target-i386: Move APIC ID compatibility code to pc.c

The APIC ID compatibility code is required only for PC, and now that
x86_cpu_initfn() doesn't use x86_cpu_apic_id_from_index() anymore, that
code can be moved to pc.c.

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>

1 files changed, 35 insertions, 0 deletions

diff --git a/hw/i386/pc.c b/hw/i386/pc.c
index 79eaad5..b5b2aad 100644
--- a/hw/i386/pc.c
+++ b/hw/i386/pc.c
@@ -25,6 +25,8 @@
 #include "hw/i386/pc.h"
 #include "hw/char/serial.h"
 #include "hw/i386/apic.h"
+#include "hw/i386/topology.h"
+#include "sysemu/cpus.h"
 #include "hw/block/fdc.h"
 #include "hw/ide.h"
 #include "hw/pci/pci.h"
@@ -629,6 +631,39 @@ bool e820_get_entry(int idx, uint32_t type, uint64_t *address, uint64_t *length)
     return false;
 }
 
+/* Enables contiguous-apic-ID mode, for compatibility */
+static bool compat_apic_id_mode;
+
+void enable_compat_apic_id_mode(void)
+{
+    compat_apic_id_mode = true;
+}
+
+/* Calculates initial APIC ID for a specific CPU index
+ *
+ * Currently we need to be able to calculate the APIC ID from the CPU index
+ * alone (without requiring a CPU object), as the QEMU<->Seabios interfaces have
+ * no concept of "CPU index", and the NUMA tables on fw_cfg need the APIC ID of
+ * all CPUs up to max_cpus.
+ */
+static uint32_t x86_cpu_apic_id_from_index(unsigned int cpu_index)
+{
+    uint32_t correct_id;
+    static bool warned;
+
+    correct_id = x86_apicid_from_cpu_idx(smp_cores, smp_threads, cpu_index);
+    if (compat_apic_id_mode) {
+        if (cpu_index != correct_id && !warned) {
+            error_report("APIC IDs set in compatibility mode, "
+                         "CPU topology won't match the configuration");
+            warned = true;
+        }
+        return cpu_index;
+    } else {
+        return correct_id;
+    }
+}
+
 /* Calculates the limit to CPU APIC ID values
  *
  * This function returns the limit for the APIC ID value, so that all