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Diffstat (limited to 'arch/i386/kernel/io_apic.c')
-rw-r--r--arch/i386/kernel/io_apic.c96
1 files changed, 78 insertions, 18 deletions
diff --git a/arch/i386/kernel/io_apic.c b/arch/i386/kernel/io_apic.c
index 350192d6ab9..3b7a63e0ed1 100644
--- a/arch/i386/kernel/io_apic.c
+++ b/arch/i386/kernel/io_apic.c
@@ -91,6 +91,46 @@ static struct irq_pin_list {
int apic, pin, next;
} irq_2_pin[PIN_MAP_SIZE];
+struct io_apic {
+ unsigned int index;
+ unsigned int unused[3];
+ unsigned int data;
+};
+
+static __attribute_const__ struct io_apic __iomem *io_apic_base(int idx)
+{
+ return (void __iomem *) __fix_to_virt(FIX_IO_APIC_BASE_0 + idx)
+ + (mp_ioapics[idx].mpc_apicaddr & ~PAGE_MASK);
+}
+
+static inline unsigned int io_apic_read(unsigned int apic, unsigned int reg)
+{
+ struct io_apic __iomem *io_apic = io_apic_base(apic);
+ writel(reg, &io_apic->index);
+ return readl(&io_apic->data);
+}
+
+static inline void io_apic_write(unsigned int apic, unsigned int reg, unsigned int value)
+{
+ struct io_apic __iomem *io_apic = io_apic_base(apic);
+ writel(reg, &io_apic->index);
+ writel(value, &io_apic->data);
+}
+
+/*
+ * Re-write a value: to be used for read-modify-write
+ * cycles where the read already set up the index register.
+ *
+ * Older SiS APIC requires we rewrite the index register
+ */
+static inline void io_apic_modify(unsigned int apic, unsigned int reg, unsigned int value)
+{
+ volatile struct io_apic *io_apic = io_apic_base(apic);
+ if (sis_apic_bug)
+ writel(reg, &io_apic->index);
+ writel(value, &io_apic->data);
+}
+
union entry_union {
struct { u32 w1, w2; };
struct IO_APIC_route_entry entry;
@@ -107,12 +147,34 @@ static struct IO_APIC_route_entry ioapic_read_entry(int apic, int pin)
return eu.entry;
}
+/*
+ * When we write a new IO APIC routing entry, we need to write the high
+ * word first! If the mask bit in the low word is clear, we will enable
+ * the interrupt, and we need to make sure the entry is fully populated
+ * before that happens.
+ */
static void ioapic_write_entry(int apic, int pin, struct IO_APIC_route_entry e)
{
unsigned long flags;
union entry_union eu;
eu.entry = e;
spin_lock_irqsave(&ioapic_lock, flags);
+ io_apic_write(apic, 0x11 + 2*pin, eu.w2);
+ io_apic_write(apic, 0x10 + 2*pin, eu.w1);
+ spin_unlock_irqrestore(&ioapic_lock, flags);
+}
+
+/*
+ * When we mask an IO APIC routing entry, we need to write the low
+ * word first, in order to set the mask bit before we change the
+ * high bits!
+ */
+static void ioapic_mask_entry(int apic, int pin)
+{
+ unsigned long flags;
+ union entry_union eu = { .entry.mask = 1 };
+
+ spin_lock_irqsave(&ioapic_lock, flags);
io_apic_write(apic, 0x10 + 2*pin, eu.w1);
io_apic_write(apic, 0x11 + 2*pin, eu.w2);
spin_unlock_irqrestore(&ioapic_lock, flags);
@@ -234,9 +296,7 @@ static void clear_IO_APIC_pin(unsigned int apic, unsigned int pin)
/*
* Disable it in the IO-APIC irq-routing table:
*/
- memset(&entry, 0, sizeof(entry));
- entry.mask = 1;
- ioapic_write_entry(apic, pin, entry);
+ ioapic_mask_entry(apic, pin);
}
static void clear_IO_APIC (void)
@@ -1227,9 +1287,11 @@ static void ioapic_register_intr(int irq, int vector, unsigned long trigger)
trigger == IOAPIC_LEVEL)
set_irq_chip_and_handler_name(irq, &ioapic_chip,
handle_fasteoi_irq, "fasteoi");
- else
+ else {
+ irq_desc[irq].status |= IRQ_DELAYED_DISABLE;
set_irq_chip_and_handler_name(irq, &ioapic_chip,
handle_edge_irq, "edge");
+ }
set_intr_gate(vector, interrupt[irq]);
}
@@ -2564,18 +2626,16 @@ void arch_teardown_msi_irq(unsigned int irq)
static void target_ht_irq(unsigned int irq, unsigned int dest)
{
- u32 low, high;
- low = read_ht_irq_low(irq);
- high = read_ht_irq_high(irq);
+ struct ht_irq_msg msg;
+ fetch_ht_irq_msg(irq, &msg);
- low &= ~(HT_IRQ_LOW_DEST_ID_MASK);
- high &= ~(HT_IRQ_HIGH_DEST_ID_MASK);
+ msg.address_lo &= ~(HT_IRQ_LOW_DEST_ID_MASK);
+ msg.address_hi &= ~(HT_IRQ_HIGH_DEST_ID_MASK);
- low |= HT_IRQ_LOW_DEST_ID(dest);
- high |= HT_IRQ_HIGH_DEST_ID(dest);
+ msg.address_lo |= HT_IRQ_LOW_DEST_ID(dest);
+ msg.address_hi |= HT_IRQ_HIGH_DEST_ID(dest);
- write_ht_irq_low(irq, low);
- write_ht_irq_high(irq, high);
+ write_ht_irq_msg(irq, &msg);
}
static void set_ht_irq_affinity(unsigned int irq, cpumask_t mask)
@@ -2613,7 +2673,7 @@ int arch_setup_ht_irq(unsigned int irq, struct pci_dev *dev)
vector = assign_irq_vector(irq);
if (vector >= 0) {
- u32 low, high;
+ struct ht_irq_msg msg;
unsigned dest;
cpumask_t tmp;
@@ -2621,9 +2681,10 @@ int arch_setup_ht_irq(unsigned int irq, struct pci_dev *dev)
cpu_set(vector >> 8, tmp);
dest = cpu_mask_to_apicid(tmp);
- high = HT_IRQ_HIGH_DEST_ID(dest);
+ msg.address_hi = HT_IRQ_HIGH_DEST_ID(dest);
- low = HT_IRQ_LOW_BASE |
+ msg.address_lo =
+ HT_IRQ_LOW_BASE |
HT_IRQ_LOW_DEST_ID(dest) |
HT_IRQ_LOW_VECTOR(vector) |
((INT_DEST_MODE == 0) ?
@@ -2635,8 +2696,7 @@ int arch_setup_ht_irq(unsigned int irq, struct pci_dev *dev)
HT_IRQ_LOW_MT_ARBITRATED) |
HT_IRQ_LOW_IRQ_MASKED;
- write_ht_irq_low(irq, low);
- write_ht_irq_high(irq, high);
+ write_ht_irq_msg(irq, &msg);
set_irq_chip_and_handler_name(irq, &ht_irq_chip,
handle_edge_irq, "edge");