Hi Rob, Thanks for reviewing, please see below inline comments.
On Mon, Feb 01, 2016 at 08:08:28AM -0600, Rob Herring wrote: > On Mon, Feb 01, 2016 at 09:34:44PM +0800, Leo Yan wrote: > > Document DT binding for Hisilicon Hi6220 mailbox driver. > > > > Signed-off-by: Leo Yan <[email protected]> > > --- > > .../bindings/mailbox/hisilicon,hi6220-mailbox.txt | 90 > > ++++++++++++++++++++++ > > 1 file changed, 90 insertions(+) > > create mode 100644 > > Documentation/devicetree/bindings/mailbox/hisilicon,hi6220-mailbox.txt > > > > diff --git > > a/Documentation/devicetree/bindings/mailbox/hisilicon,hi6220-mailbox.txt > > b/Documentation/devicetree/bindings/mailbox/hisilicon,hi6220-mailbox.txt > > new file mode 100644 > > index 0000000..96e6acc > > --- /dev/null > > +++ b/Documentation/devicetree/bindings/mailbox/hisilicon,hi6220-mailbox.txt > > @@ -0,0 +1,90 @@ > > +Hisilicon Hi6220 Mailbox Driver > > +=============================== > > + > > +Hisilicon Hi6220 mailbox supports up to 32 channels. Each channel > > +is unidirectional with a maximum message size of 8 words. I/O is > > +performed using register access (there is no DMA) and the cell > > +raises an interrupt when messages are received. > > + > > +Mailbox Device Node: > > +==================== > > + > > +Required properties: > > +-------------------- > > +- compatible: Shall be "hisilicon,hi6220-mbox" > > +- reg: Contains the mailbox register address range > > (base > > + address and length); the first item is for IPC > > + registers, the second item is shared buffer for > > + slots. > > +- #mbox-cells Common mailbox binding property to identify the > > number > > + of cells required for the mailbox specifier. Should be > > 1. > > +- interrupts: Contains the interrupt information for the > > mailbox > > + device. The format is dependent on which interrupt > > + controller the SoCs use. > > + > > +Optional Properties: > > +-------------------- > > +- hi6220,mbox-tx-noirq: Flag to allow the client user of this mailbox > > driver > > + to send messages without triggering a TX completion > > + interrupt. > > I don't think this belongs in DT. This should be a flag the client > driver sets when it sends messages. The client driver can set "tx_block = true" so use this flag indicates the client thread should be blocked until data is transmitted. But low level mailbox driver can use two method to support "tx_block" mode: - One method is to avoid using interrupt and mailbox framework will poll with mailbox's idle flag which is set by remote processor automatically; - Another method is to use interrupt to notify data has been transmitted and interrupt handler will call completion function to wake up blocked client thread; So this flag is to distinguish these two different hardware mechanism. Do you think this is make sense or have other suggestion? > > + > > +Child Nodes: > > +============ > > +A child node is used for representing the actual sub-mailbox device that is > > +used for the communication between the host processor and a remote > > processor. > > +Each child node should have a unique node name across all the different > > +mailbox device nodes. > > + > > +Required properties: > > +-------------------- > > +- hi6220,mbox-tx: sub-mailbox descriptor property defining Tx channel > > +- hi6220,mbox-rx: sub-mailbox descriptor property defining Rx channel > > + > > +Sub-mailbox Descriptor Data > > +--------------------------- > > +Each of the above hi6220,mbox-tx and hi6220,mbox-rx properties should have > > 3 > > +cells of data that represent the following: > > + Cell #1 (slot_id) - mailbox slot id used either for transmitting > > + (hi6220,mbox-tx) or for receiving (hi6220,mbox-rx) > > + Cell #2 (dst_irq) - irq identifier index number which used by MCU. > > + Cell #3 (ack_irq) - irq identifier index number with generating a tx/rx > > + interrupt to application processor, mailbox driver > > + used this id to acknowledge interrupt. > > + > > +Example: > > +-------- > > + > > + mailbox: mailbox@F7510000 { > > + #mbox-cells = <1>; > > + compatible = "hisilicon,hi6220-mbox"; > > + reg = <0x0 0xF7510000 0x0 0x1000>, /* IPC_S */ > > + <0x0 0x06DFF800 0x0 0x0800>; /* Mailbox */ > > + interrupt-parent = <&gic>; > > + interrupts = <GIC_SPI 94 IRQ_TYPE_LEVEL_HIGH>; > > + mbox_stub_clock: mbox_stub_clock { > > + hi6220,mbox-rx = <0 1 10>; > > + hi6220,mbox-tx = <1 0 11>; > > + }; > > + }; > > + > > + > > +Mailbox client > > +=============== > > + > > +"mboxes" and the optional "mbox-names" (please see > > +Documentation/devicetree/bindings/mailbox/mailbox.txt for details). Each > > value > > +of the mboxes property should contain a phandle to the mailbox controller > > +device node and second argument is the channel index. It must be 0 > > (hardware > > 0? But the example has 1. Will fix. Thanks, Leo Yan > > +support only one channel). The equivalent "mbox-names" property value can > > be > > +used to give a name to the communication channel to be used by the client > > user. > > + > > +Example: > > +-------- > > + > > + stub_clock: stub_clock { > > + compatible = "hisilicon,hi6220-stub-clk"; > > + hisilicon,hi6220-clk-sram = <&sram>; > > + #clock-cells = <1>; > > + mbox-names = "mbox-tx"; > > + mboxes = <&mailbox 1>; > > + }; > > -- > > 1.9.1 > >
