soc: bcm: bcm2835-pm: Add support for power domains under a new binding.

This provides a free software alternative to raspberrypi-power.c's
firmware calls to manage power domains.  It also exposes a reset line,
where previously the vc4 driver had to try to force power off the
domain in order to trigger a reset.

Signed-off-by: Eric Anholt <eric@anholt.net>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>

include/dt-bindings/soc/bcm2835-pm.h

@@ -0,0 +1,28 @@
+/* SPDX-License-Identifier: (GPL-2.0+ OR MIT) */
+
+#ifndef _DT_BINDINGS_ARM_BCM2835_PM_H
+#define _DT_BINDINGS_ARM_BCM2835_PM_H
+
+#define BCM2835_POWER_DOMAIN_GRAFX		0
+#define BCM2835_POWER_DOMAIN_GRAFX_V3D		1
+#define BCM2835_POWER_DOMAIN_IMAGE		2
+#define BCM2835_POWER_DOMAIN_IMAGE_PERI		3
+#define BCM2835_POWER_DOMAIN_IMAGE_ISP		4
+#define BCM2835_POWER_DOMAIN_IMAGE_H264		5
+#define BCM2835_POWER_DOMAIN_USB		6
+#define BCM2835_POWER_DOMAIN_DSI0		7
+#define BCM2835_POWER_DOMAIN_DSI1		8
+#define BCM2835_POWER_DOMAIN_CAM0		9
+#define BCM2835_POWER_DOMAIN_CAM1		10
+#define BCM2835_POWER_DOMAIN_CCP2TX		11
+#define BCM2835_POWER_DOMAIN_HDMI		12
+
+#define BCM2835_POWER_DOMAIN_COUNT		13
+
+#define BCM2835_RESET_V3D			0
+#define BCM2835_RESET_ISP			1
+#define BCM2835_RESET_H264			2
+
+#define BCM2835_RESET_COUNT			3
+
+#endif /* _DT_BINDINGS_ARM_BCM2835_PM_H */