}
/*
- * Setup extended LVT, AMD specific (K8, family 10h)
+ * Setup extended LVT, AMD specific
*
- * Vector mappings are hard coded. On K8 only offset 0 (APIC500) and
- * MCE interrupts are supported. Thus MCE offset must be set to 0.
+ * Software should use the LVT offsets the BIOS provides. The offsets
+ * are determined by the subsystems using it like those for MCE
+ * threshold or IBS. On K8 only offset 0 (APIC500) and MCE interrupts
+ * are supported. Beginning with family 10h at least 4 offsets are
+ * available.
*
- * If mask=1, the LVT entry does not generate interrupts while mask=0
- * enables the vector. See also the BKDGs.
+ * Since the offsets must be consistent for all cores, we keep track
+ * of the LVT offsets in software and reserve the offset for the same
+ * vector also to be used on other cores. An offset is freed by
+ * setting the entry to APIC_EILVT_MASKED.
+ *
+ * If the BIOS is right, there should be no conflicts. Otherwise a
+ * "[Firmware Bug]: ..." error message is generated. However, if
+ * software does not properly determines the offsets, it is not
+ * necessarily a BIOS bug.
*/
-#define APIC_EILVT_LVTOFF_MCE 0
-#define APIC_EILVT_LVTOFF_IBS 1
+static atomic_t eilvt_offsets[APIC_EILVT_NR_MAX];
-static void setup_APIC_eilvt(u8 lvt_off, u8 vector, u8 msg_type, u8 mask)
+static inline int eilvt_entry_is_changeable(unsigned int old, unsigned int new)
{
- unsigned long reg = (lvt_off << 4) + APIC_EILVTn(0);
- unsigned int v = (mask << 16) | (msg_type << 8) | vector;
-
- apic_write(reg, v);
+ return (old & APIC_EILVT_MASKED)
+ || (new == APIC_EILVT_MASKED)
+ || ((new & ~APIC_EILVT_MASKED) == old);
}
-u8 setup_APIC_eilvt_mce(u8 vector, u8 msg_type, u8 mask)
+static unsigned int reserve_eilvt_offset(int offset, unsigned int new)
{
- setup_APIC_eilvt(APIC_EILVT_LVTOFF_MCE, vector, msg_type, mask);
- return APIC_EILVT_LVTOFF_MCE;
+ unsigned int rsvd; /* 0: uninitialized */
+
+ if (offset >= APIC_EILVT_NR_MAX)
+ return ~0;
+
+ rsvd = atomic_read(&eilvt_offsets[offset]) & ~APIC_EILVT_MASKED;
+ do {
+ if (rsvd &&
+ !eilvt_entry_is_changeable(rsvd, new))
+ /* may not change if vectors are different */
+ return rsvd;
+ rsvd = atomic_cmpxchg(&eilvt_offsets[offset], rsvd, new);
+ } while (rsvd != new);
+
+ return new;
}
-u8 setup_APIC_eilvt_ibs(u8 vector, u8 msg_type, u8 mask)
+/*
+ * If mask=1, the LVT entry does not generate interrupts while mask=0
+ * enables the vector. See also the BKDGs.
+ */
+
+int setup_APIC_eilvt(u8 offset, u8 vector, u8 msg_type, u8 mask)
{
- setup_APIC_eilvt(APIC_EILVT_LVTOFF_IBS, vector, msg_type, mask);
- return APIC_EILVT_LVTOFF_IBS;
+ unsigned long reg = APIC_EILVTn(offset);
+ unsigned int new, old, reserved;
+
+ new = (mask << 16) | (msg_type << 8) | vector;
+ old = apic_read(reg);
+ reserved = reserve_eilvt_offset(offset, new);
+
+ if (reserved != new) {
+ pr_err(FW_BUG "cpu %d, try to setup vector 0x%x, but "
+ "vector 0x%x was already reserved by another core, "
+ "APIC%lX=0x%x\n",
+ smp_processor_id(), new, reserved, reg, old);
+ return -EINVAL;
+ }
+
+ if (!eilvt_entry_is_changeable(old, new)) {
+ pr_err(FW_BUG "cpu %d, try to setup vector 0x%x but "
+ "register already in use, APIC%lX=0x%x\n",
+ smp_processor_id(), new, reg, old);
+ return -EBUSY;
+ }
+
+ apic_write(reg, new);
+
+ return 0;
}
-EXPORT_SYMBOL_GPL(setup_APIC_eilvt_ibs);
+EXPORT_SYMBOL_GPL(setup_APIC_eilvt);
/*
* Program the next event, relative to now
return 0;
}
#else
+
+static int apic_verify(void)
+{
+ u32 features, h, l;
+
+ /*
+ * The APIC feature bit should now be enabled
+ * in `cpuid'
+ */
+ features = cpuid_edx(1);
+ if (!(features & (1 << X86_FEATURE_APIC))) {
+ pr_warning("Could not enable APIC!\n");
+ return -1;
+ }
+ set_cpu_cap(&boot_cpu_data, X86_FEATURE_APIC);
+ mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
+
+ /* The BIOS may have set up the APIC at some other address */
+ rdmsr(MSR_IA32_APICBASE, l, h);
+ if (l & MSR_IA32_APICBASE_ENABLE)
+ mp_lapic_addr = l & MSR_IA32_APICBASE_BASE;
+
+ pr_info("Found and enabled local APIC!\n");
+ return 0;
+}
+
+int apic_force_enable(void)
+{
+ u32 h, l;
+
+ if (disable_apic)
+ return -1;
+
+ /*
+ * Some BIOSes disable the local APIC in the APIC_BASE
+ * MSR. This can only be done in software for Intel P6 or later
+ * and AMD K7 (Model > 1) or later.
+ */
+ rdmsr(MSR_IA32_APICBASE, l, h);
+ if (!(l & MSR_IA32_APICBASE_ENABLE)) {
+ pr_info("Local APIC disabled by BIOS -- reenabling.\n");
+ l &= ~MSR_IA32_APICBASE_BASE;
+ l |= MSR_IA32_APICBASE_ENABLE | APIC_DEFAULT_PHYS_BASE;
+ wrmsr(MSR_IA32_APICBASE, l, h);
+ enabled_via_apicbase = 1;
+ }
+ return apic_verify();
+}
+
/*
* Detect and initialize APIC
*/
static int __init detect_init_APIC(void)
{
- u32 h, l, features;
-
/* Disabled by kernel option? */
if (disable_apic)
return -1;
"you can enable it with \"lapic\"\n");
return -1;
}
- /*
- * Some BIOSes disable the local APIC in the APIC_BASE
- * MSR. This can only be done in software for Intel P6 or later
- * and AMD K7 (Model > 1) or later.
- */
- rdmsr(MSR_IA32_APICBASE, l, h);
- if (!(l & MSR_IA32_APICBASE_ENABLE)) {
- pr_info("Local APIC disabled by BIOS -- reenabling.\n");
- l &= ~MSR_IA32_APICBASE_BASE;
- l |= MSR_IA32_APICBASE_ENABLE | APIC_DEFAULT_PHYS_BASE;
- wrmsr(MSR_IA32_APICBASE, l, h);
- enabled_via_apicbase = 1;
- }
- }
- /*
- * The APIC feature bit should now be enabled
- * in `cpuid'
- */
- features = cpuid_edx(1);
- if (!(features & (1 << X86_FEATURE_APIC))) {
- pr_warning("Could not enable APIC!\n");
- return -1;
+ if (apic_force_enable())
+ return -1;
+ } else {
+ if (apic_verify())
+ return -1;
}
- set_cpu_cap(&boot_cpu_data, X86_FEATURE_APIC);
- mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
-
- /* The BIOS may have set up the APIC at some other address */
- rdmsr(MSR_IA32_APICBASE, l, h);
- if (l & MSR_IA32_APICBASE_ENABLE)
- mp_lapic_addr = l & MSR_IA32_APICBASE_BASE;
-
- pr_info("Found and enabled local APIC!\n");
apic_pm_activate();
}
#endif
-#ifndef CONFIG_SMP
- enable_IR_x2apic();
default_setup_apic_routing();
-#endif
verify_local_APIC();
connect_bsp_APIC();