arch: fw: sof-zephyr hda io driver

sof-zephyr hda io driver architecture chapter

Signed-off-by: Michal Wasko <[email protected]>

Author: mwasko

architectures/firmware/sof-zephyr/rtos_layer/io_drivers/hda/hda_driver.rst

@@ -0,0 +1,50 @@
+.. _hda_driver:
+
+HD-A IO Driver
+##############
+
+.. uml:: images/hda_io_driver_deps.pu
+   :caption: HD-A IO Driver overview
+
+HD-A Gateways
+*************
+
+Gateway Node Addressing
+=======================
+
+There are four types of HD-A gateways. Note that the naming convention
+(inherited from c-spec) names the data flow direction based on the external
+entity's perspective. Therefore, "output" means that data comes to FW from the
+external source and "input" means that data is sent from FW to the external
+sink.
+
+.. uml:: images/hda_playback.pu
+   :caption: HD-A Playback
+
+.. uml:: images/hda_capture.pu
+   :caption: HD-A Capture
+
+HD-A Gateway types:
+  - HDA-A DMA Source,
+
+    - DMA Host Output,
+    - DMA Link Input,
+
+  - HDA-A DMA Sink,
+
+    - DMA Host Input,
+    - DMA Link Output
+
+HD-A to HDMI
+============
+
+There following options are available:
+
+ 1. Legacy HD/A (not recommended),
+ 2. HW chaining in the DSP (depends on HW support),
+ 3. SW chaining in the DSP (recommended),
+ 4. Full Copier-...-Copier pipeline (more resources required).
+
+The most resource-efficient way to do a simple HD/A to HD/A playback via the DSP
+is to use the "DMA Chaining" feature. FW provides an IPC command to connect two
+HD/A gateways with a simple data copier task running in the LL domain.

architectures/firmware/sof-zephyr/rtos_layer/io_drivers/hda/images/hda_capture.pu

@@ -0,0 +1,15 @@
+@startuml
+
+component "host capture" as hc
+
+package FW {
+	component "Host Input" as hi
+	component "Link Output" as lo
+}
+
+component "link capture" as lc
+hc <- hi
+hi <- lo
+lo <- lc
+
+@enduml

architectures/firmware/sof-zephyr/rtos_layer/io_drivers/hda/images/hda_io_driver_deps.pu

@@ -0,0 +1,12 @@
+
+@startuml
+allowmixing
+
+component "hd-a io driver" as io_drv
+component "hd-a gateway" as gateway
+component "hd-a dma" as dma
+
+io_drv -right-> gateway : provides
+gateway -down-> dma : use
+
+@enduml

architectures/firmware/sof-zephyr/rtos_layer/io_drivers/hda/images/hda_playback.pu

@@ -0,0 +1,15 @@
+@startuml
+
+component "host playback" as hp
+
+package FW {
+	component "Host Output" as ho
+	component "Link Input" as li
+}
+
+component "link playback" as lp
+hp -> ho
+ho -> li
+li -> lp
+
+@enduml

architectures/firmware/sof-zephyr/rtos_layer/io_drivers/index.rst

@@ -19,3 +19,11 @@ still in use as a substitute of Gateways.
 
 .. uml:: images/io_drivers_diagram.pu
    :caption: IO Drivers diagram
+
+Drivers
+*******
+
+.. toctree::
+   :maxdepth: 1
+
+   hda/hda_driver