arm-trusted-firmware/common/runtime_svc.c
Achin Gupta c8afc78919 psci: fix error due to a non zero context id
In the previous psci implementation, the psci_afflvl_power_on_finish()
function would run into an error condition if the value of the context
id parameter in the cpu_on and cpu_suspend psci calls was != 0. The
parameter was being restored as the return value of the affinity level
0 finisher function. A non zero context id would be treated as an
error condition. This would prevent successful wake up of the cpu from
a power down state. Also, the contents of the general purpose
registers were not being cleared upon return to the non-secure world
after a cpu power up. This could potentially allow the non-secure
world to view secure data.

This patch ensures that all general purpose registers are set to ~0
prior to the final eret that drops the execution to the non-secure
world. The context id is used to initialize the general purpose
register x0 prior to re-entry into the non-secure world and is no
longer restored as a function return value. A platform helper
(platform_get_stack()) has been introduced to facilitate this change.

Change-Id: I2454911ffd75705d6aa8609a5d250d9b26fa097c
2013-12-05 12:28:50 +00:00

51 lines
2.1 KiB
C

/*
* Copyright (c) 2013, ARM Limited and Contributors. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
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#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <assert.h>
#include <arch_helpers.h>
#include <console.h>
#include <platform.h>
#include <semihosting.h>
#include <bl_common.h>
#include <psci.h>
#include <runtime_svc.h>
/*******************************************************************************
* Perform initialization of runtime services possibly across exception levels
* in the secure address space e.g. psci & interrupt handling.
******************************************************************************/
void runtime_svc_init(unsigned long mpidr)
{
psci_setup(mpidr);
return;
}