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Diffstat (limited to 'Documentation/devicetree/bindings/video/simple-framebuffer.txt')
-rw-r--r-- | Documentation/devicetree/bindings/video/simple-framebuffer.txt | 86 |
1 files changed, 0 insertions, 86 deletions
diff --git a/Documentation/devicetree/bindings/video/simple-framebuffer.txt b/Documentation/devicetree/bindings/video/simple-framebuffer.txt deleted file mode 100644 index 4474ef6e0..000000000 --- a/Documentation/devicetree/bindings/video/simple-framebuffer.txt +++ /dev/null @@ -1,86 +0,0 @@ -Simple Framebuffer - -A simple frame-buffer describes a frame-buffer setup by firmware or -the bootloader, with the assumption that the display hardware has already -been set up to scan out from the memory pointed to by the reg property. - -Since simplefb nodes represent runtime information they must be sub-nodes of -the chosen node (*). Simplefb nodes must be named "framebuffer@<address>". - -If the devicetree contains nodes for the display hardware used by a simplefb, -then the simplefb node must contain a property called "display", which -contains a phandle pointing to the primary display hw node, so that the OS -knows which simplefb to disable when handing over control to a driver for the -real hardware. The bindings for the hw nodes must specify which node is -considered the primary node. - -It is advised to add display# aliases to help the OS determine how to number -things. If display# aliases are used, then if the simplefb node contains a -"display" property then the /aliases/display# path must point to the display -hw node the "display" property points to, otherwise it must point directly -to the simplefb node. - -If a simplefb node represents the preferred console for user interaction, -then the chosen node's stdout-path property should point to it, or to the -primary display hw node, as with display# aliases. If display aliases are -used then it should be set to the alias instead. - -It is advised that devicetree files contain pre-filled, disabled framebuffer -nodes, so that the firmware only needs to update the mode information and -enable them. This way if e.g. later on support for more display clocks get -added, the simplefb nodes will already contain this info and the firmware -does not need to be updated. - -If pre-filled framebuffer nodes are used, the firmware may need extra -information to find the right node. In that case an extra platform specific -compatible and platform specific properties should be used and documented, -see e.g. simple-framebuffer-sunxi.txt . - -Required properties: -- compatible: "simple-framebuffer" -- reg: Should contain the location and size of the framebuffer memory. -- width: The width of the framebuffer in pixels. -- height: The height of the framebuffer in pixels. -- stride: The number of bytes in each line of the framebuffer. -- format: The format of the framebuffer surface. Valid values are: - - r5g6b5 (16-bit pixels, d[15:11]=r, d[10:5]=g, d[4:0]=b). - - a8b8g8r8 (32-bit pixels, d[31:24]=a, d[23:16]=b, d[15:8]=g, d[7:0]=r). - -Optional properties: -- clocks : List of clocks used by the framebuffer. Clocks listed here - are expected to already be configured correctly. The OS must - ensure these clocks are not modified or disabled while the - simple framebuffer remains active. -- display : phandle pointing to the primary display hardware node - -Example: - -aliases { - display0 = &lcdc0; -} - -chosen { - framebuffer0: framebuffer@1d385000 { - compatible = "simple-framebuffer"; - reg = <0x1d385000 (1600 * 1200 * 2)>; - width = <1600>; - height = <1200>; - stride = <(1600 * 2)>; - format = "r5g6b5"; - clocks = <&ahb_gates 36>, <&ahb_gates 43>, <&ahb_gates 44>; - display = <&lcdc0>; - }; - stdout-path = "display0"; -}; - -soc@01c00000 { - lcdc0: lcdc@1c0c000 { - compatible = "allwinner,sun4i-a10-lcdc"; - ... - }; -}; - - -*) Older devicetree files may have a compatible = "simple-framebuffer" node -in a different place, operating systems must first enumerate any compatible -nodes found under chosen and then check for other compatible nodes. |