linux-stable/include/linux/coresight-pmu.h
James Clark 2d693ed436 coresight: Add config flag to enable branch broadcast
When enabled, all taken branch addresses are output, even if the branch
was because of a direct branch instruction. This enables reconstruction
of the program flow without having access to the memory image of the
code being executed.

Use bit 8 for the config option which would be the correct bit for
programming ETMv3. Although branch broadcast can't be enabled on ETMv3
because it's not in the define ETM3X_SUPPORTED_OPTIONS, using the
correct bit might help prevent future collisions or allow it to be
enabled if needed.

Signed-off-by: James Clark <james.clark@arm.com>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20220511144601.2257870-2-james.clark@arm.com
2022-07-06 16:32:08 +01:00

48 lines
1.4 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright(C) 2015 Linaro Limited. All rights reserved.
* Author: Mathieu Poirier <mathieu.poirier@linaro.org>
*/
#ifndef _LINUX_CORESIGHT_PMU_H
#define _LINUX_CORESIGHT_PMU_H
#define CORESIGHT_ETM_PMU_NAME "cs_etm"
#define CORESIGHT_ETM_PMU_SEED 0x10
/*
* Below are the definition of bit offsets for perf option, and works as
* arbitrary values for all ETM versions.
*
* Most of them are orignally from ETMv3.5/PTM's ETMCR config, therefore,
* ETMv3.5/PTM doesn't define ETMCR config bits with prefix "ETM3_" and
* directly use below macros as config bits.
*/
#define ETM_OPT_BRANCH_BROADCAST 8
#define ETM_OPT_CYCACC 12
#define ETM_OPT_CTXTID 14
#define ETM_OPT_CTXTID2 15
#define ETM_OPT_TS 28
#define ETM_OPT_RETSTK 29
/* ETMv4 CONFIGR programming bits for the ETM OPTs */
#define ETM4_CFG_BIT_BB 3
#define ETM4_CFG_BIT_CYCACC 4
#define ETM4_CFG_BIT_CTXTID 6
#define ETM4_CFG_BIT_VMID 7
#define ETM4_CFG_BIT_TS 11
#define ETM4_CFG_BIT_RETSTK 12
#define ETM4_CFG_BIT_VMID_OPT 15
static inline int coresight_get_trace_id(int cpu)
{
/*
* A trace ID of value 0 is invalid, so let's start at some
* random value that fits in 7 bits and go from there. Since
* the common convention is to have data trace IDs be I(N) + 1,
* set instruction trace IDs as a function of the CPU number.
*/
return (CORESIGHT_ETM_PMU_SEED + (cpu * 2));
}
#endif