On Mon, Feb 1, 2016 at 8:53 PM, Leo Yan <leo.yan@xxxxxxxxxx> wrote: > 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 <leo.yan@xxxxxxxxxx> >> > --- >> > .../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. > Yes, but the 'tx_block' feature is provided by the core. The controller driver should not need to know how the client works. > But low level mailbox driver can use two method to support "tx_block" > mode: > No, as I said, provider shouldn't care about consumers.. > - 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; > If it is possible to have either 'idle flag set' or irq generated (not both) by the remote, then you may sell the hi6220,mbox-tx-noirq property as a "f/w feature" ... but still not for the sake of tx_block. >> > + >> > +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>; > This looks like meant for the client node... mbox-names = "mbox-tx", "mbox-rx"; mboxes = <&mailbox 1 0 11>, <&mailbox 0 1 10>; -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html