MCA: delete all remaining traces of microchannel bus support.

Hardware with MCA bus is limited to 386 and 486 class machines
that are now 20+ years old and typically with less than 32MB
of memory.  A quick search on the internet, and you see that
even the MCA hobbyist/enthusiast community has lost interest
in the early 2000 era and never really even moved ahead from
the 2.4 kernels to the 2.6 series.

This deletes anything remaining related to CONFIG_MCA from core
kernel code and from the x86 architecture.  There is no point in
carrying this any further into the future.

One complication to watch for is inadvertently scooping up
stuff relating to machine check, since there is overlap in
the TLA name space (e.g. arch/x86/boot/mca.c).

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: James Bottomley <JBottomley@Parallels.com>
Cc: x86@kernel.org
Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

9 files changed, 7 insertions, 530 deletions

diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index 532d2e090e6..7d156994720 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -49,7 +49,6 @@ obj-y				+= cpu/
 obj-y				+= acpi/
 obj-y				+= reboot.o
 obj-$(CONFIG_X86_32)		+= reboot_32.o
-obj-$(CONFIG_MCA)		+= mca_32.o
 obj-$(CONFIG_X86_MSR)		+= msr.o
 obj-$(CONFIG_X86_CPUID)		+= cpuid.o
 obj-$(CONFIG_PCI)		+= early-quirks.o
diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
index a415b1f4436..f564b189de1 100644
--- a/arch/x86/kernel/acpi/boot.c
+++ b/arch/x86/kernel/acpi/boot.c
@@ -990,7 +990,7 @@ void __init mp_config_acpi_legacy_irqs(void)
 	int i;
 	struct mpc_intsrc mp_irq;
 
-#if defined (CONFIG_MCA) || defined (CONFIG_EISA)
+#ifdef CONFIG_EISA
 	/*
 	 * Fabricate the legacy ISA bus (bus #31).
 	 */
diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index e88300d8e80..675e9045a3c 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -142,7 +142,7 @@ int mp_irq_entries;
 /* GSI interrupts */
 static int nr_irqs_gsi = NR_IRQS_LEGACY;
 
-#if defined (CONFIG_MCA) || defined (CONFIG_EISA)
+#ifdef CONFIG_EISA
 int mp_bus_id_to_type[MAX_MP_BUSSES];
 #endif
 
@@ -875,7 +875,7 @@ static int __init find_isa_irq_apic(int irq, int type)
 	return -1;
 }
 
-#if defined(CONFIG_EISA) || defined(CONFIG_MCA)
+#ifdef CONFIG_EISA
 /*
  * EISA Edge/Level control register, ELCR
  */
@@ -912,12 +912,6 @@ static int EISA_ELCR(unsigned int irq)
 #define default_PCI_trigger(idx)	(1)
 #define default_PCI_polarity(idx)	(1)
 
-/* MCA interrupts are always polarity zero level triggered,
- * when listed as conforming in the MP table. */
-
-#define default_MCA_trigger(idx)	(1)
-#define default_MCA_polarity(idx)	default_ISA_polarity(idx)
-
 static int irq_polarity(int idx)
 {
 	int bus = mp_irqs[idx].srcbus;
@@ -975,7 +969,7 @@ static int irq_trigger(int idx)
 				trigger = default_ISA_trigger(idx);
 			else
 				trigger = default_PCI_trigger(idx);
-#if defined(CONFIG_EISA) || defined(CONFIG_MCA)
+#ifdef CONFIG_EISA
 			switch (mp_bus_id_to_type[bus]) {
 				case MP_BUS_ISA: /* ISA pin */
 				{
@@ -992,11 +986,6 @@ static int irq_trigger(int idx)
 					/* set before the switch */
 					break;
 				}
-				case MP_BUS_MCA: /* MCA pin */
-				{
-					trigger = default_MCA_trigger(idx);
-					break;
-				}
 				default:
 				{
 					printk(KERN_WARNING "broken BIOS!!\n");
diff --git a/arch/x86/kernel/mca_32.c b/arch/x86/kernel/mca_32.c
deleted file mode 100644
index 7eb1e2b9782..00000000000
--- a/arch/x86/kernel/mca_32.c
+++ /dev/null
@@ -1,476 +0,0 @@
-/*
- *  Written by Martin Kolinek, February 1996
- *
- * Changes:
- *
- *	Chris Beauregard July 28th, 1996
- *	- Fixed up integrated SCSI detection
- *
- *	Chris Beauregard August 3rd, 1996
- *	- Made mca_info local
- *	- Made integrated registers accessible through standard function calls
- *	- Added name field
- *	- More sanity checking
- *
- *	Chris Beauregard August 9th, 1996
- *	- Rewrote /proc/mca
- *
- *	Chris Beauregard January 7th, 1997
- *	- Added basic NMI-processing
- *	- Added more information to mca_info structure
- *
- *	David Weinehall October 12th, 1998
- *	- Made a lot of cleaning up in the source
- *	- Added use of save_flags / restore_flags
- *	- Added the 'driver_loaded' flag in MCA_adapter
- *	- Added an alternative implemention of ZP Gu's mca_find_unused_adapter
- *
- *	David Weinehall March 24th, 1999
- *	- Fixed the output of 'Driver Installed' in /proc/mca/pos
- *	- Made the Integrated Video & SCSI show up even if they have id 0000
- *
- *	Alexander Viro November 9th, 1999
- *	- Switched to regular procfs methods
- *
- *	Alfred Arnold & David Weinehall August 23rd, 2000
- *	- Added support for Planar POS-registers
- */
-
-#include <linux/module.h>
-#include <linux/types.h>
-#include <linux/errno.h>
-#include <linux/kernel.h>
-#include <linux/mca.h>
-#include <linux/kprobes.h>
-#include <linux/slab.h>
-#include <asm/io.h>
-#include <linux/proc_fs.h>
-#include <linux/mman.h>
-#include <linux/mm.h>
-#include <linux/pagemap.h>
-#include <linux/ioport.h>
-#include <asm/uaccess.h>
-#include <linux/init.h>
-
-static unsigned char which_scsi;
-
-int MCA_bus;
-EXPORT_SYMBOL(MCA_bus);
-
-/*
- * Motherboard register spinlock. Untested on SMP at the moment, but
- * are there any MCA SMP boxes?
- *
- * Yes - Alan
- */
-static DEFINE_SPINLOCK(mca_lock);
-
-/* Build the status info for the adapter */
-
-static void mca_configure_adapter_status(struct mca_device *mca_dev)
-{
-	mca_dev->status = MCA_ADAPTER_NONE;
-
-	mca_dev->pos_id = mca_dev->pos[0]
-		+ (mca_dev->pos[1] << 8);
-
-	if (!mca_dev->pos_id && mca_dev->slot < MCA_MAX_SLOT_NR) {
-
-		/*
-		 * id = 0x0000 usually indicates hardware failure,
-		 * however, ZP Gu (zpg@castle.net> reports that his 9556
-		 * has 0x0000 as id and everything still works. There
-		 * also seem to be an adapter with id = 0x0000; the
-		 * NCR Parallel Bus Memory Card. Until this is confirmed,
-		 * however, this code will stay.
-		 */
-
-		mca_dev->status = MCA_ADAPTER_ERROR;
-
-		return;
-	} else if (mca_dev->pos_id != 0xffff) {
-
-		/*
-		 * 0xffff usually indicates that there's no adapter,
-		 * however, some integrated adapters may have 0xffff as
-		 * their id and still be valid. Examples are on-board
-		 * VGA of the 55sx, the integrated SCSI of the 56 & 57,
-		 * and possibly also the 95 ULTIMEDIA.
-		 */
-
-		mca_dev->status = MCA_ADAPTER_NORMAL;
-	}
-
-	if ((mca_dev->pos_id == 0xffff ||
-	    mca_dev->pos_id == 0x0000) && mca_dev->slot >= MCA_MAX_SLOT_NR) {
-		int j;
-
-		for (j = 2; j < 8; j++) {
-			if (mca_dev->pos[j] != 0xff) {
-				mca_dev->status = MCA_ADAPTER_NORMAL;
-				break;
-			}
-		}
-	}
-
-	if (!(mca_dev->pos[2] & MCA_ENABLED)) {
-
-		/* enabled bit is in POS 2 */
-
-		mca_dev->status = MCA_ADAPTER_DISABLED;
-	}
-} /* mca_configure_adapter_status */
-
-/*--------------------------------------------------------------------*/
-
-static struct resource mca_standard_resources[] = {
-	{ .start = 0x60, .end = 0x60, .name = "system control port B (MCA)" },
-	{ .start = 0x90, .end = 0x90, .name = "arbitration (MCA)" },
-	{ .start = 0x91, .end = 0x91, .name = "card Select Feedback (MCA)" },
-	{ .start = 0x92, .end = 0x92, .name = "system Control port A (MCA)" },
-	{ .start = 0x94, .end = 0x94, .name = "system board setup (MCA)" },
-	{ .start = 0x96, .end = 0x97, .name = "POS (MCA)" },
-	{ .start = 0x100, .end = 0x107, .name = "POS (MCA)" }
-};
-
-#define MCA_STANDARD_RESOURCES	ARRAY_SIZE(mca_standard_resources)
-
-/*
- *	mca_read_and_store_pos - read the POS registers into a memory buffer
- *      @pos: a char pointer to 8 bytes, contains the POS register value on
- *            successful return
- *
- *	Returns 1 if a card actually exists (i.e. the pos isn't
- *	all 0xff) or 0 otherwise
- */
-static int mca_read_and_store_pos(unsigned char *pos)
-{
-	int j;
-	int found = 0;
-
-	for (j = 0; j < 8; j++) {
-		pos[j] = inb_p(MCA_POS_REG(j));
-		if (pos[j] != 0xff) {
-			/* 0xff all across means no device. 0x00 means
-			 * something's broken, but a device is
-			 * probably there.  However, if you get 0x00
-			 * from a motherboard register it won't matter
-			 * what we find.  For the record, on the
-			 * 57SLC, the integrated SCSI adapter has
-			 * 0xffff for the adapter ID, but nonzero for
-			 * other registers.  */
-
-			found = 1;
-		}
-	}
-	return found;
-}
-
-static unsigned char mca_pc_read_pos(struct mca_device *mca_dev, int reg)
-{
-	unsigned char byte;
-	unsigned long flags;
-
-	if (reg < 0 || reg >= 8)
-		return 0;
-
-	spin_lock_irqsave(&mca_lock, flags);
-	if (mca_dev->pos_register) {
-		/* Disable adapter setup, enable motherboard setup */
-
-		outb_p(0, MCA_ADAPTER_SETUP_REG);
-		outb_p(mca_dev->pos_register, MCA_MOTHERBOARD_SETUP_REG);
-
-		byte = inb_p(MCA_POS_REG(reg));
-		outb_p(0xff, MCA_MOTHERBOARD_SETUP_REG);
-	} else {
-
-		/* Make sure motherboard setup is off */
-
-		outb_p(0xff, MCA_MOTHERBOARD_SETUP_REG);
-
-		/* Read the appropriate register */
-
-		outb_p(0x8|(mca_dev->slot & 0xf), MCA_ADAPTER_SETUP_REG);
-		byte = inb_p(MCA_POS_REG(reg));
-		outb_p(0, MCA_ADAPTER_SETUP_REG);
-	}
-	spin_unlock_irqrestore(&mca_lock, flags);
-
-	mca_dev->pos[reg] = byte;
-
-	return byte;
-}
-
-static void mca_pc_write_pos(struct mca_device *mca_dev, int reg,
-			     unsigned char byte)
-{
-	unsigned long flags;
-
-	if (reg < 0 || reg >= 8)
-		return;
-
-	spin_lock_irqsave(&mca_lock, flags);
-
-	/* Make sure motherboard setup is off */
-
-	outb_p(0xff, MCA_MOTHERBOARD_SETUP_REG);
-
-	/* Read in the appropriate register */
-
-	outb_p(0x8|(mca_dev->slot&0xf), MCA_ADAPTER_SETUP_REG);
-	outb_p(byte, MCA_POS_REG(reg));
-	outb_p(0, MCA_ADAPTER_SETUP_REG);
-
-	spin_unlock_irqrestore(&mca_lock, flags);
-
-	/* Update the global register list, while we have the byte */
-
-	mca_dev->pos[reg] = byte;
-
-}
-
-/* for the primary MCA bus, we have identity transforms */
-static int mca_dummy_transform_irq(struct mca_device *mca_dev, int irq)
-{
-	return irq;
-}
-
-static int mca_dummy_transform_ioport(struct mca_device *mca_dev, int port)
-{
-	return port;
-}
-
-static void *mca_dummy_transform_memory(struct mca_device *mca_dev, void *mem)
-{
-	return mem;
-}
-
-
-static int __init mca_init(void)
-{
-	unsigned int i, j;
-	struct mca_device *mca_dev;
-	unsigned char pos[8];
-	short mca_builtin_scsi_ports[] = {0xf7, 0xfd, 0x00};
-	struct mca_bus *bus;
-
-	/*
-	 * WARNING: Be careful when making changes here. Putting an adapter
-	 * and the motherboard simultaneously into setup mode may result in
-	 * damage to chips (according to The Indispensable PC Hardware Book
-	 * by Hans-Peter Messmer). Also, we disable system interrupts (so
-	 * that we are not disturbed in the middle of this).
-	 */
-
-	/* Make sure the MCA bus is present */
-
-	if (mca_system_init()) {
-		printk(KERN_ERR "MCA bus system initialisation failed\n");
-		return -ENODEV;
-	}
-
-	if (!MCA_bus)
-		return -ENODEV;
-
-	printk(KERN_INFO "Micro Channel bus detected.\n");
-
-	/* All MCA systems have at least a primary bus */
-	bus = mca_attach_bus(MCA_PRIMARY_BUS);
-	if (!bus)
-		goto out_nomem;
-	bus->default_dma_mask = 0xffffffffLL;
-	bus->f.mca_write_pos = mca_pc_write_pos;
-	bus->f.mca_read_pos = mca_pc_read_pos;
-	bus->f.mca_transform_irq = mca_dummy_transform_irq;
-	bus->f.mca_transform_ioport = mca_dummy_transform_ioport;
-	bus->f.mca_transform_memory = mca_dummy_transform_memory;
-
-	/* get the motherboard device */
-	mca_dev = kzalloc(sizeof(struct mca_device), GFP_KERNEL);
-	if (unlikely(!mca_dev))
-		goto out_nomem;
-
-	/*
-	 * We do not expect many MCA interrupts during initialization,
-	 * but let us be safe:
-	 */
-	spin_lock_irq(&mca_lock);
-
-	/* Make sure adapter setup is off */
-
-	outb_p(0, MCA_ADAPTER_SETUP_REG);
-
-	/* Read motherboard POS registers */
-
-	mca_dev->pos_register = 0x7f;
-	outb_p(mca_dev->pos_register, MCA_MOTHERBOARD_SETUP_REG);
-	mca_dev->name[0] = 0;
-	mca_read_and_store_pos(mca_dev->pos);
-	mca_configure_adapter_status(mca_dev);
-	/* fake POS and slot for a motherboard */
-	mca_dev->pos_id = MCA_MOTHERBOARD_POS;
-	mca_dev->slot = MCA_MOTHERBOARD;
-	mca_register_device(MCA_PRIMARY_BUS, mca_dev);
-
-	mca_dev = kzalloc(sizeof(struct mca_device), GFP_ATOMIC);
-	if (unlikely(!mca_dev))
-		goto out_unlock_nomem;
-
-	/* Put motherboard into video setup mode, read integrated video
-	 * POS registers, and turn motherboard setup off.
-	 */
-
-	mca_dev->pos_register = 0xdf;
-	outb_p(mca_dev->pos_register, MCA_MOTHERBOARD_SETUP_REG);
-	mca_dev->name[0] = 0;
-	mca_read_and_store_pos(mca_dev->pos);
-	mca_configure_adapter_status(mca_dev);
-	/* fake POS and slot for the integrated video */
-	mca_dev->pos_id = MCA_INTEGVIDEO_POS;
-	mca_dev->slot = MCA_INTEGVIDEO;
-	mca_register_device(MCA_PRIMARY_BUS, mca_dev);
-
-	/*
-	 * Put motherboard into scsi setup mode, read integrated scsi
-	 * POS registers, and turn motherboard setup off.
-	 *
-	 * It seems there are two possible SCSI registers. Martin says that
-	 * for the 56,57, 0xf7 is the one, but fails on the 76.
-	 * Alfredo (apena@vnet.ibm.com) says
-	 * 0xfd works on his machine. We'll try both of them. I figure it's
-	 * a good bet that only one could be valid at a time. This could
-	 * screw up though if one is used for something else on the other
-	 * machine.
-	 */
-
-	for (i = 0; (which_scsi = mca_builtin_scsi_ports[i]) != 0; i++) {
-		outb_p(which_scsi, MCA_MOTHERBOARD_SETUP_REG);
-		if (mca_read_and_store_pos(pos))
-			break;
-	}
-	if (which_scsi) {
-		/* found a scsi card */
-		mca_dev = kzalloc(sizeof(struct mca_device), GFP_ATOMIC);
-		if (unlikely(!mca_dev))
-			goto out_unlock_nomem;
-
-		for (j = 0; j < 8; j++)
-			mca_dev->pos[j] = pos[j];
-
-		mca_configure_adapter_status(mca_dev);
-		/* fake POS and slot for integrated SCSI controller */
-		mca_dev->pos_id = MCA_INTEGSCSI_POS;
-		mca_dev->slot = MCA_INTEGSCSI;
-		mca_dev->pos_register = which_scsi;
-		mca_register_device(MCA_PRIMARY_BUS, mca_dev);
-	}
-
-	/* Turn off motherboard setup */
-
-	outb_p(0xff, MCA_MOTHERBOARD_SETUP_REG);
-
-	/*
-	 * Now loop over MCA slots: put each adapter into setup mode, and
-	 * read its POS registers. Then put adapter setup off.
-	 */
-
-	for (i = 0; i < MCA_MAX_SLOT_NR; i++) {
-		outb_p(0x8|(i&0xf), MCA_ADAPTER_SETUP_REG);
-		if (!mca_read_and_store_pos(pos))
-			continue;
-
-		mca_dev = kzalloc(sizeof(struct mca_device), GFP_ATOMIC);
-		if (unlikely(!mca_dev))
-			goto out_unlock_nomem;
-
-		for (j = 0; j < 8; j++)
-			mca_dev->pos[j] = pos[j];
-
-		mca_dev->driver_loaded = 0;
-		mca_dev->slot = i;
-		mca_dev->pos_register = 0;
-		mca_configure_adapter_status(mca_dev);
-		mca_register_device(MCA_PRIMARY_BUS, mca_dev);
-	}
-	outb_p(0, MCA_ADAPTER_SETUP_REG);
-
-	/* Enable interrupts and return memory start */
-	spin_unlock_irq(&mca_lock);
-
-	for (i = 0; i < MCA_STANDARD_RESOURCES; i++)
-		request_resource(&ioport_resource, mca_standard_resources + i);
-
-	mca_do_proc_init();
-
-	return 0;
-
- out_unlock_nomem:
-	spin_unlock_irq(&mca_lock);
- out_nomem:
-	printk(KERN_EMERG "Failed memory allocation in MCA setup!\n");
-	return -ENOMEM;
-}
-
-subsys_initcall(mca_init);
-
-/*--------------------------------------------------------------------*/
-
-static __kprobes void
-mca_handle_nmi_device(struct mca_device *mca_dev, int check_flag)
-{
-	int slot = mca_dev->slot;
-
-	if (slot == MCA_INTEGSCSI) {
-		printk(KERN_CRIT "NMI: caused by MCA integrated SCSI adapter (%s)\n",
-			mca_dev->name);
-	} else if (slot == MCA_INTEGVIDEO) {
-		printk(KERN_CRIT "NMI: caused by MCA integrated video adapter (%s)\n",
-			mca_dev->name);
-	} else if (slot == MCA_MOTHERBOARD) {
-		printk(KERN_CRIT "NMI: caused by motherboard (%s)\n",
-			mca_dev->name);
-	}
-
-	/* More info available in POS 6 and 7? */
-
-	if (check_flag) {
-		unsigned char pos6, pos7;
-
-		pos6 = mca_device_read_pos(mca_dev, 6);
-		pos7 = mca_device_read_pos(mca_dev, 7);
-
-		printk(KERN_CRIT "NMI: POS 6 = 0x%x, POS 7 = 0x%x\n", pos6, pos7);
-	}
-
-} /* mca_handle_nmi_slot */
-
-/*--------------------------------------------------------------------*/
-
-static int __kprobes mca_handle_nmi_callback(struct device *dev, void *data)
-{
-	struct mca_device *mca_dev = to_mca_device(dev);
-	unsigned char pos5;
-
-	pos5 = mca_device_read_pos(mca_dev, 5);
-
-	if (!(pos5 & 0x80)) {
-		/*
-		 *  Bit 7 of POS 5 is reset when this adapter has a hardware
-		 * error. Bit 7 it reset if there's error information
-		 * available in POS 6 and 7.
-		 */
-		mca_handle_nmi_device(mca_dev, !(pos5 & 0x40));
-		return 1;
-	}
-	return 0;
-}
-
-void __kprobes mca_handle_nmi(void)
-{
-	/*
-	 *  First try - scan the various adapters and see if a specific
-	 * adapter was responsible for the error.
-	 */
-	bus_for_each_dev(&mca_bus_type, NULL, NULL, mca_handle_nmi_callback);
-}
diff --git a/arch/x86/kernel/mpparse.c b/arch/x86/kernel/mpparse.c
index ca470e4c92d..b02d4dd6b8a 100644
--- a/arch/x86/kernel/mpparse.c
+++ b/arch/x86/kernel/mpparse.c
@@ -97,7 +97,7 @@ static void __init MP_bus_info(struct mpc_bus *m)
 
 	set_bit(m->busid, mp_bus_not_pci);
 	if (strncmp(str, BUSTYPE_ISA, sizeof(BUSTYPE_ISA) - 1) == 0) {
-#if defined(CONFIG_EISA) || defined(CONFIG_MCA)
+#ifdef CONFIG_EISA
 		mp_bus_id_to_type[m->busid] = MP_BUS_ISA;
 #endif
 	} else if (strncmp(str, BUSTYPE_PCI, sizeof(BUSTYPE_PCI) - 1) == 0) {
@@ -105,12 +105,10 @@ static void __init MP_bus_info(struct mpc_bus *m)
 			x86_init.mpparse.mpc_oem_pci_bus(m);
 
 		clear_bit(m->busid, mp_bus_not_pci);
-#if defined(CONFIG_EISA) || defined(CONFIG_MCA)
+#ifdef CONFIG_EISA
 		mp_bus_id_to_type[m->busid] = MP_BUS_PCI;
 	} else if (strncmp(str, BUSTYPE_EISA, sizeof(BUSTYPE_EISA) - 1) == 0) {
 		mp_bus_id_to_type[m->busid] = MP_BUS_EISA;
-	} else if (strncmp(str, BUSTYPE_MCA, sizeof(BUSTYPE_MCA) - 1) == 0) {
-		mp_bus_id_to_type[m->busid] = MP_BUS_MCA;
 #endif
 	} else
 		printk(KERN_WARNING "Unknown bustype %s - ignoring\n", str);
@@ -368,9 +366,6 @@ static void __init construct_ioapic_table(int mpc_default_type)
 	case 3:
 		memcpy(bus.bustype, "EISA  ", 6);
 		break;
-	case 4:
-	case 7:
-		memcpy(bus.bustype, "MCA   ", 6);
 	}
 	MP_bus_info(&bus);
 	if (mpc_default_type > 4) {
@@ -623,7 +618,7 @@ void __init default_find_smp_config(void)
 		return;
 	/*
 	 * If it is an SMP machine we should know now, unless the
-	 * configuration is in an EISA/MCA bus machine with an
+	 * configuration is in an EISA bus machine with an
 	 * extended bios data area.
 	 *
 	 * there is a real-mode segmented pointer pointing to the
diff --git a/arch/x86/kernel/nmi.c b/arch/x86/kernel/nmi.c
index 47acaf31916..7b3fdfdabf9 100644
--- a/arch/x86/kernel/nmi.c
+++ b/arch/x86/kernel/nmi.c
@@ -19,8 +19,6 @@
 #include <linux/slab.h>
 #include <linux/export.h>
 
-#include <linux/mca.h>
-
 #if defined(CONFIG_EDAC)
 #include <linux/edac.h>
 #endif
@@ -282,16 +280,6 @@ unknown_nmi_error(unsigned char reason, struct pt_regs *regs)
 
 	__this_cpu_add(nmi_stats.unknown, 1);
 
-#ifdef CONFIG_MCA
-	/*
-	 * Might actually be able to figure out what the guilty party
-	 * is:
-	 */
-	if (MCA_bus) {
-		mca_handle_nmi();
-		return;
-	}
-#endif
 	pr_emerg("Uhhuh. NMI received for unknown reason %02x on CPU %d.\n",
 		 reason, smp_processor_id());
 
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 1a290156205..879166402bf 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -34,7 +34,6 @@
 #include <linux/memblock.h>
 #include <linux/seq_file.h>
 #include <linux/console.h>
-#include <linux/mca.h>
 #include <linux/root_dev.h>
 #include <linux/highmem.h>
 #include <linux/module.h>
@@ -179,12 +178,6 @@ struct cpuinfo_x86 new_cpu_data __cpuinitdata = {0, 0, 0, 0, -1, 1, 0, 0, -1};
 /* common cpu data for all cpus */
 struct cpuinfo_x86 boot_cpu_data __read_mostly = {0, 0, 0, 0, -1, 1, 0, 0, -1};
 EXPORT_SYMBOL(boot_cpu_data);
-static void set_mca_bus(int x)
-{
-#ifdef CONFIG_MCA
-	MCA_bus = x;
-#endif
-}
 
 unsigned int def_to_bigsmp;
 
@@ -717,7 +710,6 @@ void __init setup_arch(char **cmdline_p)
 	apm_info.bios = boot_params.apm_bios_info;
 	ist_info = boot_params.ist_info;
 	if (boot_params.sys_desc_table.length != 0) {
-		set_mca_bus(boot_params.sys_desc_table.table[3] & 0x2);
 		machine_id = boot_params.sys_desc_table.table[0];
 		machine_submodel_id = boot_params.sys_desc_table.table[1];
 		BIOS_revision = boot_params.sys_desc_table.table[2];
diff --git a/arch/x86/kernel/time.c b/arch/x86/kernel/time.c
index c6eba2b4267..24d3c91e981 100644
--- a/arch/x86/kernel/time.c
+++ b/arch/x86/kernel/time.c
@@ -14,7 +14,6 @@
 #include <linux/i8253.h>
 #include <linux/time.h>
 #include <linux/export.h>
-#include <linux/mca.h>
 
 #include <asm/vsyscall.h>
 #include <asm/x86_init.h>
@@ -58,11 +57,6 @@ EXPORT_SYMBOL(profile_pc);
 static irqreturn_t timer_interrupt(int irq, void *dev_id)
 {
 	global_clock_event->event_handler(global_clock_event);
-
-	/* MCA bus quirk: Acknowledge irq0 by setting bit 7 in port 0x61 */
-	if (MCA_bus)
-		outb_p(inb_p(0x61)| 0x80, 0x61);
-
 	return IRQ_HANDLED;
 }
 
diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index ff9281f1602..4754f510b36 100644
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -37,10 +37,6 @@
 #include <linux/eisa.h>
 #endif
 
-#ifdef CONFIG_MCA
-#include <linux/mca.h>
-#endif
-
 #if defined(CONFIG_EDAC)
 #include <linux/edac.h>
 #endif