[PATCH 1/5] drivers/accel: Introduce subsystem

[Olof Johansson]

We're starting to see more of these kind of devices, the current
upcoming wave will likely be around machine learning and inference
engines. A few drivers have been added to drivers/misc for this, but
it's timely to make it into a separate group of drivers/subsystem, to
make it easier to find them, and to encourage collaboration between
contributors.

Over time, we expect to build shared frameworks that the drivers will
make use of, but how that framework needs to look like to fill the needs
is still unclear, and the best way to gain that knowledge is to give the
disparate implementations a shared location.

There has been some controversy around expectations for userspace
stacks being open. The clear preference is to see that happen, and any
driver and platform stack that is delivered like that will be given
preferential treatment, and at some point in the future it might
become the requirement. Until then, the bare minimum we need is an
open low-level userspace such that the driver and HW interfaces can be
exercised if someone is modifying the driver, even if the full details
of the workload are not always available.

Bootstrapping this with myself and Greg as maintainers (since the current
drivers will be moving out of drivers/misc). Looking forward to expanding
that group over time.

Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Olof Johansson <olof@xxxxxxxxx>
---
 MAINTAINERS            |  8 ++++++++
 drivers/Kconfig        |  2 ++
 drivers/Makefile       |  1 +
 drivers/accel/Kconfig  | 16 ++++++++++++++++
 drivers/accel/Makefile |  5 +++++
 5 files changed, 32 insertions(+)
 create mode 100644 drivers/accel/Kconfig
 create mode 100644 drivers/accel/Makefile

diff --git a/MAINTAINERS b/MAINTAINERS
index ddcdc29dfe1f6..8a9bbaf8f6e90 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -7033,6 +7033,14 @@ W:	https://linuxtv.org
 S:	Supported
 F:	drivers/media/platform/sti/hva
 
+HW ACCELERATOR OFFLOAD SUBSYSTEM
+M:	Olof Johansson <olof@xxxxxxxxx>
+M:	Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
+L:	linux-accelerators@xxxxxxxxxxxxxxxx
+S:	Supported
+F:	drivers/accel/
+F:	Documentation/accelerators/
+
 HWPOISON MEMORY FAILURE HANDLING
 M:	Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx>
 L:	linux-mm@xxxxxxxxx
diff --git a/drivers/Kconfig b/drivers/Kconfig
index 4f9f99057ff85..3cc461f325569 100644
--- a/drivers/Kconfig
+++ b/drivers/Kconfig
@@ -228,4 +228,6 @@ source "drivers/siox/Kconfig"
 
 source "drivers/slimbus/Kconfig"
 
+source "drivers/accel/Kconfig"
+
 endmenu
diff --git a/drivers/Makefile b/drivers/Makefile
index 04da7876032cc..e4be06579cc5d 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -186,3 +186,4 @@ obj-$(CONFIG_MULTIPLEXER)	+= mux/
 obj-$(CONFIG_UNISYS_VISORBUS)	+= visorbus/
 obj-$(CONFIG_SIOX)		+= siox/
 obj-$(CONFIG_GNSS)		+= gnss/
+obj-$(CONFIG_ACCEL)		+= accel/
diff --git a/drivers/accel/Kconfig b/drivers/accel/Kconfig
new file mode 100644
index 0000000000000..13b36c0398895
--- /dev/null
+++ b/drivers/accel/Kconfig
@@ -0,0 +1,16 @@
+#
+# Drivers for hardware offload accelerators
+# See Documentation/accel/README.rst for more details
+#
+
+menuconfig ACCEL
+	bool "Hardware offload accelerator support"
+        help
+	  HW offload accelerators are used for high-bandwidth workloads
+	  where a higher-level kernel/userspace interface isn't suitable.
+
+if ACCEL
+
+comment "HW Accellerator drivers"
+
+endif
diff --git a/drivers/accel/Makefile b/drivers/accel/Makefile
new file mode 100644
index 0000000000000..343bbb8f45a14
--- /dev/null
+++ b/drivers/accel/Makefile
@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for accel devices
+#
+
-- 
2.11.0