blob: 4f6cf932e6cfad04cb2dbb2c9b5483633240c6f5 [file] [log] [blame]
/*
* Copyright (c) 2015-2017, ARM Limited and Contributors. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <platform_def.h>
#include <arch.h>
#include <platform.h>
#include <lib/psci/psci.h>
#pragma weak plat_core_pos_by_mpidr
/*******************************************************************************
* This function implements a part of the critical interface between the psci
* generic layer and the platform that allows the former to query the platform
* to convert an MPIDR to a unique linear index. An error code (-1) is returned
* in case the MPIDR is invalid.
******************************************************************************/
int32_t plat_core_pos_by_mpidr(u_register_t mpidr)
{
u_register_t cluster_id, cpu_id;
int32_t result;
cluster_id = (mpidr >> (u_register_t)MPIDR_AFF1_SHIFT) & (u_register_t)MPIDR_AFFLVL_MASK;
cpu_id = (mpidr >> (u_register_t)MPIDR_AFF0_SHIFT) & (u_register_t)MPIDR_AFFLVL_MASK;
result = (int32_t)cpu_id + ((int32_t)cluster_id * 4);
if (cluster_id >= (u_register_t)PLATFORM_CLUSTER_COUNT) {
result = PSCI_E_NOT_PRESENT;
}
/*
* Validate cpu_id by checking whether it represents a CPU in
* one of the two clusters present on the platform.
*/
if (cpu_id >= (u_register_t)PLATFORM_MAX_CPUS_PER_CLUSTER) {
result = PSCI_E_NOT_PRESENT;
}
return result;
}