On Fri, 2017-02-17 at 19:28 +0100, Lucas Stach wrote:

The Prefetch Resolve Engine is a prefetch and tile resolve engine which prefetches display data from DRAM to an internal SRAM region. It has a single clock for configuration register access and the functional units. A single shared interrupt is used for status and error signaling.

The only external dependency is the SRAM region to use for the prefetch double buffer.

Signed-off-by: Lucas Stach l.stach@pengutronix.de

.../bindings/display/imx/fsl-imx-drm.txt | 26 ++++++++++++++++++++++ 1 file changed, 26 insertions(+)

diff --git a/Documentation/devicetree/bindings/display/imx/fsl-imx-drm.txt b/Documentation/devicetree/bindings/display/imx/fsl-imx-drm.txt index 971c3eedb1c7..1bd777d7c37d 100644 --- a/Documentation/devicetree/bindings/display/imx/fsl-imx-drm.txt +++ b/Documentation/devicetree/bindings/display/imx/fsl-imx-drm.txt @@ -53,6 +53,32 @@ ipu: ipu@18000000 { }; };

+Freescale i.MX PRE (Prefetch Resolve Engine) +============================================

+Required properties: +- compatible: should be "fsl,imx6qp-pre" +- reg: should be register base and length as documented in the

• datasheet

+- clocks : phandle to the PRE axi clock input, as described

• in Documentation/devicetree/bindings/clock/clock-bindings.txt and
• Documentation/devicetree/bindings/clock/imx6q-clock.txt.

+- clock-names: should be "axi" +- interrupts: should contain the PRE interrupt +- fsl,ocram: phandle pointing to the mmio-sram device node, that should be

• used for the PRE SRAM double buffer.

+example:

+pre@021c8000 {

• compatible = "fsl,imx6qp-pre";
• reg = <0x021c8000 0x1000>;
• interrupts = <GIC_SPI 90 IRQ_TYPE_EDGE_RISING>;
• clocks = <&clks IMX6QDL_CLK_PRE0>;
• clock-names = "axi";
• fsl,ocram = <&ocram2>;

Nitpick: the CODA property for this is called iram. Should we do the same here in case the PRE is later used on other SoCs that call their on-chip SRAM differently? There is no mention of OCRAM in the PRE chapter in the i.MX6QP reference manual, but Figures 38-1 and 38-5 mention an "IRAM Double Buffer".

+};

Parallel display support

regards Philipp