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authorLinus Torvalds <torvalds@merom.osdl.org>2006-11-08 10:23:03 -0800
committerLinus Torvalds <torvalds@merom.osdl.org>2006-11-08 10:23:03 -0800
commit6c0ffb9d2fd987c79c6cbb81c3f3011c63749b1a (patch)
treeae135f5fcc6ab29f3fc0d057f4a9c10e5be58cbf /arch
parent464908d7e2a9f77cb50ee905cda8a59e5b4e50e4 (diff)
x86-64: clean up io-apic accesses
This is just commit 130fe05dbc0114609cfef9815c0c5580b42decfa ported to x86-64, for all the same reasons. It cleans up the IO-APIC accesses in order to then fix the ordering issues. We move the accessor functions (that were only used by io_apic.c) out of a header file, and use proper memory-mapped accesses rather than making up our own "volatile" pointers. Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'arch')
-rw-r--r--arch/x86_64/kernel/io_apic.c46
1 files changed, 46 insertions, 0 deletions
diff --git a/arch/x86_64/kernel/io_apic.c b/arch/x86_64/kernel/io_apic.c
index fe429e5d6b2..96e02d84571 100644
--- a/arch/x86_64/kernel/io_apic.c
+++ b/arch/x86_64/kernel/io_apic.c
@@ -88,6 +88,52 @@ static struct irq_pin_list {
short 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.
+ */
+static inline void io_apic_modify(unsigned int apic, unsigned int value)
+{
+ struct io_apic __iomem *io_apic = io_apic_base(apic);
+ writel(value, &io_apic->data);
+}
+
+/*
+ * Synchronize the IO-APIC and the CPU by doing
+ * a dummy read from the IO-APIC
+ */
+static inline void io_apic_sync(unsigned int apic)
+{
+ struct io_apic __iomem *io_apic = io_apic_base(apic);
+ readl(&io_apic->data);
+}
+
#define __DO_ACTION(R, ACTION, FINAL) \
\
{ \