[PATCH] i386: move apic init in init_IRQs

All kinds of ugliness exists because we don't initialize
the apics during init_IRQs.
- We calibrate jiffies in non apic mode even when we are using apics.
- We have to have special code to initialize the apics when non-smp.
- The legacy i8259 must exist and be setup correctly, even
  when we won't use it past initialization.
- The kexec on panic code must restore the state of the io_apics.
- init/main.c needs a special case for !smp smp_init on x86

In addition to pure code movement I needed a couple
of non-obvious changes:
- Move setup_boot_APIC_clock into APIC_late_time_init for
  simplicity.
- Use cpu_khz to generate a better approximation of loops_per_jiffies
  so I can verify the timer interrupt is working.
- Call setup_apic_nmi_watchdog again after cpu_khz is initialized on
  the boot cpu.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/arch/i386/kernel/apic.c b/arch/i386/kernel/apic.c
index 5546dde..8d81b7b 100644 (file)
--- a/arch/i386/kernel/apic.c
+++ b/arch/i386/kernel/apic.c
@@ -803,6 +803,7 @@ no_apic:
 
 void __init init_apic_mappings(void)
 {
+       unsigned int orig_apicid;
        unsigned long apic_phys;
 
        /*
@@ -824,8 +825,11 @@ void __init init_apic_mappings(void)
         * Fetch the APIC ID of the BSP in case we have a
         * default configuration (or the MP table is broken).
         */
-       if (boot_cpu_physical_apicid == -1U)
-               boot_cpu_physical_apicid = GET_APIC_ID(apic_read(APIC_ID));
+       orig_apicid = boot_cpu_physical_apicid;
+       boot_cpu_physical_apicid = GET_APIC_ID(apic_read(APIC_ID));
+       if ((orig_apicid != -1U) && (orig_apicid != boot_cpu_physical_apicid))
+               printk(KERN_WARNING "Boot APIC ID in local APIC unexpected (%d vs %d)",
+                       orig_apicid, boot_cpu_physical_apicid);
 
 #ifdef CONFIG_X86_IO_APIC
        {
@@ -1046,9 +1050,11 @@ static unsigned int calibration_result;
 
 void __init setup_boot_APIC_clock(void)
 {
+       unsigned long flags;
        apic_printk(APIC_VERBOSE, "Using local APIC timer interrupts.\n");
        using_apic_timer = 1;
 
+       local_irq_save(flags);
        local_irq_disable();
 
        calibration_result = calibrate_APIC_clock();
@@ -1057,7 +1063,7 @@ void __init setup_boot_APIC_clock(void)
         */
        setup_APIC_timer(calibration_result);
 
-       local_irq_enable();
+       local_irq_restore(flags);
 }
 
 void __devinit setup_secondary_APIC_clock(void)
@@ -1254,40 +1260,81 @@ fastcall void smp_error_interrupt(struct pt_regs *regs)
 }
 
 /*
- * This initializes the IO-APIC and APIC hardware if this is
- * a UP kernel.
+ * This initializes the IO-APIC and APIC hardware.
  */
-int __init APIC_init_uniprocessor (void)
+int __init APIC_init(void)
 {
-       if (enable_local_apic < 0)
-               clear_bit(X86_FEATURE_APIC, boot_cpu_data.x86_capability);
+       if (enable_local_apic < 0) {
+               printk(KERN_INFO "APIC disabled\n");
+               return -1;
+       }
 
-       if (!smp_found_config && !cpu_has_apic)
+       /* See if we have a SMP configuration or have forced enabled
+        * the local apic.
+        */
+       if (!smp_found_config && !acpi_lapic && !cpu_has_apic) {
+               enable_local_apic = -1;
                return -1;
+       }
 
        /*
-        * Complain if the BIOS pretends there is one.
+        * Complain if the BIOS pretends there is an apic.
+        * Then get out because we don't have an a local apic.
         */
        if (!cpu_has_apic && APIC_INTEGRATED(apic_version[boot_cpu_physical_apicid])) {
                printk(KERN_ERR "BIOS bug, local APIC #%d not detected!...\n",
                        boot_cpu_physical_apicid);
+               printk(KERN_ERR "... forcing use of dummy APIC emulation. (tell your hw vendor)\n");
+               enable_local_apic = -1;
                return -1;
        }
 
        verify_local_APIC();
 
+       /*
+        * Should not be necessary because the MP table should list the boot
+        * CPU too, but we do it for the sake of robustness anyway.
+        * Makes no sense to do this check in clustered apic mode, so skip it
+        */
+       if (!check_phys_apicid_present(boot_cpu_physical_apicid)) {
+               printk("weird, boot CPU (#%d) not listed by the BIOS.\n",
+                               boot_cpu_physical_apicid);
+               physid_set(hard_smp_processor_id(), phys_cpu_present_map);
+       }
+
+       /*
+        * Switch from PIC to APIC mode.
+        */
        connect_bsp_APIC();
+       setup_local_APIC();
 
-       phys_cpu_present_map = physid_mask_of_physid(boot_cpu_physical_apicid);
+#ifdef CONFIG_X86_IO_APIC
+       /*
+        * Now start the IO-APICs
+        */
+       if (smp_found_config && !skip_ioapic_setup && nr_ioapics)
+               setup_IO_APIC();
+#endif
+       return 0;
+}
 
-       setup_local_APIC();
+void __init APIC_late_time_init(void)
+{
+       /* Improve our loops per jiffy estimate */
+       loops_per_jiffy = ((1000 + HZ - 1)/HZ)*cpu_khz;
+       boot_cpu_data.loops_per_jiffy = loops_per_jiffy;
+       cpu_data[0].loops_per_jiffy = loops_per_jiffy;
+
+       /* setup_apic_nmi_watchdog doesn't work properly before cpu_khz is
+        * initialized.  So redo it here to ensure the boot cpu is setup
+        * properly.
+        */
+       if (nmi_watchdog == NMI_LOCAL_APIC)
+               setup_apic_nmi_watchdog();
 
 #ifdef CONFIG_X86_IO_APIC
-       if (smp_found_config)
-               if (!skip_ioapic_setup && nr_ioapics)
-                       setup_IO_APIC();
+       if (smp_found_config && !skip_ioapic_setup && nr_ioapics)
+               IO_APIC_late_time_init();
 #endif
        setup_boot_APIC_clock();
-
-       return 0;
 }

diff --git a/arch/i386/kernel/i8259.c b/arch/i386/kernel/i8259.c
index 323ef8a..d86f249 100644 (file)
--- a/arch/i386/kernel/i8259.c
+++ b/arch/i386/kernel/i8259.c
@@ -435,4 +435,8 @@ void __init init_IRQ(void)
                setup_irq(FPU_IRQ, &fpu_irq);
 
        irq_ctx_init(smp_processor_id());
+
+#ifdef CONFIG_X86_LOCAL_APIC
+       APIC_init();
+#endif
 }

diff --git a/arch/i386/kernel/io_apic.c b/arch/i386/kernel/io_apic.c
index cc5d7ac..5a77c52 100644 (file)
--- a/arch/i386/kernel/io_apic.c
+++ b/arch/i386/kernel/io_apic.c
@@ -2387,11 +2387,15 @@ void __init setup_IO_APIC(void)
        sync_Arb_IDs();
        setup_IO_APIC_irqs();
        init_IO_APIC_traps();
-       check_timer();
        if (!acpi_ioapic)
                print_IO_APIC();
 }
 
+void __init IO_APIC_late_time_init(void)
+{
+       check_timer();
+}
+
 /*
  *     Called after all the initialization is done. If we didnt find any
  *     APIC bugs then we can allow the modify fast path

diff --git a/arch/i386/kernel/smpboot.c b/arch/i386/kernel/smpboot.c
index 01b618e..5a2bbe0 100644 (file)
--- a/arch/i386/kernel/smpboot.c
+++ b/arch/i386/kernel/smpboot.c
@@ -1078,6 +1078,16 @@ void *xquad_portio;
 EXPORT_SYMBOL(xquad_portio);
 #endif
 
+/*
+ * Fall back to non SMP mode after errors.
+ *
+ */
+static __init void disable_smp(void)
+{
+       cpu_set(0, cpu_sibling_map[0]);
+       cpu_set(0, cpu_core_map[0]);
+}
+
 static void __init smp_boot_cpus(unsigned int max_cpus)
 {
        int apicid, cpu, bit, kicked;
@@ -1090,7 +1100,6 @@ static void __init smp_boot_cpus(unsigned int max_cpus)
        printk("CPU%d: ", 0);
        print_cpu_info(&cpu_data[0]);
 
-       boot_cpu_physical_apicid = GET_APIC_ID(apic_read(APIC_ID));
        boot_cpu_logical_apicid = logical_smp_processor_id();
        x86_cpu_to_apicid[0] = boot_cpu_physical_apicid;
 
@@ -1102,68 +1111,27 @@ static void __init smp_boot_cpus(unsigned int max_cpus)
        cpus_clear(cpu_core_map[0]);
        cpu_set(0, cpu_core_map[0]);
 
+       map_cpu_to_logical_apicid();
+
        /*
         * If we couldn't find an SMP configuration at boot time,
         * get out of here now!
         */
        if (!smp_found_config && !acpi_lapic) {
                printk(KERN_NOTICE "SMP motherboard not detected.\n");
-               smpboot_clear_io_apic_irqs();
-               phys_cpu_present_map = physid_mask_of_physid(0);
-               if (APIC_init_uniprocessor())
-                       printk(KERN_NOTICE "Local APIC not detected."
-                                          " Using dummy APIC emulation.\n");
-               map_cpu_to_logical_apicid();
-               cpu_set(0, cpu_sibling_map[0]);
-               cpu_set(0, cpu_core_map[0]);
-               return;
-       }
-
-       /*
-        * Should not be necessary because the MP table should list the boot
-        * CPU too, but we do it for the sake of robustness anyway.
-        * Makes no sense to do this check in clustered apic mode, so skip it
-        */
-       if (!check_phys_apicid_present(boot_cpu_physical_apicid)) {
-               printk("weird, boot CPU (#%d) not listed by the BIOS.\n",
-                               boot_cpu_physical_apicid);
-               physid_set(hard_smp_processor_id(), phys_cpu_present_map);
-       }
-
-       /*
-        * If we couldn't find a local APIC, then get out of here now!
-        */
-       if (APIC_INTEGRATED(apic_version[boot_cpu_physical_apicid]) && !cpu_has_apic) {
-               printk(KERN_ERR "BIOS bug, local APIC #%d not detected!...\n",
-                       boot_cpu_physical_apicid);
-               printk(KERN_ERR "... forcing use of dummy APIC emulation. (tell your hw vendor)\n");
-               smpboot_clear_io_apic_irqs();
-               phys_cpu_present_map = physid_mask_of_physid(0);
-               cpu_set(0, cpu_sibling_map[0]);
-               cpu_set(0, cpu_core_map[0]);
+               disable_smp();
                return;
        }
 
-       verify_local_APIC();
-
        /*
         * If SMP should be disabled, then really disable it!
         */
-       if (!max_cpus) {
-               smp_found_config = 0;
-               printk(KERN_INFO "SMP mode deactivated, forcing use of dummy APIC emulation.\n");
-               smpboot_clear_io_apic_irqs();
-               phys_cpu_present_map = physid_mask_of_physid(0);
-               cpu_set(0, cpu_sibling_map[0]);
-               cpu_set(0, cpu_core_map[0]);
+       if (!max_cpus || (enable_local_apic < 0)) {
+               printk(KERN_INFO "SMP mode deactivated.\n");
+               disable_smp();
                return;
        }
 
-       connect_bsp_APIC();
-       setup_local_APIC();
-       map_cpu_to_logical_apicid();
-
-
        setup_portio_remap();
 
        /*
@@ -1244,10 +1212,6 @@ static void __init smp_boot_cpus(unsigned int max_cpus)
        cpu_set(0, cpu_sibling_map[0]);
        cpu_set(0, cpu_core_map[0]);
 
-       smpboot_setup_io_apic();
-
-       setup_boot_APIC_clock();
-
        /*
         * Synchronize the TSC with the AP
         */

diff --git a/arch/i386/kernel/time.c b/arch/i386/kernel/time.c
index 2883a4d..46c35ec 100644 (file)
--- a/arch/i386/kernel/time.c
+++ b/arch/i386/kernel/time.c
@@ -444,8 +444,8 @@ static int time_init_device(void)
 
 device_initcall(time_init_device);
 
-#ifdef CONFIG_HPET_TIMER
 extern void (*late_time_init)(void);
+#ifdef CONFIG_HPET_TIMER
 /* Duplicate of time_init() below, with hpet_enable part added */
 static void __init hpet_time_init(void)
 {
@@ -462,6 +462,11 @@ static void __init hpet_time_init(void)
        printk(KERN_INFO "Using %s for high-res timesource\n",cur_timer->name);
 
        time_init_hook();
+
+#ifdef CONFIG_X86_LOCAL_APIC
+       if (enable_local_apic >= 0)
+               APIC_late_time_init();
+#endif
 }
 #endif
 
@@ -486,4 +491,9 @@ void __init time_init(void)
        printk(KERN_INFO "Using %s for high-res timesource\n",cur_timer->name);
 
        time_init_hook();
+
+#ifdef CONFIG_X86_LOCAL_APIC
+       if (enable_local_apic >= 0)
+               late_time_init = APIC_late_time_init;
+#endif
 }

diff --git a/include/asm-i386/apic.h b/include/asm-i386/apic.h
index 8c454aa..a515e2a 100644 (file)
--- a/include/asm-i386/apic.h
+++ b/include/asm-i386/apic.h
@@ -118,7 +118,8 @@ extern void release_lapic_nmi(void);
 extern void disable_timer_nmi_watchdog(void);
 extern void enable_timer_nmi_watchdog(void);
 extern void nmi_watchdog_tick (struct pt_regs * regs);
-extern int APIC_init_uniprocessor (void);
+extern int APIC_init(void);
+extern void APIC_late_time_init(void);
 extern void disable_APIC_timer(void);
 extern void enable_APIC_timer(void);
 

diff --git a/include/asm-i386/hw_irq.h b/include/asm-i386/hw_irq.h
index 622815b..9139b89 100644 (file)
--- a/include/asm-i386/hw_irq.h
+++ b/include/asm-i386/hw_irq.h
@@ -55,6 +55,7 @@ void init_8259A(int aeoi);
 void FASTCALL(send_IPI_self(int vector));
 void init_VISWS_APIC_irqs(void);
 void setup_IO_APIC(void);
+void IO_APIC_late_time_init(void);
 void disable_IO_APIC(void);
 void print_IO_APIC(void);
 int IO_APIC_get_PCI_irq_vector(int bus, int slot, int fn);

diff --git a/include/asm-i386/mach-default/smpboot_hooks.h b/include/asm-i386/mach-default/smpboot_hooks.h
index 7f45f63..d7c70c1 100644 (file)
--- a/include/asm-i386/mach-default/smpboot_hooks.h
+++ b/include/asm-i386/mach-default/smpboot_hooks.h
@@ -1,11 +1,6 @@
 /* two abstractions specific to kernel/smpboot.c, mainly to cater to visws
  * which needs to alter them. */
 
-static inline void smpboot_clear_io_apic_irqs(void)
-{
-       io_apic_irqs = 0;
-}
-
 static inline void smpboot_setup_warm_reset_vector(unsigned long start_eip)
 {
        CMOS_WRITE(0xa, 0xf);
@@ -32,13 +27,3 @@ static inline void smpboot_restore_warm_reset_vector(void)
 
        *((volatile long *) phys_to_virt(0x467)) = 0;
 }
-
-static inline void smpboot_setup_io_apic(void)
-{
-       /*
-        * Here we can be sure that there is an IO-APIC in the system. Let's
-        * go and set it up:
-        */
-       if (!skip_ioapic_setup && nr_ioapics)
-               setup_IO_APIC();
-}

diff --git a/include/asm-i386/mach-visws/smpboot_hooks.h b/include/asm-i386/mach-visws/smpboot_hooks.h
index d926471..14d8e03 100644 (file)
--- a/include/asm-i386/mach-visws/smpboot_hooks.h
+++ b/include/asm-i386/mach-visws/smpboot_hooks.h
@@ -11,14 +11,7 @@ static inline void smpboot_setup_warm_reset_vector(unsigned long start_eip)
 
 /* for visws do nothing for any of these */
 
-static inline void smpboot_clear_io_apic_irqs(void)
-{
-}
-
 static inline void smpboot_restore_warm_reset_vector(void)
 {
 }
 
-static inline void smpboot_setup_io_apic(void)
-{
-}

diff --git a/init/main.c b/init/main.c
index f142d40..4075d97 100644 (file)
--- a/init/main.c
+++ b/init/main.c
@@ -64,10 +64,6 @@
 #endif
 #endif
 
-#ifdef CONFIG_X86_LOCAL_APIC
-#include <asm/smp.h>
-#endif
-
 /*
  * Versions of gcc older than that listed below may actually compile
  * and link okay, but the end product can have subtle run time bugs.
@@ -314,14 +310,7 @@ extern void setup_arch(char **);
 
 #ifndef CONFIG_SMP
 
-#ifdef CONFIG_X86_LOCAL_APIC
-static void __init smp_init(void)
-{
-       APIC_init_uniprocessor();
-}
-#else
 #define smp_init()     do { } while (0)
-#endif
 
 static inline void setup_per_cpu_areas(void) { }
 static inline void smp_prepare_cpus(unsigned int maxcpus) { }