path: root/tools/perf/util/intel-pt-decoder/intel-pt-pkt-decoder.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * intel_pt_pkt_decoder.c: Intel Processor Trace support
 * Copyright (c) 2013-2014, Intel Corporation.
 */

#include <stdio.h>
#include <string.h>
#include <endian.h>
#include <byteswap.h>
#include <linux/kernel.h>
#include <linux/compiler.h>
#include <linux/unaligned.h>

#include "intel-pt-pkt-decoder.h"

#define BIT(n)		(1 << (n))

#define BIT63		((uint64_t)1 << 63)

#if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
#define memcpy_le64(d, s, n) do { \
	memcpy((d), (s), (n));    \
	*(d) = le64_to_cpu(*(d)); \
} while (0)
#else
#define memcpy_le64 memcpy
#endif

static const char * const packet_name[] = {
	[INTEL_PT_BAD]		= "Bad Packet!",
	[INTEL_PT_PAD]		= "PAD",
	[INTEL_PT_TNT]		= "TNT",
	[INTEL_PT_TIP_PGD]	= "TIP.PGD",
	[INTEL_PT_TIP_PGE]	= "TIP.PGE",
	[INTEL_PT_TSC]		= "TSC",
	[INTEL_PT_TMA]		= "TMA",
	[INTEL_PT_MODE_EXEC]	= "MODE.Exec",
	[INTEL_PT_MODE_TSX]	= "MODE.TSX",
	[INTEL_PT_MTC]		= "MTC",
	[INTEL_PT_TIP]		= "TIP",
	[INTEL_PT_FUP]		= "FUP",
	[INTEL_PT_CYC]		= "CYC",
	[INTEL_PT_VMCS]		= "VMCS",
	[INTEL_PT_PSB]		= "PSB",
	[INTEL_PT_PSBEND]	= "PSBEND",
	[INTEL_PT_CBR]		= "CBR",
	[INTEL_PT_TRACESTOP]	= "TraceSTOP",
	[INTEL_PT_PIP]		= "PIP",
	[INTEL_PT_OVF]		= "OVF",
	[INTEL_PT_MNT]		= "MNT",
	[INTEL_PT_PTWRITE]	= "PTWRITE",
	[INTEL_PT_PTWRITE_IP]	= "PTWRITE",
	[INTEL_PT_EXSTOP]	= "EXSTOP",
	[INTEL_PT_EXSTOP_IP]	= "EXSTOP",
	[INTEL_PT_MWAIT]	= "MWAIT",
	[INTEL_PT_PWRE]		= "PWRE",
	[INTEL_PT_PWRX]		= "PWRX",
	[INTEL_PT_BBP]		= "BBP",
	[INTEL_PT_BIP]		= "BIP",
	[INTEL_PT_BEP]		= "BEP",
	[INTEL_PT_BEP_IP]	= "BEP",
	[INTEL_PT_CFE]		= "CFE",
	[INTEL_PT_CFE_IP]	= "CFE",
	[INTEL_PT_EVD]		= "EVD",
};

const char *intel_pt_pkt_name(enum intel_pt_pkt_type type)
{
	return packet_name[type];
}

static int intel_pt_get_long_tnt(const unsigned char *buf, size_t len,
				 struct intel_pt_pkt *packet)
{
	uint64_t payload;
	int count;

	if (len < 8)
		return INTEL_PT_NEED_MORE_BYTES;

	payload = get_unaligned_le64(buf);

	for (count = 47; count; count--) {
		if (payload & BIT63)
			break;
		payload <<= 1;
	}

	packet->type = INTEL_PT_TNT;
	packet->count = count;
	packet->payload = payload << 1;
	return 8;
}

static int intel_pt_get_pip(const unsigned char *buf, size_t len,
			    struct intel_pt_pkt *packet)
{
	uint64_t payload = 0;

	if (len < 8)
		return INTEL_PT_NEED_MORE_BYTES;

	packet->type = INTEL_PT_PIP;
	memcpy_le64(&payload, buf + 2, 6);
	packet->payload = payload;

	return 8;
}

static int intel_pt_get_tracestop(struct intel_pt_pkt *packet)
{
	packet->type = INTEL_PT_TRACESTOP;
	return 2;
}

static int intel_pt_get_cbr(const unsigned char *buf, size_t len,
			    struct intel_pt_pkt *packet)
{
	if (len < 4)
		return INTEL_PT_NEED_MORE_BYTES;
	packet->type = INTEL_PT_CBR;
	packet->payload = get_unaligned_le16(buf + 2);
	return 4;
}

static int intel_pt_get_vmcs(const unsigned char *buf, size_t len,
			     struct intel_pt_pkt *packet)
{
	if (len < 7)
		return INTEL_PT_NEED_MORE_BYTES;

	packet->type = INTEL_PT_VMCS;
	packet->count = 5;
	memcpy_le64(&packet->payload, buf + 2, 5);

	return 7;
}

static int intel_pt_get_ovf(struct intel_pt_pkt *packet)
{
	packet->type = INTEL_PT_OVF;
	return 2;
}

static int intel_pt_get_psb(const unsigned char *buf, size_t len,
			    struct intel_pt_pkt *packet)
{
	int i;

	if (len < 16)
		return INTEL_PT_NEED_MORE_BYTES;

	for (i = 2; i < 16; i += 2) {
		if (buf[i] != 2 || buf[i + 1] != 0x82)
			return INTEL_PT_BAD_PACKET;
	}

	packet->type = INTEL_PT_PSB;
	return 16;
}

static int intel_pt_get_psbend(struct intel_pt_pkt *packet)
{
	packet->type = INTEL_PT_PSBEND;
	return 2;
}

static int intel_pt_get_tma(const unsigned char *buf, size_t len,
			    struct intel_pt_pkt *packet)
{
	if (len < 7)
		return INTEL_PT_NEED_MORE_BYTES;

	packet->type = INTEL_PT_TMA;
	packet->payload = buf[2] | (buf[3]