The APM X-Gene SLIMpro mailbox is used to communicate messages between the ARM64 processors and the Cortex M3 (dubbed SLIMpro). It uses a simple interrupt based door bell mechanism and can exchange simple messages using the internal registers. There are total of 8 interrupts in this mailbox. Each used for an individual door bell (or mailbox channel). Required properties: - compatible: Should be as "apm,xgene-slimpro-mbox". - reg: Contains the mailbox register address range. - interrupts: 8 interrupts must be from 0 to 7, interrupt 0 define the the interrupt for mailbox channel 0 and interrupt 1 for mailbox channel 1 and so likewise for the reminder. - #mbox-cells: only one to specify the mailbox channel number. Example: Mailbox Node: mailbox: mailbox@10540000 { compatible = "apm,xgene-slimpro-mbox"; reg = <0x0 0x10540000 0x0 0xa000>; #mbox-cells = <1>; interrupts = <0x0 0x0 0x4>, <0x0 0x1 0x4>, <0x0 0x2 0x4>, <0x0 0x3 0x4>, <0x0 0x4 0x4>, <0x0 0x5 0x4>, <0x0 0x6 0x4>, <0x0 0x7 0x4>, };