FreeBSD-5.3/sys/i386/i386/initcpu.c
/*-
* Copyright (c) KATO Takenori, 1997, 1998.
*
* 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 Unpublished rights reserved under the copyright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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD: src/sys/i386/i386/initcpu.c,v 1.49 2003/11/10 15:48:30 jhb Exp $");
#include "opt_cpu.h"
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/systm.h>
#include <sys/sysctl.h>
#include <machine/cputypes.h>
#include <machine/md_var.h>
#include <machine/specialreg.h>
#if !defined(CPU_ENABLE_SSE) && defined(I686_CPU)
#define CPU_ENABLE_SSE
#endif
#if defined(CPU_DISABLE_SSE)
#undef CPU_ENABLE_SSE
#endif
void initializecpu(void);
#if defined(I586_CPU) && defined(CPU_WT_ALLOC)
void enable_K5_wt_alloc(void);
void enable_K6_wt_alloc(void);
void enable_K6_2_wt_alloc(void);
#endif
#ifdef I486_CPU
static void init_5x86(void);
static void init_bluelightning(void);
static void init_486dlc(void);
static void init_cy486dx(void);
#ifdef CPU_I486_ON_386
static void init_i486_on_386(void);
#endif
static void init_6x86(void);
#endif /* I486_CPU */
#ifdef I686_CPU
static void init_6x86MX(void);
static void init_ppro(void);
static void init_mendocino(void);
#endif
static int hw_instruction_sse;
SYSCTL_INT(_hw, OID_AUTO, instruction_sse, CTLFLAG_RD,
&hw_instruction_sse, 0, "SIMD/MMX2 instructions available in CPU");
/* Must *NOT* be BSS or locore will bzero these after setting them */
int cpu = 0; /* Are we 386, 386sx, 486, etc? */
u_int cpu_feature = 0; /* Feature flags */
u_int cpu_high = 0; /* Highest arg to CPUID */
u_int cpu_id = 0; /* Stepping ID */
u_int cpu_procinfo = 0; /* HyperThreading Info / Brand Index / CLFUSH */
char cpu_vendor[20] = ""; /* CPU Origin code */
#ifdef CPU_ENABLE_SSE
u_int cpu_fxsr; /* SSE enabled */
#endif
#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 486SLC/DLC/SR/DR series
*/
static void
init_486dlc(void)
{
u_long eflags;
u_char ccr0;
eflags = read_eflags();
disable_intr();
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
#ifdef CPU_DIRECT_MAPPED_CACHE
ccr0 |= CCR0_CO; /* Direct mapped mode. */
#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 486S/DX series
*/
static void
init_cy486dx(void)
{
u_long eflags;
u_char ccr2;
eflags = read_eflags();
disable_intr();
invd();
ccr2 = read_cyrix_reg(CCR2);
#ifdef CPU_SUSP_HLT
ccr2 |= CCR2_SUSP_HLT;
#endif
#ifdef PC98
/* Enables WB cache interface pin and Lock NW bit in CR0. */
ccr2 |= CCR2_WB | CCR2_LOCK_NW;
/* Unlock NW bit in CR0. */
write_cyrix_reg(CCR2, ccr2 & ~CCR2_LOCK_NW);
load_cr0((rcr0() & ~CR0_CD) | CR0_NW); /* CD = 0, NW = 1 */
#endif
write_cyrix_reg(CCR2, ccr2);
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.
*/
static 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_eflags(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 CCR1. */
#ifdef CPU_CYRIX_NO_LOCK
write_cyrix_reg(CCR1, read_cyrix_reg(CCR1) | CCR1_NO_LOCK);
#else
write_cyrix_reg(CCR1, read_cyrix_reg(CCR1) & ~CCR1_NO_LOCK);
#endif
/* 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
/* Initialize CCR5. */
#ifdef CPU_WT_ALLOC
write_cyrix_reg(CCR5, read_cyrix_reg(CCR5) | CCR5_WT_ALLOC);
#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 */
#ifdef I686_CPU
/*
* Cyrix 6x86MX (code-named M2)
*
* XXX - What should I do here? Please let me know.
*/
static void
init_6x86MX(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 CCR1. */
#ifdef CPU_CYRIX_NO_LOCK
write_cyrix_reg(CCR1, read_cyrix_reg(CCR1) | CCR1_NO_LOCK);
#else
write_cyrix_reg(CCR1, read_cyrix_reg(CCR1) & ~CCR1_NO_LOCK);
#endif
/* 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_IOMASK;
#ifdef CPU_IORT
write_cyrix_reg(CCR4, ccr4 | (CPU_IORT & CCR4_IOMASK));
#else
write_cyrix_reg(CCR4, ccr4 | 7);
#endif
/* Initialize CCR5. */
#ifdef CPU_WT_ALLOC
write_cyrix_reg(CCR5, read_cyrix_reg(CCR5) | CCR5_WT_ALLOC);
#endif
/* Restore CCR3. */
write_cyrix_reg(CCR3, ccr3);
/* 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 and NW = 0 */
/* Lock NW bit in CR0. */
write_cyrix_reg(CCR2, read_cyrix_reg(CCR2) | CCR2_LOCK_NW);
write_eflags(eflags);
}
static void
init_ppro(void)
{
u_int64_t apicbase;
/*
* Local APIC should be disabled if it is not going to be used.
*/
apicbase = rdmsr(MSR_APICBASE);
apicbase &= ~APICBASE_ENABLED;
wrmsr(MSR_APICBASE, apicbase);
}
/*
* Initialize BBL_CR_CTL3 (Control register 3: used to configure the
* L2 cache).
*/
static void
init_mendocino(void)
{
#ifdef CPU_PPRO2CELERON
u_long eflags;
u_int64_t bbl_cr_ctl3;
eflags = read_eflags();
disable_intr();
load_cr0(rcr0() | CR0_CD | CR0_NW);
wbinvd();
bbl_cr_ctl3 = rdmsr(MSR_BBL_CR_CTL3);
/* If the L2 cache is configured, do nothing. */
if (!(bbl_cr_ctl3 & 1)) {
bbl_cr_ctl3 = 0x134052bLL;
/* Set L2 Cache Latency (Default: 5). */
#ifdef CPU_CELERON_L2_LATENCY
#if CPU_L2_LATENCY > 15
#error invalid CPU_L2_LATENCY.
#endif
bbl_cr_ctl3 |= CPU_L2_LATENCY << 1;
#else
bbl_cr_ctl3 |= 5 << 1;
#endif
wrmsr(MSR_BBL_CR_CTL3, bbl_cr_ctl3);
}
load_cr0(rcr0() & ~(CR0_CD | CR0_NW));
write_eflags(eflags);
#endif /* CPU_PPRO2CELERON */
}
#endif /* I686_CPU */
/*
* Initialize CR4 (Control register 4) to enable SSE instructions.
*/
void
enable_sse(void)
{
#if defined(CPU_ENABLE_SSE)
if ((cpu_feature & CPUID_XMM) && (cpu_feature & CPUID_FXSR)) {
load_cr4(rcr4() | CR4_FXSR | CR4_XMM);
cpu_fxsr = hw_instruction_sse = 1;
}
#endif
}
void
initializecpu(void)
{
switch (cpu) {
#ifdef I486_CPU
case CPU_BLUE:
init_bluelightning();
break;
case CPU_486DLC:
init_486dlc();
break;
case CPU_CY486DX:
init_cy486dx();
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 */
#ifdef I686_CPU
case CPU_M2:
init_6x86MX();
break;
case CPU_686:
if (strcmp(cpu_vendor, "GenuineIntel") == 0) {
switch (cpu_id & 0xff0) {
case 0x610:
init_ppro();
break;
case 0x660:
init_mendocino();
break;
}
} else if (strcmp(cpu_vendor, "AuthenticAMD") == 0) {
#if defined(I686_CPU) && defined(CPU_ATHLON_SSE_HACK)
/*
* Sometimes the BIOS doesn't enable SSE instructions.
* According to AMD document 20734, the mobile
* Duron, the (mobile) Athlon 4 and the Athlon MP
* support SSE. These correspond to cpu_id 0x66X
* or 0x67X.
*/
if ((cpu_feature & CPUID_XMM) == 0 &&
((cpu_id & ~0xf) == 0x660 ||
(cpu_id & ~0xf) == 0x670 ||
(cpu_id & ~0xf) == 0x680)) {
u_int regs[4];
wrmsr(0xC0010015, rdmsr(0xC0010015) & ~0x08000);
do_cpuid(1, regs);
cpu_feature = regs[3];
}
#endif
}
break;
#endif
default:
break;
}
enable_sse();
#if defined(PC98) && !defined(CPU_UPGRADE_HW_CACHE)
/*
* OS should flush L1 cache 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 supports hardware cache control, you can add the
* CPU_UPGRADE_HW_CACHE option in your kernel configuration file.
* This option eliminates unneeded cache flush instruction(s).
*/
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;
case CPU_CY486DX:
need_pre_dma_flush = 1;
#ifdef CPU_I486_ON_386
need_post_dma_flush = 1;
#endif
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 && !CPU_UPGRADE_HW_CACHE */
}
#if defined(I586_CPU) && defined(CPU_WT_ALLOC)
/*
* Enable write allocate feature of AMD processors.
* Following two functions require the Maxmem variable being set.
*/
void
enable_K5_wt_alloc(void)
{
u_int64_t msr;
register_t savecrit;
/*
* Write allocate is supported only on models 1, 2, and 3, with
* a stepping of 4 or greater.
*/
if (((cpu_id & 0xf0) > 0) && ((cpu_id & 0x0f) > 3)) {
savecrit = intr_disable();
msr = rdmsr(0x83); /* HWCR */
wrmsr(0x83, msr & !(0x10));
/*
* We have to tell the chip where the top of memory is,
* since video cards could have frame bufferes there,
* memory-mapped I/O could be there, etc.
*/
if(Maxmem > 0)
msr = Maxmem / 16;
else
msr = 0;
msr |= AMD_WT_ALLOC_TME | AMD_WT_ALLOC_FRE;
#ifdef PC98
if (!(inb(0x43b) & 4)) {
wrmsr(0x86, 0x0ff00f0);
msr |= AMD_WT_ALLOC_PRE;
}
#else
/*
* There is no way to know wheter 15-16M hole exists or not.
* Therefore, we disable write allocate for this range.
*/
wrmsr(0x86, 0x0ff00f0);
msr |= AMD_WT_ALLOC_PRE;
#endif
wrmsr(0x85, msr);
msr=rdmsr(0x83);
wrmsr(0x83, msr|0x10); /* enable write allocate */
intr_restore(savecrit);
}
}
void
enable_K6_wt_alloc(void)
{
quad_t size;
u_int64_t whcr;
u_long eflags;
eflags = read_eflags();
disable_intr();
wbinvd();
#ifdef CPU_DISABLE_CACHE
/*
* Certain K6-2 box becomes unstable when write allocation is
* enabled.
*/
/*
* The AMD-K6 processer provides the 64-bit Test Register 12(TR12),
* but only the Cache Inhibit(CI) (bit 3 of TR12) is suppported.
* All other bits in TR12 have no effect on the processer's operation.
* The I/O Trap Restart function (bit 9 of TR12) is always enabled
* on the AMD-K6.
*/
wrmsr(0x0000000e, (u_int64_t)0x0008);
#endif
/* Don't assume that memory size is aligned with 4M. */
if (Maxmem > 0)
size = ((Maxmem >> 8) + 3) >> 2;
else
size = 0;
/* Limit is 508M bytes. */
if (size > 0x7f)
size = 0x7f;
whcr = (rdmsr(0xc0000082) & ~(0x7fLL << 1)) | (size << 1);
#if defined(PC98) || defined(NO_MEMORY_HOLE)
if (whcr & (0x7fLL << 1)) {
#ifdef PC98
/*
* If bit 2 of port 0x43b is 0, disable wrte allocate for the
* 15-16M range.
*/
if (!(inb(0x43b) & 4))
whcr &= ~0x0001LL;
else
#endif
whcr |= 0x0001LL;
}
#else
/*
* There is no way to know wheter 15-16M hole exists or not.
* Therefore, we disable write allocate for this range.
*/
whcr &= ~0x0001LL;
#endif
wrmsr(0x0c0000082, whcr);
write_eflags(eflags);
}
void
enable_K6_2_wt_alloc(void)
{
quad_t size;
u_int64_t whcr;
u_long eflags;
eflags = read_eflags();
disable_intr();
wbinvd();
#ifdef CPU_DISABLE_CACHE
/*
* Certain K6-2 box becomes unstable when write allocation is
* enabled.
*/
/*
* The AMD-K6 processer provides the 64-bit Test Register 12(TR12),
* but only the Cache Inhibit(CI) (bit 3 of TR12) is suppported.
* All other bits in TR12 have no effect on the processer's operation.
* The I/O Trap Restart function (bit 9 of TR12) is always enabled
* on the AMD-K6.
*/
wrmsr(0x0000000e, (u_int64_t)0x0008);
#endif
/* Don't assume that memory size is aligned with 4M. */
if (Maxmem > 0)
size = ((Maxmem >> 8) + 3) >> 2;
else
size = 0;
/* Limit is 4092M bytes. */
if (size > 0x3fff)
size = 0x3ff;
whcr = (rdmsr(0xc0000082) & ~(0x3ffLL << 22)) | (size << 22);
#if defined(PC98) || defined(NO_MEMORY_HOLE)
if (whcr & (0x3ffLL << 22)) {
#ifdef PC98
/*
* If bit 2 of port 0x43b is 0, disable wrte allocate for the
* 15-16M range.
*/
if (!(inb(0x43b) & 4))
whcr &= ~(1LL << 16);
else
#endif
whcr |= 1LL << 16;
}
#else
/*
* There is no way to know wheter 15-16M hole exists or not.
* Therefore, we disable write allocate for this range.
*/
whcr &= ~(1LL << 16);
#endif
wrmsr(0x0c0000082, whcr);
write_eflags(eflags);
}
#endif /* I585_CPU && CPU_WT_ALLOC */
#include "opt_ddb.h"
#ifdef DDB
#include <ddb/ddb.h>
DB_SHOW_COMMAND(cyrixreg, cyrixreg)
{
u_long eflags;
u_int cr0;
u_char ccr1, ccr2, ccr3;
u_char ccr0 = 0, ccr4 = 0, ccr5 = 0, pcr0 = 0;
cr0 = rcr0();
if (strcmp(cpu_vendor,"CyrixInstead") == 0) {
eflags = read_eflags();
disable_intr();
if ((cpu != CPU_M1SC) && (cpu != CPU_CY486DX)) {
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) || (cpu == CPU_M2)) {
write_cyrix_reg(CCR3, CCR3_MAPEN0);
ccr4 = read_cyrix_reg(CCR4);
if ((cpu == CPU_M1) || (cpu == CPU_M2))
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) && (cpu != CPU_CY486DX))
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) || (cpu == CPU_M2)) {
printf(", CCR4=%x, ", (u_int)ccr4);
if (cpu == CPU_M1SC)
printf("PCR0=%x\n", pcr0);
else
printf("CCR5=%x\n", ccr5);
}
}
printf("CR0=%x\n", cr0);
}
#endif /* DDB */