soc/apollolake/acpi: Fill in ACPI MADT table

ACPI MADT tables required to describe the multiprocessor interrupt 
routing. Apollolake SOC also have the interrupt override table like
other x86 silicons.

Change-Id: I85976e227963c950aad4476d68581b96e1090559
Signed-off-by: Lance Zhao <lijian.zhao@intel.com>
Reviewed-on: https://review.coreboot.org/13373
Tested-by: build bot (Jenkins)
Reviewed-by: Aaron Durbin <adurbin@chromium.org>

src/soc/intel/apollolake/acpi.c

@@ -11,6 +11,8 @@
  */
 
 #include <arch/acpi.h>
+#include <arch/ioapic.h>
+#include <arch/smp/mpspec.h>
 #include <cpu/x86/smm.h>
 #include <soc/acpi.h>
 #include <soc/iomap.h>
@@ -25,17 +27,38 @@ unsigned long acpi_fill_mcfg(unsigned long current)
 	return current;
 }
 
-unsigned long acpi_fill_madt(unsigned long current)
-{
-	return current;
-}
-
 static int acpi_sci_irq(void)
 {
 	int sci_irq = 9;
 	return sci_irq;
 }
 
+static unsigned long acpi_madt_irq_overrides(unsigned long current)
+{
+	int sci = acpi_sci_irq();
+	uint16_t flags = MP_IRQ_TRIGGER_LEVEL | MP_IRQ_POLARITY_LOW;;
+
+	/* INT_SRC_OVR */
+	current += acpi_create_madt_irqoverride((void *)current, 0, 0, 2, 0);
+
+	/* SCI */
+	current += acpi_create_madt_irqoverride((void *)current, 0, sci, sci, flags);
+
+	return current;
+}
+
+unsigned long acpi_fill_madt(unsigned long current)
+{
+	/* Local APICs */
+	current = acpi_create_madt_lapics(current);
+
+	/* IOAPIC */
+	current += acpi_create_madt_ioapic((void *) current,
+					     2, IO_APIC_ADDR, 0);
+
+	return acpi_madt_irq_overrides(current);
+}
+
 void soc_fill_common_fadt(acpi_fadt_t * fadt)
 {
 	const uint16_t pmbase = ACPI_PMIO_BASE;