Fix few typos in comments.
Cc: Achin Gupta <achin.gupta@arm.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Supreeth Venkatesh <supreeth.venkatesh@arm.com>
Signed-off-by: Antoine Coeur <coeur@gmx.fr>
Reviewed-by: Philippe Mathieu-Daude <philmd@redhat.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Signed-off-by: Philippe Mathieu-Daude <philmd@redhat.com>
Message-Id: <20200207010831.9046-76-philmd@redhat.com>
An extra 's' slipped into the FvIsBeingProcessed function
name. Drop it to fix the typo.
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Signed-off-by: Philippe Mathieu-Daude <philmd@redhat.com>
The FvHasBeenProcessed() and FvIsBeingProcesssed() functions make sure
that every firmware volume is processed only once (every driver in every
firmware volume should be discovered only once). For this, the functions
use a linked list.
In MdeModulePkg's DXE Core and SMM Core, the key used for identifying
those firmware volumes that have been processed is the EFI_HANDLE on which
the DXE or SMM firmware volume protocol is installed. In the
StandaloneMmPkg core however, the key is the address of the firmware
volume header; that is, it has type (EFI_FIRMWARE_VOLUME_HEADER*).
(EFI_FIRMWARE_VOLUME_HEADER*) has nothing to do with EFI_HANDLE.
EFI_HANDLE just happens to be specified as (VOID*), and therefore the
conversion between (EFI_FIRMWARE_VOLUME_HEADER*) and EFI_HANDLE is silent.
(The FvHasBeenProcessed() and FvIsBeingProcesssed() functions were likely
copied verbatim from MdeModulePkg's DXE Core and/or the SMM Core, and not
flagged by the compiler in StandaloneMmPkg due to UEFI regrettably
specifying EFI_HANDLE as (VOID*), thereby enabling the above implicit
conversion.)
We should not exploit this circumstance. Represent the key type faithfully
instead.
This is a semantic fix; there is no change in operation.
Cc: Achin Gupta <achin.gupta@arm.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Supreeth Venkatesh <supreeth.venkatesh@arm.com>
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jiewen Yao <Jiewen.yao@intel.com>
Reviewed-by: Achin Gupta <achin.gupta@arm.com>
Standalone MM requires 4 KB section alignment for all images, so that
strict permissions can be applied. Unfortunately, this results in a
lot of wasted space, which is usually costly in the secure world
environment that standalone MM is expected to operate in.
So let's permit the standalone MM drivers (but not the core) to be
delivered in a compressed firmware volume.
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: "Yao, Jiewen" <jiewen.yao@intel.com>
Reviewed-by: Achin Gupta <achin.gupta@arm.com>
Management Mode (MM) is a generic term used to describe a secure
execution environment provided by the CPU and related silicon that is
entered when the CPU detects a MMI. For x86 systems, this can be
implemented with System Management Mode (SMM). For ARM systems, this can
be implemented with TrustZone (TZ).
A MMI can be a CPU instruction or interrupt. Upon detection of a MMI, a
CPU will jump to the MM Entry Point and save some portion of its state
(the "save state") such that execution can be resumed.
The MMI can be generated synchronously by software or asynchronously by
a hardware event. Each MMI source can be detected, cleared and disabled.
Some systems provide for special memory (Management Mode RAM or MMRAM)
which is set aside for software running in MM. Usually the MMRAM is
hidden during normal CPU execution, but this is not required. Usually,
after MMRAM is hidden it cannot be exposed until the next system reset.
The MM Core Interface Specification describes three pieces of the PI
Management Mode architecture:
1. MM Dispatch
During DXE, the DXE Foundation works with the MM Foundation to
schedule MM drivers for execution in the discovered firmware volumes.
2. MM Initialization
MM related code opens MMRAM, creates the MMRAM memory map, and
launches the MM Foundation, which provides the necessary services to
launch MM-related drivers. Then, sometime before boot, MMRAM is
closed and locked. This piece may be completed during the
SEC, PEI or DXE phases.
3. MMI Management
When an MMI generated, the MM environment is created and then the MMI
sources are detected and MMI handlers called.
This patch implements the MM Core.
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Sughosh Ganu <sughosh.ganu@arm.com>
Signed-off-by: Supreeth Venkatesh <supreeth.venkatesh@arm.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Sami Mujawar
Antoine Coeur
Philippe Mathieu-Daude
Laszlo Ersek
Michael D Kinney
Ard Biesheuvel
Supreeth Venkatesh