Re: [PATCH v1 0/3] *** EFI_MM_COMMUNICATION_PROTOCOL ***

[Achin Gupta <achin.gupta@arm.com>]

On Thu, Oct 12, 2017 at 12:43:13PM -0500, Supreeth Venkatesh wrote:
> On Thu, 2017-10-12 at 18:38 +0100, Achin Gupta wrote:
> > Hi Supreeth,
> >
> > Could you acknowledge me as a contributor in the relevant patches and
> > repost?
> Can sure do as done in previous patches. However, Since I wanted you to
> review as well the latest changes, I was not sure whether co-author can
> be reviewer as well. I can add you as co-author in the next patchset,
> if that is what you prefer.

Yes I would prefer that!

Thanks!
Achin

>   
> >
> > cheers,
> > Achin
> >
> > On Thu, Oct 12, 2017 at 06:13:49PM +0100, Supreeth Venkatesh wrote:
> > >
> > > ***
> > > PI v1.5 Specification Volume 4 defines Management Mode Core
> > > Interface
> > > and defines EFI_MM_COMMUNICATION_PROTOCOL. This protocol provides a
> > > means of communicating between drivers outside of MM and MMI
> > > handlers inside of MM.
> > >
> > > EFI_MM_COMMUNICATION_PROTOCOL
> > > Summary
> > >   This protocol provides a means of communicating between drivers
> > > outside of MM and MMI
> > >   handlers inside of MM.
> > >
> > > GUID
> > >   #define EFI_MM_COMMUNICATION_PROTOCOL_GUID \
> > >   { 0xc68ed8e2, 0x9dc6, 0x4cbd, 0x9d, 0x94, 0xdb, 0x65, 0xac, 0xc5,
> > > 0xc3, 0x32 }
> > >
> > > Prototype
> > >   typedef struct _EFI_MM_COMMUNICATION_PROTOCOL {
> > >   EFI_MM_COMMUNICATE Communicate;
> > >   } EFI_MM_COMMUNICATION_PROTOCOL;
> > >
> > > Members
> > > Communicate
> > >   Sends/receives a message for a registered handler. See the
> > > Communicate()
> > >   function description.
> > >
> > > Description
> > >   This protocol provides runtime services for communicating between
> > > DXE drivers and a registered
> > >   MMI handler.
> > >
> > > EFI_MM_COMMUNICATION_PROTOCOL.Communicate()
> > > Summary
> > >   Communicates with a registered handler.
> > >
> > > Prototype
> > >   typedef
> > >   EFI_STATUS
> > >   (EFIAPI *EFI_MM_COMMUNICATE) (
> > >   IN CONST EFI_MM_COMMUNICATION_PROTOCOL *This,
> > >   IN OUT VOID *CommBuffer,
> > >   IN OUT UINTN *CommSize OPTIONAL
> > >   );
> > >
> > > Parameters
> > >   This - The EFI_MM_COMMUNICATION_PROTOCOL instance.
> > >   CommBuffer - Pointer to the buffer to convey into MMRAM.
> > >   CommSize - The size of the data buffer being passed in. On exit,
> > > the size of data being returned.
> > >                      Zero if the handler does not wish to reply
> > > with any data. This parameter is optional
> > >                      and may be NULL.
> > >
> > > Description
> > >   This function provides a service to send and receive messages
> > > from a registered UEFI service. The EFI_MM_COMMUNICATION_PROTOCOL
> > > driver is responsible for doing any of the
> > >   copies such that the data lives in boot-service-accessible RAM.
> > >   A given implementation of the EFI_MM_COMMUNICATION_PROTOCOL may
> > > choose to use the EFI_MM_CONTROL_PROTOCOL for effecting the mode
> > > transition, or it may use some other method.
> > >   The agent invoking the communication interface at runtime may be
> > > virtually mapped. The MM infrastructure code and handlers, on the
> > > other hand, execute in physical mode. As a result, the non-MM
> > > agent,
> > >   which may be executing in the virtual-mode OS context (as a
> > > result of an OS invocation of the UEFI SetVirtualAddressMap()
> > > service), should use a contiguous memory buffer with a physical
> > > address before
> > >   invoking this service. If the virtual address of the buffer is
> > > used, the MM Driver may not know how to do the appropriate virtual-
> > > to-physical conversion.
> > >   To avoid confusion in interpreting frames, the CommunicateBuffer
> > > parameter should always begin with EFI_MM_COMMUNICATE_HEADER, which
> > > is defined in Related Definitions below.
> > >   The header data is mandatory for messages sent into the MM agent.
> > >   If the CommSize parameter is omitted the MessageLength field in
> > > the EFI_MM_COMMUNICATE_HEADER,
> > >   in conjunction with the size of the header itself, can be used to
> > > ascertain the total size of the communication payload.
> > >   If the MessageLength is zero, or too large for the MM
> > > implementation to manage, the MM implementation must update the
> > > MessageLength to reflect the size of the Data buffer that it can
> > > tolerate.
> > >   If the CommSize parameter is passed into the call, but the
> > > integer it points to, has a value of 0, then this must be updated
> > > to reflect the maximum size of the CommBuffer that the
> > > implementation can tolerate.
> > >   Once inside of MM, the MM infrastructure will call all registered
> > > handlers with the same HandlerType as the GUID specified by
> > > HeaderGuid and the CommBuffer pointing to Data.
> > >   This function is not reentrant.
> > >   The standard header is used at the beginning of the
> > > EFI_MM_INITIALIATION_HEADER structure during MM initialization. See
> > > "Related Definitions" below for more information.
> > >
> > > Related Definitions
> > >   typedef struct {
> > >   EFI_GUID HeaderGuid;
> > >   UINTN MessageLength;
> > >   UINT8 Data[ANYSIZE_ARRAY];
> > >   } EFI_MM_COMMUNICATE_HEADER;
> > >
> > >   HeaderGuid - Allows for disambiguation of the message format.
> > > Type EFI_GUID is defined in
> > >                        InstallProtocolInterface() in the UEFI
> > > Specification.
> > >   MessageLength - Describes the size of Data (in bytes) and does
> > > not include the size of the header.
> > >   Data - Designates an array of bytes that is MessageLength in
> > > size.
> > >
> > > Status Codes Returned
> > >   EFI_SUCCESS - The message was successfully posted.
> > >   EFI_INVALID_PARAMETER - The buffer was NULL.
> > >   EFI_BAD_BUFFER_SIZE - The buffer is too large for the MM
> > > implementation. If this error is
> > >                                            returned, the
> > > MessageLength field in the CommBuffer
> > >                                            header or the integer
> > > pointed by CommSize, are updated to reflect
> > >                                            the maximum payload size
> > > the implementation can accommodate.
> > >                                            See the function
> > > description above for more details.
> > >   EFI_ACCESS_DENIED - The CommunicateBuffer parameter or CommSize
> > >                                         parameter, if not omitted,
> > > are in address range that cannot be
> > >                                         accessed by the MM
> > > environment.
> > >
> > > This patchset implements it on AARCH64 Platform.
> > > ***
> > >
> > > Supreeth Venkatesh (3):
> > >   ArmPkg/Drivers: Add EFI_MM_COMMUNICATION_PROTOCOL DXE driver.
> > >   ArmPkg/Drivers: Add ArmMmCommunication Driver information file.
> > >   ArmPkg: Add PCDs needed for MM communication driver.
> > >
> > >  ArmPkg/ArmPkg.dec                                  |   3 +
> > >  .../Drivers/MmCommunicationDxe/MmCommunication.c   | 314
> > > +++++++++++++++++++++
> > >  .../Drivers/MmCommunicationDxe/MmCommunication.inf |  50 ++++
> > >  3 files changed, 367 insertions(+)
> > >  create mode 100644
> > > ArmPkg/Drivers/MmCommunicationDxe/MmCommunication.c
> > >  create mode 100644
> > > ArmPkg/Drivers/MmCommunicationDxe/MmCommunication.inf
> > >
> > > --
> > > 2.14.1
> > >