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#include <console/console.h>
#include <cpu/cpu.h>
#include <arch/io.h>
#include <string.h>
#include <cpu/x86/mtrr.h>
#include <cpu/x86/msr.h>
#include <cpu/x86/lapic.h>
#include <arch/cpu.h>
#include <device/path.h>
#include <device/device.h>
#include <smp/spinlock.h>
/* Standard macro to see if a specific flag is changeable */
static inline int flag_is_changeable_p(uint32_t flag)
{
uint32_t f1, f2;
asm(
"pushfl\n\t"
"pushfl\n\t"
"popl %0\n\t"
"movl %0,%1\n\t"
"xorl %2,%0\n\t"
"pushl %0\n\t"
"popfl\n\t"
"pushfl\n\t"
"popl %0\n\t"
"popfl\n\t"
: "=&r" (f1), "=&r" (f2)
: "ir" (flag));
return ((f1^f2) & flag) != 0;
}
/* Probe for the CPUID instruction */
static int have_cpuid_p(void)
{
return flag_is_changeable_p(X86_EFLAGS_ID);
}
/*
* Cyrix CPUs without cpuid or with cpuid not yet enabled can be detected
* by the fact that they preserve the flags across the division of 5/2.
* PII and PPro exhibit this behavior too, but they have cpuid available.
*/
/*
* Perform the Cyrix 5/2 test. A Cyrix won't change
* the flags, while other 486 chips will.
*/
static inline int test_cyrix_52div(void)
{
unsigned int test;
__asm__ __volatile__(
"sahf\n\t" /* clear flags (%eax = 0x0005) */
"div %b2\n\t" /* divide 5 by 2 */
"lahf" /* store flags into %ah */
: "=a" (test)
: "0" (5), "q" (2)
: "cc");
/* AH is 0x02 on Cyrix after the divide.. */
return (unsigned char) (test >> 8) == 0x02;
}
/*
* Detect a NexGen CPU running without BIOS hypercode new enough
* to have CPUID. (Thanks to Herbert Oppmann)
*/
static int deep_magic_nexgen_probe(void)
{
int ret;
__asm__ __volatile__ (
" movw $0x5555, %%ax\n"
" xorw %%dx,%%dx\n"
" movw $2, %%cx\n"
" divw %%cx\n"
" movl $0, %%eax\n"
" jnz 1f\n"
" movl $1, %%eax\n"
"1:\n"
: "=a" (ret) : : "cx", "dx" );
return ret;
}
/* List of cpu vendor strings along with their normalized
* id values.
*/
static struct {
int vendor;
const char *name;
} x86_vendors[] = {
{ X86_VENDOR_INTEL, "GenuineIntel", },
{ X86_VENDOR_CYRIX, "CyrixInstead", },
{ X86_VENDOR_AMD, "AuthenticAMD", },
{ X86_VENDOR_UMC, "UMC UMC UMC ", },
{ X86_VENDOR_NEXGEN, "NexGenDriven", },
{ X86_VENDOR_CENTAUR, "CentaurHauls", },
{ X86_VENDOR_RISE, "RiseRiseRise", },
{ X86_VENDOR_TRANSMETA, "GenuineTMx86", },
{ X86_VENDOR_TRANSMETA, "TransmetaCPU", },
{ X86_VENDOR_NSC, "Geode by NSC", },
{ X86_VENDOR_SIS, "SiS SiS SiS ", },
};
static const char *x86_vendor_name[] = {
[X86_VENDOR_INTEL] = "Intel",
[X86_VENDOR_CYRIX] = "Cyrix",
[X86_VENDOR_AMD] = "AMD",
[X86_VENDOR_UMC] = "UMC",
[X86_VENDOR_NEXGEN] = "NexGen",
[X86_VENDOR_CENTAUR] = "Centaur",
[X86_VENDOR_RISE] = "Rise",
[X86_VENDOR_TRANSMETA] = "Transmeta",
[X86_VENDOR_NSC] = "NSC",
[X86_VENDOR_SIS] = "SiS",
};
static const char *cpu_vendor_name(int vendor)
{
const char *name;
name = "<invalid cpu vendor>";
if ((vendor < (ARRAY_SIZE(x86_vendor_name))) &&
(x86_vendor_name[vendor] != 0))
{
name = x86_vendor_name[vendor];
}
return name;
}
static void identify_cpu(struct device *cpu)
{
char vendor_name[16];
int i;
vendor_name[0] = '\0'; /* Unset */
/* Find the id and vendor_name */
if (!have_cpuid_p()) {
/* Its a 486 if we can modify the AC flag */
if (flag_is_changeable_p(X86_EFLAGS_AC)) {
cpu->device = 0x00000400; /* 486 */
} else {
cpu->device = 0x00000300; /* 386 */
}
if ((cpu->device == 0x00000400) && test_cyrix_52div()) {
memcpy(vendor_name, "CyrixInstead", 13);
/* If we ever care we can enable cpuid here */
}
/* Detect NexGen with old hypercode */
else if (deep_magic_nexgen_probe()) {
memcpy(vendor_name, "NexGenDriven", 13);
}
}
if (have_cpuid_p()) {
int cpuid_level;
struct cpuid_result result;
result = cpuid(0x00000000);
cpuid_level = result.eax;
vendor_name[ 0] = (result.ebx >> 0) & 0xff;
vendor_name[ 1] = (result.ebx >> 8) & 0xff;
vendor_name[ 2] = (result.ebx >> 16) & 0xff;
vendor_name[ 3] = (result.ebx >> 24) & 0xff;
vendor_name[ 4] = (result.edx >> 0) & 0xff;
vendor_name[ 5] = (result.edx >> 8) & 0xff;
vendor_name[ 6] = (result.edx >> 16) & 0xff;
vendor_name[ 7] = (result.edx >> 24) & 0xff;
vendor_name[ 8] = (result.ecx >> 0) & 0xff;
vendor_name[ 9] = (result.ecx >> 8) & 0xff;
vendor_name[10] = (result.ecx >> 16) & 0xff;
vendor_name[11] = (result.ecx >> 24) & 0xff;
vendor_name[12] = '\0';
/* Intel-defined flags: level 0x00000001 */
if (cpuid_level >= 0x00000001) {
cpu->device = cpuid_eax(0x00000001);
}
else {
/* Have CPUID level 0 only unheard of */
cpu->device = 0x00000400;
}
}
cpu->vendor = X86_VENDOR_UNKNOWN;
for(i = 0; i < ARRAY_SIZE(x86_vendors); i++) {
if (memcmp(vendor_name, x86_vendors[i].name, 12) == 0) {
cpu->vendor = x86_vendors[i].vendor;
break;
}
}
}
static void set_cpu_ops(struct device *cpu)
{
struct cpu_driver *driver;
cpu->ops = 0;
for (driver = cpu_drivers; driver < ecpu_drivers; driver++) {
struct cpu_device_id *id;
for(id = driver->id_table; id->vendor != X86_VENDOR_INVALID; id++) {
if ((cpu->vendor == id->vendor) &&
(cpu->device == id->device))
{
goto found;
}
}
}
return;
found:
cpu->ops = driver->ops;
}
void cpu_initialize(void)
{
/* Because we busy wait at the printk spinlock.
* It is important to keep the number of printed messages
* from secondary cpus to a minimum, when debugging is
* disabled.
*/
struct device *cpu;
struct cpu_info *info;
struct cpuinfo_x86 c;
info = cpu_info();
printk_info("Initializing CPU #%ld\n", info->index);
cpu = info->cpu;
if (!cpu) {
die("CPU: missing cpu device structure");
}
/* Find what type of cpu we are dealing with */
identify_cpu(cpu);
printk_debug("CPU: vendor %s device %x\n",
cpu_vendor_name(cpu->vendor), cpu->device);
get_fms(&c, cpu->device);
printk_debug("CPU: family %02x, model %02x, stepping %02x\n", c.x86, c.x86_model, c.x86_mask);
/* Lookup the cpu's operations */
set_cpu_ops(cpu);
if(!cpu->ops) {
/* mask out the stepping and try again */
cpu->device -= c.x86_mask;
set_cpu_ops(cpu);
cpu->device += c.x86_mask;
if(!cpu->ops) die("Unknown cpu");
printk_debug("Using generic cpu ops (good)\n");
}
/* Initialize the cpu */
if (cpu->ops && cpu->ops->init) {
cpu->enabled = 1;
cpu->initialized = 1;
cpu->ops->init(cpu);
}
printk_info("CPU #%ld initialized\n", info->index);
return;
}
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