[PATCH 04/16] x86: cpu common let 64bit code have 32bit only func

From: Yinghai Lu
Date: Thu Sep 04 2008 - 23:10:41 EST


Signed-off-by: Yinghai Lu <yhlu.kernel@xxxxxxxxx>
---
arch/x86/kernel/cpu/common.c | 8 +++
arch/x86/kernel/cpu/common_64.c | 111 +++++++++++++++++++++++++++++++++++++++
2 files changed, 119 insertions(+), 0 deletions(-)

diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index e0ca51f..9128ba0 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -93,6 +93,7 @@ DEFINE_PER_CPU_PAGE_ALIGNED(struct gdt_page, gdt_page) = { .gdt = {
#endif
EXPORT_PER_CPU_SYMBOL_GPL(gdt_page);

+#ifdef CONFIG_X86_32
static int cachesize_override __cpuinitdata = -1;
static int disable_x86_serial_nr __cpuinitdata = 1;

@@ -195,6 +196,13 @@ static int __init x86_serial_nr_setup(char *s)
return 1;
}
__setup("serialnumber", x86_serial_nr_setup);
+#else
+/* Probe for the CPUID instruction */
+static inline int have_cpuid_p(void)
+{
+ return 1;
+}
+#endif

__u32 cleared_cpu_caps[NCAPINTS] __cpuinitdata;

diff --git a/arch/x86/kernel/cpu/common_64.c b/arch/x86/kernel/cpu/common_64.c
index b489050..40c9d89 100644
--- a/arch/x86/kernel/cpu/common_64.c
+++ b/arch/x86/kernel/cpu/common_64.c
@@ -92,6 +92,117 @@ DEFINE_PER_CPU_PAGE_ALIGNED(struct gdt_page, gdt_page) = { .gdt = {
#endif
EXPORT_PER_CPU_SYMBOL_GPL(gdt_page);

+#ifdef CONFIG_X86_32
+static int cachesize_override __cpuinitdata = -1;
+static int disable_x86_serial_nr __cpuinitdata = 1;
+
+static int __init cachesize_setup(char *str)
+{
+ get_option(&str, &cachesize_override);
+ return 1;
+}
+__setup("cachesize=", cachesize_setup);
+
+/*
+ * Naming convention should be: <Name> [(<Codename>)]
+ * This table only is used unless init_<vendor>() below doesn't set it;
+ * in particular, if CPUID levels 0x80000002..4 are supported, this isn't used
+ *
+ */
+
+/* Look up CPU names by table lookup. */
+static char __cpuinit *table_lookup_model(struct cpuinfo_x86 *c)
+{
+ struct cpu_model_info *info;
+
+ if (c->x86_model >= 16)
+ return NULL; /* Range check */
+
+ if (!this_cpu)
+ return NULL;
+
+ info = this_cpu->c_models;
+
+ while (info && info->family) {
+ if (info->family == c->x86)
+ return info->model_names[c->x86_model];
+ info++;
+ }
+ return NULL; /* Not found */
+}
+
+static int __init x86_fxsr_setup(char *s)
+{
+ setup_clear_cpu_cap(X86_FEATURE_FXSR);
+ setup_clear_cpu_cap(X86_FEATURE_XMM);
+ return 1;
+}
+__setup("nofxsr", x86_fxsr_setup);
+
+static int __init x86_sep_setup(char *s)
+{
+ setup_clear_cpu_cap(X86_FEATURE_SEP);
+ return 1;
+}
+__setup("nosep", x86_sep_setup);
+
+/* Standard macro to see if a specific flag is changeable */
+static inline int flag_is_changeable_p(u32 flag)
+{
+ u32 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 __cpuinit have_cpuid_p(void)
+{
+ return flag_is_changeable_p(X86_EFLAGS_ID);
+}
+
+static void __cpuinit squash_the_stupid_serial_number(struct cpuinfo_x86 *c)
+{
+ if (cpu_has(c, X86_FEATURE_PN) && disable_x86_serial_nr) {
+ /* Disable processor serial number */
+ unsigned long lo, hi;
+ rdmsr(MSR_IA32_BBL_CR_CTL, lo, hi);
+ lo |= 0x200000;
+ wrmsr(MSR_IA32_BBL_CR_CTL, lo, hi);
+ printk(KERN_NOTICE "CPU serial number disabled.\n");
+ clear_cpu_cap(c, X86_FEATURE_PN);
+
+ /* Disabling the serial number may affect the cpuid level */
+ c->cpuid_level = cpuid_eax(0);
+ }
+}
+
+static int __init x86_serial_nr_setup(char *s)
+{
+ disable_x86_serial_nr = 0;
+ return 1;
+}
+__setup("serialnumber", x86_serial_nr_setup);
+#else
+/* Probe for the CPUID instruction */
+static inline int have_cpuid_p(void)
+{
+ return 1;
+}
+#endif
+
__u32 cleared_cpu_caps[NCAPINTS] __cpuinitdata;

/* Current gdt points %fs at the "master" per-cpu area: after this,
--
1.5.4.5

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