blob: b1409b95d242d1caf319196b2e28849980f668d8 [file] [log] [blame]
/*
* Copyright (c) 2021-2023, 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 <common/debug.h>
#include <lib/el3_runtime/context_mgmt.h>
#include <lib/extensions/sme.h>
#include <lib/extensions/sve.h>
void sme_enable(cpu_context_t *context)
{
u_register_t reg;
el3_state_t *state;
/* Get the context state. */
state = get_el3state_ctx(context);
/* Set the ENTP2 bit in SCR_EL3 to enable access to TPIDR2_EL0. */
reg = read_ctx_reg(state, CTX_SCR_EL3);
reg |= SCR_ENTP2_BIT;
write_ctx_reg(state, CTX_SCR_EL3, reg);
}
void sme_enable_per_world(per_world_context_t *per_world_ctx)
{
u_register_t reg;
/* Enable SME in CPTR_EL3. */
reg = per_world_ctx->ctx_cptr_el3;
reg |= ESM_BIT;
per_world_ctx->ctx_cptr_el3 = reg;
}
void sme_init_el3(void)
{
u_register_t cptr_el3 = read_cptr_el3();
u_register_t smcr_el3;
/* Set CPTR_EL3.ESM bit so we can access SMCR_EL3 without trapping. */
write_cptr_el3(cptr_el3 | ESM_BIT);
isb();
/*
* Set the max LEN value and FA64 bit. This register is set up per_world
* to be the least restrictive, then lower ELs can restrict as needed
* using SMCR_EL2 and SMCR_EL1.
*/
smcr_el3 = SMCR_ELX_LEN_MAX;
if (read_feat_sme_fa64_id_field() != 0U) {
VERBOSE("[SME] FA64 enabled\n");
smcr_el3 |= SMCR_ELX_FA64_BIT;
}
/*
* Enable access to ZT0 register.
* Make sure FEAT_SME2 is supported by the hardware before continuing.
* If supported, Set the EZT0 bit in SMCR_EL3 to allow instructions to
* access ZT0 register without trapping.
*/
if (is_feat_sme2_supported()) {
VERBOSE("SME2 enabled\n");
smcr_el3 |= SMCR_ELX_EZT0_BIT;
}
write_smcr_el3(smcr_el3);
/* Reset CPTR_EL3 value. */
write_cptr_el3(cptr_el3);
isb();
}
void sme_init_el2_unused(void)
{
/*
* CPTR_EL2.TCPAC: Set to zero so that Non-secure EL1 accesses to the
* CPACR_EL1 or CPACR from both Execution states do not trap to EL2.
*/
write_cptr_el2(read_cptr_el2() & ~CPTR_EL2_TCPAC_BIT);
}
void sme_disable(cpu_context_t *context)
{
u_register_t reg;
el3_state_t *state;
/* Get the context state. */
state = get_el3state_ctx(context);
/* Disable access to TPIDR2_EL0. */
reg = read_ctx_reg(state, CTX_SCR_EL3);
reg &= ~SCR_ENTP2_BIT;
write_ctx_reg(state, CTX_SCR_EL3, reg);
}
void sme_disable_per_world(per_world_context_t *per_world_ctx)
{
u_register_t reg;
/* Disable SME, SVE, and FPU since they all share registers. */
reg = per_world_ctx->ctx_cptr_el3;
reg &= ~ESM_BIT; /* Trap SME */
reg &= ~CPTR_EZ_BIT; /* Trap SVE */
reg |= TFP_BIT; /* Trap FPU/SIMD */
per_world_ctx->ctx_cptr_el3 = reg;
}