arm-trusted-firmware/lib/extensions/spe/spe.c
Boyan Karatotev 60d330dc4d refactor(cpufeat): separate the EL2 and EL3 enablement code
Combining the EL2 and EL3 enablement code necessitates that it must be
called at el3_exit, which is the only place with enough context to make
the decision of what needs to be set.
Decouple them to allow them to be called from elsewhere.

Signed-off-by: Boyan Karatotev <boyan.karatotev@arm.com>
Change-Id: I147764c42771e7d4100699ec8fae98dac0a505c0
2023-07-04 14:57:46 +01:00

88 lines
1.9 KiB
C

/*
* Copyright (c) 2017-2023, Arm Limited and Contributors. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <stdbool.h>
#include <arch.h>
#include <arch_features.h>
#include <arch_helpers.h>
#include <lib/el3_runtime/pubsub.h>
#include <lib/extensions/spe.h>
static inline void psb_csync(void)
{
/*
* The assembler does not yet understand the psb csync mnemonic
* so use the equivalent hint instruction.
*/
__asm__ volatile("hint #17");
}
void spe_init_el3(void)
{
uint64_t v;
/*
* MDCR_EL2.NSPB (ARM v8.2): SPE enabled in Non-secure state
* and disabled in secure state. Accesses to SPE registers at
* S-EL1 generate trap exceptions to EL3.
*
* MDCR_EL3.EnPMSN (ARM v8.7): Do not trap access to PMSNEVFR_EL1
* register at NS-EL1 or NS-EL2 to EL3 if FEAT_SPEv1p2 is implemented.
* Setting this bit to 1 doesn't have any effect on it when
* FEAT_SPEv1p2 not implemented.
*/
v = read_mdcr_el3();
v |= MDCR_NSPB(MDCR_NSPB_EL1) | MDCR_EnPMSN_BIT;
write_mdcr_el3(v);
}
void spe_init_el2_unused(void)
{
uint64_t v;
/*
* MDCR_EL2.TPMS (ARM v8.2): Do not trap statistical
* profiling controls to EL2.
*
* MDCR_EL2.E2PB (ARM v8.2): SPE enabled in Non-secure
* state. Accesses to profiling buffer controls at
* Non-secure EL1 are not trapped to EL2.
*/
v = read_mdcr_el2();
v &= ~MDCR_EL2_TPMS;
v |= MDCR_EL2_E2PB(MDCR_EL2_E2PB_EL1);
write_mdcr_el2(v);
}
void spe_disable(void)
{
uint64_t v;
/* Drain buffered data */
psb_csync();
dsbnsh();
/* Disable profiling buffer */
v = read_pmblimitr_el1();
v &= ~(1ULL << 0);
write_pmblimitr_el1(v);
isb();
}
static void *spe_drain_buffers_hook(const void *arg)
{
if (!is_feat_spe_supported())
return (void *)-1;
/* Drain buffered data */
psb_csync();
dsbnsh();
return (void *)0;
}
SUBSCRIBE_TO_EVENT(cm_entering_secure_world, spe_drain_buffers_hook);