#include <linux/irq.h>
#include <linux/interrupt.h>
#include <linux/init.h>
-#include <linux/config.h>
#include <linux/ioport.h>
#include <linux/smp_lock.h>
#include <linux/pci.h>
static void msi_cache_ctor(void *p, kmem_cache_t *cache, unsigned long flags)
{
- memset(p, 0, NR_IRQS * sizeof(struct msi_desc));
+ memset(p, 0, sizeof(struct msi_desc));
}
static int msi_cache_init(void)
{
msi_cachep = kmem_cache_create("msi_cache",
- NR_IRQS * sizeof(struct msi_desc),
+ sizeof(struct msi_desc),
0, SLAB_HWCACHE_ALIGN, msi_cache_ctor, NULL);
if (!msi_cachep)
return -ENOMEM;
return 0;
}
+/**
+ * pci_msi_supported - check whether MSI may be enabled on device
+ * @dev: pointer to the pci_dev data structure of MSI device function
+ *
+ * MSI must be globally enabled and supported by the device and its root
+ * bus. But, the root bus is not easy to find since some architectures
+ * have virtual busses on top of the PCI hierarchy (for instance the
+ * hypertransport bus), while the actual bus where MSI must be supported
+ * is below. So we test the MSI flag on all parent busses and assume
+ * that no quirk will ever set the NO_MSI flag on a non-root bus.
+ **/
+static
+int pci_msi_supported(struct pci_dev * dev)
+{
+ struct pci_bus *bus;
+
+ if (!pci_msi_enable || !dev || dev->no_msi)
+ return -EINVAL;
+
+ /* check MSI flags of all parent busses */
+ for (bus = dev->bus; bus; bus = bus->parent)
+ if (bus->bus_flags & PCI_BUS_FLAGS_NO_MSI)
+ return -EINVAL;
+
+ return 0;
+}
+
/**
* pci_enable_msi - configure device's MSI capability structure
* @dev: pointer to the pci_dev data structure of MSI device function
**/
int pci_enable_msi(struct pci_dev* dev)
{
- struct pci_bus *bus;
- int pos, temp, status = -EINVAL;
+ int pos, temp, status;
u16 control;
- if (!pci_msi_enable || !dev)
- return status;
-
- if (dev->no_msi)
- return status;
-
- for (bus = dev->bus; bus; bus = bus->parent)
- if (bus->bus_flags & PCI_BUS_FLAGS_NO_MSI)
- return -EINVAL;
+ if (pci_msi_supported(dev) < 0)
+ return -EINVAL;
temp = dev->irq;
**/
int pci_enable_msix(struct pci_dev* dev, struct msix_entry *entries, int nvec)
{
- struct pci_bus *bus;
int status, pos, nr_entries, free_vectors;
int i, j, temp;
u16 control;
unsigned long flags;
- if (!pci_msi_enable || !dev || !entries)
+ if (!entries || pci_msi_supported(dev) < 0)
return -EINVAL;
- if (dev->no_msi)
- return -EINVAL;
-
- for (bus = dev->bus; bus; bus = bus->parent)
- if (bus->bus_flags & PCI_BUS_FLAGS_NO_MSI)
- return -EINVAL;
-
status = msi_init();
if (status < 0)
return status;