blob: fe4205e7df0dcc430d21d1eb88ccd03f73411dfb [file] [log] [blame]
/*
* Copyright (c) 2023, Arm Limited. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <arch.h>
#include <arch_features.h>
#include <arch_helpers.h>
#include <lib/extensions/pmuv3.h>
static u_register_t mtpmu_disable_el3(u_register_t sdcr)
{
if (!is_feat_mtpmu_supported()) {
return sdcr;
}
/*
* SDCR.MTPME = 0
* FEAT_MTPMU is disabled. The Effective value of PMEVTYPER<n>.MT is
* zero.
*/
sdcr &= ~SDCR_MTPME_BIT;
return sdcr;
}
/*
* Applies to all PMU versions. Name is PMUv3 for compatibility with aarch64 and
* to not clash with platforms which reuse the PMU name
*/
void pmuv3_disable_el3(void)
{
u_register_t sdcr = read_sdcr();
/* ---------------------------------------------------------------------
* Initialise SDCR, setting all the fields rather than relying on hw.
*
* SDCR.SCCD: Set to one so that cycle counting by PMCCNTR is prohibited
* in Secure state. This bit is RES0 in versions of the architecture
* earlier than ARMv8.5
*
* SDCR.SPME: Set to zero so that event counting is prohibited in Secure
* state (and explicitly EL3 with later revisions). If ARMv8.2 Debug is
* not implemented this bit does not have any effect on the counters
* unless there is support for the implementation defined
* authentication interface ExternalSecureNoninvasiveDebugEnabled().
* ---------------------------------------------------------------------
*/
sdcr = (sdcr | SDCR_SCCD_BIT) & ~SDCR_SPME_BIT;
sdcr = mtpmu_disable_el3(sdcr);
write_sdcr(sdcr);
/* ---------------------------------------------------------------------
* Initialise PMCR, setting all fields rather than relying
* on hw. Some fields are architecturally UNKNOWN on reset.
*
* PMCR.DP: Set to one to prohibit cycle counting whilst in Secure mode.
*
* PMCR.X: Set to zero to disable export of events.
*
* PMCR.C: Set to one to reset PMCCNTR.
*
* PMCR.P: Set to one to reset each event counter PMEVCNTR<n> to zero.
*
* PMCR.E: Set to zero to disable cycle and event counters.
* ---------------------------------------------------------------------
*/
write_pmcr(read_pmcr() | PMCR_DP_BIT | PMCR_C_BIT | PMCR_P_BIT |
~(PMCR_X_BIT | PMCR_E_BIT));
}