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Diffstat (limited to 'arch/x86/kernel/cpu/common_64.c')
-rw-r--r--arch/x86/kernel/cpu/common_64.c681
1 files changed, 681 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/common_64.c b/arch/x86/kernel/cpu/common_64.c
new file mode 100644
index 000000000000..7b8cc72feb40
--- /dev/null
+++ b/arch/x86/kernel/cpu/common_64.c
@@ -0,0 +1,681 @@
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/string.h>
+#include <linux/bootmem.h>
+#include <linux/bitops.h>
+#include <linux/module.h>
+#include <linux/kgdb.h>
+#include <linux/topology.h>
+#include <linux/string.h>
+#include <linux/delay.h>
+#include <linux/smp.h>
+#include <linux/module.h>
+#include <linux/percpu.h>
+#include <asm/processor.h>
+#include <asm/i387.h>
+#include <asm/msr.h>
+#include <asm/io.h>
+#include <asm/mmu_context.h>
+#include <asm/mtrr.h>
+#include <asm/mce.h>
+#include <asm/pat.h>
+#include <asm/numa.h>
+#ifdef CONFIG_X86_LOCAL_APIC
+#include <asm/mpspec.h>
+#include <asm/apic.h>
+#include <mach_apic.h>
+#endif
+#include <asm/pda.h>
+#include <asm/pgtable.h>
+#include <asm/processor.h>
+#include <asm/desc.h>
+#include <asm/atomic.h>
+#include <asm/proto.h>
+#include <asm/sections.h>
+#include <asm/setup.h>
+#include <asm/genapic.h>
+
+#include "cpu.h"
+
+/* We need valid kernel segments for data and code in long mode too
+ * IRET will check the segment types kkeil 2000/10/28
+ * Also sysret mandates a special GDT layout
+ */
+/* The TLS descriptors are currently at a different place compared to i386.
+ Hopefully nobody expects them at a fixed place (Wine?) */
+DEFINE_PER_CPU(struct gdt_page, gdt_page) = { .gdt = {
+ [GDT_ENTRY_KERNEL32_CS] = { { { 0x0000ffff, 0x00cf9b00 } } },
+ [GDT_ENTRY_KERNEL_CS] = { { { 0x0000ffff, 0x00af9b00 } } },
+ [GDT_ENTRY_KERNEL_DS] = { { { 0x0000ffff, 0x00cf9300 } } },
+ [GDT_ENTRY_DEFAULT_USER32_CS] = { { { 0x0000ffff, 0x00cffb00 } } },
+ [GDT_ENTRY_DEFAULT_USER_DS] = { { { 0x0000ffff, 0x00cff300 } } },
+ [GDT_ENTRY_DEFAULT_USER_CS] = { { { 0x0000ffff, 0x00affb00 } } },
+} };
+EXPORT_PER_CPU_SYMBOL_GPL(gdt_page);
+
+__u32 cleared_cpu_caps[NCAPINTS] __cpuinitdata;
+
+/* Current gdt points %fs at the "master" per-cpu area: after this,
+ * it's on the real one. */
+void switch_to_new_gdt(void)
+{
+ struct desc_ptr gdt_descr;
+
+ gdt_descr.address = (long)get_cpu_gdt_table(smp_processor_id());
+ gdt_descr.size = GDT_SIZE - 1;
+ load_gdt(&gdt_descr);
+}
+
+struct cpu_dev *cpu_devs[X86_VENDOR_NUM] = {};
+
+static void __cpuinit default_init(struct cpuinfo_x86 *c)
+{
+ display_cacheinfo(c);
+}
+
+static struct cpu_dev __cpuinitdata default_cpu = {
+ .c_init = default_init,
+ .c_vendor = "Unknown",
+};
+static struct cpu_dev *this_cpu __cpuinitdata = &default_cpu;
+
+int __cpuinit get_model_name(struct cpuinfo_x86 *c)
+{
+ unsigned int *v;
+
+ if (c->extended_cpuid_level < 0x80000004)
+ return 0;
+
+ v = (unsigned int *) c->x86_model_id;
+ cpuid(0x80000002, &v[0], &v[1], &v[2], &v[3]);
+ cpuid(0x80000003, &v[4], &v[5], &v[6], &v[7]);
+ cpuid(0x80000004, &v[8], &v[9], &v[10], &v[11]);
+ c->x86_model_id[48] = 0;
+ return 1;
+}
+
+
+void __cpuinit display_cacheinfo(struct cpuinfo_x86 *c)
+{
+ unsigned int n, dummy, ebx, ecx, edx;
+
+ n = c->extended_cpuid_level;
+
+ if (n >= 0x80000005) {
+ cpuid(0x80000005, &dummy, &ebx, &ecx, &edx);
+ printk(KERN_INFO "CPU: L1 I Cache: %dK (%d bytes/line), "
+ "D cache %dK (%d bytes/line)\n",
+ edx>>24, edx&0xFF, ecx>>24, ecx&0xFF);
+ c->x86_cache_size = (ecx>>24) + (edx>>24);
+ /* On K8 L1 TLB is inclusive, so don't count it */
+ c->x86_tlbsize = 0;
+ }
+
+ if (n >= 0x80000006) {
+ cpuid(0x80000006, &dummy, &ebx, &ecx, &edx);
+ ecx = cpuid_ecx(0x80000006);
+ c->x86_cache_size = ecx >> 16;
+ c->x86_tlbsize += ((ebx >> 16) & 0xfff) + (ebx & 0xfff);
+
+ printk(KERN_INFO "CPU: L2 Cache: %dK (%d bytes/line)\n",
+ c->x86_cache_size, ecx & 0xFF);
+ }
+}
+
+void __cpuinit detect_ht(struct cpuinfo_x86 *c)
+{
+#ifdef CONFIG_SMP
+ u32 eax, ebx, ecx, edx;
+ int index_msb, core_bits;
+
+ cpuid(1, &eax, &ebx, &ecx, &edx);
+
+
+ if (!cpu_has(c, X86_FEATURE_HT))
+ return;
+ if (cpu_has(c, X86_FEATURE_CMP_LEGACY))
+ goto out;
+
+ smp_num_siblings = (ebx & 0xff0000) >> 16;
+
+ if (smp_num_siblings == 1) {
+ printk(KERN_INFO "CPU: Hyper-Threading is disabled\n");
+ } else if (smp_num_siblings > 1) {
+
+ if (smp_num_siblings > NR_CPUS) {
+ printk(KERN_WARNING "CPU: Unsupported number of "
+ "siblings %d", smp_num_siblings);
+ smp_num_siblings = 1;
+ return;
+ }
+
+ index_msb = get_count_order(smp_num_siblings);
+ c->phys_proc_id = phys_pkg_id(index_msb);
+
+ smp_num_siblings = smp_num_siblings / c->x86_max_cores;
+
+ index_msb = get_count_order(smp_num_siblings);
+
+ core_bits = get_count_order(c->x86_max_cores);
+
+ c->cpu_core_id = phys_pkg_id(index_msb) &
+ ((1 << core_bits) - 1);
+ }
+out:
+ if ((c->x86_max_cores * smp_num_siblings) > 1) {
+ printk(KERN_INFO "CPU: Physical Processor ID: %d\n",
+ c->phys_proc_id);
+ printk(KERN_INFO "CPU: Processor Core ID: %d\n",
+ c->cpu_core_id);
+ }
+
+#endif
+}
+
+static void __cpuinit get_cpu_vendor(struct cpuinfo_x86 *c)
+{
+ char *v = c->x86_vendor_id;
+ int i;
+ static int printed;
+
+ for (i = 0; i < X86_VENDOR_NUM; i++) {
+ if (cpu_devs[i]) {
+ if (!strcmp(v, cpu_devs[i]->c_ident[0]) ||
+ (cpu_devs[i]->c_ident[1] &&
+ !strcmp(v, cpu_devs[i]->c_ident[1]))) {
+ c->x86_vendor = i;
+ this_cpu = cpu_devs[i];
+ return;
+ }
+ }
+ }
+ if (!printed) {
+ printed++;
+ printk(KERN_ERR "CPU: Vendor unknown, using generic init.\n");
+ printk(KERN_ERR "CPU: Your system may be unstable.\n");
+ }
+ c->x86_vendor = X86_VENDOR_UNKNOWN;
+}
+
+static void __init early_cpu_support_print(void)
+{
+ int i,j;
+ struct cpu_dev *cpu_devx;
+
+ printk("KERNEL supported cpus:\n");
+ for (i = 0; i < X86_VENDOR_NUM; i++) {
+ cpu_devx = cpu_devs[i];
+ if (!cpu_devx)
+ continue;
+ for (j = 0; j < 2; j++) {
+ if (!cpu_devx->c_ident[j])
+ continue;
+ printk(" %s %s\n", cpu_devx->c_vendor,
+ cpu_devx->c_ident[j]);
+ }
+ }
+}
+
+static void __cpuinit early_identify_cpu(struct cpuinfo_x86 *c);
+
+void __init early_cpu_init(void)
+{
+ struct cpu_vendor_dev *cvdev;
+
+ for (cvdev = __x86cpuvendor_start ;
+ cvdev < __x86cpuvendor_end ;
+ cvdev++)
+ cpu_devs[cvdev->vendor] = cvdev->cpu_dev;
+ early_cpu_support_print();
+ early_identify_cpu(&boot_cpu_data);
+}
+
+/* Do some early cpuid on the boot CPU to get some parameter that are
+ needed before check_bugs. Everything advanced is in identify_cpu
+ below. */
+static void __cpuinit early_identify_cpu(struct cpuinfo_x86 *c)
+{
+ u32 tfms, xlvl;
+
+ c->loops_per_jiffy = loops_per_jiffy;
+ c->x86_cache_size = -1;
+ c->x86_vendor = X86_VENDOR_UNKNOWN;
+ c->x86_model = c->x86_mask = 0; /* So far unknown... */
+ c->x86_vendor_id[0] = '\0'; /* Unset */
+ c->x86_model_id[0] = '\0'; /* Unset */
+ c->x86_clflush_size = 64;
+ c->x86_cache_alignment = c->x86_clflush_size;
+ c->x86_max_cores = 1;
+ c->x86_coreid_bits = 0;
+ c->extended_cpuid_level = 0;
+ memset(&c->x86_capability, 0, sizeof c->x86_capability);
+
+ /* Get vendor name */
+ cpuid(0x00000000, (unsigned int *)&c->cpuid_level,
+ (unsigned int *)&c->x86_vendor_id[0],
+ (unsigned int *)&c->x86_vendor_id[8],
+ (unsigned int *)&c->x86_vendor_id[4]);
+
+ get_cpu_vendor(c);
+
+ /* Initialize the standard set of capabilities */
+ /* Note that the vendor-specific code below might override */
+
+ /* Intel-defined flags: level 0x00000001 */
+ if (c->cpuid_level >= 0x00000001) {
+ __u32 misc;
+ cpuid(0x00000001, &tfms, &misc, &c->x86_capability[4],
+ &c->x86_capability[0]);
+ c->x86 = (tfms >> 8) & 0xf;
+ c->x86_model = (tfms >> 4) & 0xf;
+ c->x86_mask = tfms & 0xf;
+ if (c->x86 == 0xf)
+ c->x86 += (tfms >> 20) & 0xff;
+ if (c->x86 >= 0x6)
+ c->x86_model += ((tfms >> 16) & 0xF) << 4;
+ if (test_cpu_cap(c, X86_FEATURE_CLFLSH))
+ c->x86_clflush_size = ((misc >> 8) & 0xff) * 8;
+ } else {
+ /* Have CPUID level 0 only - unheard of */
+ c->x86 = 4;
+ }
+
+ c->initial_apicid = (cpuid_ebx(1) >> 24) & 0xff;
+#ifdef CONFIG_SMP
+ c->phys_proc_id = c->initial_apicid;
+#endif
+ /* AMD-defined flags: level 0x80000001 */
+ xlvl = cpuid_eax(0x80000000);
+ c->extended_cpuid_level = xlvl;
+ if ((xlvl & 0xffff0000) == 0x80000000) {
+ if (xlvl >= 0x80000001) {
+ c->x86_capability[1] = cpuid_edx(0x80000001);
+ c->x86_capability[6] = cpuid_ecx(0x80000001);
+ }
+ if (xlvl >= 0x80000004)
+ get_model_name(c); /* Default name */
+ }
+
+ /* Transmeta-defined flags: level 0x80860001 */
+ xlvl = cpuid_eax(0x80860000);
+ if ((xlvl & 0xffff0000) == 0x80860000) {
+ /* Don't set x86_cpuid_level here for now to not confuse. */
+ if (xlvl >= 0x80860001)
+ c->x86_capability[2] = cpuid_edx(0x80860001);
+ }
+
+ c->extended_cpuid_level = cpuid_eax(0x80000000);
+ if (c->extended_cpuid_level >= 0x80000007)
+ c->x86_power = cpuid_edx(0x80000007);
+
+ if (c->extended_cpuid_level >= 0x80000008) {
+ u32 eax = cpuid_eax(0x80000008);
+
+ c->x86_virt_bits = (eax >> 8) & 0xff;
+ c->x86_phys_bits = eax & 0xff;
+ }
+
+ /* Assume all 64-bit CPUs support 32-bit syscall */
+ set_cpu_cap(c, X86_FEATURE_SYSCALL32);
+
+ if (c->x86_vendor != X86_VENDOR_UNKNOWN &&
+ cpu_devs[c->x86_vendor]->c_early_init)
+ cpu_devs[c->x86_vendor]->c_early_init(c);
+
+ validate_pat_support(c);
+
+ /* early_param could clear that, but recall get it set again */
+ if (disable_apic)
+ clear_cpu_cap(c, X86_FEATURE_APIC);
+}
+
+/*
+ * This does the hard work of actually picking apart the CPU stuff...
+ */
+static void __cpuinit identify_cpu(struct cpuinfo_x86 *c)
+{
+ int i;
+
+ early_identify_cpu(c);
+
+ init_scattered_cpuid_features(c);
+
+ c->apicid = phys_pkg_id(0);
+
+ /*
+ * Vendor-specific initialization. In this section we
+ * canonicalize the feature flags, meaning if there are
+ * features a certain CPU supports which CPUID doesn't
+ * tell us, CPUID claiming incorrect flags, or other bugs,
+ * we handle them here.
+ *
+ * At the end of this section, c->x86_capability better
+ * indicate the features this CPU genuinely supports!
+ */
+ if (this_cpu->c_init)
+ this_cpu->c_init(c);
+
+ detect_ht(c);
+
+ /*
+ * On SMP, boot_cpu_data holds the common feature set between
+ * all CPUs; so make sure that we indicate which features are
+ * common between the CPUs. The first time this routine gets
+ * executed, c == &boot_cpu_data.
+ */
+ if (c != &boot_cpu_data) {
+ /* AND the already accumulated flags with these */
+ for (i = 0; i < NCAPINTS; i++)
+ boot_cpu_data.x86_capability[i] &= c->x86_capability[i];
+ }
+
+ /* Clear all flags overriden by options */
+ for (i = 0; i < NCAPINTS; i++)
+ c->x86_capability[i] &= ~cleared_cpu_caps[i];
+
+#ifdef CONFIG_X86_MCE
+ mcheck_init(c);
+#endif
+ select_idle_routine(c);
+
+#ifdef CONFIG_NUMA
+ numa_add_cpu(smp_processor_id());
+#endif
+
+}
+
+void __cpuinit identify_boot_cpu(void)
+{
+ identify_cpu(&boot_cpu_data);
+}
+
+void __cpuinit identify_secondary_cpu(struct cpuinfo_x86 *c)
+{
+ BUG_ON(c == &boot_cpu_data);
+ identify_cpu(c);
+ mtrr_ap_init();
+}
+
+static __init int setup_noclflush(char *arg)
+{
+ setup_clear_cpu_cap(X86_FEATURE_CLFLSH);
+ return 1;
+}
+__setup("noclflush", setup_noclflush);
+
+void __cpuinit print_cpu_info(struct cpuinfo_x86 *c)
+{
+ if (c->x86_model_id[0])
+ printk(KERN_CONT "%s", c->x86_model_id);
+
+ if (c->x86_mask || c->cpuid_level >= 0)
+ printk(KERN_CONT " stepping %02x\n", c->x86_mask);
+ else
+ printk(KERN_CONT "\n");
+}
+
+static __init int setup_disablecpuid(char *arg)
+{
+ int bit;
+ if (get_option(&arg, &bit) && bit < NCAPINTS*32)
+ setup_clear_cpu_cap(bit);
+ else
+ return 0;
+ return 1;
+}
+__setup("clearcpuid=", setup_disablecpuid);
+
+cpumask_t cpu_initialized __cpuinitdata = CPU_MASK_NONE;
+
+struct x8664_pda **_cpu_pda __read_mostly;
+EXPORT_SYMBOL(_cpu_pda);
+
+struct desc_ptr idt_descr = { 256 * 16 - 1, (unsigned long) idt_table };
+
+char boot_cpu_stack[IRQSTACKSIZE] __page_aligned_bss;
+
+unsigned long __supported_pte_mask __read_mostly = ~0UL;
+EXPORT_SYMBOL_GPL(__supported_pte_mask);
+
+static int do_not_nx __cpuinitdata;
+
+/* noexec=on|off
+Control non executable mappings for 64bit processes.
+
+on Enable(default)
+off Disable
+*/
+static int __init nonx_setup(char *str)
+{
+ if (!str)
+ return -EINVAL;
+ if (!strncmp(str, "on", 2)) {
+ __supported_pte_mask |= _PAGE_NX;
+ do_not_nx = 0;
+ } else if (!strncmp(str, "off", 3)) {
+ do_not_nx = 1;
+ __supported_pte_mask &= ~_PAGE_NX;
+ }
+ return 0;
+}
+early_param("noexec", nonx_setup);
+
+int force_personality32;
+
+/* noexec32=on|off
+Control non executable heap for 32bit processes.
+To control the stack too use noexec=off
+
+on PROT_READ does not imply PROT_EXEC for 32bit processes (default)
+off PROT_READ implies PROT_EXEC
+*/
+static int __init nonx32_setup(char *str)
+{
+ if (!strcmp(str, "on"))
+ force_personality32 &= ~READ_IMPLIES_EXEC;
+ else if (!strcmp(str, "off"))
+ force_personality32 |= READ_IMPLIES_EXEC;
+ return 1;
+}
+__setup("noexec32=", nonx32_setup);
+
+void pda_init(int cpu)
+{
+ struct x8664_pda *pda = cpu_pda(cpu);
+
+ /* Setup up data that may be needed in __get_free_pages early */
+ loadsegment(fs, 0);
+ loadsegment(gs, 0);
+ /* Memory clobbers used to order PDA accessed */
+ mb();
+ wrmsrl(MSR_GS_BASE, pda);
+ mb();
+
+ pda->cpunumber = cpu;
+ pda->irqcount = -1;
+ pda->kernelstack = (unsigned long)stack_thread_info() -
+ PDA_STACKOFFSET + THREAD_SIZE;
+ pda->active_mm = &init_mm;
+ pda->mmu_state = 0;
+
+ if (cpu == 0) {
+ /* others are initialized in smpboot.c */
+ pda->pcurrent = &init_task;
+ pda->irqstackptr = boot_cpu_stack;
+ } else {
+ pda->irqstackptr = (char *)
+ __get_free_pages(GFP_ATOMIC, IRQSTACK_ORDER);
+ if (!pda->irqstackptr)
+ panic("cannot allocate irqstack for cpu %d", cpu);
+
+ if (pda->nodenumber == 0 && cpu_to_node(cpu) != NUMA_NO_NODE)
+ pda->nodenumber = cpu_to_node(cpu);
+ }
+
+ pda->irqstackptr += IRQSTACKSIZE-64;
+}
+
+char boot_exception_stacks[(N_EXCEPTION_STACKS - 1) * EXCEPTION_STKSZ +
+ DEBUG_STKSZ]
+__attribute__((section(".bss.page_aligned")));
+
+extern asmlinkage void ignore_sysret(void);
+
+/* May not be marked __init: used by software suspend */
+void syscall_init(void)
+{
+ /*
+ * LSTAR and STAR live in a bit strange symbiosis.
+ * They both write to the same internal register. STAR allows to
+ * set CS/DS but only a 32bit target. LSTAR sets the 64bit rip.
+ */
+ wrmsrl(MSR_STAR, ((u64)__USER32_CS)<<48 | ((u64)__KERNEL_CS)<<32);
+ wrmsrl(MSR_LSTAR, system_call);
+ wrmsrl(MSR_CSTAR, ignore_sysret);
+
+#ifdef CONFIG_IA32_EMULATION
+ syscall32_cpu_init();
+#endif
+
+ /* Flags to clear on syscall */
+ wrmsrl(MSR_SYSCALL_MASK,
+ X86_EFLAGS_TF|X86_EFLAGS_DF|X86_EFLAGS_IF|X86_EFLAGS_IOPL);
+}
+
+void __cpuinit check_efer(void)
+{
+ unsigned long efer;
+
+ rdmsrl(MSR_EFER, efer);
+ if (!(efer & EFER_NX) || do_not_nx)
+ __supported_pte_mask &= ~_PAGE_NX;
+}
+
+unsigned long kernel_eflags;
+
+/*
+ * Copies of the original ist values from the tss are only accessed during
+ * debugging, no special alignment required.
+ */
+DEFINE_PER_CPU(struct orig_ist, orig_ist);
+
+/*
+ * cpu_init() initializes state that is per-CPU. Some data is already
+ * initialized (naturally) in the bootstrap process, such as the GDT
+ * and IDT. We reload them nevertheless, this function acts as a
+ * 'CPU state barrier', nothing should get across.
+ * A lot of state is already set up in PDA init.
+ */
+void __cpuinit cpu_init(void)
+{
+ int cpu = stack_smp_processor_id();
+ struct tss_struct *t = &per_cpu(init_tss, cpu);
+ struct orig_ist *orig_ist = &per_cpu(orig_ist, cpu);
+ unsigned long v;
+ char *estacks = NULL;
+ struct task_struct *me;
+ int i;
+
+ /* CPU 0 is initialised in head64.c */
+ if (cpu != 0)
+ pda_init(cpu);
+ else
+ estacks = boot_exception_stacks;
+
+ me = current;
+
+ if (cpu_test_and_set(cpu, cpu_initialized))
+ panic("CPU#%d already initialized!\n", cpu);
+
+ printk(KERN_INFO "Initializing CPU#%d\n", cpu);
+
+ clear_in_cr4(X86_CR4_VME|X86_CR4_PVI|X86_CR4_TSD|X86_CR4_DE);
+
+ /*
+ * Initialize the per-CPU GDT with the boot GDT,
+ * and set up the GDT descriptor:
+ */
+
+ switch_to_new_gdt();
+ load_idt((const struct desc_ptr *)&idt_descr);
+
+ memset(me->thread.tls_array, 0, GDT_ENTRY_TLS_ENTRIES * 8);
+ syscall_init();
+
+ wrmsrl(MSR_FS_BASE, 0);
+ wrmsrl(MSR_KERNEL_GS_BASE, 0);
+ barrier();
+
+ check_efer();
+
+ /*
+ * set up and load the per-CPU TSS
+ */
+ for (v = 0; v < N_EXCEPTION_STACKS; v++) {
+ static const unsigned int order[N_EXCEPTION_STACKS] = {
+ [0 ... N_EXCEPTION_STACKS - 1] = EXCEPTION_STACK_ORDER,
+ [DEBUG_STACK - 1] = DEBUG_STACK_ORDER
+ };
+ if (cpu) {
+ estacks = (char *)__get_free_pages(GFP_ATOMIC, order[v]);
+ if (!estacks)
+ panic("Cannot allocate exception stack %ld %d\n",
+ v, cpu);
+ }
+ estacks += PAGE_SIZE << order[v];
+ orig_ist->ist[v] = t->x86_tss.ist[v] = (unsigned long)estacks;
+ }
+
+ t->x86_tss.io_bitmap_base = offsetof(struct tss_struct, io_bitmap);
+ /*
+ * <= is required because the CPU will access up to
+ * 8 bits beyond the end of the IO permission bitmap.
+ */
+ for (i = 0; i <= IO_BITMAP_LONGS; i++)
+ t->io_bitmap[i] = ~0UL;
+
+ atomic_inc(&init_mm.mm_count);
+ me->active_mm = &init_mm;
+ if (me->mm)
+ BUG();
+ enter_lazy_tlb(&init_mm, me);
+
+ load_sp0(t, &current->thread);
+ set_tss_desc(cpu, t);
+ load_TR_desc();
+ load_LDT(&init_mm.context);
+
+#ifdef CONFIG_KGDB
+ /*
+ * If the kgdb is connected no debug regs should be altered. This
+ * is only applicable when KGDB and a KGDB I/O module are built
+ * into the kernel and you are using early debugging with
+ * kgdbwait. KGDB will control the kernel HW breakpoint registers.
+ */
+ if (kgdb_connected && arch_kgdb_ops.correct_hw_break)
+ arch_kgdb_ops.correct_hw_break();
+ else {
+#endif
+ /*
+ * Clear all 6 debug registers:
+ */
+
+ set_debugreg(0UL, 0);
+ set_debugreg(0UL, 1);
+ set_debugreg(0UL, 2);
+ set_debugreg(0UL, 3);
+ set_debugreg(0UL, 6);
+ set_debugreg(0UL, 7);
+#ifdef CONFIG_KGDB
+ /* If the kgdb is connected no debug regs should be altered. */
+ }
+#endif
+
+ fpu_init();
+
+ raw_local_save_flags(kernel_eflags);
+
+ if (is_uv_system())
+ uv_cpu_init();
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-22 09:28:17 +0000