RE: [RFC LINUX PATCH] Dcoumentation: dt: mailbox: Add Xilinx IPI Mailbox

Jiaying Liang
2017-09-22T06:05:24Z

> -----Original Message-----
> From: Wendy Liang [mailto:wendy.liang@xilinx.com]
> Sent: Thursday, September 21, 2017 3:59 PM
> To: linux-kernel@vger.kernel.org
> Cc: jassisinghbrar@gmail.com; Cyril Chemparathy <cyrilc@xilinx.com>;
> Michal Simek <michals@xilinx.com>; Jiaying Liang <jliang@xilinx.com>
> Subject: [RFC LINUX PATCH] Dcoumentation: dt: mailbox: Add Xilinx IPI
> Mailbox
>
> Xilinx ZynqMP IPI(Inter Processor Interrupt) is a hardware block in ZynqMP
> SoC used for the communication between various processor systems.
>
> Signed-off-by: Wendy Liang <jliang@xilinx.com>
> ---
> .../bindings/mailbox/xlnx,zynqmp-ipi-mailbox.txt | 88
> ++++++++++++++++++++++
> 1 file changed, 88 insertions(+)
> create mode 100644
> Documentation/devicetree/bindings/mailbox/xlnx,zynqmp-ipi-mailbox.txt
>
> diff --git a/Documentation/devicetree/bindings/mailbox/xlnx,zynqmp-ipi-
> mailbox.txt b/Documentation/devicetree/bindings/mailbox/xlnx,zynqmp-ipi-
> mailbox.txt
> new file mode 100644
> index 0000000..5d915d1
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mailbox/xlnx,zynqmp-ipi-mailbox.
> +++ txt
> @@ -0,0 +1,88 @@
> +Xilinx IPI Mailbox Driver
> +========================================
> +
> +The Xilinx IPI(Inter Processor Interrupt) mailbox driver is a mailbox
> +controller that manages the messaging between two IPI agents. Each IPI
> +mailbox has request and response buffers between the two IPI agents.
> +
> ++-------------------------------------+
> +| | Xilinx ZynqMP IPI Mailbox
> +| Controller|
> +| |
> +| +-------------+
> +| | SMC |
> +| | |
> ++--------+--------------+------+------+
> + | |
> + | +-----------------+
> + | | ATF (ARM trusted firmware)
> + | |
> ++-------------------------------------+
> + | | Hardware
> + | |
> + +--------------------------------------+
> + | |
> + +----------------------+ +-----------+ |
> + | | Buffers between | | IPI Agent | |
> + | | two IPI agents | | Registers | |
> + | +--------------------+ +-----------+ |
> + | |
> + | Xilinx ZynqMP IPI |
> + +--------------------------------------+
> +
> +
> +Message Manager Device Node:
> +===========================
> +Required properties:
> +--------------------
> +- compatible: Shall be: "xlnx,zynqmp-ipi-mailbox"
> +- ipi-smc-fid-base Base offset of SMC function IDs for IPI mailbox SMC.
> + It contains the IPI IDs of the two IPI agents.
> +- reg: IPI request and response buffers address range. It
> + can be the IPI buffers from the hardware or it can
> + be carved out shared memory.
> +- reg-names: Reg resource name of the IPI request and response
> + buffers.
> +- #mbox-cells: Shall be 1. Contains the logical channel IDs of the
> + channels on the IPI mailbox.
> +- interrupt-parent: Phandle for the interrupt controller.
> +- interrupts: Interrupt mapping.
> +
> +Required properties:
> +--------------------
> +- method: The method of accessing the IPI agent registers.
> + Permitted values are: "smc" and "hvc". Default is
> + "smc".
> +Example:
> +------------
> + /* APU IPI mailbox driver */
> + ipis {
> + #address-cells = <1>;
> + #size-cells = <0>;
> + ipi_mailbox_apu_rpu0: ipi_mailbox@0 {
> + compatible = "xlnx,zynqmp-ipi-mailbox";
> + reg = <0 0xff990400 40>;
> + reg-names = "apu-rpu0";
> + ipi-smc-fid-base = <0x1010>;
> + method = "smc";
> + #mbox-cells = <1>;
> + interrupt-parent = <&gic>;
> + interrupts = <0 35 4>;
> + };
> + ipi_mailbox_apu_rpu1: ipi_mailbox@1 {
> + compatible = "xlnx,zynqmp-ipi-mailbox";
> + reg = <0 0xff990440 40>;
> + reg-names = "apu-rpu1";
> + ipi-smc-fid-base = <0x1020>;
> + method = "smc";
> + #mbox-cells = <1>;
> + interrupt-parent = <&gic>;
> + interrupts = <0 35 4>;
> + };
> + };
> + device0: device0 {
> + ...
> + mbox-names = "rpu0", "rpu1",
> + mboxes = <&ipi_mailbox_apu_rpu0 0>,
> + < &ipi_mailbox_apu_rpu1 0>;
> + };
> --
> 2.7.4

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