1====================================================================== 2Device tree bindings for Aspeed AST2400/AST2500 PCI-to-AHB Bridge Control Driver 3====================================================================== 4 5The bridge is available on platforms with the VGA enabled on the Aspeed device. 6In this case, the host has access to a 64KiB window into all of the BMC's 7memory. The BMC can disable this bridge. If the bridge is enabled, the host 8has read access to all the regions of memory, however the host only has read 9and write access depending on a register controlled by the BMC. 10 11Required properties: 12=================== 13 14 - compatible: must be one of: 15 - "aspeed,ast2400-p2a-ctrl" 16 - "aspeed,ast2500-p2a-ctrl" 17 18Optional properties: 19=================== 20 21- reg: A hint for the memory regions associated with the P2A controller 22- memory-region: A phandle to a reserved_memory region to be used for the PCI 23 to AHB mapping 24 25The p2a-control node should be the child of a syscon node with the required 26property: 27 28- compatible : Should be one of the following: 29 "aspeed,ast2400-scu", "syscon", "simple-mfd" 30 "aspeed,ast2500-scu", "syscon", "simple-mfd" 31 32Example 33=================== 34 35g4 Example 36---------- 37 38syscon: scu@1e6e2000 { 39 compatible = "aspeed,ast2400-scu", "syscon", "simple-mfd"; 40 reg = <0x1e6e2000 0x1a8>; 41 42 p2a: p2a-control { 43 compatible = "aspeed,ast2400-p2a-ctrl"; 44 memory-region = <&reserved_memory>; 45 }; 46}; 47