][j];

			if (ae && ae != event)

				alt[nalt++] = ae;

		}

	} else {

		ae = find_alternative_bdecode(event);

		if (ae > 0)

			alt[nalt++] = ae;

	}

	return nalt;

}



static int power5_compute_mmcr(unsigned int event[], int n_ev,

			       unsigned int hwc[], u64 mmcr[])

{

	u64 mmcr1 = 0;

	unsigned int pmc, unit, byte, psel;

	unsigned int ttm, grp;

	int i, isbus, bit, grsel;

	unsigned int pmc_inuse = 0;

	unsigned int pmc_grp_use[2];

	unsigned char busbyte[4];

	unsigned char unituse[16];

	int ttmuse;



	if (n_ev > 6)

		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 > 6)

				return -1;

			if (pmc_inuse & (1 << (pmc - 1)))

				return -1;

			pmc_inuse |= 1 << (pmc - 1);

			/* count 1/2 vs 3/4 use */

			if (pmc <= 4)

				++pmc_grp_use[(pmc - 1) >> 1];

		}

		if (event[i] & PM_BUSEVENT_MSK) {

			unit = (event[i] >> PM_UNIT_SH) & PM_UNIT_MSK;

			byte = (event[i] >> PM_BYTE_SH) & PM_BYTE_MSK;

			if (unit > PM_LASTUNIT)

				return -1;

			if (unit == PM_ISU0_ALT)

				unit = PM_ISU0;

			if (byte >= 4) {

				if (unit != PM_LSU1)

					return -1;

				++unit;

				byte &= 3;

			}

			if (!pmc)

				++pmc_grp_use[byte & 1];

			if (busbyte[byte] && busbyte[byte] != unit)

				return -1;

			busbyte[byte] = unit;

			unituse[unit] = 1;

		}

	}

	if (pmc_grp_use[0] > 2 || pmc_grp_use[1] > 2)

		return -1;



	/*

	 * Assign resources and set multiplexer selects.

	 *

	 * PM_ISU0 can go either on TTM0 or TTM1, but that's the only

	 * choice we have to deal with.

	 */

	if (unituse[PM_ISU0] &

	    (unituse[PM_FPU] | unituse[PM_IFU] | unituse[PM_ISU1])) {

		unituse[PM_ISU0_ALT] = 1;	/* move ISU to TTM1 */

		unituse[PM_ISU0] = 0;

	}

	/* Set TTM[01]SEL fields. */

	ttmuse = 0;

	for (i = PM_FPU; i <= PM_ISU1; ++i) {

		if (!unituse[i])

			continue;

		if (ttmuse++)

			return -1;

		mmcr1 |= (u64)i << MMCR1_TTM0SEL_SH;

	}

	ttmuse = 0;

	for (; i <= PM_GRS; ++i) {

		if (!unituse[i])

			continue;

		if (ttmuse++)

			return -1;

		mmcr1 |= (u64)(i & 3) << MMCR1_TTM1SEL_SH;

	}

	if (ttmuse > 1)

		return -1;



	/* Set byte lane select fields, TTM[23]SEL and GRS_*SEL. */

	for (byte = 0; byte < 4; ++byte) {

		unit = busbyte[byte];

		if (!unit)

			continue;

		if (unit == PM_ISU0 && unituse[PM_ISU0_ALT]) {

			/* get ISU0 through TTM1 rather than TTM0 */

			unit = PM_ISU0_ALT;

		} else if (unit == PM_LSU1 + 1) {

			/* select lower word of LSU1 for this byte */

			mmcr1 |= 1ull << (MMCR1_TTM3SEL_SH + 3 - byte);

		}

		ttm = unit >> 2;

		mmcr1 |= (u64)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;

		isbus = event[i] & PM_BUSEVENT_MSK;

		if (!pmc) {

			/* Bus event or any-PMC direct event */

			for (pmc = 0; pmc < 4; ++pmc) {

				if (pmc_inuse & (1 << pmc))

					continue;

				grp = (pmc >> 1) & 1;

				if (isbus) {

					if (grp == (byte & 1))

						break;

				} else if (pmc_grp_use[grp] < 2) {

					++pmc_grp_use[grp];

					break;

				}

			}

			pmc_inuse |= 1 << pmc;

		} else if (pmc <= 4) {

			/* Direct event */

			--pmc;

			if ((psel == 8 || psel == 0x10) && isbus && (byte & 2))

				/* add events on higher-numbered bus */

				mmcr1 |= 1ull << (MMCR1_PMC1_ADDER_SEL_SH - pmc);

		} else {

			/* Instructions or run cycles on PMC5/6 */

			--pmc;

		}

		if (isbus && unit == PM_GRS) {

			bit = psel & 7;

			grsel = (event[i] >> PM_GRS_SH) & PM_GRS_MSK;

			mmcr1 |= (u64)grsel << grsel_shift[bit];

		}

		if (pmc <= 3)

			mmcr1 |= psel << MMCR1_PMCSEL_SH(pmc);

		hwc[i] = pmc;

	}



	/* Return MMCRx values */

	mmcr[0] = 0;

	if (pmc_inuse & 1)

		mmcr[0] = MMCR0_PMC1CE;

	if (pmc_inuse & 0x3e)

		mmcr[0] |= MMCR0_PMCjCE;

	mmcr[1] = mmcr1;

	mmcr[2] = 0;

	return 0;

}



static void power5_disable_pmc(unsigned int pmc, u64 mmcr[])

{

	if (pmc <= 3)

		mmcr[1] &= ~(0x7fUL << MMCR1_PMCSEL_SH(pmc));

}



static int power5_generic_events[] = {

	[PERF_COUNT_CPU_CYCLES] = 0xf,

	[PERF_COUNT_INSTRUCTIONS] = 0x100009,

	[PERF_COUNT_CACHE_REFERENCES] = 0x4c1090,	/* LD_REF_L1 */

	[PERF_COUNT_CACHE_MISSES] = 0x3c1088,		/* LD_MISS_L1 */

	[PERF_COUNT_BRANCH_INSTRUCTIONS] = 0x230e4,	/* BR_ISSUED */ 

	[PERF_COUNT_BRANCH_MISSES] = 0x230e5,		/* BR_MPRED_CR */

};



struct power_pmu power5_pmu = {

	.n_counter = 6,

	.max_alternatives = MAX_ALT,

	.add_fields = 0x7000090000555ull,

	.test_adder = 0x3000490000000ull,

	.compute_mmcr = power5_compute_mmcr,

	.get_constraint = power5_get_constraint,

	.get_alternatives = power5_get_alternatives,

	.disable_pmc = power5_disable_pmc,

	.n_generic = ARRAY_SIZE(power5_generic_events),

	.generic_events = power5_generic_events,

};

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