clear wakeup enable bit upon resuming from suspend

The FVP specific code that gets called after a cpu has been physically
powered on after having been turned off or suspended earlier does not
clear the PWRC.PWKUPR.WEN bit. Not doing so causes problems if: a cpu
is suspended, woken from suspend, powered down through a cpu_off call
& receives a spurious interrupt. Since the WEN bit is not cleared
after the cpu woke up from suspend, the spurious wakeup will power the
cpu on. Since the cpu_off call clears the jump address in the mailbox
this spurious wakeup will cause the cpu to crash.

This patch fixes this issue by clearing the WEN bit whenever a cpu is
powered up.

Change-Id: Ic91f5dffe1ed01d76bc7fc807acf0ecd3e38ce5b
4 files changed
tree: ceb879d87b15ea26d705d87f3a4fdf06e00cb6e5
  1. arch/
  2. bl1/
  3. bl2/
  4. bl31/
  5. common/
  6. docs/
  7. drivers/
  8. fdts/
  9. include/
  10. lib/
  11. plat/
  12. acknowledgements.md
  13. contributing.md
  14. license.md
  15. Makefile
  16. readme.md
readme.md

ARM Trusted Firmware - version 0.2

ARM Trusted Firmware provides a reference implementation of secure world software for ARMv8-A, including Exception Level 3 (EL3) software. This first release focuses on support for ARM's [Fixed Virtual Platforms (FVPs)] FVP.

The intent is to provide a reference implementation of various ARM interface standards, such as the Power State Coordination Interface (PSCI), Trusted Board Boot Requirements (TBBR) and [Secure Monitor] TEE-SMC code. As far as possible the code is designed for reuse or porting to other ARMv8-A model and hardware platforms.

This release is the first one as source code: an initial prototype release was available in binary form in the [Linaro AArch64 OpenEmbedded Engineering Build] AArch64 LEB to support the new FVP Base platform models from ARM.

ARM will continue development in collaboration with interested parties to provide a full reference implementation of PSCI, TBBR and Secure Monitor code to the benefit of all developers working with ARMv8-A TrustZone software.

License

The software is provided under a BSD 3-Clause license. Certain source files are derived from FreeBSD code: the original license is included in these source files.

This Release

This software is an early implementation of the Trusted Firmware. Only limited functionality is provided at present and it has not been optimized or subjected to extended robustness or stress testing.

Functionality

  • Initial implementation of a subset of the Trusted Board Boot Requirements Platform Design Document (PDD).

  • Initializes the secure world (for example, exception vectors, control registers, GIC and interrupts for the platform), before transitioning into the normal world.

  • Supports both GICv2 and GICv3 initialization for use by normal world software.

  • Starts the normal world at the highest available Exception Level: EL2 if available, otherwise EL1.

  • Handles SMCs (Secure Monitor Calls) conforming to the [SMC Calling Convention PDD] SMCCC.

  • Handles SMCs relating to the [Power State Coordination Interface PDD] PSCI for the Secondary CPU Boot and CPU hotplug use-cases.

For a full list of updated functionality and implementation details, please see the User Guide. The Change Log provides details of changes made since the last release.

Platforms

This release of the Trusted Firmware has been tested on the following ARM FVPs (64-bit versions only):

  • FVP_Base_AEMv8A-AEMv8A (Version 5.1, Build 0.8.5108).
  • FVP_Base_Cortex-A57x4-A53x4 (Version 5.1, Build 0.8.5108).
  • FVP_Base_Cortex-A57x1-A53x1 (Version 5.1, Build 0.8.5108).

These models can be licensed from ARM: see [www.arm.com/fvp] FVP.

For an updated list of supported platforms, please see the Change Log.

Still to Come

  • Complete implementation of the PSCI specification.

  • Secure memory, Secure monitor, Test Secure OS & Secure interrupts.

  • Booting the firmware from a block device.

  • Completing the currently experimental GICv3 support.

For a full list of detailed issues in the current code, please see the Change Log.

Getting Started

Get the Trusted Firmware source code from GitHub.

See the User Guide for instructions on how to install, build and use the Trusted Firmware with the ARM FVPs.

See the Porting Guide as well for information about how to use this software on another ARMv8-A platform.

See the Contributing Guidelines for information on how to contribute to this project and the Acknowledgements file for a list of contributors to the project.

Feedback and support

ARM welcomes any feedback on the Trusted Firmware. Please send feedback using the GitHub issue tracker.

ARM licensees may contact ARM directly via their partner managers.


Copyright (c) 2013, ARM Limited and Contributors. All rights reserved.