plat/nvidia/tegra/common/tegra_topology.c

   1 /*
   2  * Copyright (c) 2015-2017, ARM Limited and Contributors. All rights reserved.
   3  *
   4  * SPDX-License-Identifier: BSD-3-Clause
   5  */
   6
   7 #include <platform_def.h>
   8
   9 #include <arch.h>
  10 #include <lib/psci/psci.h>
  11 #include <plat/common/platform.h>
  12
  13 #pragma weak plat_core_pos_by_mpidr
  14
  15 /*******************************************************************************
  16  * This function implements a part of the critical interface between the psci
  17  * generic layer and the platform that allows the former to query the platform
  18  * to convert an MPIDR to a unique linear index. An error code (-1) is returned
  19  * in case the MPIDR is invalid.
  20  ******************************************************************************/
  21 int32_t plat_core_pos_by_mpidr(u_register_t mpidr)
  22 {
  23         u_register_t cluster_id, cpu_id;
  24         int32_t result;
  25
  26         cluster_id = (mpidr >> (u_register_t)MPIDR_AFF1_SHIFT) &
  27                      (u_register_t)MPIDR_AFFLVL_MASK;
  28         cpu_id = (mpidr >> (u_register_t)MPIDR_AFF0_SHIFT) &
  29                  (u_register_t)MPIDR_AFFLVL_MASK;
  30
  31         /* CorePos = CoreId + (ClusterId * cpus per cluster) */
  32         result = (int32_t)cpu_id + ((int32_t)cluster_id *
  33                  PLATFORM_MAX_CPUS_PER_CLUSTER);
  34
  35         if (cluster_id >= (u_register_t)PLATFORM_CLUSTER_COUNT) {
  36                 result = PSCI_E_NOT_PRESENT;
  37         }
  38
  39         /*
  40          * Validate cpu_id by checking whether it represents a CPU in
  41          * one of the two clusters present on the platform.
  42          */
  43         if (cpu_id >= (u_register_t)PLATFORM_MAX_CPUS_PER_CLUSTER) {
  44                 result = PSCI_E_NOT_PRESENT;
  45         }
  46
  47         return result;
  48 }