northbridge/via/cn700/acpi: Add the host bridge

Includes the DRAM controller device that knows which where the division
between addresses routed to the main memory and to the PCI bus is.

Change-Id: Id4cfeb8ff32de37723eee68a61c576e657dad30b
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Reviewed-on: https://review.coreboot.org/18896
Tested-by: build bot (Jenkins)
Reviewed-by: Martin Roth <martinroth@google.com>

1 files changed, 89 insertions, 0 deletions

diff --git a/src/northbridge/via/cn700/acpi/hostbridge.asl b/src/northbridge/via/cn700/acpi/hostbridge.asl
new file mode 100644
index 000000000000..2fb41588bbf1
--- /dev/null
+++ b/src/northbridge/via/cn700/acpi/hostbridge.asl
@@ -0,0 +1,89 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2017 Lubomir Rintel <lkundrak@v3.sk>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <arch/ioapic.h>
+
+Name (_HID, EisaId ("PNP0A03"))
+Name (_UID, 1)
+Name (_ADR, 0x00000000)
+Name (_BBN, 0)
+
+/* The DRAM controller */
+Device (MEMC)
+{
+	Name (_ADR, 0x00000003)
+
+	OperationRegion (MEMB, PCI_Config, 0x00, 0xEF)
+	Field (MEMB, DWordAcc, NoLock, Preserve) {
+
+		/* DRAM Rank Ending Address */
+		Offset (0x40),
+		R0EA, 8,	/* Rank 0 Ending Address */
+		R1EA, 8,	/* Rank 1 Ending Address */
+		R2EA, 8,	/* Rank 2 Ending Address */
+		R3EA, 8,	/* Rank 3 Ending Address */
+	}
+
+	/* Find the top of DRAM */
+	Method (TOLM, 0) {
+		/* Find the last occupied rank's end. */
+		Store (R3EA, Local0)
+		If (LEqual (Local0, Zero)) {
+			Store (R2EA, Local0)
+		}
+		If (LEqual (Local0, Zero)) {
+			Store (R1EA, Local0)
+		}
+		If (LEqual (Local0, Zero)) {
+			Store (R0EA, Local0)
+		}
+		/* The granularity is 64M */
+		ShiftLeft (Local0, 26, Local0)
+		Return (Local0)
+	}
+}
+
+Name (XCRS, ResourceTemplate () {
+	/* All PCI busses */
+	WordBusNumber (ResourceConsumer, MinNotFixed, MaxNotFixed, PosDecode,
+		0x0000, 0x0000, 0x00ff, 0x0000, 0x0100,,,)
+
+	/* IO-space, sans the PCI regs. */
+	WordIO (ResourceProducer, MinFixed, MaxFixed, PosDecode, EntireRange,
+		0x0000, 0x0000, 0x0CF7, 0x0000, 0x0CF8,
+		,,, TypeStatic)
+	WordIO (ResourceProducer, MinFixed, MaxFixed, PosDecode, EntireRange,
+		0x0000, 0x0D00, 0xFFFF, 0x0000, 0xF300,
+		,,, TypeStatic)
+
+	/* The space from top of DRAM to IOAPIC */
+	DWordMemory (ResourceProducer, PosDecode, MinFixed, MaxFixed, Cacheable, ReadWrite,
+		/* This is a template that gets filled in _CRS() */
+		0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000,,,
+		MEM0, AddressRangeMemory, TypeStatic)
+})
+Method (_CRS, 0) {
+
+	/* MEM0 is from the top of RAM to IOAPIC */
+	CreateDWordField (XCRS, \_SB.PCI0.MEM0._MIN, MEML)
+	CreateDWordField (XCRS, \_SB.PCI0.MEM0._MAX, MEMH)
+	CreateDWordField (XCRS, \_SB.PCI0.MEM0._LEN, LENM)
+	Store (\_SB.PCI0.MEMC.TOLM, MEML)
+	Subtract (IO_APIC_ADDR, 1, MEMH)
+	Subtract (IO_APIC_ADDR, MEML, LENM)
+
+	Return (XCRS);
+}