diff --git a/sys/amd64/amd64/initcpu.c b/sys/amd64/amd64/initcpu.c
new file mode 100644
index 000000000000..482f0a2c02d7
--- /dev/null
+++ b/sys/amd64/amd64/initcpu.c
@@ -0,0 +1,444 @@
+/*
+ * Copyright (c) KATO Takenori, 1997.
+ * 
+ * All rights reserved.  Unpublished rights reserved under the copyright
+ * laws of Japan.
+ * 
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer as
+ *    the first lines of this file unmodified.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ *		$Id$
+ */
+
+#include "opt_cpu.h"
+
+#include <sys/param.h>
+#include <sys/kernel.h>
+#include <sys/systm.h>
+
+#include <machine/cpu.h>
+#include <machine/cputypes.h>
+#include <machine/md_var.h>
+#include <machine/specialreg.h>
+
+void initializecpu(void);
+#ifdef I486_CPU
+static void init_5x86(void);
+static void init_bluelightning(void);
+static void init_486dlc(void);
+#ifdef CPU_I486_ON_386
+static void init_i486_on_386(void);
+#endif
+static void init_6x86(void);
+#endif /* I486_CPU */
+
+#ifdef I486_CPU
+/*
+ * IBM Blue Lightning
+ */
+static void
+init_bluelightning(void)
+{
+	u_long	eflags;
+
+#if defined(PC98) && !defined(CPU_UPGRADE_HW_CACHE)
+	need_post_dma_flush = 1;
+#endif
+
+	eflags = read_eflags();
+	disable_intr();
+
+	load_cr0(rcr0() | CR0_CD | CR0_NW);
+	invd();
+
+#ifdef CPU_BLUELIGHTNING_FPU_OP_CACHE
+	wrmsr(0x1000, 0x9c92LL);	/* FP operand can be cacheable on Cyrix FPU */
+#else
+	wrmsr(0x1000, 0x1c92LL);	/* Intel FPU */
+#endif
+	/* Enables 13MB and 0-640KB cache. */
+	wrmsr(0x1001, (0xd0LL << 32) | 0x3ff);
+#ifdef CPU_BLUELIGHTNING_3X
+	wrmsr(0x1002, 0x04000000LL);	/* Enables triple-clock mode. */
+#else
+	wrmsr(0x1002, 0x03000000LL);	/* Enables double-clock mode. */
+#endif
+
+	/* Enable caching in CR0. */
+	load_cr0(rcr0() & ~(CR0_CD | CR0_NW));	/* CD = 0 and NW = 0 */
+	invd();
+	write_eflags(eflags);
+}
+
+/*
+ * Cyrix 486 series
+ */
+static void
+init_486dlc(void)
+{
+	u_long	eflags;
+	u_char	ccr0;
+
+	eflags = read_eflags();
+	disable_intr();
+
+	load_cr0(rcr0() | CR0_CD | CR0_NW);
+	invd();
+
+	ccr0 = read_cyrix_reg(CCR0);
+#ifndef CYRIX_CACHE_WORKS
+	ccr0 |= CCR0_NC1 | CCR0_BARB;
+	write_cyrix_reg(CCR0, ccr0);
+	invd();
+#else
+	ccr0 &= ~CCR0_NC0;
+#ifndef CYRIX_CACHE_REALLY_WORKS
+	ccr0 |= CCR0_NC1 | CCR0_BARB;
+#else
+	ccr0 |= CCR0_NC1;
+#endif
+	write_cyrix_reg(CCR0, ccr0);
+
+	/* Clear non-cacheable region. */
+	write_cyrix_reg(NCR1+2, NCR_SIZE_0K);
+	write_cyrix_reg(NCR2+2, NCR_SIZE_0K);
+	write_cyrix_reg(NCR3+2, NCR_SIZE_0K);
+	write_cyrix_reg(NCR4+2, NCR_SIZE_0K);
+
+	write_cyrix_reg(0, 0);	/* dummy write */
+
+	/* Enable caching in CR0. */
+	load_cr0(rcr0() & ~(CR0_CD | CR0_NW));	/* CD = 0 and NW = 0 */
+	invd();
+#endif /* !CYRIX_CACHE_WORKS */
+	write_eflags(eflags);
+}
+
+
+/*
+ * Cyrix 5x86
+ */
+static void
+init_5x86(void)
+{
+	u_long	eflags;
+	u_char	ccr2, ccr3, ccr4, pcr0;
+
+	eflags = read_eflags();
+	disable_intr();
+
+	load_cr0(rcr0() | CR0_CD | CR0_NW);
+	wbinvd();
+
+	(void)read_cyrix_reg(CCR3);		/* dummy */
+
+	/* Initialize CCR2. */
+	ccr2 = read_cyrix_reg(CCR2);
+	ccr2 |= CCR2_WB;
+#ifdef CPU_SUSP_HLT
+	ccr2 |= CCR2_SUSP_HLT;
+#else
+	ccr2 &= ~CCR2_SUSP_HLT;
+#endif
+	ccr2 |= CCR2_WT1;
+	write_cyrix_reg(CCR2, ccr2);
+
+	/* Initialize CCR4. */
+	ccr3 = read_cyrix_reg(CCR3);
+	write_cyrix_reg(CCR3, CCR3_MAPEN0);
+
+	ccr4 = read_cyrix_reg(CCR4);
+	ccr4 |= CCR4_DTE;
+	ccr4 |= CCR4_MEM;
+#ifdef CPU_FASTER_5X86_FPU
+	ccr4 |= CCR4_FASTFPE;
+#else
+	ccr4 &= ~CCR4_FASTFPE;
+#endif
+	ccr4 &= ~CCR4_IOMASK;
+	/********************************************************************
+	 * WARNING: The "BIOS Writers Guide" mentions that I/O recovery time
+	 * should be 0 for errata fix.
+	 ********************************************************************/
+#ifdef CPU_IORT
+	ccr4 |= CPU_IORT & CCR4_IOMASK;
+#endif
+	write_cyrix_reg(CCR4, ccr4);
+
+	/* Initialize PCR0. */
+	/****************************************************************
+	 * WARNING: RSTK_EN and LOOP_EN could make your system unstable.
+	 * BTB_EN might make your system unstable.
+	 ****************************************************************/
+	pcr0 = read_cyrix_reg(PCR0);
+#ifdef CPU_RSTK_EN
+	pcr0 |= PCR0_RSTK;
+#else
+	pcr0 &= ~PCR0_RSTK;
+#endif
+#ifdef CPU_BTB_EN
+	pcr0 |= PCR0_BTB;
+#else
+	pcr0 &= ~PCR0_BTB;
+#endif
+#ifdef CPU_LOOP_EN
+	pcr0 |= PCR0_LOOP;
+#else
+	pcr0 &= ~PCR0_LOOP;
+#endif
+
+	/****************************************************************
+	 * WARNING: if you use a memory mapped I/O device, don't use
+	 * DISABLE_5X86_LSSER option, which may reorder memory mapped
+	 * I/O access.
+	 * IF YOUR MOTHERBOARD HAS PCI BUS, DON'T DISABLE LSSER.
+	 ****************************************************************/
+#ifdef CPU_DISABLE_5X86_LSSER
+	pcr0 &= ~PCR0_LSSER;
+#else
+	pcr0 |= PCR0_LSSER;
+#endif
+	write_cyrix_reg(PCR0, pcr0);
+
+	/* Restore CCR3. */
+	write_cyrix_reg(CCR3, ccr3);
+
+	(void)read_cyrix_reg(0x80);		/* dummy */
+
+	/* Unlock NW bit in CR0. */
+	write_cyrix_reg(CCR2, read_cyrix_reg(CCR2) & ~CCR2_LOCK_NW);
+	load_cr0((rcr0() & ~CR0_CD) | CR0_NW);	/* CD = 0, NW = 1 */
+	/* Lock NW bit in CR0. */
+	write_cyrix_reg(CCR2, read_cyrix_reg(CCR2) | CCR2_LOCK_NW);
+
+	write_eflags(eflags);
+}
+
+#ifdef CPU_I486_ON_386
+/*
+ * There are i486 based upgrade products for i386 machines.
+ * In this case, BIOS doesn't enables CPU cache.
+ */
+void
+init_i486_on_386(void)
+{
+	u_long	eflags;
+
+#if defined(PC98) && !defined(CPU_UPGRADE_HW_CACHE)
+	need_post_dma_flush = 1;
+#endif
+
+	eflags = read_eflags();
+	disable_intr();
+
+	load_cr0(rcr0() & ~(CR0_CD | CR0_NW));	/* CD = 0, NW = 0 */
+
+	write_elfags(eflags);
+}
+#endif
+
+/*
+ * Cyrix 6x86
+ *
+ * XXX - What should I do here?  Please let me know.
+ */
+static void
+init_6x86(void)
+{
+	u_long	eflags;
+	u_char	ccr3, ccr4;
+
+	eflags = read_eflags();
+	disable_intr();
+
+	load_cr0(rcr0() | CR0_CD | CR0_NW);
+	wbinvd();
+
+	/* Initialize CCR0. */
+	write_cyrix_reg(CCR0, read_cyrix_reg(CCR0) | CCR0_NC1);
+
+	/* Initialize CCR2. */
+#ifdef CPU_SUSP_HLT
+	write_cyrix_reg(CCR2, read_cyrix_reg(CCR2) | CCR2_SUSP_HLT);
+#else
+	write_cyrix_reg(CCR2, read_cyrix_reg(CCR2) & ~CCR2_SUSP_HLT);
+#endif
+
+	ccr3 = read_cyrix_reg(CCR3);
+	write_cyrix_reg(CCR3, CCR3_MAPEN0);
+
+	/* Initialize CCR4. */
+	ccr4 = read_cyrix_reg(CCR4);
+	ccr4 |= CCR4_DTE;
+	ccr4 &= ~CCR4_IOMASK;
+#ifdef CPU_IORT
+	write_cyrix_reg(CCR4, ccr4 | (CPU_IORT & CCR4_IOMASK));
+#else
+	write_cyrix_reg(CCR4, ccr4 | 7);
+#endif
+
+	/* Restore CCR3. */
+	write_cyrix_reg(CCR3, ccr3);
+
+	/* Unlock NW bit in CR0. */
+	write_cyrix_reg(CCR2, read_cyrix_reg(CCR2) & ~CCR2_LOCK_NW);
+
+	/*
+	 * Earlier revision of the 6x86 CPU could crash the system if
+	 * L1 cache is in write-back mode.
+	 */
+	if ((cyrix_did & 0xff00) > 0x1600)
+		load_cr0(rcr0() & ~(CR0_CD | CR0_NW));	/* CD = 0 and NW = 0 */
+	else {
+		/* Revision 2.6 and lower. */
+#ifdef CYRIX_CACHE_REALLY_WORKS
+		load_cr0(rcr0() & ~(CR0_CD | CR0_NW));	/* CD = 0 and NW = 0 */
+#else
+		load_cr0((rcr0() & ~CR0_CD) | CR0_NW);	/* CD = 0 and NW = 1 */
+#endif
+	}
+
+	/* Lock NW bit in CR0. */
+	write_cyrix_reg(CCR2, read_cyrix_reg(CCR2) | CCR2_LOCK_NW);
+
+	write_eflags(eflags);
+}
+#endif /* I486_CPU */
+
+void
+initializecpu(void)
+{
+
+	switch (cpu) {
+#ifdef I486_CPU
+	case CPU_BLUE:
+		init_bluelightning();
+		break;
+	case CPU_486DLC:
+		init_486dlc();
+		break;
+	case CPU_M1SC:
+		init_5x86();
+		break;
+#ifdef CPU_I486_ON_386
+	case CPU_486:
+		init_i486_on_386();
+		break;
+#endif
+	case CPU_M1:
+		init_6x86();
+		break;
+#endif /* I486_CPU */
+	default:
+		break;
+	}
+
+#if defined(PC98) && !defined(CPU_UPGRADE_HW_CACHE)
+	/*
+	 * OS should flush L1 cahce by itself because no PC-98 supports
+	 * non-Intel CPUs.  Use wbinvd instruction before DMA transfer
+	 * when need_pre_dma_flush = 1, use invd instruction after DMA
+	 * transfer when need_post_dma_flush = 1.  If your CPU upgrade
+	 * product support hardware cache control, you can add
+	 * UPGRADE_CPU_HW_CACHE option in your kernel configuration file.
+	 * This option elminate unneeded cache flush instruction.
+	 */
+	if (strcmp(cpu_vendor, "CyrixInstead") == 0) {
+		switch (cpu) {
+#ifdef I486_CPU
+		case CPU_486DLC:
+			need_post_dma_flush = 1;
+			break;
+		case CPU_M1SC:
+			need_pre_dma_flush = 1;
+			break;
+#endif
+		default:
+			break;
+		}
+	} else if (strcmp(cpu_vendor, "AuthenticAMD") == 0) {
+		switch (cpu_id & 0xFF0) {
+		case 0x470:		/* Enhanced Am486DX2 WB */
+		case 0x490:		/* Enhanced Am486DX4 WB */
+		case 0x4F0:		/* Am5x86 WB */
+			need_pre_dma_flush = 1;
+			break;
+		}
+	} else if (strcmp(cpu_vendor, "IBM") == 0) {
+		need_post_dma_flush = 1;
+	} else {
+#ifdef CPU_I486_ON_386
+		need_pre_dma_flush = 1;
+#endif
+	}
+#endif /* PC98 && !UPGRADE_CPU_HW_CACHE */
+}
+
+#include "opt_ddb.h"
+#ifdef DDB
+#include <ddb/ddb.h>
+
+DB_SHOW_COMMAND(cyrixreg, cyrixreg)
+{
+	u_long	eflags;
+	u_int	cr0;
+	u_char	ccr0, ccr1, ccr2, ccr3, ccr4, ccr5, pcr0;
+
+	cr0 = rcr0();
+	if (strcmp(cpu_vendor,"CyrixInstead") == 0) {
+		eflags = read_eflags();
+		disable_intr();
+
+
+		if (cpu != CPU_M1SC) {
+			ccr0 = read_cyrix_reg(CCR0);
+		}
+		ccr1 = read_cyrix_reg(CCR1);
+		ccr2 = read_cyrix_reg(CCR2);
+		ccr3 = read_cyrix_reg(CCR3);
+		if ((cpu == CPU_M1SC) || (cpu == CPU_M1)) {
+			write_cyrix_reg(CCR3, CCR3_MAPEN0);
+			ccr4 = read_cyrix_reg(CCR4);
+			if (cpu == CPU_M1)
+				ccr5 = read_cyrix_reg(CCR5);
+			else
+				pcr0 = read_cyrix_reg(PCR0);
+			write_cyrix_reg(CCR3, ccr3);		/* Restore CCR3. */
+		}
+		write_eflags(eflags);
+
+		if (cpu != CPU_M1SC)
+			printf("CCR0=%x, ", (u_int)ccr0);
+
+		printf("CCR1=%x, CCR2=%x, CCR3=%x",
+			(u_int)ccr1, (u_int)ccr2, (u_int)ccr3);
+		if ((cpu == CPU_M1SC) || (cpu == CPU_M1)) {
+			printf(", CCR4=%x, ", (u_int)ccr4);
+			if (cpu == CPU_M1)
+				printf("CCR5=%x\n", ccr5);
+			else
+				printf("PCR0=%x\n", pcr0);
+		}
+	}
+	printf("CR0=%x\n", cr0);
+}
+#endif /* DDB */
diff --git a/sys/i386/i386/initcpu.c b/sys/i386/i386/initcpu.c
new file mode 100644
index 000000000000..482f0a2c02d7
--- /dev/null
+++ b/sys/i386/i386/initcpu.c
@@ -0,0 +1,444 @@
+/*
+ * Copyright (c) KATO Takenori, 1997.
+ * 
+ * All rights reserved.  Unpublished rights reserved under the copyright
+ * laws of Japan.
+ * 
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer as
+ *    the first lines of this file unmodified.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ *		$Id$
+ */
+
+#include "opt_cpu.h"
+
+#include <sys/param.h>
+#include <sys/kernel.h>
+#include <sys/systm.h>
+
+#include <machine/cpu.h>
+#include <machine/cputypes.h>
+#include <machine/md_var.h>
+#include <machine/specialreg.h>
+
+void initializecpu(void);
+#ifdef I486_CPU
+static void init_5x86(void);
+static void init_bluelightning(void);
+static void init_486dlc(void);
+#ifdef CPU_I486_ON_386
+static void init_i486_on_386(void);
+#endif
+static void init_6x86(void);
+#endif /* I486_CPU */
+
+#ifdef I486_CPU
+/*
+ * IBM Blue Lightning
+ */
+static void
+init_bluelightning(void)
+{
+	u_long	eflags;
+
+#if defined(PC98) && !defined(CPU_UPGRADE_HW_CACHE)
+	need_post_dma_flush = 1;
+#endif
+
+	eflags = read_eflags();
+	disable_intr();
+
+	load_cr0(rcr0() | CR0_CD | CR0_NW);
+	invd();
+
+#ifdef CPU_BLUELIGHTNING_FPU_OP_CACHE
+	wrmsr(0x1000, 0x9c92LL);	/* FP operand can be cacheable on Cyrix FPU */
+#else
+	wrmsr(0x1000, 0x1c92LL);	/* Intel FPU */
+#endif
+	/* Enables 13MB and 0-640KB cache. */
+	wrmsr(0x1001, (0xd0LL << 32) | 0x3ff);
+#ifdef CPU_BLUELIGHTNING_3X
+	wrmsr(0x1002, 0x04000000LL);	/* Enables triple-clock mode. */
+#else
+	wrmsr(0x1002, 0x03000000LL);	/* Enables double-clock mode. */
+#endif
+
+	/* Enable caching in CR0. */
+	load_cr0(rcr0() & ~(CR0_CD | CR0_NW));	/* CD = 0 and NW = 0 */
+	invd();
+	write_eflags(eflags);
+}
+
+/*
+ * Cyrix 486 series
+ */
+static void
+init_486dlc(void)
+{
+	u_long	eflags;
+	u_char	ccr0;
+
+	eflags = read_eflags();
+	disable_intr();
+
+	load_cr0(rcr0() | CR0_CD | CR0_NW);
+	invd();
+
+	ccr0 = read_cyrix_reg(CCR0);
+#ifndef CYRIX_CACHE_WORKS
+	ccr0 |= CCR0_NC1 | CCR0_BARB;
+	write_cyrix_reg(CCR0, ccr0);
+	invd();
+#else
+	ccr0 &= ~CCR0_NC0;
+#ifndef CYRIX_CACHE_REALLY_WORKS
+	ccr0 |= CCR0_NC1 | CCR0_BARB;
+#else
+	ccr0 |= CCR0_NC1;
+#endif
+	write_cyrix_reg(CCR0, ccr0);
+
+	/* Clear non-cacheable region. */
+	write_cyrix_reg(NCR1+2, NCR_SIZE_0K);
+	write_cyrix_reg(NCR2+2, NCR_SIZE_0K);
+	write_cyrix_reg(NCR3+2, NCR_SIZE_0K);
+	write_cyrix_reg(NCR4+2, NCR_SIZE_0K);
+
+	write_cyrix_reg(0, 0);	/* dummy write */
+
+	/* Enable caching in CR0. */
+	load_cr0(rcr0() & ~(CR0_CD | CR0_NW));	/* CD = 0 and NW = 0 */
+	invd();
+#endif /* !CYRIX_CACHE_WORKS */
+	write_eflags(eflags);
+}
+
+
+/*
+ * Cyrix 5x86
+ */
+static void
+init_5x86(void)
+{
+	u_long	eflags;
+	u_char	ccr2, ccr3, ccr4, pcr0;
+
+	eflags = read_eflags();
+	disable_intr();
+
+	load_cr0(rcr0() | CR0_CD | CR0_NW);
+	wbinvd();
+
+	(void)read_cyrix_reg(CCR3);		/* dummy */
+
+	/* Initialize CCR2. */
+	ccr2 = read_cyrix_reg(CCR2);
+	ccr2 |= CCR2_WB;
+#ifdef CPU_SUSP_HLT
+	ccr2 |= CCR2_SUSP_HLT;
+#else
+	ccr2 &= ~CCR2_SUSP_HLT;
+#endif
+	ccr2 |= CCR2_WT1;
+	write_cyrix_reg(CCR2, ccr2);
+
+	/* Initialize CCR4. */
+	ccr3 = read_cyrix_reg(CCR3);
+	write_cyrix_reg(CCR3, CCR3_MAPEN0);
+
+	ccr4 = read_cyrix_reg(CCR4);
+	ccr4 |= CCR4_DTE;
+	ccr4 |= CCR4_MEM;
+#ifdef CPU_FASTER_5X86_FPU
+	ccr4 |= CCR4_FASTFPE;
+#else
+	ccr4 &= ~CCR4_FASTFPE;
+#endif
+	ccr4 &= ~CCR4_IOMASK;
+	/********************************************************************
+	 * WARNING: The "BIOS Writers Guide" mentions that I/O recovery time
+	 * should be 0 for errata fix.
+	 ********************************************************************/
+#ifdef CPU_IORT
+	ccr4 |= CPU_IORT & CCR4_IOMASK;
+#endif
+	write_cyrix_reg(CCR4, ccr4);
+
+	/* Initialize PCR0. */
+	/****************************************************************
+	 * WARNING: RSTK_EN and LOOP_EN could make your system unstable.
+	 * BTB_EN might make your system unstable.
+	 ****************************************************************/
+	pcr0 = read_cyrix_reg(PCR0);
+#ifdef CPU_RSTK_EN
+	pcr0 |= PCR0_RSTK;
+#else
+	pcr0 &= ~PCR0_RSTK;
+#endif
+#ifdef CPU_BTB_EN
+	pcr0 |= PCR0_BTB;
+#else
+	pcr0 &= ~PCR0_BTB;
+#endif
+#ifdef CPU_LOOP_EN
+	pcr0 |= PCR0_LOOP;
+#else
+	pcr0 &= ~PCR0_LOOP;
+#endif
+
+	/****************************************************************
+	 * WARNING: if you use a memory mapped I/O device, don't use
+	 * DISABLE_5X86_LSSER option, which may reorder memory mapped
+	 * I/O access.
+	 * IF YOUR MOTHERBOARD HAS PCI BUS, DON'T DISABLE LSSER.
+	 ****************************************************************/
+#ifdef CPU_DISABLE_5X86_LSSER
+	pcr0 &= ~PCR0_LSSER;
+#else
+	pcr0 |= PCR0_LSSER;
+#endif
+	write_cyrix_reg(PCR0, pcr0);
+
+	/* Restore CCR3. */
+	write_cyrix_reg(CCR3, ccr3);
+
+	(void)read_cyrix_reg(0x80);		/* dummy */
+
+	/* Unlock NW bit in CR0. */
+	write_cyrix_reg(CCR2, read_cyrix_reg(CCR2) & ~CCR2_LOCK_NW);
+	load_cr0((rcr0() & ~CR0_CD) | CR0_NW);	/* CD = 0, NW = 1 */
+	/* Lock NW bit in CR0. */
+	write_cyrix_reg(CCR2, read_cyrix_reg(CCR2) | CCR2_LOCK_NW);
+
+	write_eflags(eflags);
+}
+
+#ifdef CPU_I486_ON_386
+/*
+ * There are i486 based upgrade products for i386 machines.
+ * In this case, BIOS doesn't enables CPU cache.
+ */
+void
+init_i486_on_386(void)
+{
+	u_long	eflags;
+
+#if defined(PC98) && !defined(CPU_UPGRADE_HW_CACHE)
+	need_post_dma_flush = 1;
+#endif
+
+	eflags = read_eflags();
+	disable_intr();
+
+	load_cr0(rcr0() & ~(CR0_CD | CR0_NW));	/* CD = 0, NW = 0 */
+
+	write_elfags(eflags);
+}
+#endif
+
+/*
+ * Cyrix 6x86
+ *
+ * XXX - What should I do here?  Please let me know.
+ */
+static void
+init_6x86(void)
+{
+	u_long	eflags;
+	u_char	ccr3, ccr4;
+
+	eflags = read_eflags();
+	disable_intr();
+
+	load_cr0(rcr0() | CR0_CD | CR0_NW);
+	wbinvd();
+
+	/* Initialize CCR0. */
+	write_cyrix_reg(CCR0, read_cyrix_reg(CCR0) | CCR0_NC1);
+
+	/* Initialize CCR2. */
+#ifdef CPU_SUSP_HLT
+	write_cyrix_reg(CCR2, read_cyrix_reg(CCR2) | CCR2_SUSP_HLT);
+#else
+	write_cyrix_reg(CCR2, read_cyrix_reg(CCR2) & ~CCR2_SUSP_HLT);
+#endif
+
+	ccr3 = read_cyrix_reg(CCR3);
+	write_cyrix_reg(CCR3, CCR3_MAPEN0);
+
+	/* Initialize CCR4. */
+	ccr4 = read_cyrix_reg(CCR4);
+	ccr4 |= CCR4_DTE;
+	ccr4 &= ~CCR4_IOMASK;
+#ifdef CPU_IORT
+	write_cyrix_reg(CCR4, ccr4 | (CPU_IORT & CCR4_IOMASK));
+#else
+	write_cyrix_reg(CCR4, ccr4 | 7);
+#endif
+
+	/* Restore CCR3. */
+	write_cyrix_reg(CCR3, ccr3);
+
+	/* Unlock NW bit in CR0. */
+	write_cyrix_reg(CCR2, read_cyrix_reg(CCR2) & ~CCR2_LOCK_NW);
+
+	/*
+	 * Earlier revision of the 6x86 CPU could crash the system if
+	 * L1 cache is in write-back mode.
+	 */
+	if ((cyrix_did & 0xff00) > 0x1600)
+		load_cr0(rcr0() & ~(CR0_CD | CR0_NW));	/* CD = 0 and NW = 0 */
+	else {
+		/* Revision 2.6 and lower. */
+#ifdef CYRIX_CACHE_REALLY_WORKS
+		load_cr0(rcr0() & ~(CR0_CD | CR0_NW));	/* CD = 0 and NW = 0 */
+#else
+		load_cr0((rcr0() & ~CR0_CD) | CR0_NW);	/* CD = 0 and NW = 1 */
+#endif
+	}
+
+	/* Lock NW bit in CR0. */
+	write_cyrix_reg(CCR2, read_cyrix_reg(CCR2) | CCR2_LOCK_NW);
+
+	write_eflags(eflags);
+}
+#endif /* I486_CPU */
+
+void
+initializecpu(void)
+{
+
+	switch (cpu) {
+#ifdef I486_CPU
+	case CPU_BLUE:
+		init_bluelightning();
+		break;
+	case CPU_486DLC:
+		init_486dlc();
+		break;
+	case CPU_M1SC:
+		init_5x86();
+		break;
+#ifdef CPU_I486_ON_386
+	case CPU_486:
+		init_i486_on_386();
+		break;
+#endif
+	case CPU_M1:
+		init_6x86();
+		break;
+#endif /* I486_CPU */
+	default:
+		break;
+	}
+
+#if defined(PC98) && !defined(CPU_UPGRADE_HW_CACHE)
+	/*
+	 * OS should flush L1 cahce by itself because no PC-98 supports
+	 * non-Intel CPUs.  Use wbinvd instruction before DMA transfer
+	 * when need_pre_dma_flush = 1, use invd instruction after DMA
+	 * transfer when need_post_dma_flush = 1.  If your CPU upgrade
+	 * product support hardware cache control, you can add
+	 * UPGRADE_CPU_HW_CACHE option in your kernel configuration file.
+	 * This option elminate unneeded cache flush instruction.
+	 */
+	if (strcmp(cpu_vendor, "CyrixInstead") == 0) {
+		switch (cpu) {
+#ifdef I486_CPU
+		case CPU_486DLC:
+			need_post_dma_flush = 1;
+			break;
+		case CPU_M1SC:
+			need_pre_dma_flush = 1;
+			break;
+#endif
+		default:
+			break;
+		}
+	} else if (strcmp(cpu_vendor, "AuthenticAMD") == 0) {
+		switch (cpu_id & 0xFF0) {
+		case 0x470:		/* Enhanced Am486DX2 WB */
+		case 0x490:		/* Enhanced Am486DX4 WB */
+		case 0x4F0:		/* Am5x86 WB */
+			need_pre_dma_flush = 1;
+			break;
+		}
+	} else if (strcmp(cpu_vendor, "IBM") == 0) {
+		need_post_dma_flush = 1;
+	} else {
+#ifdef CPU_I486_ON_386
+		need_pre_dma_flush = 1;
+#endif
+	}
+#endif /* PC98 && !UPGRADE_CPU_HW_CACHE */
+}
+
+#include "opt_ddb.h"
+#ifdef DDB
+#include <ddb/ddb.h>
+
+DB_SHOW_COMMAND(cyrixreg, cyrixreg)
+{
+	u_long	eflags;
+	u_int	cr0;
+	u_char	ccr0, ccr1, ccr2, ccr3, ccr4, ccr5, pcr0;
+
+	cr0 = rcr0();
+	if (strcmp(cpu_vendor,"CyrixInstead") == 0) {
+		eflags = read_eflags();
+		disable_intr();
+
+
+		if (cpu != CPU_M1SC) {
+			ccr0 = read_cyrix_reg(CCR0);
+		}
+		ccr1 = read_cyrix_reg(CCR1);
+		ccr2 = read_cyrix_reg(CCR2);
+		ccr3 = read_cyrix_reg(CCR3);
+		if ((cpu == CPU_M1SC) || (cpu == CPU_M1)) {
+			write_cyrix_reg(CCR3, CCR3_MAPEN0);
+			ccr4 = read_cyrix_reg(CCR4);
+			if (cpu == CPU_M1)
+				ccr5 = read_cyrix_reg(CCR5);
+			else
+				pcr0 = read_cyrix_reg(PCR0);
+			write_cyrix_reg(CCR3, ccr3);		/* Restore CCR3. */
+		}
+		write_eflags(eflags);
+
+		if (cpu != CPU_M1SC)
+			printf("CCR0=%x, ", (u_int)ccr0);
+
+		printf("CCR1=%x, CCR2=%x, CCR3=%x",
+			(u_int)ccr1, (u_int)ccr2, (u_int)ccr3);
+		if ((cpu == CPU_M1SC) || (cpu == CPU_M1)) {
+			printf(", CCR4=%x, ", (u_int)ccr4);
+			if (cpu == CPU_M1)
+				printf("CCR5=%x\n", ccr5);
+			else
+				printf("PCR0=%x\n", pcr0);
+		}
+	}
+	printf("CR0=%x\n", cr0);
+}
+#endif /* DDB */