media: allegro: add Allegro DVT video IP core driver

Add a V4L2 mem-to-mem driver for Allegro DVT video IP cores as found in
the EV family of the Xilinx ZynqMP SoC. The Zynq UltraScale+ Device
Technical Reference Manual uses the term VCU (Video Codec Unit) for the
encoder, decoder and system integration block.

This driver takes care of interacting with the MicroBlaze MCU that
controls the actual IP cores. The IP cores and MCU are integrated in the
FPGA. The xlnx_vcu driver is responsible for configuring the clocks and
providing information about the codec configuration.

The driver currently only supports the H.264 video encoder.
Signed-off-by: Michael Tretter <m.tretter@pengutronix.de>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

MAINTAINERS

@@ -668,6 +668,13 @@ S:	Maintained
 F:	Documentation/i2c/busses/i2c-ali1563
 F:	drivers/i2c/busses/i2c-ali1563.c
 
+ALLEGRO DVT VIDEO IP CORE DRIVER
+M:	Michael Tretter <m.tretter@pengutronix.de>
+R:	Pengutronix Kernel Team <kernel@pengutronix.de>
+L:	linux-media@vger.kernel.org
+S:	Maintained
+F:	drivers/staging/media/allegro-dvt/
+
 ALLWINNER SECURITY SYSTEM
 M:	Corentin Labbe <clabbe.montjoie@gmail.com>
 L:	linux-crypto@vger.kernel.org

drivers/staging/media/Kconfig

@@ -20,6 +20,8 @@ menuconfig STAGING_MEDIA
 if STAGING_MEDIA && MEDIA_SUPPORT
 
 # Please keep them in alphabetic order
+source "drivers/staging/media/allegro-dvt/Kconfig"
+
 source "drivers/staging/media/bcm2048/Kconfig"
 
 source "drivers/staging/media/davinci_vpfe/Kconfig"

drivers/staging/media/Makefile

 # SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_VIDEO_ALLEGRO_DVT)	+= allegro-dvt/
 obj-$(CONFIG_I2C_BCM2048)	+= bcm2048/
 obj-$(CONFIG_VIDEO_IMX_MEDIA)	+= imx/
 obj-$(CONFIG_VIDEO_DM365_VPFE)	+= davinci_vpfe/

drivers/staging/media/allegro-dvt/Kconfig

+# SPDX-License-Identifier: GPL-2.0
+config VIDEO_ALLEGRO_DVT
+	tristate "Allegro DVT Video IP Core"
+	depends on VIDEO_DEV && VIDEO_V4L2
+	depends on ARCH_ZYNQMP || COMPILE_TEST
+	select V4L2_MEM2MEM_DEV
+	select VIDEOBUF2_DMA_CONTIG
+	select REGMAP
+	select REGMAP_MMIO
+	help
+	  Support for the encoder video IP core by Allegro DVT. This core is
+	  found for example on the Xilinx ZynqMP SoC in the EV family and is
+	  called VCU in the reference manual.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called allegro.

drivers/staging/media/allegro-dvt/Makefile

+# SPDX-License-Identifier: GPL-2.0
+allegro-objs := allegro-core.o
+
+obj-$(CONFIG_VIDEO_ALLEGRO_DVT) += allegro.o

drivers/staging/media/allegro-dvt/TODO

+TODO:
+
+- This driver is waiting for the stateful encoder spec and corresponding
+  v4l2-compliance tests to be finalized.