/*
 * Performance counter support for PPC970-family processors.
 *
 * Copyright 2008-2009 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/string.h>
#include <linux/perf_counter.h>
#include <asm/reg.h>

/*
 * Bits in event code for PPC970
 */
#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_BYTE_SH	4	/* Byte number of event bus to use */
#define PM_BYTE_MSK	3
#define PM_PMCSEL_MSK	0xf

/* Values in PM_UNIT field */
#define PM_NONE		0
#define PM_FPU		1
#define PM_VPU		2
#define PM_ISU		3
#define PM_IFU		4
#define PM_IDU		5
#define PM_STS		6
#define PM_LSU0		7
#define PM_LSU1U	8
#define PM_LSU1L	9
#define PM_LASTUNIT	9

/*
 * Bits in MMCR0 for PPC970
 */
#define MMCR0_PMC1SEL_SH	8
#define MMCR0_PMC2SEL_SH	1
#define MMCR_PMCSEL_MSK		0x1f

/*
 * Bits in MMCR1 for PPC970
 */
#define MMCR1_TTM0SEL_SH	62
#define MMCR1_TTM1SEL_SH	59
#define MMCR1_TTM3SEL_SH	53
#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_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

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
 */

/*
 * Layout of constraint bits:
 * 6666555555555544444444443333333333222222222211111111110000000000
 * 3210987654321098765432109876543210987654321098765432109876543210
 *                 <><>[  >[  >[  ><  ><  ><  ><  ><><><><><><><><>
 *                 T0T1 UC  PS1 PS2 B0  B1  B2  B3 P1P2P3P4P5P6P7P8
 *
 * T0 - TTM0 constraint
 *     46-47: TTM0SEL value (0=FPU, 2=IFU, 3=VPU) 0xC000_0000_0000
 *
 * T1 - TTM1 constraint
 *     44-45: TTM1SEL value (0=IDU, 3=STS) 0x3000_0000_0000
 *
 * UC - unit constraint: can't have all three of FPU|IFU|VPU, ISU, IDU|STS
 *     43: UC3 error 0x0800_0000_0000
 *     42: FPU|IFU|VPU events needed 0x0400_0000_0000
 *     41: ISU events needed 0x0200_0000_0000
 *     40: IDU|STS 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
 *	      Encoding as for the event code
 *
 * B1, B2, B3
 *     24-27, 20-23, 16-19: Byte 1, 2, 3 event sources
 *
 * P1
 *     15: P1 error 0x8000
 *     14-15: Count of events needing PMC1
 *
 * P2..P8
 *     0-13: Count of events needing PMC2..PMC8
 */

/* Masks and values for using events from the various units */
static u64 unit_cons[PM_LASTUNIT+1][2] = {
	[PM_FPU] =   { 0xc80000000000ull, 0x040000000000ull },
	[PM_VPU] =   { 0xc80000000000ull, 0xc40000000000ull },
	[PM_ISU] =   { 0x080000000000ull, 0x020000000000ull },
	[PM_IFU] =   { 0xc80000000000ull, 0x840000000000ull },
	[PM_IDU] =   { 0x380000000000ull, 0x010000000000ull },
	[PM_STS] =   { 0x380000000000ull, 0x310000000000ull },
};

static int p970_get_constraint(unsigned int event, u64 *maskp, u64 *valp)
{
	int pmc, byte, unit, sh;
	u64 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;
	if (unit) {
		if (unit > PM_LASTUNIT)
			return -1;
		mask |= unit_cons[unit][0];
		value |= unit_cons[unit][1];
		byte = (event >> PM_BYTE_SH) & PM_BYTE_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;
		/* Set byte lane select field */
		mask  |= 0xfULL << (28 - 4 * byte);
		value |= (u64)unit << (28 - 4 * byte);
	}
	if (grp == 0) {
		/* increment PMC1/2/5/6 field */
		mask  |= 0x8000000000ull;
		value |= 0x1000000000ull;
	} else if (grp == 1) {
		/* increment PMC3/4/7/8 field */
		mask  |= 0x800000000ull;
		value |= 0x100000000ull;
	}
	*maskp = mask;
	*valp = value;
	return 0;
}

static int p970_get_alternatives(unsigned int event, unsigned int alt[])
{
	alt[0] = event;

	/* 2 alternatives for LSU empty */
	if (event == 0x2002 || event == 0x3002) {
		alt[1] = event ^ 0x1000;
		return 2;
	}
		
	return 1;
}

static int p970_compute_mmcr(unsigned int event[], int n_ev,
			     unsigned int hwc[], u64 mmcr[])
{
	u64 mmcr0 = 0, mmcr1 = 0, mmcra = 0;
	unsigned int pmc, unit, byte, psel;
	unsigned int ttm, grp;
	unsigned int pmc_inuse = 0;
	unsigned int pmc_grp_use[2];
	unsigned char busbyte[4];
	unsigned char unituse[16];
	unsigned char unitmap[] = { 0, 0<<3, 3<<3, 1<<3, 2<<3, 0|4, 3|4 };
	unsigned char ttmuse[2];
	unsigned char pmcsel[8];
	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;
		if (unit) {
			if (unit > PM_LASTUNIT)
				return -1;
			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] > 4 || pmc_grp_use[1] > 4)
		return -1;

	/*
	 * Assign resources and set multiplexer selects.
	 *
	 * PM_ISU can go either on TTM0 or TTM1, but that's the only
	 * choice we have to deal with.
	 */
	if (unituse[PM_ISU] &
	    (unituse[PM_FPU] | unituse[PM_IFU] | unituse[PM_VPU]))
		unitmap[PM_ISU] = 2 | 4;	/* move ISU to TTM1 */
	/* Set TTM[01]SEL fields. */
	ttmuse[0] = ttmuse[1] = 0;
	for (i = PM_FPU; i <= PM_STS; ++i) {
		if (!unituse[i])
			continue;
		ttm = unitmap[i];
		++ttmuse[(ttm >> 2) & 1];
		mmcr1 |= (u64)(ttm & ~4) << MMCR1_TTM1SEL_SH;
	}
	/* Check only one unit per TTMx */
	if (ttmuse[0] > 1 || ttmuse[1] > 1)
		return -1;

	/* Set byte lane select fields and TTM3SEL. */
	for (byte = 0; byte < 4; ++byte) {
		unit = busbyte[byte];
		if (!unit)
			continue;
		if (unit <= PM_STS)
			ttm = (unitmap[unit] >> 2) & 1;
		else if (unit == PM_LSU0)
			ttm = 2;
		else {
			ttm = 3;
			if (unit == PM_LSU1L && byte >= 2)
				mmcr1 |= 1ull << (MMCR1_TTM3SEL_SH + 3 - byte);
		}
		mmcr1 |= (u64)ttm << (MMCR1_TD_CP_DBG0SEL_SH - 2 * byte);
	}

	/* Second pass: assign PMCs, set PMCxSEL and PMCx_ADDER_SEL fields */
	memset(pmcsel, 0x8, sizeof(pmcsel));	/* 8 means don't count */
	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 any-PMC direct event */
			if (unit)
				psel |= 0x10 | ((byte & 2) << 2);
			else
				psel |= 8;
			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];
		}
		pmcsel[pmc] = psel;
		hwc[i] = pmc;
	}
	for (pmc = 0; pmc < 2; ++pmc)
		mmcr0 |= pmcsel[pmc] << (MMCR0_PMC1SEL_SH - 7 * pmc);
	for (; pmc < 8; ++pmc)
		mmcr1 |= (u64)pmcsel[pmc] << (MMCR1_PMC3SEL_SH - 5 * (pmc - 2));
	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 p970_disable_pmc(unsigned int pmc, u64 mmcr[])
{
	int shift, i;

	if (pmc <= 1) {
		shift = MMCR0_PMC1SEL_SH - 7 * pmc;
		i = 0;
	} else {
		shift = MMCR1_PMC3SEL_SH - 5 * (pmc - 2);
		i = 1;
	}
	/*
	 * Setting the PMCxSEL field to 0x08 disables PMC x.
	 */
	mmcr[i] = (mmcr[i] & ~(0x1fUL << shift)) | (0x08UL << shift);
}

static int ppc970_generic_events[] = {
	[PERF_COUNT_CPU_CYCLES] = 7,
	[PERF_COUNT_INSTRUCTIONS] = 1,
	[PERF_COUNT_CACHE_REFERENCES] = 0x8810,		/* PM_LD_REF_L1 */
	[PERF_COUNT_CACHE_MISSES] = 0x3810,		/* PM_LD_MISS_L1 */
	[PERF_COUNT_BRANCH_INSTRUCTIONS] = 0x431,	/* PM_BR_ISSUED */
	[PERF_COUNT_BRANCH_MISSES] = 0x327,		/* PM_GRP_BR_MPRED */
};

struct power_pmu ppc970_pmu = {
	.n_counter = 8,
	.max_alternatives = 2,
	.add_fields = 0x001100005555ull,
	.test_adder = 0x013300000000ull,
	.compute_mmcr = p970_compute_mmcr,
	.get_constraint = p970_get_constraint,
	.get_alternatives = p970_get_alternatives,
	.disable_pmc = p970_disable_pmc,
	.n_generic = ARRAY_SIZE(ppc970_generic_events),
	.generic_events = ppc970_generic_events,
};