Hi, On 02/28/18 02:28, Maxime Ripard wrote: > On Tue, Feb 27, 2018 at 08:27:12PM -0600, Samuel Holland wrote: >> This mailbox hardware is present in several Allwinner sun8i and sun50i >> SoCs. Add a device tree binding for it. >> >> Signed-off-by: Samuel Holland <samuel@xxxxxxxxxxxx> >> --- >> .../devicetree/bindings/mailbox/sunxi-msgbox.txt | 40 ++++++++++++++++++++++ >> 1 file changed, 40 insertions(+) >> create mode 100644 Documentation/devicetree/bindings/mailbox/sunxi-msgbox.txt >> >> diff --git a/Documentation/devicetree/bindings/mailbox/sunxi-msgbox.txt b/Documentation/devicetree/bindings/mailbox/sunxi-msgbox.txt >> new file mode 100644 >> index 000000000000..3b3ed7f870a0 >> --- /dev/null >> +++ b/Documentation/devicetree/bindings/mailbox/sunxi-msgbox.txt >> @@ -0,0 +1,40 @@ >> +Allwinner sunxi Message Box >> +=========================== >> + >> +The hardware message box on sunxi SoCs is a two-user mailbox controller >> +containing 8 unidirectional FIFOs bonded into 4 bidirectional mailbox channels. >> +An interrupt is raised for received messages, but software must poll to know >> +when a transmitted message has been acknowledged by the remote user. >> + >> +Refer to ./mailbox.txt for generic information about mailbox device-tree >> +bindings. >> + >> +Mailbox Device Node: >> +==================== >> + >> +Required properties: >> +-------------------- >> +- compatible: Must be "allwinner,sunxi-msgbox". > > The IP change quite often in the Allwinner SoCs, so it would be better > to use a more specific compatible there. IIRC that IP was introduced > with the A31, so what about sun6i-a31-msgbox? Ok, I will do this for v2, following Andre's suggestion. (I knew the AR100 was introduced with the A31, but I couldn't find any reference to the msgbox in the A31 manual). >> +- reg: Contains the mailbox register address range (base >> + address and length). >> +- clocks: phandle for the clock controller and specifier. >> +- clock-names: Must be "bus". >> +- resets: phandle for the reset controller and specifier. >> +- reset-names: Must be "bus". >> +- interrupts: Contains interrupt information for the mailbox. >> +- #mbox-cells Must be 2 - the indexes of the transmit and receive >> + channels, respectively. > > That would prevent any unidirectional communication, wouldn't it? > Other mailboxes driver seem to have two mbox channels, one for each > direction, which also seem to mimic our DMA bindings (where we are in > pretty much the same situation). I've responded to Jassi's comment about the same issue on patch 3. > Thanks! > Maxime Regards, Samuel -- 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
