x86: baytrail: Add platform ASL files

This adds basic BayTrail platform ASL files. They are intended to be
included in dsdt.asl of any board that is based on this platform.

Note: ACPI mode support for GPIO/LPSS/SCC/LPE are not supported for
now. They will be added in the future.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/x86/include/asm/arch-baytrail/acpi/irqroute.asl b/arch/x86/include/asm/arch-baytrail/acpi/irqroute.asl
new file mode 100644
index 0000000..64d3820
--- /dev/null
+++ b/arch/x86/include/asm/arch-baytrail/acpi/irqroute.asl
@@ -0,0 +1,48 @@
+/*
+ * Copyright (C) 2007-2009 coresystems GmbH
+ * Copyright (C) 2013 Google Inc.
+ * Copyright (C) 2016 Bin Meng <bmeng.cn@gmail.com>
+ *
+ * Modified from coreboot src/soc/intel/baytrail/acpi/irqroute.asl
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+Name(\PICM, 0)
+
+/*
+ * The _PIC method is called by the OS to choose between interrupt
+ * routing via the i8259 interrupt controller or the APIC.
+ *
+ * _PIC is called with a parameter of 0 for i8259 configuration and
+ * with a parameter of 1 for Local APIC/IOAPIC configuration.
+ */
+Method(\_PIC, 1)
+{
+	/* Remember the OS' IRQ routing choice */
+	Store(Arg0, PICM)
+}
+
+/* PCI interrupt routing */
+Method(_PRT) {
+	If (PICM) {
+		Return (Package() {
+			#undef PIC_MODE
+			#include "irq_helper.h"
+			PCI_DEV_PIRQ_ROUTES
+		})
+	} Else {
+		Return (Package() {
+			#define PIC_MODE
+			#include "irq_helper.h"
+			PCI_DEV_PIRQ_ROUTES
+		})
+	}
+
+}
+
+/* PCIe downstream ports interrupt routing */
+PCIE_BRIDGE_IRQ_ROUTES
+#undef PIC_MODE
+#include "irq_helper.h"
+PCIE_BRIDGE_IRQ_ROUTES