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- memory-region: A phandle to a reserved_memory region to be used for the PCI 22 to AHB mapping 23 24The p2a-control node should be the child of a syscon node with the required 25property: 26 27- compatible : Should be one of the following: 28 "aspeed,ast2400-scu", "syscon", "simple-mfd" 29 "aspeed,g4-scu", "syscon", "simple-mfd" 30 "aspeed,ast2500-scu", "syscon", "simple-mfd" 31 "aspeed,g5-scu", "syscon", "simple-mfd" 32 33Example 34=================== 35 36g4 Example 37---------- 38 39syscon: scu@1e6e2000 { 40 compatible = "aspeed,ast2400-scu", "syscon", "simple-mfd"; 41 reg = <0x1e6e2000 0x1a8>; 42 43 p2a: p2a-control { 44 compatible = "aspeed,ast2400-p2a-ctrl"; 45 memory-region = <&reserved_memory>; 46 }; 47}; 48