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#include <linux/init.h>
#include <linux/bitops.h>
#include <linux/delay.h>
#include <linux/pci.h>
#include <asm/dma.h>
#include <asm/io.h>
#include <asm/processor-cyrix.h>
#include <asm/processor-flags.h>
#include <asm/timer.h>
#include <asm/pci-direct.h>
#include <asm/tsc.h>
#include "cpu.h"
/*
* Read NSC/Cyrix DEVID registers (DIR) to get more detailed info. about the CPU
*/
static void __cpuinit __do_cyrix_devid(unsigned char *dir0, unsigned char *dir1)
{
unsigned char ccr2, ccr3;
/* we test for DEVID by checking whether CCR3 is writable */
ccr3 = getCx86(CX86_CCR3);
setCx86(CX86_CCR3, ccr3 ^ 0x80);
getCx86(0xc0); /* dummy to change bus */
if (getCx86(CX86_CCR3) == ccr3) { /* no DEVID regs. */
ccr2 = getCx86(CX86_CCR2);
setCx86(CX86_CCR2, ccr2 ^ 0x04);
getCx86(0xc0); /* dummy */
if (getCx86(CX86_CCR2) == ccr2) /* old Cx486SLC/DLC */
*dir0 = 0xfd;
else { /* Cx486S A step */
setCx86(CX86_CCR2, ccr2);
*dir0 = 0xfe;
}
} else {
setCx86(CX86_CCR3, ccr3); /* restore CCR3 */
/* read DIR0 and DIR1 CPU registers */
*dir0 = getCx86(CX86_DIR0);
*dir1 = getCx86(CX86_DIR1);
}
}
static void __cpuinit do_cyrix_devid(unsigned char *dir0, unsigned char *dir1)
{
unsigned long flags;
local_irq_save(flags);
__do_cyrix_devid(dir0, dir1);
local_irq_restore(flags);
}
/*
* Cx86_dir0_msb is a HACK needed by check_cx686_cpuid/slop in bugs.h in
* order to identify the Cyrix CPU model after we're out of setup.c
*
* Actually since bugs.h doesn't even reference this perhaps someone should
* fix the documentation ???
*/
static unsigned char Cx86_dir0_msb __cpuinitdata = 0;
static char Cx86_model[][9] __cpuinitdata = {
"Cx486", "Cx486", "5x86 ", "6x86", "MediaGX ", "6x86MX ",
"M II ", "Unknown"
};
static char Cx486_name[][5] __cpuinitdata = {
"SLC", "DLC", "SLC2", "DLC2", "SRx", "DRx",
"SRx2", "DRx2"
};
static char Cx486S_name[][4] __cpuinitdata = {
"S", "S2", "Se", "S2e"
};
static char Cx486D_name[][4] __cpuinitdata = {
"DX", "DX2", "?", "?", "?", "DX4"
};
static char Cx86_cb[] __cpuinitdata = "?.5x Core/Bus Clock";
static char cyrix_model_mult1[] __cpuinitdata = "12??43";
static char cyrix_model_mult2[] __cpuinitdata = "12233445";
/*
* Reset the slow-loop (SLOP) bit on the 686(L) which is set by some old
* BIOSes for compatibility with DOS games. This makes the udelay loop
* work correctly, and improves performance.
*
* FIXME: our newer udelay uses the tsc. We don't need to frob with SLOP
*/
static void __cpuinit check_cx686_slop(struct cpuinfo_x86 *c)
{
unsigned long flags;
if (Cx86_dir0_msb == 3) {
unsigned char ccr3, ccr5;
local_irq_save(flags);
ccr3 = getCx86(CX86_CCR3);
setCx86(CX86_CCR3, (ccr3 & 0x0f) | 0x10); /* enable MAPEN */
ccr5 = getCx86(CX86_CCR5);
if (ccr5 & 2)
setCx86(CX86_CCR5, ccr5 & 0xfd); /* reset SLOP */
setCx86(CX86_CCR3, ccr3); /* disable MAPEN */
local_irq_restore(flags);
if (ccr5 & 2) { /* possible wrong calibration done */
printk(KERN_INFO "Recalibrating delay loop with SLOP bit reset\n");
calibrate_delay();
c->loops_per_jiffy = loops_per_jiffy;
}
}
}
static void __cpuinit set_cx86_reorder(void)
{
u8 ccr3;
printk(KERN_INFO "Enable Memory access reorder on Cyrix/NSC processor.\n");
ccr3 = getCx86(CX86_CCR3);
setCx86(CX86_CCR3, (ccr3 & 0x0f) | 0x10); /* enable MAPEN */
/* Load/Store Serialize to mem access disable (=reorder it) */
setCx86(CX86_PCR0, getCx86(CX86_PCR0) & ~0x80);
/* set load/store serialize from 1GB to 4GB */
ccr3 |= 0xe0;
setCx86(CX86_CCR3, ccr3);
}
static void __cpuinit set_cx86_memwb(void)
{
printk(KERN_INFO "Enable Memory-Write-back mode on Cyrix/NSC processor.\n");
/* CCR2 bit 2: unlock NW bit */
setCx86(CX86_CCR2, getCx86(CX86_CCR2) & ~0x04);
/* set 'Not Write-through' */
write_cr0(read_cr0() | X86_CR0_NW);
/* CCR2 bit 2: lock NW bit and set WT1 */
setCx86(CX86_CCR2, getCx86(CX86_CCR2) | 0x14);
}
/*
* Configure later MediaGX and/or Geode processor.
*/
static void __cpuinit geode_configure(void)
{
unsigned long flags;
u8 ccr3;
local_irq_save(flags);
/* Suspend on halt power saving and enable #SUSP pin */
setCx86(CX86_CCR2, getCx86(CX86_CCR2) | 0x88);
ccr3 = getCx86(CX86_CCR3);
setCx86(CX86_CCR3, (ccr3 & 0x0f) | 0x10); /* enable MAPEN */
/* FPU fast, DTE cache, Mem bypass */
setCx86(CX86_CCR4, getCx86(CX86_CCR4) | 0x38);
setCx86(CX86_CCR3, ccr3); /* disable MAPEN */
set_cx86_memwb();
set_cx86_reorder();
local_irq_restore(flags);
}
static void __cpuinit early_init_cyrix(struct cpuinfo_x86 *c)
{
unsigned char dir0, dir0_msn, dir1 = 0;
__do_cyrix_devid(&dir0, &dir1);
dir0_msn = dir0 >> 4; /* identifies CPU "family" */
switch (dir0_msn) {
case 3: /* 6x86/6x86L */
/* Emulate MTRRs using Cyrix's ARRs. */
set_cpu_cap(c, X86_FEATURE_CYRIX_ARR);
break;
case 5: /* 6x86MX/M II */
/* Emulate MTRRs using Cyrix's ARRs. */
set_cpu_cap(c, X86_FEATURE_CYRIX_ARR);
break;
}
}
static void __cpuinit init_cyrix(struct cpuinfo_x86 *c)
{
unsigned char dir0, dir0_msn, dir0_lsn, dir1 = 0;
char *buf = c->x86_model_id;
const char *p = NULL;
/*
* Bit 31 in normal CPUID used for nonstandard 3DNow ID;
* 3DNow is IDd by bit 31 in extended CPUID (1*32+31) anyway
*/
clear_cpu_cap(c, 0*32+31);
/* Cyrix used bit 24 in extended (AMD) CPUID for Cyrix MMX extensions */
if (test_cpu_cap(c, 1*32+24)) {
clear_cpu_cap(c, 1*32+24);
set_cpu_cap(c, X86_FEATURE_CXMMX);
}
do_cyrix_devid(&dir0, &dir1);
check_cx686_slop(c);
Cx86_dir0_msb = dir0_msn = dir0 >> 4; /* identifies CPU "family" */
dir0_lsn = dir0 & 0xf; /* model or clock multiplier */
/* common case step number/rev -- exceptions handled below */
c->x86_model = (dir1 >> 4) + 1;
c->x86_mask = dir1 & 0xf;
/* Now cook; the original recipe is by Channing Corn, from Cyrix.
* We do the same thing for each generation: we work out
* the model, multiplier and stepping. Black magic included,
* to make the silicon step/rev numbers match the printed ones.
*/
switch (dir0_msn) {
unsigned char tmp;
case 0: /* Cx486SLC/DLC/SRx/DRx */
p = Cx486_name[dir0_lsn & 7];
break;
case 1: /* Cx486S/DX/DX2/DX4 */
p = (dir0_lsn & 8) ? Cx486D_name[dir0_lsn & 5]
: Cx486S_name[dir0_lsn & 3];
break;
case 2: /* 5x86 */
Cx86_cb[2] = cyrix_model_mult1[dir0_lsn & 5];
p = Cx86_cb+2;
break;
case 3: /* 6x86/6x86L */
Cx86_cb[1] = ' ';
Cx86_cb[2] = cyrix_model_mult1[dir0_lsn & 5];
if (dir1 > 0x21) { /* 686L */
Cx86_cb[0] = 'L';
p = Cx86_cb;
(c->x86_model)++;
} else /* 686 */
p = Cx86_cb+1;
/* Emulate MTRRs using Cyrix's ARRs. */
set_cpu_cap(c, X86_FEATURE_CYRIX_ARR);
/* 6x86's contain this bug */
c->coma_bug = 1;
break;
case
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