Tom Rini | 53633a8 | 2024-02-29 12:33:36 -0500 | [diff] [blame] | 1 | ====================================================================== |
| 2 | Device tree bindings for Aspeed AST2400/AST2500 PCI-to-AHB Bridge Control Driver |
| 3 | ====================================================================== |
| 4 | |
| 5 | The bridge is available on platforms with the VGA enabled on the Aspeed device. |
| 6 | In this case, the host has access to a 64KiB window into all of the BMC's |
| 7 | memory. The BMC can disable this bridge. If the bridge is enabled, the host |
| 8 | has read access to all the regions of memory, however the host only has read |
| 9 | and write access depending on a register controlled by the BMC. |
| 10 | |
| 11 | Required properties: |
| 12 | =================== |
| 13 | |
| 14 | - compatible: must be one of: |
| 15 | - "aspeed,ast2400-p2a-ctrl" |
| 16 | - "aspeed,ast2500-p2a-ctrl" |
| 17 | |
| 18 | Optional 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 | |
| 25 | The p2a-control node should be the child of a syscon node with the required |
| 26 | property: |
| 27 | |
| 28 | - compatible : Should be one of the following: |
| 29 | "aspeed,ast2400-scu", "syscon", "simple-mfd" |
| 30 | "aspeed,ast2500-scu", "syscon", "simple-mfd" |
| 31 | |
| 32 | Example |
| 33 | =================== |
| 34 | |
| 35 | g4 Example |
| 36 | ---------- |
| 37 | |
| 38 | syscon: 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 | }; |