drm/v3d: Add support for V3D v4.2.

No compatible string for it yet, just the version-dependent changes.
They've now tied the hub and the core interrupt lines into a single
interrupt line coming out of the block.  It also turns out I made a
mistake in modeling the V3D v3.3 and v4.1 bridge as a part of V3D
itself -- the bridge is going away in favor of an external reset
controller in a larger HW module.

v2: Use consistent checks for whether we're on 4.2, and fix a leak in
    an error path.
v3: Use more general means of determining if the current 4.2 changes
    are in place, as apparently other platforms may switch back (noted
    by Dave).  Update the binding doc.
v4: Improve error handling for IRQ init.

Signed-off-by: Eric Anholt <eric@anholt.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20190308174336.7866-2-eric@anholt.net
Reviewed-by: Dave Emett <david.emett@broadcom.com>

1 files changed, 8 insertions, 3 deletions

diff --git a/Documentation/devicetree/bindings/gpu/brcm,bcm-v3d.txt b/Documentation/devicetree/bindings/gpu/brcm,bcm-v3d.txt
index c907aa8dd755..b2df82b44625 100644
--- a/Documentation/devicetree/bindings/gpu/brcm,bcm-v3d.txt
+++ b/Documentation/devicetree/bindings/gpu/brcm,bcm-v3d.txt
@@ -6,15 +6,20 @@ For V3D 2.x, see brcm,bcm-vc4.txt.
 Required properties:
 - compatible:	Should be "brcm,7268-v3d" or "brcm,7278-v3d"
 - reg:		Physical base addresses and lengths of the register areas
-- reg-names:	Names for the register areas.  The "hub", "bridge", and "core0"
+- reg-names:	Names for the register areas.  The "hub" and "core0"
 		  register areas are always required.  The "gca" register area
-		  is required if the GCA cache controller is present.
+		  is required if the GCA cache controller is present.  The
+		  "bridge" register area is required if an external reset
+		  controller is not present.
 - interrupts:	The interrupt numbers.  The first interrupt is for the hub,
-		  while the following interrupts are for the cores.
+		  while the following interrupts are separate interrupt lines
+		  for the cores (if they don't share the hub's interrupt).
 		  See bindings/interrupt-controller/interrupts.txt
 
 Optional properties:
 - clocks:	The core clock the unit runs on
+- resets:	The reset line for v3d, if not using a mapping of the bridge
+		  See bindings/reset/reset.txt
 
 v3d {
 	compatible = "brcm,7268-v3d";