PCI MSI: Add support for multiple MSI
Add the new API pci_enable_msi_block() to allow drivers to
request multiple MSI and reimplement pci_enable_msi in terms of
pci_enable_msi_block. Ensure that the architecture back ends don't
have to know about multiple MSI.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
diff --git a/include/linux/msi.h b/include/linux/msi.h
index 37c1bbe..6991ab5 100644
--- a/include/linux/msi.h
+++ b/include/linux/msi.h
@@ -21,6 +21,7 @@
struct msi_desc {
struct {
__u8 is_msix : 1;
+ __u8 multiple: 3; /* log2 number of messages */
__u8 maskbit : 1; /* mask-pending bit supported ? */
__u8 is_64 : 1; /* Address size: 0=32bit 1=64bit */
__u8 pos; /* Location of the msi capability */
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 7baf2a5..1f6c5dd 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -789,7 +789,7 @@
#ifndef CONFIG_PCI_MSI
-static inline int pci_enable_msi(struct pci_dev *dev)
+static inline int pci_enable_msi_block(struct pci_dev *dev, unsigned int nvec)
{
return -1;
}
@@ -824,7 +824,7 @@
return 0;
}
#else
-extern int pci_enable_msi(struct pci_dev *dev);
+extern int pci_enable_msi_block(struct pci_dev *dev, unsigned int nvec);
extern void pci_msi_shutdown(struct pci_dev *dev);
extern void pci_disable_msi(struct pci_dev *dev);
extern int pci_msix_table_size(struct pci_dev *dev);
@@ -846,6 +846,8 @@
extern int pcie_aspm_enabled(void);
#endif
+#define pci_enable_msi(pdev) pci_enable_msi_block(pdev, 1)
+
#ifdef CONFIG_HT_IRQ
/* The functions a driver should call */
int ht_create_irq(struct pci_dev *dev, int idx);