[PATCH] genirq: msi: refactor the msi_ops
The current msi_ops are short sighted in a number of ways, this patch attempts
to fix the glaring deficiences.
- Report in msi_ops if a 64bit address is needed in the msi message, so we
can fail 32bit only msi structures.
- Send and receive a full struct msi_msg in both setup and target. This is
a little cleaner and allows for architectures that need to modify the data
to retarget the msi interrupt to a different cpu.
- In target pass in the full cpu mask instead of just the first cpu in case
we can make use of the full cpu mask.
- Operate in terms of irqs and not vectors, currently there is still a 1-1
relationship but on architectures other than ia64 I expect this will change.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rajesh Shah <rajesh.shah@intel.com>
Cc: Andi Kleen <ak@muc.de>
Cc: "Protasevich, Natalie" <Natalie.Protasevich@UNISYS.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/include/linux/pci.h b/include/linux/pci.h
index b9bb6c4..2aabe90 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -617,6 +617,68 @@
struct msix_entry *entries, int nvec);
extern void pci_disable_msix(struct pci_dev *dev);
extern void msi_remove_pci_irq_vectors(struct pci_dev *dev);
+
+/*
+ * MSI operation vector. Used by the msi core code (drivers/pci/msi.c)
+ * to abstract platform-specific tasks relating to MSI address generation
+ * and resource management.
+ */
+struct msi_ops {
+ int needs_64bit_address;
+ /**
+ * setup - generate an MSI bus address and data for a given vector
+ * @pdev: PCI device context (in)
+ * @irq: irq allocated by the msi core (in)
+ * @msg: PCI bus address and data for msi message (out)
+ *
+ * Description: The setup op is used to generate a PCI bus addres and
+ * data which the msi core will program into the card MSI capability
+ * registers. The setup routine is responsible for picking an initial
+ * cpu to target the MSI at. The setup routine is responsible for
+ * examining pdev to determine the MSI capabilities of the card and
+ * generating a suitable address/data. The setup routine is
+ * responsible for allocating and tracking any system resources it
+ * needs to route the MSI to the cpu it picks, and for associating
+ * those resources with the passed in vector.
+ *
+ * Returns 0 if the MSI address/data was successfully setup.
+ **/
+
+ int (*setup) (struct pci_dev *pdev, unsigned int irq,
+ struct msi_msg *msg);
+
+ /**
+ * teardown - release resources allocated by setup
+ * @vector: vector context for resources (in)
+ *
+ * Description: The teardown op is used to release any resources
+ * that were allocated in the setup routine associated with the passed
+ * in vector.
+ **/
+
+ void (*teardown) (unsigned int irq);
+
+ /**
+ * target - retarget an MSI at a different cpu
+ * @vector: vector context for resources (in)
+ * @cpu: new cpu to direct vector at (in)
+ * @addr_hi: new value of PCI bus upper 32 bits (in/out)
+ * @addr_lo: new value of PCI bus lower 32 bits (in/out)
+ *
+ * Description: The target op is used to redirect an MSI vector
+ * at a different cpu. addr_hi/addr_lo coming in are the existing
+ * values that the MSI core has programmed into the card. The
+ * target code is responsible for freeing any resources (if any)
+ * associated with the old address, and generating a new PCI bus
+ * addr_hi/addr_lo that will redirect the vector at the indicated cpu.
+ **/
+
+ void (*target) (unsigned int irq, cpumask_t cpumask,
+ struct msi_msg *msg);
+};
+
+extern int msi_register(struct msi_ops *ops);
+
#endif
extern void pci_block_user_cfg_access(struct pci_dev *dev);