Platform/RPi4: Add ACPI entry for Genet network interface

The Raspberry Pi 4 platforms uses a Broadcom Genet network interface, for
which we need ACPI entries in order to make it usable under Linux.

This patch adds these entries, including a max-dma-burst-size DSD attribute
aimed at simplifying support for Genet on distros that use older kernels,
such as Debian.

Note that we ran these settings through someone working for Broadcom, who
okayed the proposed values including ownership of max-dma-burst-size (which
we expect to also require for Device Tree usage on older kernels, hence the
requirement for a designated owner).

Signed-off-by: Pete Batard <pete@akeo.ie>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>

Platform/RaspberryPi/RPi4/AcpiTables/Dsdt.asl

@@ -267,6 +267,35 @@ DefinitionBlock ("Dsdt.aml", "DSDT", 5, "MSFT", "EDK2", 2)
       }
     }
 
+    Device (ETH0)
+    {
+      Name (_HID, "BCM6E4E")
+      Name (_CID, "BCM6E4E")
+      Name (_UID, 0x0)
+      Name (_CCA, 0x0)
+      Method (_STA)
+      {
+        Return (0xf)
+      }
+      Method (_CRS, 0x0, Serialized)
+      {
+        Name (RBUF, ResourceTemplate ()
+        {
+          Memory32Fixed (ReadWrite, 0xfd580000, 0x10000, )
+          Interrupt (ResourceConsumer, Level, ActiveHigh, Exclusive) { 0xBD }
+          Interrupt (ResourceConsumer, Level, ActiveHigh, Exclusive) { 0xBE }
+        })
+        Return (RBUF)
+      }
+      Name (_DSD, Package () {
+        ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
+        Package () {
+          Package () { "brcm,max-dma-burst-size", 0x08 },
+          Package () { "phy-mode", "rgmii" },
+        }
+      })
+    }
+
     // Description: I2C
     Device (I2C1)
     {