f8a363b83f
This CPU never made it into production. It went on to become the basis for the VIA Samuel. Signed-off-by: Dave Jones <davej@redhat.com>
473 lines
10 KiB
C
473 lines
10 KiB
C
#include <linux/kernel.h>
|
|
#include <linux/init.h>
|
|
#include <linux/bitops.h>
|
|
#include <asm/processor.h>
|
|
#include <asm/msr.h>
|
|
#include <asm/e820.h>
|
|
#include "cpu.h"
|
|
|
|
#ifdef CONFIG_X86_OOSTORE
|
|
|
|
static u32 __init power2(u32 x)
|
|
{
|
|
u32 s=1;
|
|
while(s<=x)
|
|
s<<=1;
|
|
return s>>=1;
|
|
}
|
|
|
|
|
|
/*
|
|
* Set up an actual MCR
|
|
*/
|
|
|
|
static void __init centaur_mcr_insert(int reg, u32 base, u32 size, int key)
|
|
{
|
|
u32 lo, hi;
|
|
|
|
hi = base & ~0xFFF;
|
|
lo = ~(size-1); /* Size is a power of 2 so this makes a mask */
|
|
lo &= ~0xFFF; /* Remove the ctrl value bits */
|
|
lo |= key; /* Attribute we wish to set */
|
|
wrmsr(reg+MSR_IDT_MCR0, lo, hi);
|
|
mtrr_centaur_report_mcr(reg, lo, hi); /* Tell the mtrr driver */
|
|
}
|
|
|
|
/*
|
|
* Figure what we can cover with MCR's
|
|
*
|
|
* Shortcut: We know you can't put 4Gig of RAM on a winchip
|
|
*/
|
|
|
|
static u32 __init ramtop(void) /* 16388 */
|
|
{
|
|
int i;
|
|
u32 top = 0;
|
|
u32 clip = 0xFFFFFFFFUL;
|
|
|
|
for (i = 0; i < e820.nr_map; i++) {
|
|
unsigned long start, end;
|
|
|
|
if (e820.map[i].addr > 0xFFFFFFFFUL)
|
|
continue;
|
|
/*
|
|
* Don't MCR over reserved space. Ignore the ISA hole
|
|
* we frob around that catastrophy already
|
|
*/
|
|
|
|
if (e820.map[i].type == E820_RESERVED)
|
|
{
|
|
if(e820.map[i].addr >= 0x100000UL && e820.map[i].addr < clip)
|
|
clip = e820.map[i].addr;
|
|
continue;
|
|
}
|
|
start = e820.map[i].addr;
|
|
end = e820.map[i].addr + e820.map[i].size;
|
|
if (start >= end)
|
|
continue;
|
|
if (end > top)
|
|
top = end;
|
|
}
|
|
/* Everything below 'top' should be RAM except for the ISA hole.
|
|
Because of the limited MCR's we want to map NV/ACPI into our
|
|
MCR range for gunk in RAM
|
|
|
|
Clip might cause us to MCR insufficient RAM but that is an
|
|
acceptable failure mode and should only bite obscure boxes with
|
|
a VESA hole at 15Mb
|
|
|
|
The second case Clip sometimes kicks in is when the EBDA is marked
|
|
as reserved. Again we fail safe with reasonable results
|
|
*/
|
|
|
|
if(top>clip)
|
|
top=clip;
|
|
|
|
return top;
|
|
}
|
|
|
|
/*
|
|
* Compute a set of MCR's to give maximum coverage
|
|
*/
|
|
|
|
static int __init centaur_mcr_compute(int nr, int key)
|
|
{
|
|
u32 mem = ramtop();
|
|
u32 root = power2(mem);
|
|
u32 base = root;
|
|
u32 top = root;
|
|
u32 floor = 0;
|
|
int ct = 0;
|
|
|
|
while(ct<nr)
|
|
{
|
|
u32 fspace = 0;
|
|
|
|
/*
|
|
* Find the largest block we will fill going upwards
|
|
*/
|
|
|
|
u32 high = power2(mem-top);
|
|
|
|
/*
|
|
* Find the largest block we will fill going downwards
|
|
*/
|
|
|
|
u32 low = base/2;
|
|
|
|
/*
|
|
* Don't fill below 1Mb going downwards as there
|
|
* is an ISA hole in the way.
|
|
*/
|
|
|
|
if(base <= 1024*1024)
|
|
low = 0;
|
|
|
|
/*
|
|
* See how much space we could cover by filling below
|
|
* the ISA hole
|
|
*/
|
|
|
|
if(floor == 0)
|
|
fspace = 512*1024;
|
|
else if(floor ==512*1024)
|
|
fspace = 128*1024;
|
|
|
|
/* And forget ROM space */
|
|
|
|
/*
|
|
* Now install the largest coverage we get
|
|
*/
|
|
|
|
if(fspace > high && fspace > low)
|
|
{
|
|
centaur_mcr_insert(ct, floor, fspace, key);
|
|
floor += fspace;
|
|
}
|
|
else if(high > low)
|
|
{
|
|
centaur_mcr_insert(ct, top, high, key);
|
|
top += high;
|
|
}
|
|
else if(low > 0)
|
|
{
|
|
base -= low;
|
|
centaur_mcr_insert(ct, base, low, key);
|
|
}
|
|
else break;
|
|
ct++;
|
|
}
|
|
/*
|
|
* We loaded ct values. We now need to set the mask. The caller
|
|
* must do this bit.
|
|
*/
|
|
|
|
return ct;
|
|
}
|
|
|
|
static void __init centaur_create_optimal_mcr(void)
|
|
{
|
|
int i;
|
|
/*
|
|
* Allocate up to 6 mcrs to mark as much of ram as possible
|
|
* as write combining and weak write ordered.
|
|
*
|
|
* To experiment with: Linux never uses stack operations for
|
|
* mmio spaces so we could globally enable stack operation wc
|
|
*
|
|
* Load the registers with type 31 - full write combining, all
|
|
* writes weakly ordered.
|
|
*/
|
|
int used = centaur_mcr_compute(6, 31);
|
|
|
|
/*
|
|
* Wipe unused MCRs
|
|
*/
|
|
|
|
for(i=used;i<8;i++)
|
|
wrmsr(MSR_IDT_MCR0+i, 0, 0);
|
|
}
|
|
|
|
static void __init winchip2_create_optimal_mcr(void)
|
|
{
|
|
u32 lo, hi;
|
|
int i;
|
|
|
|
/*
|
|
* Allocate up to 6 mcrs to mark as much of ram as possible
|
|
* as write combining, weak store ordered.
|
|
*
|
|
* Load the registers with type 25
|
|
* 8 - weak write ordering
|
|
* 16 - weak read ordering
|
|
* 1 - write combining
|
|
*/
|
|
|
|
int used = centaur_mcr_compute(6, 25);
|
|
|
|
/*
|
|
* Mark the registers we are using.
|
|
*/
|
|
|
|
rdmsr(MSR_IDT_MCR_CTRL, lo, hi);
|
|
for(i=0;i<used;i++)
|
|
lo|=1<<(9+i);
|
|
wrmsr(MSR_IDT_MCR_CTRL, lo, hi);
|
|
|
|
/*
|
|
* Wipe unused MCRs
|
|
*/
|
|
|
|
for(i=used;i<8;i++)
|
|
wrmsr(MSR_IDT_MCR0+i, 0, 0);
|
|
}
|
|
|
|
/*
|
|
* Handle the MCR key on the Winchip 2.
|
|
*/
|
|
|
|
static void __init winchip2_unprotect_mcr(void)
|
|
{
|
|
u32 lo, hi;
|
|
u32 key;
|
|
|
|
rdmsr(MSR_IDT_MCR_CTRL, lo, hi);
|
|
lo&=~0x1C0; /* blank bits 8-6 */
|
|
key = (lo>>17) & 7;
|
|
lo |= key<<6; /* replace with unlock key */
|
|
wrmsr(MSR_IDT_MCR_CTRL, lo, hi);
|
|
}
|
|
|
|
static void __init winchip2_protect_mcr(void)
|
|
{
|
|
u32 lo, hi;
|
|
|
|
rdmsr(MSR_IDT_MCR_CTRL, lo, hi);
|
|
lo&=~0x1C0; /* blank bits 8-6 */
|
|
wrmsr(MSR_IDT_MCR_CTRL, lo, hi);
|
|
}
|
|
#endif /* CONFIG_X86_OOSTORE */
|
|
|
|
#define ACE_PRESENT (1 << 6)
|
|
#define ACE_ENABLED (1 << 7)
|
|
#define ACE_FCR (1 << 28) /* MSR_VIA_FCR */
|
|
|
|
#define RNG_PRESENT (1 << 2)
|
|
#define RNG_ENABLED (1 << 3)
|
|
#define RNG_ENABLE (1 << 6) /* MSR_VIA_RNG */
|
|
|
|
static void __init init_c3(struct cpuinfo_x86 *c)
|
|
{
|
|
u32 lo, hi;
|
|
|
|
/* Test for Centaur Extended Feature Flags presence */
|
|
if (cpuid_eax(0xC0000000) >= 0xC0000001) {
|
|
u32 tmp = cpuid_edx(0xC0000001);
|
|
|
|
/* enable ACE unit, if present and disabled */
|
|
if ((tmp & (ACE_PRESENT | ACE_ENABLED)) == ACE_PRESENT) {
|
|
rdmsr (MSR_VIA_FCR, lo, hi);
|
|
lo |= ACE_FCR; /* enable ACE unit */
|
|
wrmsr (MSR_VIA_FCR, lo, hi);
|
|
printk(KERN_INFO "CPU: Enabled ACE h/w crypto\n");
|
|
}
|
|
|
|
/* enable RNG unit, if present and disabled */
|
|
if ((tmp & (RNG_PRESENT | RNG_ENABLED)) == RNG_PRESENT) {
|
|
rdmsr (MSR_VIA_RNG, lo, hi);
|
|
lo |= RNG_ENABLE; /* enable RNG unit */
|
|
wrmsr (MSR_VIA_RNG, lo, hi);
|
|
printk(KERN_INFO "CPU: Enabled h/w RNG\n");
|
|
}
|
|
|
|
/* store Centaur Extended Feature Flags as
|
|
* word 5 of the CPU capability bit array
|
|
*/
|
|
c->x86_capability[5] = cpuid_edx(0xC0000001);
|
|
}
|
|
|
|
/* Cyrix III family needs CX8 & PGE explicity enabled. */
|
|
if (c->x86_model >=6 && c->x86_model <= 9) {
|
|
rdmsr (MSR_VIA_FCR, lo, hi);
|
|
lo |= (1<<1 | 1<<7);
|
|
wrmsr (MSR_VIA_FCR, lo, hi);
|
|
set_bit(X86_FEATURE_CX8, c->x86_capability);
|
|
}
|
|
|
|
/* Before Nehemiah, the C3's had 3dNOW! */
|
|
if (c->x86_model >=6 && c->x86_model <9)
|
|
set_bit(X86_FEATURE_3DNOW, c->x86_capability);
|
|
|
|
get_model_name(c);
|
|
display_cacheinfo(c);
|
|
}
|
|
|
|
static void __init init_centaur(struct cpuinfo_x86 *c)
|
|
{
|
|
enum {
|
|
ECX8=1<<1,
|
|
EIERRINT=1<<2,
|
|
DPM=1<<3,
|
|
DMCE=1<<4,
|
|
DSTPCLK=1<<5,
|
|
ELINEAR=1<<6,
|
|
DSMC=1<<7,
|
|
DTLOCK=1<<8,
|
|
EDCTLB=1<<8,
|
|
EMMX=1<<9,
|
|
DPDC=1<<11,
|
|
EBRPRED=1<<12,
|
|
DIC=1<<13,
|
|
DDC=1<<14,
|
|
DNA=1<<15,
|
|
ERETSTK=1<<16,
|
|
E2MMX=1<<19,
|
|
EAMD3D=1<<20,
|
|
};
|
|
|
|
char *name;
|
|
u32 fcr_set=0;
|
|
u32 fcr_clr=0;
|
|
u32 lo,hi,newlo;
|
|
u32 aa,bb,cc,dd;
|
|
|
|
/* Bit 31 in normal CPUID used for nonstandard 3DNow ID;
|
|
3DNow is IDd by bit 31 in extended CPUID (1*32+31) anyway */
|
|
clear_bit(0*32+31, c->x86_capability);
|
|
|
|
switch (c->x86) {
|
|
|
|
case 5:
|
|
switch(c->x86_model) {
|
|
case 4:
|
|
name="C6";
|
|
fcr_set=ECX8|DSMC|EDCTLB|EMMX|ERETSTK;
|
|
fcr_clr=DPDC;
|
|
printk(KERN_NOTICE "Disabling bugged TSC.\n");
|
|
clear_bit(X86_FEATURE_TSC, c->x86_capability);
|
|
#ifdef CONFIG_X86_OOSTORE
|
|
centaur_create_optimal_mcr();
|
|
/* Enable
|
|
write combining on non-stack, non-string
|
|
write combining on string, all types
|
|
weak write ordering
|
|
|
|
The C6 original lacks weak read order
|
|
|
|
Note 0x120 is write only on Winchip 1 */
|
|
|
|
wrmsr(MSR_IDT_MCR_CTRL, 0x01F0001F, 0);
|
|
#endif
|
|
break;
|
|
case 8:
|
|
switch(c->x86_mask) {
|
|
default:
|
|
name="2";
|
|
break;
|
|
case 7 ... 9:
|
|
name="2A";
|
|
break;
|
|
case 10 ... 15:
|
|
name="2B";
|
|
break;
|
|
}
|
|
fcr_set=ECX8|DSMC|DTLOCK|EMMX|EBRPRED|ERETSTK|E2MMX|EAMD3D;
|
|
fcr_clr=DPDC;
|
|
#ifdef CONFIG_X86_OOSTORE
|
|
winchip2_unprotect_mcr();
|
|
winchip2_create_optimal_mcr();
|
|
rdmsr(MSR_IDT_MCR_CTRL, lo, hi);
|
|
/* Enable
|
|
write combining on non-stack, non-string
|
|
write combining on string, all types
|
|
weak write ordering
|
|
*/
|
|
lo|=31;
|
|
wrmsr(MSR_IDT_MCR_CTRL, lo, hi);
|
|
winchip2_protect_mcr();
|
|
#endif
|
|
break;
|
|
case 9:
|
|
name="3";
|
|
fcr_set=ECX8|DSMC|DTLOCK|EMMX|EBRPRED|ERETSTK|E2MMX|EAMD3D;
|
|
fcr_clr=DPDC;
|
|
#ifdef CONFIG_X86_OOSTORE
|
|
winchip2_unprotect_mcr();
|
|
winchip2_create_optimal_mcr();
|
|
rdmsr(MSR_IDT_MCR_CTRL, lo, hi);
|
|
/* Enable
|
|
write combining on non-stack, non-string
|
|
write combining on string, all types
|
|
weak write ordering
|
|
*/
|
|
lo|=31;
|
|
wrmsr(MSR_IDT_MCR_CTRL, lo, hi);
|
|
winchip2_protect_mcr();
|
|
#endif
|
|
break;
|
|
default:
|
|
name="??";
|
|
}
|
|
|
|
rdmsr(MSR_IDT_FCR1, lo, hi);
|
|
newlo=(lo|fcr_set) & (~fcr_clr);
|
|
|
|
if (newlo!=lo) {
|
|
printk(KERN_INFO "Centaur FCR was 0x%X now 0x%X\n", lo, newlo );
|
|
wrmsr(MSR_IDT_FCR1, newlo, hi );
|
|
} else {
|
|
printk(KERN_INFO "Centaur FCR is 0x%X\n",lo);
|
|
}
|
|
/* Emulate MTRRs using Centaur's MCR. */
|
|
set_bit(X86_FEATURE_CENTAUR_MCR, c->x86_capability);
|
|
/* Report CX8 */
|
|
set_bit(X86_FEATURE_CX8, c->x86_capability);
|
|
/* Set 3DNow! on Winchip 2 and above. */
|
|
if (c->x86_model >=8)
|
|
set_bit(X86_FEATURE_3DNOW, c->x86_capability);
|
|
/* See if we can find out some more. */
|
|
if ( cpuid_eax(0x80000000) >= 0x80000005 ) {
|
|
/* Yes, we can. */
|
|
cpuid(0x80000005,&aa,&bb,&cc,&dd);
|
|
/* Add L1 data and code cache sizes. */
|
|
c->x86_cache_size = (cc>>24)+(dd>>24);
|
|
}
|
|
sprintf( c->x86_model_id, "WinChip %s", name );
|
|
break;
|
|
|
|
case 6:
|
|
init_c3(c);
|
|
break;
|
|
}
|
|
}
|
|
|
|
static unsigned int centaur_size_cache(struct cpuinfo_x86 * c, unsigned int size)
|
|
{
|
|
/* VIA C3 CPUs (670-68F) need further shifting. */
|
|
if ((c->x86 == 6) && ((c->x86_model == 7) || (c->x86_model == 8)))
|
|
size >>= 8;
|
|
|
|
/* VIA also screwed up Nehemiah stepping 1, and made
|
|
it return '65KB' instead of '64KB'
|
|
- Note, it seems this may only be in engineering samples. */
|
|
if ((c->x86==6) && (c->x86_model==9) && (c->x86_mask==1) && (size==65))
|
|
size -=1;
|
|
|
|
return size;
|
|
}
|
|
|
|
static struct cpu_dev centaur_cpu_dev __initdata = {
|
|
.c_vendor = "Centaur",
|
|
.c_ident = { "CentaurHauls" },
|
|
.c_init = init_centaur,
|
|
.c_size_cache = centaur_size_cache,
|
|
};
|
|
|
|
int __init centaur_init_cpu(void)
|
|
{
|
|
cpu_devs[X86_VENDOR_CENTAUR] = ¢aur_cpu_dev;
|
|
return 0;
|
|
}
|
|
|
|
//early_arch_initcall(centaur_init_cpu);
|