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-rw-r--r--src/arch/x86/cpu.c273
1 files changed, 273 insertions, 0 deletions
diff --git a/src/arch/x86/cpu.c b/src/arch/x86/cpu.c
new file mode 100644
index 0000000000..3eb7b9439e
--- /dev/null
+++ b/src/arch/x86/cpu.c
@@ -0,0 +1,273 @@
+#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>
+
+#ifndef __x86_64__
+/* 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;
+}
+
+/*
+ * 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;
+}
+#endif
+
+/* 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 */
+
+#ifndef __x86_64__
+ /* Find the id and vendor_name */
+ if (!cpu_have_cpuid()) {
+ /* 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);
+ }
+ }
+#endif
+ if (cpu_have_cpuid()) {
+ 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;
+ }
+ }
+}
+
+struct cpu_driver *find_cpu_driver(struct device *cpu)
+{
+ struct cpu_driver *driver;
+ 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))
+ {
+ return driver;
+ }
+ if (X86_VENDOR_ANY == id->vendor)
+ return driver;
+ }
+ }
+ return NULL;
+}
+
+static void set_cpu_ops(struct device *cpu)
+{
+ struct cpu_driver *driver = find_cpu_driver(cpu);
+ cpu->ops = driver ? driver->ops : NULL;
+}
+
+void cpu_initialize(unsigned int index)
+{
+ /* 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(BIOS_INFO, "Initializing CPU #%d\n", index);
+
+ cpu = info->cpu;
+ if (!cpu) {
+ die("CPU: missing cpu device structure");
+ }
+
+ post_log_path(cpu);
+
+ /* Find what type of cpu we are dealing with */
+ identify_cpu(cpu);
+ printk(BIOS_DEBUG, "CPU: vendor %s device %x\n",
+ cpu_vendor_name(cpu->vendor), cpu->device);
+
+ get_fms(&c, cpu->device);
+
+ printk(BIOS_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(BIOS_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);
+ }
+ post_log_clear();
+
+ printk(BIOS_INFO, "CPU #%d initialized\n", index);
+
+ return;
+}
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