docs: astlpc: Describe some implementation details
However, isolate the details to their own section near the end of the
document so as not to disrupt specification of the binding behaviour.
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Change-Id: I7d4ab48b5659caa185a3f665857daee50dfb5a61
diff --git a/docs/bindings/vendor-astlpc.md b/docs/bindings/vendor-astlpc.md
index 094ac1c..2c81c95 100644
--- a/docs/bindings/vendor-astlpc.md
+++ b/docs/bindings/vendor-astlpc.md
@@ -285,6 +285,24 @@
| 15 | The BMC observes IBF is set and the command is `Rx Complete`. |
| 16 | The BMC regains ownership of its Tx buffer |
+## Implementation Notes
+
+On the BMC the initial prototype implementation makes use of the following
+components:
+
+* An LPC KCS device exposed by a [binding-specific kernel driver][mctp-driver]
+* The reserved memory mapped by the LPC2AHB bridge via the [aspeed-lpc-ctrl
+ driver][aspeed-lpc-ctrl]
+* The astlpc binding found in [libmctp][libmctp]
+
+[mctp-driver]: https://github.com/openbmc/linux/commit/9a3b539a175cf4fe1f8fc2997e8a91abec25c37f
+[aspeed-lpc-ctrl]: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/soc/aspeed/aspeed-lpc-ctrl.c?h=v5.7
+[libmctp]: https://github.com/openbmc/libmctp
+
+From the host side, the LPC Firmware and KCS IO cycles are driven by
+free-standing firmware. Some firmwares exploit [libmctp][libmctp] by
+implementing the driver hooks for direct access to the LPC devices.
+
## Alternatives Considered
### The KCS MCTP Binding (DSP0254)