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path: root/arch/i386/kernel/cpu/mtrr/main.c
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Diffstat (limited to 'arch/i386/kernel/cpu/mtrr/main.c')
-rw-r--r--arch/i386/kernel/cpu/mtrr/main.c76
1 files changed, 53 insertions, 23 deletions
diff --git a/arch/i386/kernel/cpu/mtrr/main.c b/arch/i386/kernel/cpu/mtrr/main.c
index d66b09e0c82..764cac64e21 100644
--- a/arch/i386/kernel/cpu/mtrr/main.c
+++ b/arch/i386/kernel/cpu/mtrr/main.c
@@ -332,6 +332,8 @@ int mtrr_add_page(unsigned long base, unsigned long size,
error = -EINVAL;
+ /* No CPU hotplug when we change MTRR entries */
+ lock_cpu_hotplug();
/* Search for existing MTRR */
down(&main_lock);
for (i = 0; i < num_var_ranges; ++i) {
@@ -372,6 +374,7 @@ int mtrr_add_page(unsigned long base, unsigned long size,
error = i;
out:
up(&main_lock);
+ unlock_cpu_hotplug();
return error;
}
@@ -461,6 +464,8 @@ int mtrr_del_page(int reg, unsigned long base, unsigned long size)
return -ENXIO;
max = num_var_ranges;
+ /* No CPU hotplug when we change MTRR entries */
+ lock_cpu_hotplug();
down(&main_lock);
if (reg < 0) {
/* Search for existing MTRR */
@@ -501,6 +506,7 @@ int mtrr_del_page(int reg, unsigned long base, unsigned long size)
error = reg;
out:
up(&main_lock);
+ unlock_cpu_hotplug();
return error;
}
/**
@@ -544,21 +550,9 @@ static void __init init_ifs(void)
centaur_init_mtrr();
}
-static void __init init_other_cpus(void)
-{
- if (use_intel())
- get_mtrr_state();
-
- /* bring up the other processors */
- set_mtrr(~0U,0,0,0);
-
- if (use_intel()) {
- finalize_mtrr_state();
- mtrr_state_warn();
- }
-}
-
-
+/* The suspend/resume methods are only for CPU without MTRR. CPU using generic
+ * MTRR driver doesn't require this
+ */
struct mtrr_value {
mtrr_type ltype;
unsigned long lbase;
@@ -611,13 +605,13 @@ static struct sysdev_driver mtrr_sysdev_driver = {
/**
- * mtrr_init - initialize mtrrs on the boot CPU
+ * mtrr_bp_init - initialize mtrrs on the boot CPU
*
* This needs to be called early; before any of the other CPUs are
* initialized (i.e. before smp_init()).
*
*/
-static int __init mtrr_init(void)
+void __init mtrr_bp_init(void)
{
init_ifs();
@@ -674,12 +668,48 @@ static int __init mtrr_init(void)
if (mtrr_if) {
set_num_var_ranges();
init_table();
- init_other_cpus();
-
- return sysdev_driver_register(&cpu_sysdev_class,
- &mtrr_sysdev_driver);
+ if (use_intel())
+ get_mtrr_state();
}
- return -ENXIO;
}
-subsys_initcall(mtrr_init);
+void mtrr_ap_init(void)
+{
+ unsigned long flags;
+
+ if (!mtrr_if || !use_intel())
+ return;
+ /*
+ * Ideally we should hold main_lock here to avoid mtrr entries changed,
+ * but this routine will be called in cpu boot time, holding the lock
+ * breaks it. This routine is called in two cases: 1.very earily time
+ * of software resume, when there absolutely isn't mtrr entry changes;
+ * 2.cpu hotadd time. We let mtrr_add/del_page hold cpuhotplug lock to
+ * prevent mtrr entry changes
+ */
+ local_irq_save(flags);
+
+ mtrr_if->set_all();
+
+ local_irq_restore(flags);
+}
+
+static int __init mtrr_init_finialize(void)
+{
+ if (!mtrr_if)
+ return 0;
+ if (use_intel())
+ mtrr_state_warn();
+ else {
+ /* The CPUs haven't MTRR and seemes not support SMP. They have
+ * specific drivers, we use a tricky method to support
+ * suspend/resume for them.
+ * TBD: is there any system with such CPU which supports
+ * suspend/resume? if no, we should remove the code.
+ */
+ sysdev_driver_register(&cpu_sysdev_class,
+ &mtrr_sysdev_driver);
+ }
+ return 0;
+}
+subsys_initcall(mtrr_init_finialize);