xref: /openbmc/linux/Documentation/devicetree/bindings/powerpc/ibm,vas.txt (revision cf40a76e7d5874bb25f4404eecc58a2e033af885)
1*4dea2d1aSSukadev Bhattiprolu* IBM Powerpc Virtual Accelerator Switchboard (VAS)
2*4dea2d1aSSukadev Bhattiprolu
3*4dea2d1aSSukadev BhattiproluVAS is a hardware mechanism that allows kernel subsystems and user processes
4*4dea2d1aSSukadev Bhattiproluto directly submit compression and other requests to Nest accelerators (NX)
5*4dea2d1aSSukadev Bhattiproluor other coprocessors functions.
6*4dea2d1aSSukadev Bhattiprolu
7*4dea2d1aSSukadev BhattiproluRequired properties:
8*4dea2d1aSSukadev Bhattiprolu- compatible : should be "ibm,vas".
9*4dea2d1aSSukadev Bhattiprolu- ibm,vas-id : A unique identifier for each instance of VAS in the system
10*4dea2d1aSSukadev Bhattiprolu- reg : Should contain 4 pairs of 64-bit fields specifying the Hypervisor
11*4dea2d1aSSukadev Bhattiprolu  window context start and length, OS/User window context start and length,
12*4dea2d1aSSukadev Bhattiprolu  "Paste address" start and length, "Paste window id" start bit and number
13*4dea2d1aSSukadev Bhattiprolu  of bits)
14*4dea2d1aSSukadev Bhattiprolu
15*4dea2d1aSSukadev BhattiproluExample:
16*4dea2d1aSSukadev Bhattiprolu
17*4dea2d1aSSukadev Bhattiprolu	vas@6019100000000 {
18*4dea2d1aSSukadev Bhattiprolu		compatible = "ibm,vas", "ibm,power9-vas";
19*4dea2d1aSSukadev Bhattiprolu		reg = <0x6019100000000 0x2000000 0x6019000000000 0x100000000 0x8000000000000 0x100000000 0x20 0x10>;
20*4dea2d1aSSukadev Bhattiprolu		name = "vas";
21*4dea2d1aSSukadev Bhattiprolu		ibm,vas-id = <0x1>;
22*4dea2d1aSSukadev Bhattiprolu	};
23