Add README
Describe code organization in the README.
Change-Id: Iaa180fd5663c9f7fa0eba4778cb2ae7bc936a369
Signed-off-by: Deepak Kodihalli <dkodihal@in.ibm.com>
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+# Code Organization
+At a high-level, code in this repository belongs to one of the following three
+components.
+
+## libpldm
+This is a library which deals with the encoding and decoding of PLDM messages.
+It should be possible to use this library by projects other than OpenBMC, and
+hence certain constraints apply to it:
+- keeping it light weight
+- implementation in C
+- minimal dynamic memory allocations
+- endian-safe
+- no OpenBMC specific dependencies
+
+Source files are named according to the PLDM Type, for eg base.[h/c], fru.[h/c],
+etc.
+
+Given a PLDM command "foo", the library will provide the following API:
+For the Requester function:
+```
+encode_foo_req() - encode a foo request
+decode_foo_resp() - decode a response to foo
+```
+For the Responder function:
+```
+decode_foo_req() - decode a foo request
+encode_foo_resp() - encode a response to foo
+```
+The library also provides API to pack and unpack PLDM headers.
+
+## libpldmresponder
+This library provides handlers for incoming PLDM request messages. It provides
+for a registration as well as a plug-in mechanism. The library is implemented in
+modern C++, and handles OpenBMC's platform specifics.
+
+The handlers are of the form
+```
+Response handler(Request payload, size_t payloadLen)
+```
+
+Source files are named according to the PLDM Type, for eg base.[hpp/cpp],
+fru.[hpp/cpp], etc.
+
+## daemon
+This is the PLDM daemon application that deals with various aspects of the
+requester and responder functions, as explained at
+https://github.com/openbmc/docs/blob/master/designs/pldm-stack.md.
+
+## TODO
+Consider hosting libpldm above in a repo of its own, probably even outside the
+OpenBMC project? A separate repo would enable something like git submodule.