GEN2 devices use a single CSR for PFVF messages, which leaves up to 10 bits
of payload per single message. While such amount is sufficient for the
currently defined messages, the transfer of bigger and more complex data
streams from the PF to the VF requires a new mechanism that extends the
protocol.
This patch adds a new layer on top of the basic PFVF messaging, called
Block Messages, to encapsulate up to 126 bytes of data in a single
logical message across multiple PFVF messages of new types (SMALL,
MEDIUM and LARGE BLOCK), including (sub)types (BLKMSG_TYPE) to carry the
information about the actual Block Message.
Regardless of the size, each Block Message uses a two bytes header,
containing the version and size, to allow for extension while
maintaining compatibility. The size and the types of Block Messages are
defined as follow:
- small block messages: up to 16 BLKMSG types of up to 30 bytes
- medium block messages: up to 8 BLKMSG types of up to 62 bytes
- large block messages: up to 4 BLKMSG types of up to 126 bytes
It effectively works as reading a byte at a time from a block device and
for each of these new Block Messages:
- the requestor (always a VF) can either request a specific byte of the
larger message, in order to retrieve the full message, or request the
value of the CRC calculated for a specific message up to the provided
size (to allow for messages to grow while maintaining forward
compatibility)
- the responder (always the PF) will either return a single data or CRC
byte, along with the indication of response type (or error).
This patch provides the basic infrastructure to perform the above
operations, without defining any new message.
As CRCs are required, this code now depends on the CRC8 module.
Note: as a consequence of the Block Messages design, sending multiple
PFVF messages in bursts, the interrupt rate limiting values on the PF are
increased.
Signed-off-by: Marco Chiappero <marco.chiappero@intel.com>
Co-developed-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
Signed-off-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
Reviewed-by: Fiona Trahe <fiona.trahe@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This implementation of the PFVF protocol was designed around the GEN2
devices and its CSR format. In order to support future generations,
which come with differently sized fields, change the definition of the PFVF
message and make it abstract by means of a new pfvf_message struct. Also,
introduce some utilities to translate to and from the new message format
and the device specific CSR format.
Signed-off-by: Marco Chiappero <marco.chiappero@intel.com>
Reviewed-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
Reviewed-by: Fiona Trahe <fiona.trahe@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Currently, any PF response to a VF request is fully parsed during the
interrupt handling. This way the individual response values are stored
into the accel_dev structure, preventing the caller to access and decode
the full response message itself.
Change this behavior, by letting the API return back the entire message
to the caller, in order to:
- keep correlated code together, that is, the (building of the)
request and the (decoding of the) response;
- avoid polluting the accel_dev data structure with unnecessary and at
times temporary values; only the entire message is stored in a
temporary buffer.
Signed-off-by: Marco Chiappero <marco.chiappero@intel.com>
Reviewed-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
Signed-off-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Reorganize the structure of the PFVF code by moving the content of
adf_pf2vf_msg.c and adf_vf2pf_msg.c.
The logic that handles high level messages has been moved to
adf_pfvf_pf_msg.c and adf_pfvf_vf_msg.c.
The implementation of low level communication primitives and the
protocol is now included in adf_pfvf_pf_proto.c and adf_pfvf_vf_proto.c.
In addition, the file adf_pf2vf_msg.h has been renamed in adf_pfvf_msg.h
since it common to PF and VF and the copyright date for the touched
files has been updated.
Signed-off-by: Marco Chiappero <marco.chiappero@intel.com>
Co-developed-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
Signed-off-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
