x86/apic: Reuse apic_bsp_setup() for UP APIC setup

Extend apic_bsp_setup() so the same code flow can be used for
APIC_init_uniprocessor().

Folded Jiangs fix to provide proper ordering of the UP setup.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Link: http://lkml.kernel.org/r/20150115211704.084765674@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 22 insertions, 31 deletions

diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index 0a4107013ada..437c35bdddc8 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -2202,27 +2202,37 @@ void __init apic_set_eoi_write(void (*eoi_write)(u32 reg, u32 v))
         }
 }
 
-static void __init bsp_end_local_APIC_setup(void)
+static void __init apic_bsp_up_setup(void)
 {
-        end_local_APIC_setup();
+#ifdef CONFIG_X86_64
+        apic_write(APIC_ID, SET_APIC_ID(boot_cpu_physical_apicid));
+#else
         /*
-         * Now that local APIC setup is completed for BP, configure the fault
-         * handling for interrupt remapping.
+         * Hack: In case of kdump, after a crash, kernel might be booting
+         * on a cpu with non-zero lapic id. But boot_cpu_physical_apicid
+         * might be zero if read from MP tables. Get it from LAPIC.
          */
-        irq_remap_enable_fault_handling();
+# ifdef CONFIG_CRASH_DUMP
+        boot_cpu_physical_apicid = read_apic_id();
+# endif
+#endif
+        physid_set_mask_of_physid(boot_cpu_physical_apicid, &phys_cpu_present_map);
 }
 
 /**
  * apic_bsp_setup - Setup function for local apic and io-apic
+ * @upmode:             Force UP mode (for APIC_init_uniprocessor)
  *
  * Returns:
  * apic_id of BSP APIC
  */
-int __init apic_bsp_setup(void)
+int __init apic_bsp_setup(bool upmode)
 {
         int id;
 
         connect_bsp_APIC();
+        if (upmode)
+                apic_bsp_up_setup();
         setup_local_APIC();
 
         if (x2apic_mode)
@@ -2231,7 +2241,8 @@ int __init apic_bsp_setup(void)
                 id = GET_APIC_LOGICAL_ID(apic_read(APIC_LDR));
 
         enable_IO_APIC();
-        bsp_end_local_APIC_setup();
+        end_local_APIC_setup();
+        irq_remap_enable_fault_handling();
         setup_IO_APIC();
         return id;
 }
@@ -2267,32 +2278,12 @@ int __init APIC_init_uniprocessor(void)
         }
 #endif
 
-        default_setup_apic_routing();
+        if (!smp_found_config)
+                disable_ioapic_support();
 
+        default_setup_apic_routing();
         verify_local_APIC();
-        connect_bsp_APIC();
-
-#ifdef CONFIG_X86_64
-        apic_write(APIC_ID, SET_APIC_ID(boot_cpu_physical_apicid));
-#else
-        /*
-         * Hack: In case of kdump, after a crash, kernel might be booting
-         * on a cpu with non-zero lapic id. But boot_cpu_physical_apicid
-         * might be zero if read from MP tables. Get it from LAPIC.
-         */
-# ifdef CONFIG_CRASH_DUMP
-        boot_cpu_physical_apicid = read_apic_id();
-# endif
-#endif
-        physid_set_mask_of_physid(boot_cpu_physical_apicid, &phys_cpu_present_map);
-        setup_local_APIC();
-
-        if (smp_found_config)
-                enable_IO_APIC();
-
-        bsp_end_local_APIC_setup();
-
-        setup_IO_APIC();
+        apic_bsp_setup(true);
 
         x86_init.timers.setup_percpu_clockev();
         return 0;