xref: /freebsd/sys/contrib/device-tree/Bindings/rng/timeriomem_rng.txt (revision c66ec88fed842fbaad62c30d510644ceb7bd2d71)
1*c66ec88fSEmmanuel VadotHWRNG support for the timeriomem_rng driver
2*c66ec88fSEmmanuel Vadot
3*c66ec88fSEmmanuel VadotRequired properties:
4*c66ec88fSEmmanuel Vadot- compatible : "timeriomem_rng"
5*c66ec88fSEmmanuel Vadot- reg : base address to sample from
6*c66ec88fSEmmanuel Vadot- period : wait time in microseconds to use between samples
7*c66ec88fSEmmanuel Vadot
8*c66ec88fSEmmanuel VadotOptional properties:
9*c66ec88fSEmmanuel Vadot- quality : estimated number of bits of true entropy per 1024 bits read from the
10*c66ec88fSEmmanuel Vadot            rng.  Defaults to zero which causes the kernel's default quality to
11*c66ec88fSEmmanuel Vadot            be used instead.  Note that the default quality is usually zero
12*c66ec88fSEmmanuel Vadot            which disables using this rng to automatically fill the kernel's
13*c66ec88fSEmmanuel Vadot            entropy pool.
14*c66ec88fSEmmanuel Vadot
15*c66ec88fSEmmanuel VadotN.B. currently 'reg' must be at least four bytes wide and 32-bit aligned
16*c66ec88fSEmmanuel Vadot
17*c66ec88fSEmmanuel VadotExample:
18*c66ec88fSEmmanuel Vadot
19*c66ec88fSEmmanuel Vadothwrng@44 {
20*c66ec88fSEmmanuel Vadot	#address-cells = <1>;
21*c66ec88fSEmmanuel Vadot	#size-cells = <1>;
22*c66ec88fSEmmanuel Vadot	compatible = "timeriomem_rng";
23*c66ec88fSEmmanuel Vadot	reg = <0x44 0x04>;
24*c66ec88fSEmmanuel Vadot	period = <1000000>;
25*c66ec88fSEmmanuel Vadot};
26