1 # SPDX-License-Identifier: GPL-2.0
4 $id: http://devicetree.org/schemas/display/simple-framebuffer.yaml#
5 $schema: http://devicetree.org/meta-schemas/core.yaml#
7 title: Simple Framebuffer
10 - Hans de Goede <hdegoede@redhat.com>
13 A simple frame-buffer describes a frame-buffer setup by firmware or
14 the bootloader, with the assumption that the display hardware has
15 already been set up to scan out from the memory pointed to by the
18 Since simplefb nodes represent runtime information they must be
19 sub-nodes of the chosen node (*). Simplefb nodes must be named
20 framebuffer@<address>.
22 If the devicetree contains nodes for the display hardware used by a
23 simplefb, then the simplefb node must contain a property called
24 display, which contains a phandle pointing to the primary display
25 hw node, so that the OS knows which simplefb to disable when handing
26 over control to a driver for the real hardware. The bindings for the
27 hw nodes must specify which node is considered the primary node.
29 It is advised to add display# aliases to help the OS determine how
30 to number things. If display# aliases are used, then if the simplefb
31 node contains a display property then the /aliases/display# path
32 must point to the display hw node the display property points to,
33 otherwise it must point directly to the simplefb node.
35 If a simplefb node represents the preferred console for user
36 interaction, then the chosen node stdout-path property should point
37 to it, or to the primary display hw node, as with display#
38 aliases. If display aliases are used then it should be set to the
41 It is advised that devicetree files contain pre-filled, disabled
42 framebuffer nodes, so that the firmware only needs to update the
43 mode information and enable them. This way if e.g. later on support
44 for more display clocks get added, the simplefb nodes will already
45 contain this info and the firmware does not need to be updated.
47 If pre-filled framebuffer nodes are used, the firmware may need
48 extra information to find the right node. In that case an extra
49 platform specific compatible and platform specific properties should
50 be used and documented.
57 - apple,simple-framebuffer
58 - allwinner,simple-framebuffer
59 - amlogic,simple-framebuffer
60 - const: simple-framebuffer
61 - const: simple-framebuffer
64 description: Location and size of the framebuffer memory
67 description: List of clocks used by the framebuffer.
70 description: List of power domains used by the framebuffer.
73 $ref: /schemas/types.yaml#/definitions/uint32
74 description: Width of the framebuffer in pixels
77 $ref: /schemas/types.yaml#/definitions/uint32
78 description: Height of the framebuffer in pixels
81 $ref: /schemas/types.yaml#/definitions/uint32
82 description: Number of bytes of a line in the framebuffer
86 Format of the framebuffer:
87 * `a1r5g5b5` - 16-bit pixels, d[15]=a, d[14:10]=r, d[9:5]=g, d[4:0]=b
88 * `a2r10g10b10` - 32-bit pixels, d[31:30]=a, d[29:20]=r, d[19:10]=g, d[9:0]=b
89 * `a8b8g8r8` - 32-bit pixels, d[31:24]=a, d[23:16]=b, d[15:8]=g, d[7:0]=r
90 * `a8r8g8b8` - 32-bit pixels, d[31:24]=a, d[23:16]=r, d[15:8]=g, d[7:0]=b
91 * `r5g6b5` - 16-bit pixels, d[15:11]=r, d[10:5]=g, d[4:0]=b
92 * `r5g5b5a1` - 16-bit pixels, d[15:11]=r, d[10:6]=g, d[5:1]=b d[1:0]=a
93 * `r8g8b8` - 24-bit pixels, d[23:16]=r, d[15:8]=g, d[7:0]=b
94 * `x1r5g5b5` - 16-bit pixels, d[14:10]=r, d[9:5]=g, d[4:0]=b
95 * `x2r10g10b10` - 32-bit pixels, d[29:20]=r, d[19:10]=g, d[9:0]=b
96 * `x8r8g8b8` - 32-bit pixels, d[23:16]=r, d[15:8]=g, d[7:0]=b
110 $ref: /schemas/types.yaml#/definitions/phandle
111 description: Primary display hardware node
114 description: Pipeline used by the framebuffer on Allwinner SoCs
122 - de_fe0-de_be0-lcd0-hdmi
123 - de_fe0-de_be0-lcd0-tve0
130 description: Pipeline used by the framebuffer on Amlogic SoCs
136 "^[a-zA-Z0-9-]+-supply$":
137 $ref: /schemas/types.yaml#/definitions/phandle
139 Regulators used by the framebuffer. These should be named
140 according to the names in the device design.
143 # The binding requires also reg, width, height, stride and format,
144 # but usually they will be filled by the bootloader.
152 const: allwinner,simple-framebuffer
162 const: amlogic,simple-framebuffer
169 additionalProperties: false
176 #address-cells = <1>;
180 #address-cells = <1>;
182 framebuffer0: framebuffer@1d385000 {
183 compatible = "allwinner,simple-framebuffer", "simple-framebuffer";
184 allwinner,pipeline = "de_be0-lcd0";
185 reg = <0x1d385000 3840000>;
190 clocks = <&ahb_gates 36>, <&ahb_gates 43>, <&ahb_gates 44>;
191 lcd-supply = <®_dc1sw>;