On Tue, Jun 13, 2017 at 02:38:26PM +0000, Gabriele Paoloni wrote:

quoted

Is there an example ASL showing how these LPC devices are
currently presented in ACPI?

Please find below the asl sketch for our LPC and IPMI

//
// LPC
//

Scope(_SB) {
  Device (LPC0) {
    Name (_HID, "HISI0191")  // HiSi LPC
    Name (_CRS, ResourceTemplate () {
      Memory32Fixed (ReadWrite, 0xa01b0000, 0x1000)
    })
  }

  Device (LPC0.IPMI) {
    Name (_HID, "IPI0001")
    Method (_IFT) {
      Return (0x03)
    }
    Name (LORS, ResourceTemplate() {
      QWordIO (
        ResourceConsumer,
	MinNotFixed,     // _MIF
	MaxNotFixed,     // _MAF
	PosDecode,
	EntireRange,
	0x0,             // _GRA
	0xe4,            // _MIN
	0x3fff,          // _MAX
	0x0,             // _TRA
	0x04,            // _LEN
	, ,
	BTIO
      )
    })
    CreateQWordField (LORS, BTIO._MIN, CMIN)
    CreateQWordField (LORS, BTIO._MAX, CMAX)
    CreateQWordField (LORS, BTIO._LEN, CLEN)

    Method (_PRS, 0) {
      Return (LORS)
    }

    Method (_CRS, 0) {
      Return (LORS)
    }
    Method (_SRS, 1) {
      CreateQWordField (Arg0, \_SB.LPC0.IPMI.BTIO._MIN, IMIN)
      Store (IMIN, CMIN)
      CreateQWordField (Arg0, \_SB.LPC0.IPMI.BTIO._MAX, IMAX)
      Store (IMAX, CMAX)
    }
  } 
[...]
}

Thanks. So this looks pretty much like normal Linux MFD device which we
already have support for adding ACPI bindings to child devices. It
should also support splitting resources to child devices IIRC.