From: Tomas Hruby <tom@minix3.org>
Date: Tue, 7 Sep 2010 07:18:11 +0000 (+0000)
Subject: APIC mode uses IO APICs
X-Git-Tag: v3.1.8~12
X-Git-Url: http://zhaoyanbai.com/repos/icons/debian/static/datamaps.china.min.js?a=commitdiff_plain;h=e6ebac015dfcec24998eea8c467bd8e2f0971067;p=minix.git

APIC mode uses IO APICs

- kernel turns on IO APICs if no_apic is _not_ set or is equal 0

- pci driver must use the acpi driver to setup IRQ routing otherwise
  the system cannot work correctly except systems like KVM that use
  only legacy (E)ISA IRQs 0-15
---

diff --git a/drivers/acpi/acpi.c b/drivers/acpi/acpi.c
index 8581e1786..bac095b60 100644
--- a/drivers/acpi/acpi.c
+++ b/drivers/acpi/acpi.c
@@ -12,6 +12,7 @@ PUBLIC struct machine machine;
 #define IRQ_TABLE_ENTRIES	(PCI_MAX_DEVICES * PCI_MAX_PINS)
 
 PRIVATE int irqtable[IRQ_TABLE_ENTRIES];
+PRIVATE ACPI_HANDLE pci_root_handle; 
 
 /* don't know where ACPI tables are, we may need to access any memory */
 PRIVATE int init_mem_priv(void)
@@ -93,7 +94,7 @@ PRIVATE ACPI_STATUS get_irq_resource(ACPI_RESOURCE *res, void *context)
 		irq = &res->Data.Irq;
 		add_irq(tbl->Address >> 16, tbl->Pin,
 				irq->Interrupts[tbl->SourceIndex]);
-	} if (res->Type == ACPI_RESOURCE_TYPE_EXTENDED_IRQ) {
+	} else if (res->Type == ACPI_RESOURCE_TYPE_EXTENDED_IRQ) {
 		ACPI_RESOURCE_EXTENDED_IRQ *irq;
 		
 		add_irq(tbl->Address >> 16, tbl->Pin,
@@ -103,32 +104,18 @@ PRIVATE ACPI_STATUS get_irq_resource(ACPI_RESOURCE *res, void *context)
 	return AE_OK;
 }
 
-PRIVATE ACPI_STATUS add_pci_dev(ACPI_HANDLE handle,
-				UINT32 level,
-				void *context,
-				void **retval)
+PRIVATE ACPI_STATUS get_pci_irq_routing(ACPI_HANDLE handle)
 {
 	ACPI_STATUS status;
 	ACPI_BUFFER abuff;
 	char buff[4096];
 	ACPI_PCI_ROUTING_TABLE *tbl;
-	int i;
-	static unsigned called;
 
-	if (++called > 1) {
-		printf("ACPI: Warning! Multi rooted PCI is not supported!\n");
-		return AE_OK;
-	}
-	
 	abuff.Length = sizeof(buff);
 	abuff.Pointer = buff;
 
-	for (i = 0; i < IRQ_TABLE_ENTRIES; i++)
-		irqtable[i] = -1;
-
 	status = AcpiGetIrqRoutingTable(handle, &abuff);
 	if (ACPI_FAILURE(status)) {
-		printf("ACPI: ACPI no routing table\n");
 		return AE_OK;
 	}
 
@@ -154,15 +141,51 @@ PRIVATE ACPI_STATUS add_pci_dev(ACPI_HANDLE handle,
 			continue;
 		}
 	}
-
+	
 	return AE_OK;
 }
 
+PRIVATE ACPI_STATUS add_pci_root_dev(ACPI_HANDLE handle,
+				UINT32 level,
+				void *context,
+				void **retval)
+{
+	int i;
+	static unsigned called;
+
+	if (++called > 1) {
+		printf("ACPI: Warning! Multi rooted PCI is not supported!\n");
+		return AE_OK;
+	}
+
+	for (i = 0; i < IRQ_TABLE_ENTRIES; i++)
+		irqtable[i] = -1;
+
+	return get_pci_irq_routing(handle);
+}
+
+PRIVATE ACPI_STATUS add_pci_dev(ACPI_HANDLE handle,
+				UINT32 level,
+				void *context,
+				void **retval)
+{
+	/* skip pci root when we get to it again */
+	if (handle == pci_root_handle)
+		return AE_OK;
+
+	return get_pci_irq_routing(handle);
+}
+
 PRIVATE void scan_devices(void)
 {
 	ACPI_STATUS(status);
+	
+	/* get the root first */
+	status = AcpiGetDevices("PNP0A03", add_pci_root_dev, NULL, NULL);
+	assert(ACPI_SUCCESS(status));
 
-	status = AcpiGetDevices("PNP0A03", add_pci_dev, NULL, NULL);
+	/* get the rest of the devices that implement _PRT */
+	status = AcpiGetDevices(NULL, add_pci_dev, NULL, NULL);
 	assert(ACPI_SUCCESS(status));
 }
 PRIVATE ACPI_STATUS init_acpica(void)
diff --git a/drivers/acpi/osminixxf.c b/drivers/acpi/osminixxf.c
index 4d55acd1a..97e6d54d8 100644
--- a/drivers/acpi/osminixxf.c
+++ b/drivers/acpi/osminixxf.c
@@ -883,7 +883,9 @@ AcpiOsReadMemory (
     UINT32                  *Value,
     UINT32                  Width)
 {
-	panic("NOTIMPLEMENTED %s\n", __func__);
+	/* FIXME this operation is ignored */
+	*Value = 0;
+
 	return (AE_OK);
 }
 
@@ -908,7 +910,7 @@ AcpiOsWriteMemory (
     UINT32                  Value,
     UINT32                  Width)
 {
-	panic("NOTIMPLEMENTED %s\n", __func__);
+	/* FIXME this operation is ignored */
 	return (AE_OK);
 }
 
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index c75198972..e64e91edd 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -962,10 +962,10 @@ PRIVATE int acpi_get_irq(unsigned dev, unsigned pin)
 
 PRIVATE int derive_irq(struct pcidev * dev, int pin)
 {
-	struct pcidev * parent_brige;
+	struct pcidev * parent_bridge;
 	int slot;
 	
-	parent_brige = &pcidev[pcibus[get_busind(dev->pd_busnr)].pb_devind];
+	parent_bridge = &pcidev[pcibus[get_busind(dev->pd_busnr)].pb_devind];
 
 	/*
 	 * We don't support PCI-Express, no ARI, decode the slot of the device
@@ -973,7 +973,7 @@ PRIVATE int derive_irq(struct pcidev * dev, int pin)
 	 */
 	slot = ((dev->pd_func) >> 3) & 0x1f;
 
-	return acpi_get_irq(parent_brige->pd_dev, (pin + slot) % 4);
+	return acpi_get_irq(parent_bridge->pd_dev, (pin + slot) % 4);
 }
 
 /*===========================================================================*
@@ -998,15 +998,16 @@ int devind;
 		if (irq >= 0) {
 			ilr = irq;
 			pci_attr_w8(devind, PCI_ILR, ilr);
-			printf("PCI: ACPI IRQ %d for "
-					"device %d.%d.%d INT%c\n",
-					irq,
-					pcidev[devind].pd_busnr,
-					pcidev[devind].pd_dev,
-					pcidev[devind].pd_func,
-					'A' + ipr-1);
+			if (debug)
+				printf("PCI: ACPI IRQ %d for "
+						"device %d.%d.%d INT%c\n",
+						irq,
+						pcidev[devind].pd_busnr,
+						pcidev[devind].pd_dev,
+						pcidev[devind].pd_func,
+						'A' + ipr-1);
 		}
-		else {
+		else if (debug) {
 			printf("PCI: no ACPI IRQ routing for "
 					"device %d.%d.%d INT%c\n",
 					pcidev[devind].pd_busnr,
diff --git a/kernel/Makefile b/kernel/Makefile
index 4a3d3160f..6a4cf359d 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -23,8 +23,8 @@ DPADD+=	${LIBC}
 LDADD+=	-lc
 .endif
 
-CPPFLAGS+=	-I${.CURDIR}/arch/${ARCH}/include -I${MINIXSRCDIR}
-AFLAGS+=	-I${.CURDIR}/arch/${ARCH}/include -I${MINIXSRCDIR}
+CPPFLAGS+=	-I${.CURDIR} -I${.CURDIR}/arch/${ARCH}/include -I${MINIXSRCDIR}
+AFLAGS+=	-I${.CURDIR} -I${.CURDIR}/arch/${ARCH}/include -I${MINIXSRCDIR}
 
 INSTALLFLAGS+=	-S 0
 BINDIR=	/usr/sbin
diff --git a/kernel/arch/i386/acpi.c b/kernel/arch/i386/acpi.c
index a3342214c..159f15b98 100644
--- a/kernel/arch/i386/acpi.c
+++ b/kernel/arch/i386/acpi.c
@@ -1,83 +1,5 @@
 #include "kernel/kernel.h"
-
-/* ACPI root system description pointer */
-struct acpi_rsdp {
-	char	signature[8]; /* must be "RSD PTR " */
-	u8_t	checksum;
-	char	oemid[6];
-	u8_t	revision;
-	u32_t	rsdt_addr;
-	u32_t	length;
-}; 
-
-#define ACPI_SDT_SIGNATURE_LEN	4
-
-#define ACPI_SDT_SIGNATURE(name)	#name
-
-/* header common to all system description tables */
-struct acpi_sdt_header {
-	char	signature[ACPI_SDT_SIGNATURE_LEN];
-	u32_t	length;
-	u8_t	revision;
-	u8_t	checksum;
-	char	oemid[6];
-	char	oem_table_id[8];
-	u32_t	oem_revision;
-	u32_t	creator_id;
-	u32_t	creator_revision;
-};
-
-struct acpi_madt_hdr {
-	struct acpi_sdt_header	hdr;
-	u32_t			local_apic_address;
-	u32_t			flags;
-};
-
-#define ACPI_MADT_TYPE_LAPIC		0
-#define ACPI_MADT_TYPE_IOAPIC		1
-#define ACPI_MADT_TYPE_INT_SRC		2
-#define ACPI_MADT_TYPE_NMI_SRC		3
-#define ACPI_MADT_TYPE_LAPIC_NMI	4
-#define ACPI_MADT_TYPE_LAPIC_ADRESS	5
-#define ACPI_MADT_TYPE_IOSAPIC		6
-#define ACPI_MADT_TYPE_LSAPIC		7
-#define ACPI_MADT_TYPE_PLATFORM_INT_SRC	8
-#define ACPI_MADT_TYPE_Lx2APIC		9
-#define ACPI_MADT_TYPE_Lx2APIC_NMI	10
-
-struct acpi_madt_item_hdr{
-	u8_t	type;
-	u8_t	length;
-};
-
-struct acpi_madt_lapic {
-	struct acpi_madt_item_hdr hdr;
-	u8_t	acpi_cpu_id;
-	u8_t	apic_id;
-	u32_t	flags;
-};
-
-struct acpi_madt_ioapic {
-	struct acpi_madt_item_hdr hdr;
-	u8_t	id;
-	u8_t	__reserved;
-	u32_t	address;
-	u32_t	global_int_base;
-};
-
-struct acpi_madt_int_src {
-	struct acpi_madt_item_hdr hdr;
-	u8_t	bus;
-	u8_t	bus_int;
-	u32_t	global_int;
-	u16_t	mps_flags;
-};
-
-struct acpi_madt_nmi {
-	struct acpi_madt_item_hdr hdr;
-	u16_t	flags;
-	u32_t	global_int;
-};
+#include "acpi.h"
 
 typedef int ((* acpi_read_t)(phys_bytes addr, void * buff, size_t size));
 
@@ -299,3 +221,25 @@ PUBLIC void acpi_init(void)
 		sdt_trans[i].length = hdr.length;
 	}
 }
+
+PUBLIC struct acpi_madt_ioapic * acpi_get_ioapic_next(void)
+{
+	static unsigned idx = 0;
+	static struct acpi_madt_hdr * madt_hdr;
+
+	struct acpi_madt_ioapic * ret;
+
+	if (idx == 0) {
+		madt_hdr = (struct acpi_madt_hdr *)
+			phys2vir(acpi_get_table_base("APIC"));
+		if (madt_hdr == NULL)
+			return NULL;
+	}
+
+	ret = (struct acpi_madt_ioapic *)
+		acpi_madt_get_typed_item(madt_hdr, ACPI_MADT_TYPE_IOAPIC, idx);
+	if (ret)
+		idx++;
+
+	return ret;
+}
diff --git a/kernel/arch/i386/acpi.h b/kernel/arch/i386/acpi.h
index c273ac4ec..e2cf35217 100644
--- a/kernel/arch/i386/acpi.h
+++ b/kernel/arch/i386/acpi.h
@@ -3,6 +3,92 @@
 
 #include "kernel/kernel.h"
 
+/* ACPI root system description pointer */
+struct acpi_rsdp {
+	char	signature[8]; /* must be "RSD PTR " */
+	u8_t	checksum;
+	char	oemid[6];
+	u8_t	revision;
+	u32_t	rsdt_addr;
+	u32_t	length;
+}; 
+
+#define ACPI_SDT_SIGNATURE_LEN	4
+
+#define ACPI_SDT_SIGNATURE(name)	#name
+
+/* header common to all system description tables */
+struct acpi_sdt_header {
+	char	signature[ACPI_SDT_SIGNATURE_LEN];
+	u32_t	length;
+	u8_t	revision;
+	u8_t	checksum;
+	char	oemid[6];
+	char	oem_table_id[8];
+	u32_t	oem_revision;
+	u32_t	creator_id;
+	u32_t	creator_revision;
+};
+
+struct acpi_madt_hdr {
+	struct acpi_sdt_header	hdr;
+	u32_t			local_apic_address;
+	u32_t			flags;
+};
+
+#define ACPI_MADT_TYPE_LAPIC		0
+#define ACPI_MADT_TYPE_IOAPIC		1
+#define ACPI_MADT_TYPE_INT_SRC		2
+#define ACPI_MADT_TYPE_NMI_SRC		3
+#define ACPI_MADT_TYPE_LAPIC_NMI	4
+#define ACPI_MADT_TYPE_LAPIC_ADRESS	5
+#define ACPI_MADT_TYPE_IOSAPIC		6
+#define ACPI_MADT_TYPE_LSAPIC		7
+#define ACPI_MADT_TYPE_PLATFORM_INT_SRC	8
+#define ACPI_MADT_TYPE_Lx2APIC		9
+#define ACPI_MADT_TYPE_Lx2APIC_NMI	10
+
+struct acpi_madt_item_hdr{
+	u8_t	type;
+	u8_t	length;
+};
+
+struct acpi_madt_lapic {
+	struct acpi_madt_item_hdr hdr;
+	u8_t	acpi_cpu_id;
+	u8_t	apic_id;
+	u32_t	flags;
+};
+
+struct acpi_madt_ioapic {
+	struct acpi_madt_item_hdr hdr;
+	u8_t	id;
+	u8_t	__reserved;
+	u32_t	address;
+	u32_t	global_int_base;
+};
+
+struct acpi_madt_int_src {
+	struct acpi_madt_item_hdr hdr;
+	u8_t	bus;
+	u8_t	bus_int;
+	u32_t	global_int;
+	u16_t	mps_flags;
+};
+
+struct acpi_madt_nmi {
+	struct acpi_madt_item_hdr hdr;
+	u16_t	flags;
+	u32_t	global_int;
+};
+
 _PROTOTYPE(void acpi_init, (void));
 
+/* 
+ * Returns a pointer to the io acpi structure in the MADT table in ACPI. The
+ * pointer is valid only until paging is turned off. No memory is allocated in
+ * this function thus no memory needs to be freed
+ */
+_PROTOTYPE(struct acpi_madt_ioapic * acpi_get_ioapic_next, (void));
+
 #endif /* __ACPI_H__ */
diff --git a/kernel/arch/i386/apic.c b/kernel/arch/i386/apic.c
index 4b0804cfe..54680df30 100644
--- a/kernel/arch/i386/apic.c
+++ b/kernel/arch/i386/apic.c
@@ -2,11 +2,13 @@
  * APIC handling routines. APIC is a requirement for SMP
  */
 #include "kernel/kernel.h"
+#include <assert.h>
 
 #include <unistd.h>
 #include <minix/portio.h>
 
 #include <minix/syslib.h>
+#include <machine/cmos.h>
 
 #include "kernel/proc.h"
 #include "kernel/glo.h"
@@ -18,25 +20,111 @@
 #include "apic_asm.h"
 #include "kernel/clock.h"
 #include "glo.h"
+#include "hw_intr.h"
+
+#include "acpi.h"
 
 #ifdef CONFIG_WATCHDOG
 #include "kernel/watchdog.h"
 #endif
 
+#define APIC_ENABLE		0x100
+#define APIC_FOCUS_DISABLED	(1 << 9)
+#define APIC_SIV		0xFF
+
+#define APIC_TDCR_2	0x00
+#define APIC_TDCR_4	0x01
+#define APIC_TDCR_8	0x02
+#define APIC_TDCR_16	0x03
+#define APIC_TDCR_32	0x08
+#define APIC_TDCR_64	0x09
+#define APIC_TDCR_128	0x0a
+#define APIC_TDCR_1	0x0b
+
+#define IS_SET(mask)		(mask)
+#define IS_CLEAR(mask)		0
+
+#define APIC_LVTT_VECTOR_MASK	0x000000FF
+#define APIC_LVTT_DS_PENDING	(1 << 12)
+#define APIC_LVTT_MASK		(1 << 16)
+#define APIC_LVTT_TM		(1 << 17)
+
+#define APIC_LVT_IIPP_MASK	0x00002000
+#define APIC_LVT_IIPP_AH	0x00002000
+#define APIC_LVT_IIPP_AL	0x00000000
+
+#define APIC_LVT_TM_ONESHOT	IS_CLEAR(APIC_LVTT_TM)
+#define APIC_LVT_TM_PERIODIC	IS_SET(APIC_LVTT_TM)
+
+#define IOAPIC_REGSEL		0x0
+#define IOAPIC_RW		0x10
+
+#define APIC_ICR_DM_MASK		0x00000700
+#define APIC_ICR_VECTOR			APIC_LVTT_VECTOR_MASK
+#define APIC_ICR_DM_FIXED		(0 << 8)
+#define APIC_ICR_DM_LOWEST_PRIORITY	(1 << 8)
+#define APIC_ICR_DM_SMI			(2 << 8)
+#define APIC_ICR_DM_RESERVED		(3 << 8)
+#define APIC_ICR_DM_NMI			(4 << 8)
+#define APIC_ICR_DM_INIT		(5 << 8)
+#define APIC_ICR_DM_STARTUP		(6 << 8)
+#define APIC_ICR_DM_EXTINT		(7 << 8)
+
+#define APIC_ICR_DM_PHYSICAL		(0 << 11)
+#define APIC_ICR_DM_LOGICAL		(1 << 11)
+
+#define APIC_ICR_DELIVERY_PENDING	(1 << 12)
+
+#define APIC_ICR_INT_POLARITY		(1 << 13)
+#define APIC_ICR_INTPOL_LOW		IS_SET(APIC_ICR_INT_POLARITY)
+#define APIC_ICR_INTPOL_HIGH		IS_CLEAR(APIC_ICR_INT_POLARITY)
+
+#define APIC_ICR_LEVEL_ASSERT		(1 << 14)
+#define APIC_ICR_LEVEL_DEASSERT		(0 << 14)
+
+#define APIC_ICR_TRIGGER		(1 << 15)
+#define APIC_ICR_TM_LEVEL		IS_CLEAR(APIC_ICR_TRIGGER)
+#define APIC_ICR_TM_EDGE		IS_CLEAR(APIC_ICR_TRIGGER)
+
+#define APIC_ICR_INT_MASK		(1 << 16)
+
+#define APIC_ICR_DEST_FIELD		(0 << 18)
+#define APIC_ICR_DEST_SELF		(1 << 18)
+#define APIC_ICR_DEST_ALL		(2 << 18)
+#define APIC_ICR_DEST_ALL_BUT_SELF	(3 << 18)
+
 #define IA32_APIC_BASE	0x1b
 #define IA32_APIC_BASE_ENABLE_BIT	11
 
+/* FIXME we should spread the irqs across as many priority levels as possible
+ * due to buggy hw */
+#define LAPIC_VECTOR(irq)	(IRQ0_VECTOR +(irq))
+
+#define IOAPIC_IRQ_STATE_MASKED 0x1
+
 /* currently only 2 interrupt priority levels are used */
 #define SPL0				0x0
 #define	SPLHI				0xF
 
-/*
- * to make APIC work if SMP is not configured, we need to set the maximal number
- * of CPUS to 1, cpuid to return 0 and the current cpu is always BSP
- */
-#define CONFIG_MAX_CPUS 1
 #define cpu_is_bsp(x) 1
 
+PUBLIC struct io_apic io_apic[MAX_NR_IOAPICS];
+PUBLIC unsigned nioapics;
+
+struct irq;
+typedef void (* eoi_method_t)(struct irq *);
+
+struct irq {
+	struct io_apic * 	ioa;
+	unsigned		pin;
+	unsigned		vector;
+	eoi_method_t		eoi;
+	unsigned		state;
+};
+
+PRIVATE struct irq io_apic_irq[NR_IRQ_VECTORS];
+
+
 #define lapic_write_icr1(val)	lapic_write(LAPIC_ICR1, val)
 #define lapic_write_icr2(val)	lapic_write(LAPIC_ICR2, val)
 
@@ -45,23 +133,20 @@
 
 #define VERBOSE_APIC(x) x
 
-PRIVATE int ioapic_enabled;
-PRIVATE u32_t ioapic_id_mask[8];
+PUBLIC int ioapic_enabled;
 PUBLIC u32_t lapic_addr_vaddr;
 PUBLIC vir_bytes lapic_addr;
 PUBLIC vir_bytes lapic_eoi_addr;
 
-PRIVATE volatile int probe_ticks;
+PRIVATE volatile unsigned probe_ticks;
 PRIVATE	u64_t tsc0, tsc1;
 PRIVATE	u32_t lapic_tctr0, lapic_tctr1;
 
-/* FIXME: this is only accessed from assembly, never from C. Move to asm? */
-PUBLIC u8_t apicid2cpuid[MAX_NR_APICIDS+1];  /* Accessed from asm */
-
 PRIVATE unsigned apic_imcrp;
-PRIVATE unsigned nintrs;
 PRIVATE const unsigned nlints = 0;
 
+#define apic_eoi() do { *((volatile u32_t *) lapic_eoi_addr) = 0; } while(0)
+
 /*
  * FIXME this should be a cpulocal variable but there are some problems with
  * arch specific cpulocals. As this variable is write-once-read-only it is ok to
@@ -71,8 +156,224 @@ PRIVATE u32_t lapic_bus_freq[CONFIG_MAX_CPUS];
 /* the probe period will be roughly 100ms */
 #define PROBE_TICKS	(system_hz / 10)
 
-PRIVATE u32_t pci_config_intr_data;
-PRIVATE int lapic_extint_assigned = 0;
+#define IOAPIC_IOREGSEL	0x0
+#define IOAPIC_IOWIN	0x10
+
+PUBLIC u32_t ioapic_read(u32_t ioa_base, u32_t reg)
+{
+	*((u32_t *)(ioa_base + IOAPIC_IOREGSEL)) = (reg & 0xff);
+	return *(u32_t *)(ioa_base + IOAPIC_IOWIN);
+}
+
+PRIVATE void ioapic_write(u32_t ioa_base, u8_t reg, u32_t val)
+{
+	*((u32_t *)(ioa_base + IOAPIC_IOREGSEL)) = reg;
+	*((u32_t *)(ioa_base + IOAPIC_IOWIN)) = val;
+}
+
+FORWARD _PROTOTYPE(void lapic_microsec_sleep, (unsigned count));
+FORWARD _PROTOTYPE(void apic_idt_init, (const int reset));
+
+PRIVATE void ioapic_enable_pin(vir_bytes ioapic_addr, int pin)
+{
+	u32_t lo = ioapic_read(ioapic_addr, IOAPIC_REDIR_TABLE + pin * 2);
+
+	lo &= ~APIC_ICR_INT_MASK;
+	ioapic_write(ioapic_addr, IOAPIC_REDIR_TABLE + pin * 2, lo);
+}
+
+PRIVATE void ioapic_disable_pin(vir_bytes ioapic_addr, int pin)
+{
+	u32_t lo = ioapic_read(ioapic_addr, IOAPIC_REDIR_TABLE + pin * 2);
+
+	lo |= APIC_ICR_INT_MASK;
+	ioapic_write(ioapic_addr, IOAPIC_REDIR_TABLE + pin * 2, lo);
+}
+
+PRIVATE void ioapic_redirt_entry_read(void * ioapic_addr,
+					int entry,
+					u32_t *hi,
+					u32_t *lo)
+{
+	*lo = ioapic_read((u32_t)ioapic_addr, (u8_t) (IOAPIC_REDIR_TABLE + entry * 2));
+	*hi = ioapic_read((u32_t)ioapic_addr, (u8_t) (IOAPIC_REDIR_TABLE + entry * 2 + 1));
+
+}
+
+PRIVATE void ioapic_redirt_entry_write(void * ioapic_addr,
+					int entry,
+					u32_t hi,
+					u32_t lo)
+{
+#if 0
+	VERBOSE_APIC(printf("IO apic redir entry %3d "
+				"write 0x%08x 0x%08x\n", entry, hi, lo));
+#endif
+	ioapic_write((u32_t)ioapic_addr, (u8_t) (IOAPIC_REDIR_TABLE + entry * 2 + 1), hi);
+	ioapic_write((u32_t)ioapic_addr, (u8_t) (IOAPIC_REDIR_TABLE + entry * 2), lo);
+}
+
+#define apic_read_tmr_vector(vec) \
+		lapic_read(LAPIC_TMR + 0x10 * ((vec) >> 5))
+
+#define apic_read_irr_vector(vec) \
+		lapic_read(LAPIC_IRR + 0x10 * ((vec) >> 5))
+
+#define apic_read_isr_vector(vec) \
+		lapic_read(LAPIC_ISR + 0x10 * ((vec) >> 5))
+
+#define lapic_test_delivery_val(val, vector) ((val) & (1 << ((vector) & 0x1f)))
+
+PRIVATE void ioapic_eoi_level(struct irq * irq)
+{
+	reg_t tmr;
+
+	tmr = apic_read_tmr_vector(irq->vector);
+	apic_eoi();
+
+	/* 
+	 * test if it was a level or edge triggered interrupt. If delivered as
+	 * edge exec the workaround for broken chipsets
+	 */
+	if (!lapic_test_delivery_val(tmr, irq->vector)) {
+		int is_masked;
+		u32_t lo;
+		
+		panic("EDGE instead of LEVEL!");
+
+		lo = ioapic_read(irq->ioa->addr,
+				IOAPIC_REDIR_TABLE + irq->pin * 2);
+
+		is_masked = lo & APIC_ICR_INT_MASK;
+
+		/* set mask and edge */
+		lo |= APIC_ICR_INT_MASK;
+		lo &= ~APIC_ICR_TRIGGER;
+		ioapic_write(irq->ioa->addr,
+				IOAPIC_REDIR_TABLE + irq->pin * 2, lo);
+
+		/* set back to level and restore the mask bit */
+		lo = ioapic_read(irq->ioa->addr,
+				IOAPIC_REDIR_TABLE + irq->pin * 2);
+
+		lo |= APIC_ICR_TRIGGER;
+		if (is_masked)
+			lo |= APIC_ICR_INT_MASK;
+		else
+			lo &= ~APIC_ICR_INT_MASK;
+		ioapic_write(irq->ioa->addr,
+				IOAPIC_REDIR_TABLE + irq->pin * 2, lo);
+	}
+}
+
+PRIVATE void ioapic_eoi_edge(__unused struct irq * irq)
+{
+	apic_eoi();
+}
+
+PUBLIC void ioapic_eoi(int irq)
+{
+	if (ioapic_enabled) {
+		io_apic_irq[irq].eoi(&io_apic_irq[irq]);
+	}
+	else
+		irq_8259_eoi(irq);
+}
+ 
+PUBLIC int ioapic_enable_all(void)
+{
+	i8259_disable();
+
+	if (apic_imcrp) {
+		/* Select IMCR and disconnect 8259s. */
+		outb(0x22, 0x70);
+		outb(0x23, 0x01);
+	}
+
+	return ioapic_enabled = 1;
+}
+
+/* disables a single IO APIC */
+PRIVATE void ioapic_disable(struct io_apic * ioapic)
+{
+	unsigned p;
+	
+	for (p = 0; p < io_apic->pins; p++) {
+		u32_t low_32, hi_32;
+		low_32 = ioapic_read((u32_t)ioapic->addr,
+				(uint8_t) (IOAPIC_REDIR_TABLE + p * 2));
+		hi_32 = ioapic_read((u32_t)ioapic->addr,
+				(uint8_t) (IOAPIC_REDIR_TABLE + p * 2 + 1));
+
+		if (!(low_32 & APIC_ICR_INT_MASK)) {
+			low_32 |= APIC_ICR_INT_MASK;
+			ioapic_write((u32_t)ioapic->addr,
+				(uint8_t) (IOAPIC_REDIR_TABLE + p * 2 + 1), hi_32);
+			ioapic_write((u32_t)ioapic->addr,
+				(uint8_t) (IOAPIC_REDIR_TABLE + p * 2), low_32);
+		}
+	}
+}
+
+/* disables all IO APICs */
+PUBLIC void ioapic_disable_all(void)
+{
+	unsigned ioa;
+	if (!ioapic_enabled)
+		return;
+
+	for (ioa = 0 ; ioa < nioapics; ioa++) 
+		ioapic_disable(&io_apic[ioa]);
+
+	ioapic_enabled = 0; /* io apic, disabled */
+
+	/* Enable 8259 - write 0x00 in OCW1 master and slave.  */
+	if (apic_imcrp) {
+		outb(0x22, 0x70);
+		outb(0x23, 0x00);
+	}
+
+	lapic_microsec_sleep(200); /* to enable APIC to switch to PIC */
+
+	apic_idt_init(TRUE); /* reset */
+	idt_reload();
+
+	intr_init(INTS_ORIG, 0); /* no auto eoi */
+}
+
+PRIVATE void ioapic_disable_irq(unsigned irq)
+{
+	assert(io_apic_irq[irq].ioa);
+
+	ioapic_disable_pin(io_apic_irq[irq].ioa->addr, io_apic_irq[irq].pin);
+	io_apic_irq[irq].state |= IOAPIC_IRQ_STATE_MASKED;
+}
+
+PRIVATE void ioapic_enable_irq(unsigned irq)
+{
+	assert(io_apic_irq[irq].ioa);
+
+	ioapic_enable_pin(io_apic_irq[irq].ioa->addr, io_apic_irq[irq].pin);
+	io_apic_irq[irq].state &= ~IOAPIC_IRQ_STATE_MASKED;
+}
+
+PUBLIC void ioapic_unmask_irq(unsigned irq)
+{
+	if (ioapic_enabled)
+		ioapic_enable_irq(irq);
+	else
+		/* FIXME unlikely */
+		irq_8259_unmask(irq);
+}
+
+PUBLIC void ioapic_mask_irq(unsigned irq)
+{
+	if (ioapic_enabled)
+		ioapic_disable_irq(irq);
+	else
+		/* FIXME unlikely */
+		irq_8259_mask(irq);
+}
 
 PRIVATE int calib_clk_handler(irq_hook_t * UNUSED(hook))
 {
@@ -91,6 +392,7 @@ PRIVATE int calib_clk_handler(irq_hook_t * UNUSED(hook))
 	else if (probe_ticks == PROBE_TICKS) {
 		lapic_tctr1 = tcrt;
 		tsc1 = tsc;
+		stop_8253A_timer();
 	}
 
 	return 1;
@@ -136,8 +438,8 @@ PRIVATE void apic_calibrate_clocks(void)
 	put_irq_handler(&calib_clk, CLOCK_IRQ, calib_clk_handler);
 
 	/* set the PIC timer to get some time */
-	intr_enable();
 	init_8253A_timer(system_hz);
+	intr_enable();
 
 	/* loop for some time to get a sample */
 	while(probe_ticks < PROBE_TICKS) {
@@ -145,7 +447,6 @@ PRIVATE void apic_calibrate_clocks(void)
 	}
 
 	intr_disable();
-	stop_8253A_timer();
 
 	/* remove the probe */
 	rm_irq_handler(&calib_clk);
@@ -210,7 +511,7 @@ PUBLIC void lapic_stop_timer(void)
 PRIVATE void lapic_microsec_sleep(unsigned count)
 {
 	lapic_set_timer_one_shot(count);
-	while (lapic_read (LAPIC_TIMER_CCR));
+	while (lapic_read(LAPIC_TIMER_CCR));
 }
 
 PRIVATE  u32_t lapic_errstatus(void)
@@ -219,29 +520,49 @@ PRIVATE  u32_t lapic_errstatus(void)
 	return lapic_read(LAPIC_ESR);
 }
 
-PRIVATE void lapic_enable_no_lints(void)
+PRIVATE int lapic_disable_in_msr(void)
 {
-	u32_t val;
+	u64_t msr;
+	u32_t addr;
 
-	val = lapic_read(LAPIC_LINT0);
-	lapic_extint_assigned =	(val & APIC_ICR_DM_MASK) == APIC_ICR_DM_EXTINT;
-	val &= ~(APIC_ICR_DM_MASK|APIC_ICR_INT_MASK);
+	ia32_msr_read(IA32_APIC_BASE, &msr.hi, &msr.lo);
 
-	if (!ioapic_enabled && cpu_is_bsp(cpuid))
-		val |= (APIC_ICR_DM_EXTINT); /* ExtINT at LINT0 */
-	else
-		val |= (APIC_ICR_DM_EXTINT|APIC_ICR_INT_MASK); /* Masked ExtINT at LINT0 */
+	msr.lo &= ~(1 << IA32_APIC_BASE_ENABLE_BIT);
+	ia32_msr_write(IA32_APIC_BASE, msr.hi, msr.lo);
 
-	lapic_write (LAPIC_LINT0, val);
+	return 1;
+}
 
-	val = lapic_read(LAPIC_LINT1);
-	val &= ~(APIC_ICR_DM_MASK|APIC_ICR_INT_MASK);
+PUBLIC void lapic_disable(void)
+{
+	/* Disable current APIC and close interrupts from PIC */
+	u32_t val;
 
-	if (!ioapic_enabled && cpu_is_bsp(cpuid))
-		val |= APIC_ICR_DM_NMI;
-	else
-		val |= (APIC_ICR_DM_NMI | APIC_ICR_INT_MASK); /* NMI at LINT1 */
+	if (!lapic_addr)
+		return;
+	
+	if (!apic_imcrp) {
+		/* leave it enabled if imcr is not set */
+		val = lapic_read(LAPIC_LINT0);
+		val &= ~(APIC_ICR_DM_MASK|APIC_ICR_INT_MASK);
+		val |= APIC_ICR_DM_EXTINT; /* ExtINT at LINT0 */
+		lapic_write (LAPIC_LINT0, val);
+		return;
+	}
+
+	val = lapic_read(LAPIC_LINT0) & 0xFFFE58FF;
+	val |= APIC_ICR_INT_MASK;
+	lapic_write (LAPIC_LINT0, val);
+
+	val = lapic_read(LAPIC_LINT1) & 0xFFFE58FF;
+	val |= APIC_ICR_INT_MASK;
 	lapic_write (LAPIC_LINT1, val);
+
+	val = lapic_read(LAPIC_SIVR) & 0xFFFFFF00;
+	val &= ~APIC_ENABLE;
+	lapic_write(LAPIC_SIVR, val);
+
+	lapic_disable_in_msr();
 }
 
 PRIVATE int lapic_enable_in_msr(void)
@@ -270,9 +591,13 @@ PRIVATE int lapic_enable_in_msr(void)
 	return 1;
 }
 
-PRIVATE int lapic_enable(void)
+PUBLIC int lapic_enable(void)
 {
 	u32_t val, nlvt;
+#if 0
+	u32_t timeout = 0xFFFF;
+	u32_t errstatus = 0;
+#endif
 	unsigned cpu = cpuid;
 
 	if (!lapic_addr)
@@ -288,19 +613,21 @@ PRIVATE int lapic_enable(void)
 	if (!lapic_enable_in_msr())
 		return 0;
 
+	/* set the highest priority for ever */
+	lapic_write(LAPIC_TPR, 0x0);
+
 	lapic_eoi_addr = LAPIC_EOI;
 	/* clear error state register. */
 	val = lapic_errstatus ();
 
 	/* Enable Local APIC and set the spurious vector to 0xff. */
-
-	val = lapic_read(LAPIC_SIVR) & 0xFFFFFF00;
+	val = lapic_read(LAPIC_SIVR);
 	val |= APIC_ENABLE | APIC_SPURIOUS_INT_VECTOR;
 	val &= ~APIC_FOCUS_DISABLED;
 	lapic_write(LAPIC_SIVR, val);
 	(void) lapic_read(LAPIC_SIVR);
 
-	*((u32_t *)lapic_eoi_addr) = 0;
+	apic_eoi();
 
 	cpu = cpuid;
 
@@ -313,10 +640,6 @@ PRIVATE int lapic_enable(void)
 	val = lapic_read(LAPIC_DFR) | 0xF0000000;
 	lapic_write (LAPIC_DFR, val);
 
-	if (nlints == 0) {
-		lapic_enable_no_lints();
-	}
-
 	val = lapic_read (LAPIC_LVTER) & 0xFFFFFF00;
 	lapic_write (LAPIC_LVTER, val);
 
@@ -338,7 +661,7 @@ PRIVATE int lapic_enable(void)
 	lapic_write (LAPIC_TPR, val & ~0xFF);
 
 	(void) lapic_read (LAPIC_SIVR);
-	*((u32_t *)lapic_eoi_addr) = 0;
+	apic_eoi();
 
 	apic_calibrate_clocks();
 	BOOT_VERBOSE(printf("APIC timer calibrated\n"));
@@ -352,24 +675,79 @@ PRIVATE void apic_spurios_intr(void)
 	for(;;);
 }
 
+PRIVATE void apic_error_intr(void)
+{
+	printf("WARNING local apic error interrupt\n");
+	for(;;);
+}
+
 PRIVATE struct gate_table_s gate_table_ioapic[] = {
-	{ apic_hwint00, VECTOR( 0), INTR_PRIVILEGE },
-	{ apic_hwint01, VECTOR( 1), INTR_PRIVILEGE },
-	{ apic_hwint02, VECTOR( 2), INTR_PRIVILEGE },
-	{ apic_hwint03, VECTOR( 3), INTR_PRIVILEGE },
-	{ apic_hwint04, VECTOR( 4), INTR_PRIVILEGE },
-	{ apic_hwint05, VECTOR( 5), INTR_PRIVILEGE },
-	{ apic_hwint06, VECTOR( 6), INTR_PRIVILEGE },
-	{ apic_hwint07, VECTOR( 7), INTR_PRIVILEGE },
-	{ apic_hwint08, VECTOR( 8), INTR_PRIVILEGE },
-	{ apic_hwint09, VECTOR( 9), INTR_PRIVILEGE },
-	{ apic_hwint10, VECTOR(10), INTR_PRIVILEGE },
-	{ apic_hwint11, VECTOR(11), INTR_PRIVILEGE },
-	{ apic_hwint12, VECTOR(12), INTR_PRIVILEGE },
-	{ apic_hwint13, VECTOR(13), INTR_PRIVILEGE },
-	{ apic_hwint14, VECTOR(14), INTR_PRIVILEGE },
-	{ apic_hwint15, VECTOR(15), INTR_PRIVILEGE },
+	{ apic_hwint0, LAPIC_VECTOR( 0), INTR_PRIVILEGE },
+	{ apic_hwint1, LAPIC_VECTOR( 1), INTR_PRIVILEGE },
+	{ apic_hwint2, LAPIC_VECTOR( 2), INTR_PRIVILEGE },
+	{ apic_hwint3, LAPIC_VECTOR( 3), INTR_PRIVILEGE },
+	{ apic_hwint4, LAPIC_VECTOR( 4), INTR_PRIVILEGE },
+	{ apic_hwint5, LAPIC_VECTOR( 5), INTR_PRIVILEGE },
+	{ apic_hwint6, LAPIC_VECTOR( 6), INTR_PRIVILEGE },
+	{ apic_hwint7, LAPIC_VECTOR( 7), INTR_PRIVILEGE },
+	{ apic_hwint8, LAPIC_VECTOR( 8), INTR_PRIVILEGE },
+	{ apic_hwint9, LAPIC_VECTOR( 9), INTR_PRIVILEGE },
+	{ apic_hwint10, LAPIC_VECTOR(10), INTR_PRIVILEGE },
+	{ apic_hwint11, LAPIC_VECTOR(11), INTR_PRIVILEGE },
+	{ apic_hwint12, LAPIC_VECTOR(12), INTR_PRIVILEGE },
+	{ apic_hwint13, LAPIC_VECTOR(13), INTR_PRIVILEGE },
+	{ apic_hwint14, LAPIC_VECTOR(14), INTR_PRIVILEGE },
+	{ apic_hwint15, LAPIC_VECTOR(15), INTR_PRIVILEGE },
+	{ apic_hwint16, LAPIC_VECTOR(16), INTR_PRIVILEGE },
+	{ apic_hwint17, LAPIC_VECTOR(17), INTR_PRIVILEGE },
+	{ apic_hwint18, LAPIC_VECTOR(18), INTR_PRIVILEGE },
+	{ apic_hwint19, LAPIC_VECTOR(19), INTR_PRIVILEGE },
+	{ apic_hwint20, LAPIC_VECTOR(20), INTR_PRIVILEGE },
+	{ apic_hwint21, LAPIC_VECTOR(21), INTR_PRIVILEGE },
+	{ apic_hwint22, LAPIC_VECTOR(22), INTR_PRIVILEGE },
+	{ apic_hwint23, LAPIC_VECTOR(23), INTR_PRIVILEGE },
+	{ apic_hwint24, LAPIC_VECTOR(24), INTR_PRIVILEGE },
+	{ apic_hwint25, LAPIC_VECTOR(25), INTR_PRIVILEGE },
+	{ apic_hwint26, LAPIC_VECTOR(26), INTR_PRIVILEGE },
+	{ apic_hwint27, LAPIC_VECTOR(27), INTR_PRIVILEGE },
+	{ apic_hwint28, LAPIC_VECTOR(28), INTR_PRIVILEGE },
+	{ apic_hwint29, LAPIC_VECTOR(29), INTR_PRIVILEGE },
+	{ apic_hwint30, LAPIC_VECTOR(30), INTR_PRIVILEGE },
+	{ apic_hwint31, LAPIC_VECTOR(31), INTR_PRIVILEGE },
+	{ apic_hwint32, LAPIC_VECTOR(32), INTR_PRIVILEGE },
+	{ apic_hwint33, LAPIC_VECTOR(33), INTR_PRIVILEGE },
+	{ apic_hwint34, LAPIC_VECTOR(34), INTR_PRIVILEGE },
+	{ apic_hwint35, LAPIC_VECTOR(35), INTR_PRIVILEGE },
+	{ apic_hwint36, LAPIC_VECTOR(36), INTR_PRIVILEGE },
+	{ apic_hwint37, LAPIC_VECTOR(37), INTR_PRIVILEGE },
+	{ apic_hwint38, LAPIC_VECTOR(38), INTR_PRIVILEGE },
+	{ apic_hwint39, LAPIC_VECTOR(39), INTR_PRIVILEGE },
+	{ apic_hwint40, LAPIC_VECTOR(40), INTR_PRIVILEGE },
+	{ apic_hwint41, LAPIC_VECTOR(41), INTR_PRIVILEGE },
+	{ apic_hwint42, LAPIC_VECTOR(42), INTR_PRIVILEGE },
+	{ apic_hwint43, LAPIC_VECTOR(43), INTR_PRIVILEGE },
+	{ apic_hwint44, LAPIC_VECTOR(44), INTR_PRIVILEGE },
+	{ apic_hwint45, LAPIC_VECTOR(45), INTR_PRIVILEGE },
+	{ apic_hwint46, LAPIC_VECTOR(46), INTR_PRIVILEGE },
+	{ apic_hwint47, LAPIC_VECTOR(47), INTR_PRIVILEGE },
+	{ apic_hwint48, LAPIC_VECTOR(48), INTR_PRIVILEGE },
+	{ apic_hwint49, LAPIC_VECTOR(49), INTR_PRIVILEGE },
+	{ apic_hwint50, LAPIC_VECTOR(50), INTR_PRIVILEGE },
+	{ apic_hwint51, LAPIC_VECTOR(51), INTR_PRIVILEGE },
+	{ apic_hwint52, LAPIC_VECTOR(52), INTR_PRIVILEGE },
+	{ apic_hwint53, LAPIC_VECTOR(53), INTR_PRIVILEGE },
+	{ apic_hwint54, LAPIC_VECTOR(54), INTR_PRIVILEGE },
+	{ apic_hwint55, LAPIC_VECTOR(55), INTR_PRIVILEGE },
+	{ apic_hwint56, LAPIC_VECTOR(56), INTR_PRIVILEGE },
+	{ apic_hwint57, LAPIC_VECTOR(57), INTR_PRIVILEGE },
+	{ apic_hwint58, LAPIC_VECTOR(58), INTR_PRIVILEGE },
+	{ apic_hwint59, LAPIC_VECTOR(59), INTR_PRIVILEGE },
+	{ apic_hwint60, LAPIC_VECTOR(60), INTR_PRIVILEGE },
+	{ apic_hwint61, LAPIC_VECTOR(61), INTR_PRIVILEGE },
+	{ apic_hwint62, LAPIC_VECTOR(62), INTR_PRIVILEGE },
+	{ apic_hwint63, LAPIC_VECTOR(63), INTR_PRIVILEGE },
 	{ apic_spurios_intr, APIC_SPURIOUS_INT_VECTOR, INTR_PRIVILEGE },
+	{ apic_error_intr, APIC_ERROR_INT_VECTOR, INTR_PRIVILEGE },
 	{ NULL, 0, 0}
 };
 
@@ -379,11 +757,21 @@ PRIVATE struct gate_table_s gate_table_common[] = {
 	{ NULL, 0, 0}
 };
 
+#ifdef CONFIG_SMP
+PRIVATE struct gate_table_s gate_table_smp[] = {
+	{ smp_ipi_sched, SMP_SCHED_PROC, INTR_PRIVILEGE },
+	{ smp_ipi_dequeue, SMP_DEQUEUE_PROC, INTR_PRIVILEGE },
+	{ smp_ipi_reboot,SMP_CPU_REBOOT, INTR_PRIVILEGE },
+	{ smp_ipi_stop,  SMP_CPU_HALT, INTR_PRIVILEGE },
+	{ NULL, 0, 0}
+};
+#endif
+
 #ifdef CONFIG_APIC_DEBUG
 PRIVATE void lapic_set_dummy_handlers(void)
 {
 	char * handler;
-	int vect = 32;
+	int vect = 32; /* skip the reserved vectors */
 
 	handler = &lapic_intr_dummy_handles_start;
 	handler += vect * LAPIC_INTR_DUMMY_HANDLER_SIZE;
@@ -399,6 +787,8 @@ PRIVATE void lapic_set_dummy_handlers(void)
 /* Build descriptors for interrupt gates in IDT. */
 PRIVATE void apic_idt_init(const int reset)
 {
+	u32_t val;
+
 	/* Set up idt tables for smp mode.
 	 */
 	vir_bytes local_timer_intr_handler;
@@ -423,6 +813,17 @@ PRIVATE void apic_idt_init(const int reset)
 
 	idt_copy_vectors(gate_table_common);
 
+#ifdef CONFIG_SMP
+	idt_copy_vectors(gate_table_smp);
+#endif
+
+	/* Setup error interrupt vector */
+	val = lapic_read(LAPIC_LVTER);
+	val |= APIC_ERROR_INT_VECTOR;
+	val &= ~ APIC_ICR_INT_MASK;
+	lapic_write(LAPIC_LVTER, val);
+	(void) lapic_read(LAPIC_LVTER);
+
 	/* configure the timer interupt handler */
 	if (cpu_is_bsp(cpuid)) {
 		local_timer_intr_handler = (vir_bytes) lapic_bsp_timer_int_handler;
@@ -437,6 +838,47 @@ PRIVATE void apic_idt_init(const int reset)
 		PRESENT | INT_GATE_TYPE | (INTR_PRIVILEGE << DPL_SHIFT));
 }
 
+PRIVATE int acpi_get_ioapics(struct io_apic * ioa, unsigned * nioa, unsigned max)
+{
+	unsigned n = 0;
+	struct acpi_madt_ioapic * acpi_ioa;
+
+	while (n < max) {
+		acpi_ioa = acpi_get_ioapic_next();
+		if (acpi_ioa == NULL)
+			break;
+
+		ioa[n].id = acpi_ioa->id;
+		ioa[n].addr = phys2vir(acpi_ioa->address);
+		ioa[n].paddr = (phys_bytes) acpi_ioa->address;
+		ioa[n].gsi_base = acpi_ioa->global_int_base;
+		ioa[n].pins = ((ioapic_read(ioa[n].addr,
+				IOAPIC_VERSION) & 0xff0000) >> 16)+1;
+		printf("IO APIC %d addr 0x%x paddr 0x%x pins %d\n",
+				acpi_ioa->id, ioa[n].addr, ioa[n].paddr,
+				ioa[n].pins);
+
+		n++;
+	}
+
+	*nioa = n;
+	return n;
+}
+
+PRIVATE int detect_ioapics(void)
+{
+	int status;
+
+	if (machine.acpi_rsdp)
+		status = acpi_get_ioapics(io_apic, &nioapics, MAX_NR_IOAPICS);
+	if (!status) {
+		/* try something different like MPS */
+	}
+
+	printf("nioapics %d\n", nioapics);
+	return status;
+}
+
 PUBLIC int apic_single_cpu_init(void)
 {
 	if (!cpu_feature_apic_on_chip())
@@ -450,7 +892,168 @@ PUBLIC int apic_single_cpu_init(void)
 		return 0;
 	}
 
+	acpi_init();
+
+	if (!detect_ioapics()) {
+		lapic_disable();
+		lapic_addr = 0x0;
+		return 0;
+	}
+
+	ioapic_enable_all();
+
+	if (ioapic_enabled)
+		machine.apic_enabled = 1;
+
 	apic_idt_init(0); /* Not a reset ! */
 	idt_reload();
 	return 1;
 }
+
+PRIVATE eoi_method_t set_eoi_method(unsigned irq)
+{
+	/*
+	 * in APIC mode the lowest 16 IRQs are reserved for legacy (E)ISA edge
+	 * triggered interrupts. All the rest is for PCI level triggered
+	 * interrupts
+	 */
+	if (irq < 16)
+		return ioapic_eoi_edge;
+	else
+		return ioapic_eoi_level;
+}
+
+PUBLIC void set_irq_redir_low(unsigned irq, u32_t * low)
+{
+	u32_t val = 0;
+
+	/* clear the polarity, trigger, mask and vector fields */
+	val &= ~(APIC_ICR_VECTOR | APIC_ICR_INT_MASK |
+			APIC_ICR_TRIGGER | APIC_ICR_INT_POLARITY);
+
+	if (irq < 16) {
+		/* ISA active-high */
+		val &= ~APIC_ICR_INT_POLARITY;
+		/* ISA edge triggered */
+		val &= ~APIC_ICR_TRIGGER;
+	}
+	else {
+		/* PCI active-low */
+		val |= APIC_ICR_INT_POLARITY;
+		/* PCI level triggered */
+		val |= APIC_ICR_TRIGGER;
+	}
+
+	val |= io_apic_irq[irq].vector;
+
+	*low = val;
+}
+
+PUBLIC void ioapic_set_irq(unsigned irq)
+{
+	unsigned ioa;
+
+	assert(irq < NR_IRQ_VECTORS);
+	
+	/* shared irq, already set */
+	if (io_apic_irq[irq].ioa && io_apic_irq[irq].eoi)
+		return;
+	
+	assert(!io_apic_irq[irq].ioa || !io_apic_irq[irq].eoi);
+
+	for (ioa = 0; ioa < nioapics; ioa++) {
+		if (io_apic[ioa].gsi_base <= irq &&
+				io_apic[ioa].gsi_base +
+				io_apic[ioa].pins > irq) {
+			u32_t hi_32, low_32;
+
+			io_apic_irq[irq].ioa = &io_apic[ioa];
+			io_apic_irq[irq].pin = irq - io_apic[ioa].gsi_base;
+			io_apic_irq[irq].eoi = set_eoi_method(irq);
+			io_apic_irq[irq].vector = LAPIC_VECTOR(irq);
+
+			set_irq_redir_low(irq, &low_32);
+			/*
+			 * route the interrupts to the bsp by default
+			 */
+			hi_32 = 0;
+			ioapic_redirt_entry_write((void *) io_apic[ioa].addr,
+					io_apic_irq[irq].pin, hi_32, low_32);
+		}
+	}
+}
+
+PUBLIC void ioapic_unset_irq(unsigned irq)
+{
+	assert(irq < NR_IRQ_VECTORS);
+
+	ioapic_disable_irq(irq);
+	io_apic_irq[irq].ioa = NULL;
+	io_apic_irq[irq].eoi = NULL;
+}
+
+PUBLIC void ioapic_reset_pic(void)
+{       
+	apic_idt_init(TRUE); /* reset */
+	idt_reload();
+
+	/* Enable 8259 - write 0x00 in OCW1
+	 * master and slave.  */
+		outb(0x22, 0x70);
+		outb(0x23, 0x00);
+	
+	intr_init(INTS_ORIG, 0); /* no auto eoi */
+}
+
+PRIVATE void irq_lapic_status(int irq)
+{
+	u32_t lo;
+	reg_t tmr, irr, isr;
+	int vector;
+	struct irq * intr;
+
+	intr = &io_apic_irq[irq];
+	
+	if (!intr->ioa)
+		return;
+
+	vector = LAPIC_VECTOR(irq);
+	tmr =  apic_read_tmr_vector(vector);
+	irr =  apic_read_irr_vector(vector);
+	isr =  apic_read_isr_vector(vector);
+
+
+	if (lapic_test_delivery_val(isr, vector)) {
+		printf("IRQ %d vec %d trigger %s irr %d isr %d\n",
+				irq, vector,
+				lapic_test_delivery_val(tmr, vector) ?
+				"level" : "edge",
+				lapic_test_delivery_val(irr, vector) ? 1 : 0,
+				lapic_test_delivery_val(isr, vector) ? 1 : 0);
+	} else {
+		printf("IRQ %d vec %d irr %d\n",
+				irq, vector,
+				lapic_test_delivery_val(irr, vector) ? 1 : 0);
+	}
+	
+	lo = ioapic_read(intr->ioa->addr,
+			IOAPIC_REDIR_TABLE + intr->pin * 2);
+	printf("\tpin %2d vec 0x%02x ioa %d redir_lo 0x%08x %s\n",
+			intr->pin,
+			intr->vector,
+			intr->ioa->id,
+			lo,
+			intr->state & IOAPIC_IRQ_STATE_MASKED ?
+			"masked" : "unmasked");
+}
+
+PUBLIC void dump_apic_irq_state(void)
+{
+	int irq;
+
+	printf("--- IRQs state dump ---\n");
+	for (irq = 0; irq < NR_IRQ_VECTORS; irq++) {
+		irq_lapic_status(irq);
+	}
+	printf("--- all ---\n");
+}
diff --git a/kernel/arch/i386/apic.h b/kernel/arch/i386/apic.h
index 3810ad65c..49adaa8b9 100644
--- a/kernel/arch/i386/apic.h
+++ b/kernel/arch/i386/apic.h
@@ -66,6 +66,9 @@
 #define LAPIC_LDR	(lapic_addr + 0x0d0)
 #define LAPIC_DFR	(lapic_addr + 0x0e0)
 #define LAPIC_SIVR	(lapic_addr + 0x0f0)
+#define LAPIC_ISR	(lapic_addr + 0x100)
+#define LAPIC_TMR	(lapic_addr + 0x180)
+#define LAPIC_IRR	(lapic_addr + 0x200)
 #define LAPIC_ESR	(lapic_addr + 0x280)
 #define LAPIC_ICR1	(lapic_addr + 0x300)
 #define LAPIC_ICR2	(lapic_addr + 0x310)
@@ -84,10 +87,10 @@
 #define IOAPIC_ARB			0x2
 #define IOAPIC_REDIR_TABLE		0x10
 
-#define APIC_TIMER_INT_VECTOR		0xfe
+#define APIC_TIMER_INT_VECTOR		0xf0
+#define APIC_ERROR_INT_VECTOR		0xfe
 #define APIC_SPURIOUS_INT_VECTOR	0xff
 
-
 #ifndef __ASSEMBLY__
 
 #include "kernel/kernel.h"
@@ -95,34 +98,50 @@
 EXTERN vir_bytes lapic_addr;
 EXTERN vir_bytes lapic_eoi_addr;
 
-#define MAX_NR_IOAPICS			32
-#define MAX_NR_BUSES			32
-#define MAX_NR_APICIDS			255
-#define MAX_NR_LCLINTS			2
+#define MAX_NR_IOAPICS		32
+#define MAX_IOAPIC_IRQS		64
+
+EXTERN int ioapic_enabled;
 
-EXTERN u8_t apicid2cpuid[MAX_NR_APICIDS+1];
+struct io_apic {
+	unsigned	id;
+	vir_bytes	addr; /* presently used address */
+	phys_bytes	paddr; /* where is it inphys space */
+	vir_bytes	vaddr; /* adress after paging s on */
+	unsigned	pins;
+	unsigned	gsi_base;
+};
+
+EXTERN struct io_apic io_apic[MAX_NR_IOAPICS];
+EXTERN unsigned nioapics;
 
 EXTERN u32_t lapic_addr_vaddr; /* we remember the virtual address here until we
 				  switch to paging */
 
-/*
-_PROTOTYPE (u32_t ioapic_read, (u32_t addr, u32_t offset));
-_PROTOTYPE (void ioapic_write, (u32_t addr, u32_t offset, u32_t data));
-_PROTOTYPE (void lapic_eoi, (void));
-*/
-
 _PROTOTYPE(int apic_single_cpu_init, (void));
 
 _PROTOTYPE(void lapic_set_timer_periodic, (unsigned freq));
 _PROTOTYPE(void lapic_stop_timer, (void));
 
+_PROTOTYPE(void ioapic_set_irq, (unsigned irq));
+_PROTOTYPE(void ioapic_unset_irq, (unsigned irq));
+
+ /* signal the end of interrupt handler to apic */
+_PROTOTYPE(void ioapic_eoi, (int irq));
+
+_PROTOTYPE(void lapic_disable, (void));
+_PROTOTYPE(void ioapic_disable_all, (void));
+_PROTOTYPE(void ioapic_reset_pic, (void));
+
+_PROTOTYPE(void dump_apic_irq_state, (void));
+
 #include <minix/cpufeature.h>
 
 #define cpu_feature_apic_on_chip() _cpufeature(_CPUF_I386_APIC_ON_CHIP)
 
-#define lapic_read(what)	(*((u32_t *)((what))))
+#define lapic_read(what)	(*((volatile u32_t *)((what))))
 #define lapic_write(what, data)	do {			\
-	(*((u32_t *)((what)))) = data;			\
+	(*((volatile u32_t *)((what)))) = data;			\
 } while(0)
 
 #endif /* __ASSEMBLY__ */
diff --git a/kernel/arch/i386/apic_asm.S b/kernel/arch/i386/apic_asm.S
index ddbd30f59..8a9f7b87c 100644
--- a/kernel/arch/i386/apic_asm.S
+++ b/kernel/arch/i386/apic_asm.S
@@ -5,18 +5,17 @@
 #include <machine/asm.h>
 
 #define APIC_IRQ_HANDLER(irq)	\
-	push	$irq							    	;\
-	call	_C_LABEL(irq_handle)	/* intr_handle(irq_handlers[irq]) */	;\
-	add	$4, %esp						    	;\
-	mov	_C_LABEL(lapic_eoi_addr), %eax				    	;\
-	movl	$0, (%eax)						    	;\
+	push	$irq						;\
+	call	_C_LABEL(irq_handle)		/* intr_handle(irq) */	;\
+	add	$4, %esp					;
 
 /*===========================================================================*/
 /*				interrupt handlers			     */
 /*		interrupt handlers for 386 32-bit protected mode	     */
 /*		APIC interrupt handlers for 386 32-bit protected mode	     */
 /*===========================================================================*/
-#define apic_hwint(irq) \
+#define apic_hwint(irq)							\
+ENTRY(apic_hwint##irq)							\
 	TEST_INT_IN_KERNEL(4, 0f)					;\
 									\
 	SAVE_PROCESS_CTX(0)						;\
@@ -35,73 +34,6 @@
 	popa								;\
 	iret								;
 
-/*  Handlers for hardware interrupts */
-/*  Each of these entry points is an expansion of the hwint_master macro */
-ENTRY(apic_hwint00)
-/*  Interrupt routine for irq 0 (the clock). */
-	apic_hwint(0)
-
-ENTRY(apic_hwint01)
-/*  Interrupt routine for irq 1 (keyboard) */
-	apic_hwint(1)
-
-ENTRY(apic_hwint02)
-/*  Interrupt routine for irq 2 (cascade!) */
-	apic_hwint(2)
-
-ENTRY(apic_hwint03)
-/*  Interrupt routine for irq 3 (second serial) */
-	apic_hwint(3)
-
-ENTRY(apic_hwint04)
-/*  Interrupt routine for irq 4 (first serial) */
-	apic_hwint(4)
-
-ENTRY(apic_hwint05)
-/*  Interrupt routine for irq 5 (XT winchester) */
-	apic_hwint(5)
-
-ENTRY(apic_hwint06)
-/*  Interrupt routine for irq 6 (floppy) */
-	apic_hwint(6)
-
-ENTRY(apic_hwint07)
-/*  Interrupt routine for irq 7 (printer) */
-	apic_hwint(7)
-
-ENTRY(apic_hwint08)
-/*  Interrupt routine for irq 8 (realtime clock) */
-	apic_hwint(8)
-
-ENTRY(apic_hwint09)
-/*  Interrupt routine for irq 9 (irq 2 redirected) */
-	apic_hwint(9)
-
-ENTRY(apic_hwint10)
-/*  Interrupt routine for irq 10 */
-	apic_hwint(10)
-
-ENTRY(apic_hwint11)
-/*  Interrupt routine for irq 11 */
-	apic_hwint(11)
-
-ENTRY(apic_hwint12)
-/*  Interrupt routine for irq 12 */
-	apic_hwint(12)
-
-ENTRY(apic_hwint13)
-/*  Interrupt routine for irq 13 (FPU exception) */
-	apic_hwint(13)
-
-ENTRY(apic_hwint14)
-/*  Interrupt routine for irq 14 (AT winchester) */
-	apic_hwint(14)
-
-ENTRY(apic_hwint15)
-/*  Interrupt routine for irq 15 */
-	apic_hwint(15)
-
-
 #define LAPIC_INTR_HANDLER(func)	\
 	movl	$func, %eax						;\
 	call	*%eax           /* call the actual handler */		;\
@@ -142,7 +74,7 @@ ENTRY(lapic_ap_timer_int_handler)
 
 .data
 lapic_intr_dummy_handler_msg:
-.ascii "UNHABLED APIC interrupt vector %d\n"
+.ascii "UNHANDLED APIC interrupt vector %d\n"
 
 .text
 
@@ -156,6 +88,71 @@ lapic_intr_dummy_handler_msg:
 	.balign	LAPIC_INTR_DUMMY_HANDLER_SIZE;		\
 	lapic_intr_dummy_handler_##vect: lapic_intr_dummy_handler(vect)
 
+apic_hwint(0)
+apic_hwint(1)
+apic_hwint(2)
+apic_hwint(3)
+apic_hwint(4)
+apic_hwint(5)
+apic_hwint(6)
+apic_hwint(7)
+apic_hwint(8)
+apic_hwint(9)
+apic_hwint(10)
+apic_hwint(11)
+apic_hwint(12)
+apic_hwint(13)
+apic_hwint(14)
+apic_hwint(15)
+apic_hwint(16)
+apic_hwint(17)
+apic_hwint(18)
+apic_hwint(19)
+apic_hwint(20)
+apic_hwint(21)
+apic_hwint(22)
+apic_hwint(23)
+apic_hwint(24)
+apic_hwint(25)
+apic_hwint(26)
+apic_hwint(27)
+apic_hwint(28)
+apic_hwint(29)
+apic_hwint(30)
+apic_hwint(31)
+apic_hwint(32)
+apic_hwint(33)
+apic_hwint(34)
+apic_hwint(35)
+apic_hwint(36)
+apic_hwint(37)
+apic_hwint(38)
+apic_hwint(39)
+apic_hwint(40)
+apic_hwint(41)
+apic_hwint(42)
+apic_hwint(43)
+apic_hwint(44)
+apic_hwint(45)
+apic_hwint(46)
+apic_hwint(47)
+apic_hwint(48)
+apic_hwint(49)
+apic_hwint(50)
+apic_hwint(51)
+apic_hwint(52)
+apic_hwint(53)
+apic_hwint(54)
+apic_hwint(55)
+apic_hwint(56)
+apic_hwint(57)
+apic_hwint(58)
+apic_hwint(59)
+apic_hwint(60)
+apic_hwint(61)
+apic_hwint(62)
+apic_hwint(63)
+
 LABEL(lapic_intr_dummy_handles_start)
 	LAPIC_INTR_DUMMY_HANDLER(0)
 	LAPIC_INTR_DUMMY_HANDLER(1)
diff --git a/kernel/arch/i386/apic_asm.h b/kernel/arch/i386/apic_asm.h
index fdb3eb850..8086100d9 100644
--- a/kernel/arch/i386/apic_asm.h
+++ b/kernel/arch/i386/apic_asm.h
@@ -5,22 +5,70 @@
 #ifndef __ASSEMBLY__
 #include "kernel/kernel.h"
 
-_PROTOTYPE( void apic_hwint00, (void) );
-_PROTOTYPE( void apic_hwint01, (void) );
-_PROTOTYPE( void apic_hwint02, (void) );
-_PROTOTYPE( void apic_hwint03, (void) );
-_PROTOTYPE( void apic_hwint04, (void) );
-_PROTOTYPE( void apic_hwint05, (void) );
-_PROTOTYPE( void apic_hwint06, (void) );
-_PROTOTYPE( void apic_hwint07, (void) );
-_PROTOTYPE( void apic_hwint08, (void) );
-_PROTOTYPE( void apic_hwint09, (void) );
+_PROTOTYPE( void apic_hwint0, (void) );
+_PROTOTYPE( void apic_hwint1, (void) );
+_PROTOTYPE( void apic_hwint2, (void) );
+_PROTOTYPE( void apic_hwint3, (void) );
+_PROTOTYPE( void apic_hwint4, (void) );
+_PROTOTYPE( void apic_hwint5, (void) );
+_PROTOTYPE( void apic_hwint6, (void) );
+_PROTOTYPE( void apic_hwint7, (void) );
+_PROTOTYPE( void apic_hwint8, (void) );
+_PROTOTYPE( void apic_hwint9, (void) );
 _PROTOTYPE( void apic_hwint10, (void) );
 _PROTOTYPE( void apic_hwint11, (void) );
 _PROTOTYPE( void apic_hwint12, (void) );
 _PROTOTYPE( void apic_hwint13, (void) );
 _PROTOTYPE( void apic_hwint14, (void) );
 _PROTOTYPE( void apic_hwint15, (void) );
+_PROTOTYPE( void apic_hwint16, (void) );
+_PROTOTYPE( void apic_hwint17, (void) );
+_PROTOTYPE( void apic_hwint18, (void) );
+_PROTOTYPE( void apic_hwint19, (void) );
+_PROTOTYPE( void apic_hwint20, (void) );
+_PROTOTYPE( void apic_hwint21, (void) );
+_PROTOTYPE( void apic_hwint22, (void) );
+_PROTOTYPE( void apic_hwint23, (void) );
+_PROTOTYPE( void apic_hwint24, (void) );
+_PROTOTYPE( void apic_hwint25, (void) );
+_PROTOTYPE( void apic_hwint26, (void) );
+_PROTOTYPE( void apic_hwint27, (void) );
+_PROTOTYPE( void apic_hwint28, (void) );
+_PROTOTYPE( void apic_hwint29, (void) );
+_PROTOTYPE( void apic_hwint30, (void) );
+_PROTOTYPE( void apic_hwint31, (void) );
+_PROTOTYPE( void apic_hwint32, (void) );
+_PROTOTYPE( void apic_hwint33, (void) );
+_PROTOTYPE( void apic_hwint34, (void) );
+_PROTOTYPE( void apic_hwint35, (void) );
+_PROTOTYPE( void apic_hwint36, (void) );
+_PROTOTYPE( void apic_hwint37, (void) );
+_PROTOTYPE( void apic_hwint38, (void) );
+_PROTOTYPE( void apic_hwint39, (void) );
+_PROTOTYPE( void apic_hwint40, (void) );
+_PROTOTYPE( void apic_hwint41, (void) );
+_PROTOTYPE( void apic_hwint42, (void) );
+_PROTOTYPE( void apic_hwint43, (void) );
+_PROTOTYPE( void apic_hwint44, (void) );
+_PROTOTYPE( void apic_hwint45, (void) );
+_PROTOTYPE( void apic_hwint46, (void) );
+_PROTOTYPE( void apic_hwint47, (void) );
+_PROTOTYPE( void apic_hwint48, (void) );
+_PROTOTYPE( void apic_hwint49, (void) );
+_PROTOTYPE( void apic_hwint50, (void) );
+_PROTOTYPE( void apic_hwint51, (void) );
+_PROTOTYPE( void apic_hwint52, (void) );
+_PROTOTYPE( void apic_hwint53, (void) );
+_PROTOTYPE( void apic_hwint54, (void) );
+_PROTOTYPE( void apic_hwint55, (void) );
+_PROTOTYPE( void apic_hwint56, (void) );
+_PROTOTYPE( void apic_hwint57, (void) );
+_PROTOTYPE( void apic_hwint58, (void) );
+_PROTOTYPE( void apic_hwint59, (void) );
+_PROTOTYPE( void apic_hwint60, (void) );
+_PROTOTYPE( void apic_hwint61, (void) );
+_PROTOTYPE( void apic_hwint62, (void) );
+_PROTOTYPE( void apic_hwint63, (void) );
 
 /* The local APIC timer tick handlers */
 _PROTOTYPE(void lapic_bsp_timer_int_handler, (void));
diff --git a/kernel/arch/i386/arch_system.c b/kernel/arch/i386/arch_system.c
index b96674207..438791d2d 100644
--- a/kernel/arch/i386/arch_system.c
+++ b/kernel/arch/i386/arch_system.c
@@ -433,6 +433,11 @@ PRIVATE void ser_debug(const int c)
 		}
 	TOGGLECASE('8', VF_SCHEDULING)
 	TOGGLECASE('9', VF_PICKPROC)
+#endif
+#ifdef CONFIG_APIC
+	case 'I':
+		dump_apic_irq_state();
+		break;
 #endif
 	}
 	serial_debug_active = 0;
diff --git a/kernel/arch/i386/i8259.c b/kernel/arch/i386/i8259.c
index 42674bb5a..c76d68468 100644
--- a/kernel/arch/i386/i8259.c
+++ b/kernel/arch/i386/i8259.c
@@ -84,10 +84,17 @@ PUBLIC void irq_8259_mask(const int irq)
 }
 
 /* Disable 8259 - write 0xFF in OCW1 master and slave. */
-PRIVATE void i8259_disable(void)
+PUBLIC void i8259_disable(void)
 {
 	outb(INT2_CTLMASK, 0xFF);
 	outb(INT_CTLMASK, 0xFF);
 	inb(INT_CTLMASK);
 }
 
+PUBLIC void irq_8259_eoi(int irq)
+{
+	if (irq < 8)
+		eoi_8259_master();
+	else
+		eoi_8259_slave();
+}
diff --git a/kernel/arch/i386/include/hw_intr.h b/kernel/arch/i386/include/hw_intr.h
index 6f70495c9..eaf2c808e 100644
--- a/kernel/arch/i386/include/hw_intr.h
+++ b/kernel/arch/i386/include/hw_intr.h
@@ -2,14 +2,48 @@
 #define __HW_INTR_X86_H__
 
 #include "kernel/kernel.h"
+_PROTOTYPE(int irq_8259_unmask,(int irq));
+_PROTOTYPE(int irq_8259_mask,(int irq));
+_PROTOTYPE(int irq_8259_eoi, (int irq));
+_PROTOTYPE(void irq_handle,(int irq));
+_PROTOTYPE(void i8259_disable,(void));
 
-/* legacy PIC */
+/* 
+ * we don't use IO APIC if not configured for SMP as we cannot read any info
+ * about it unless we use MPS which is not present on all single CPU
+ * configurations. ACPI would be another option, however we don't support it
+ * either
+ */
+#if defined(CONFIG_APIC)
+#include "arch/i386/apic.h"
 
-_PROTOTYPE(void irq_8259_unmask,(int irq));
-_PROTOTYPE(void irq_8259_mask,(int irq));
-_PROTOTYPE(void irq_handle,(int irq));
+#define hw_intr_mask(irq)	ioapic_mask_irq(irq)
+#define hw_intr_unmask(irq)	ioapic_unmask_irq(irq)
+#define hw_intr_ack(irq)	ioapic_eoi(irq)
+#define hw_intr_used(irq)	do {					\
+					if (ioapic_enabled)		\
+						ioapic_set_irq(irq);	\
+				} while (0)
+#define hw_intr_not_used(irq)	do {					\
+					if (ioapic_enabled)		\
+						ioapic_unset_irq(irq);	\
+				} while (0)
+#define hw_intr_disable_all() do {					\
+					ioapic_disable_all();		\
+					ioapic_reset_pic();		\
+					lapic_disable();		\
+				} while (0)
+
+#else
+/* legacy PIC */
 
 #define hw_intr_mask(irq)	irq_8259_mask(irq)
 #define hw_intr_unmask(irq)	irq_8259_unmask(irq)
+#define hw_intr_ack(irq)	irq_8259_eoi(irq)
+#define hw_intr_used(irq)
+#define hw_intr_not_used(irq)
+#define hw_intr_disable_all()
+
+#endif
 
 #endif /* __HW_INTR_X86_H__ */
diff --git a/kernel/arch/i386/klib.S b/kernel/arch/i386/klib.S
index 467fd518a..7f0f93d3c 100644
--- a/kernel/arch/i386/klib.S
+++ b/kernel/arch/i386/klib.S
@@ -888,6 +888,19 @@ ENTRY(poweroff_jmp)
 	
 	/* Jump to 16-bit code that is copied to below 1MB */
 	ljmp	$MON_CS_SELECTOR, $0
+
+/* acknowledge just the master PIC */
+ENTRY(eoi_8259_master)
+	movb	$END_OF_INT, %al
+	outb	$INT_CTL
+	ret
+	
+/* we have to acknowledge both PICs */
+ENTRY(eoi_8259_slave)
+	movb	$END_OF_INT, %al
+	outb	$INT_CTL
+	outb	$INT2_CTL
+	ret
 	
 .data
 idt_ptr:
diff --git a/kernel/arch/i386/memory.c b/kernel/arch/i386/memory.c
index d1d08082c..0feca6814 100644
--- a/kernel/arch/i386/memory.c
+++ b/kernel/arch/i386/memory.c
@@ -1,5 +1,4 @@
 
-
 #include "kernel/kernel.h"
 #include "kernel/proc.h"
 #include "kernel/vm.h"
@@ -955,7 +954,7 @@ void i386_freepde(const int pde)
 	freepdes[nfreepdes++] = pde;
 }
 
-PRIVATE int lapic_mapping_index = -1, oxpcie_mapping_index = -1;
+PRIVATE int oxpcie_mapping_index = -1;
 
 PUBLIC int arch_phys_map(const int index, phys_bytes *addr,
   phys_bytes *len, int *flags)
@@ -967,7 +966,9 @@ PUBLIC int arch_phys_map(const int index, phys_bytes *addr,
 	if(first) {
 #ifdef CONFIG_APIC
 		if(lapic_addr)
-			lapic_mapping_index = freeidx++;
+			freeidx++;
+		if (ioapic_enabled)
+			freeidx += nioapics;
 #endif
 
 #ifdef CONFIG_OXPCIE
@@ -984,12 +985,20 @@ PUBLIC int arch_phys_map(const int index, phys_bytes *addr,
 
 #ifdef CONFIG_APIC
 	/* map the local APIC if enabled */
-	if (index == lapic_mapping_index) {
+	if (index == 0) {
+		if (!lapic_addr)
+			return EINVAL;
 		*addr = vir2phys(lapic_addr);
 		*len = 4 << 10 /* 4kB */;
 		*flags = VMMF_UNCACHED;
 		return OK;
 	}
+	else if (ioapic_enabled && index <= nioapics) {
+		*addr = io_apic[index - 1].paddr;
+		*len = 4 << 10 /* 4kB */;
+		*flags = VMMF_UNCACHED;
+		return OK;
+	}
 #endif
 
 #if CONFIG_OXPCIE
@@ -1008,18 +1017,24 @@ PUBLIC int arch_phys_map_reply(const int index, const vir_bytes addr)
 {
 #ifdef CONFIG_APIC
 	/* if local APIC is enabled */
-	if (index == lapic_mapping_index && lapic_addr) {
+	if (index == 0 && lapic_addr) {
 		lapic_addr_vaddr = addr;
+		return OK;
+	}
+	else if (ioapic_enabled && index <= nioapics) {
+		io_apic[index - 1].vaddr = addr;
+		return OK;
 	}
 #endif
 
 #if CONFIG_OXPCIE
 	if (index == oxpcie_mapping_index) {
 		oxpcie_set_vaddr((unsigned char *) addr);
+		return OK;
 	}
 #endif
 
-	return OK;
+	return EINVAL;
 }
 
 PUBLIC int arch_enable_paging(struct proc * caller, const message * m_ptr)
@@ -1050,11 +1065,21 @@ PUBLIC int arch_enable_paging(struct proc * caller, const message * m_ptr)
 		panic("arch_enable_paging: newmap failed");
 
 #ifdef CONFIG_APIC
+	/* start using the virtual addresses */
+
 	/* if local APIC is enabled */
 	if (lapic_addr) {
 		lapic_addr = lapic_addr_vaddr;
 		lapic_eoi_addr = LAPIC_EOI;
 	}
+	/* if IO apics are enabled */
+	if (ioapic_enabled) {
+		int i;
+
+		for (i = 0; i < nioapics; i++) {
+			io_apic[i].addr = io_apic[i].vaddr;
+		}
+	}
 #endif
 #ifdef CONFIG_WATCHDOG
 	/*
diff --git a/kernel/interrupt.c b/kernel/interrupt.c
index 61a4a6c17..661a4e1c8 100644
--- a/kernel/interrupt.c
+++ b/kernel/interrupt.c
@@ -20,6 +20,7 @@
 #include "archconst.h"
 #include "hw_intr.h"
 
+
 /* number of lists of IRQ hooks, one list per supported line. */
 PRIVATE irq_hook_t* irq_handlers[NR_IRQ_VECTORS] = {0};
 
@@ -58,13 +59,13 @@ PUBLIC void put_irq_handler( irq_hook_t* hook, int irq,
   hook->irq = irq;
   hook->id = id;
   *line = hook;
-  irq_use |= 1 << irq;  /* this does not work for irq >= 32 */
 
   /* And as last enable the irq at the hardware.
    *
    * Internal this activates the line or source of the given interrupt.
    */
   if((irq_actids[hook->irq] &= ~hook->id) == 0) {
+	  hw_intr_used(irq);
 	  hw_intr_unmask(hook->irq);
   }
 }
@@ -86,8 +87,6 @@ PUBLIC void rm_irq_handler( const irq_hook_t* hook ) {
   while( (*line) != NULL ) {
 	if((*line)->id == id) {
 		(*line) = (*line)->next;
-		if(!irq_handlers[irq])
-			irq_use &= ~(1 << irq);
 		if (irq_actids[irq] & id)
 			irq_actids[irq] &= ~id;
     	}
@@ -101,6 +100,7 @@ PUBLIC void rm_irq_handler( const irq_hook_t* hook ) {
    */
   if (irq_handlers[irq] == NULL) {
 	hw_intr_mask(irq);
+	hw_intr_not_used(irq);
   }
   else if (irq_actids[irq] == 0) {
 	hw_intr_unmask(irq);
@@ -155,6 +155,8 @@ PUBLIC void irq_handle(int irq)
   /* reenable the IRQ only if there is no active handler */
   if (irq_actids[irq] == 0)
 	  hw_intr_unmask(irq);
+
+  hw_intr_ack(irq);
 }
 
 /* Enable/Disable a interrupt line.  */
diff --git a/kernel/main.c b/kernel/main.c
index b95ca5bef..df88e040c 100644
--- a/kernel/main.c
+++ b/kernel/main.c
@@ -19,6 +19,7 @@
 #include "proc.h"
 #include "debug.h"
 #include "clock.h"
+#include "hw_intr.h"
 
 /* Prototype declarations for PRIVATE functions. */
 FORWARD _PROTOTYPE( void announce, (void));	
@@ -323,6 +324,7 @@ PUBLIC void minix_shutdown(timer_t *tp)
  * monitor), RBT_MONITOR (execute given code), RBT_RESET (hard reset). 
  */
   arch_stop_local_timer();
+  hw_intr_disable_all();
   intr_init(INTS_ORIG, 0);
   arch_shutdown(tp ? tmr_arg(tp)->ta_int : RBT_PANIC);
 }