x86, ioapic: Consolidate the explicit EOI code

Consolidate the io-apic EOI code in clear_IO_APIC_pin() and
eoi_ioapic_irq().

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Thomas Renninger <trenn@suse.de>
Cc: Rafael Wysocki <rjw@novell.com>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Cc: lchiquitto@novell.com
Cc: jbeulich@novell.com
Cc: yinghai@kernel.org
Link: http://lkml.kernel.org/r/20110825190657.259696697@sbsiddha-desk.sc.intel.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 65 insertions, 74 deletions

diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index 85050c9ab755..229e19f3eb57 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -581,6 +581,66 @@ static void unmask_ioapic_irq(struct irq_data *data)
         unmask_ioapic(data->chip_data);
 }
 
+/*
+ * IO-APIC versions below 0x20 don't support EOI register.
+ * For the record, here is the information about various versions:
+ *     0Xh     82489DX
+ *     1Xh     I/OAPIC or I/O(x)APIC which are not PCI 2.2 Compliant
+ *     2Xh     I/O(x)APIC which is PCI 2.2 Compliant
+ *     30h-FFh Reserved
+ *
+ * Some of the Intel ICH Specs (ICH2 to ICH5) documents the io-apic
+ * version as 0x2. This is an error with documentation and these ICH chips
+ * use io-apic's of version 0x20.
+ *
+ * For IO-APIC's with EOI register, we use that to do an explicit EOI.
+ * Otherwise, we simulate the EOI message manually by changing the trigger
+ * mode to edge and then back to level, with RTE being masked during this.
+ */
+static void __eoi_ioapic_pin(int apic, int pin, int vector, struct irq_cfg *cfg)
+{
+        if (mpc_ioapic_ver(apic) >= 0x20) {
+                /*
+                 * Intr-remapping uses pin number as the virtual vector
+                 * in the RTE. Actual vector is programmed in
+                 * intr-remapping table entry. Hence for the io-apic
+                 * EOI we use the pin number.
+                 */
+                if (cfg && irq_remapped(cfg))
+                        io_apic_eoi(apic, pin);
+                else
+                        io_apic_eoi(apic, vector);
+        } else {
+                struct IO_APIC_route_entry entry, entry1;
+
+                entry = entry1 = __ioapic_read_entry(apic, pin);
+
+                /*
+                 * Mask the entry and change the trigger mode to edge.
+                 */
+                entry1.mask = 1;
+                entry1.trigger = IOAPIC_EDGE;
+
+                __ioapic_write_entry(apic, pin, entry1);
+
+                /*
+                 * Restore the previous level triggered entry.
+                 */
+                __ioapic_write_entry(apic, pin, entry);
+        }
+}
+
+static void eoi_ioapic_irq(unsigned int irq, struct irq_cfg *cfg)
+{
+        struct irq_pin_list *entry;
+        unsigned long flags;
+
+        raw_spin_lock_irqsave(&ioapic_lock, flags);
+        for_each_irq_pin(entry, cfg->irq_2_pin)
+                __eoi_ioapic_pin(entry->apic, entry->pin, cfg->vector, cfg);
+        raw_spin_unlock_irqrestore(&ioapic_lock, flags);
+}
+
 static void clear_IO_APIC_pin(unsigned int apic, unsigned int pin)
 {
         struct IO_APIC_route_entry entry;
@@ -601,6 +661,8 @@ static void clear_IO_APIC_pin(unsigned int apic, unsigned int pin)
         }
 
         if (entry.irr) {
+                unsigned long flags;
+
                 /*
                  * Make sure the trigger mode is set to level. Explicit EOI
                  * doesn't clear the remote-IRR if the trigger mode is not
@@ -611,23 +673,9 @@ static void clear_IO_APIC_pin(unsigned int apic, unsigned int pin)
                         ioapic_write_entry(apic, pin, entry);
                 }
 
-                if (mpc_ioapic_ver(apic) >= 0x20) {
-                        unsigned long flags;
-
-                        raw_spin_lock_irqsave(&ioapic_lock, flags);
-                        io_apic_eoi(apic, entry.vector);
-                        raw_spin_unlock_irqrestore(&ioapic_lock, flags);
-                } else {
-                        /*
-                         * Mechanism by which we clear remote-IRR in this
-                         * case is by changing the trigger mode to edge and
-                         * back to level.
-                         */
-                        entry.trigger = IOAPIC_EDGE;
-                        ioapic_write_entry(apic, pin, entry);
-                        entry.trigger = IOAPIC_LEVEL;
-                        ioapic_write_entry(apic, pin, entry);
-                }
+                raw_spin_lock_irqsave(&ioapic_lock, flags);
+                __eoi_ioapic_pin(apic, pin, entry.vector, NULL);
+                raw_spin_unlock_irqrestore(&ioapic_lock, flags);
         }
 
         /*
@@ -2457,63 +2505,6 @@ static void ack_apic_edge(struct irq_data *data)
 
 atomic_t irq_mis_count;
 
-/*
- * IO-APIC versions below 0x20 don't support EOI register.
- * For the record, here is the information about various versions:
- *     0Xh     82489DX
- *     1Xh     I/OAPIC or I/O(x)APIC which are not PCI 2.2 Compliant
- *     2Xh     I/O(x)APIC which is PCI 2.2 Compliant
- *     30h-FFh Reserved
- *
- * Some of the Intel ICH Specs (ICH2 to ICH5) documents the io-apic
- * version as 0x2. This is an error with documentation and these ICH chips
- * use io-apic's of version 0x20.
- *
- * For IO-APIC's with EOI register, we use that to do an explicit EOI.
- * Otherwise, we simulate the EOI message manually by changing the trigger
- * mode to edge and then back to level, with RTE being masked during this.
-*/
-static void eoi_ioapic_irq(unsigned int irq, struct irq_cfg *cfg)
-{
-        struct irq_pin_list *entry;
-        unsigned long flags;
-
-        raw_spin_lock_irqsave(&ioapic_lock, flags);
-        for_each_irq_pin(entry, cfg->irq_2_pin) {
-                if (mpc_ioapic_ver(entry->apic) >= 0x20) {
-                        /*
-                         * Intr-remapping uses pin number as the virtual vector
-                         * in the RTE. Actual vector is programmed in
-                         * intr-remapping table entry. Hence for the io-apic
-                         * EOI we use the pin number.
-                         */
-                        if (irq_remapped(cfg))
-                                io_apic_eoi(entry->apic, entry->pin);
-                        else
-                                io_apic_eoi(entry->apic, cfg->vector);
-                } else {
-                        struct IO_APIC_route_entry rte, rte1;
-
-                        rte = rte1 =
-                                __ioapic_read_entry(entry->apic, entry->pin);
-
-                        /*
-                         * Mask the entry and change the trigger mode to edge.
-                         */
-                        rte1.mask = 1;
-                        rte1.trigger = IOAPIC_EDGE;
-
-                        __ioapic_write_entry(apic, pin, rte1);
-
-                        /*
-                         * Restore the previous level triggered entry.
-                         */
-                        __ioapic_write_entry(apic, pin, rte);
-                }
-        }
-        raw_spin_unlock_irqrestore(&ioapic_lock, flags);
-}
-
 static void ack_apic_level(struct irq_data *data)
 {
         struct irq_cfg *cfg = data->chip_data;