18c2ecf20Sopenharmony_ci* IBM Powerpc Virtual Accelerator Switchboard (VAS)
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38c2ecf20Sopenharmony_ciVAS is a hardware mechanism that allows kernel subsystems and user processes
48c2ecf20Sopenharmony_cito directly submit compression and other requests to Nest accelerators (NX)
58c2ecf20Sopenharmony_cior other coprocessors functions.
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78c2ecf20Sopenharmony_ciRequired properties:
88c2ecf20Sopenharmony_ci- compatible : should be "ibm,vas".
98c2ecf20Sopenharmony_ci- ibm,vas-id : A unique identifier for each instance of VAS in the system
108c2ecf20Sopenharmony_ci- reg : Should contain 4 pairs of 64-bit fields specifying the Hypervisor
118c2ecf20Sopenharmony_ci  window context start and length, OS/User window context start and length,
128c2ecf20Sopenharmony_ci  "Paste address" start and length, "Paste window id" start bit and number
138c2ecf20Sopenharmony_ci  of bits)
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158c2ecf20Sopenharmony_ciExample:
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178c2ecf20Sopenharmony_ci	vas@6019100000000 {
188c2ecf20Sopenharmony_ci		compatible = "ibm,vas", "ibm,power9-vas";
198c2ecf20Sopenharmony_ci		reg = <0x6019100000000 0x2000000 0x6019000000000 0x100000000 0x8000000000000 0x100000000 0x20 0x10>;
208c2ecf20Sopenharmony_ci		name = "vas";
218c2ecf20Sopenharmony_ci		ibm,vas-id = <0x1>;
228c2ecf20Sopenharmony_ci	};
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