Rafael J. Wysocki wrote: > From: Rafael J. Wysocki <rjw@xxxxxxx> > > If MSI-X interrupt mode is used by the PCI Express port driver, too > many vectors are allocated and it is not ensured that the right > vectors will be used for various services. Namely, the PCI Express > specification states that both PCI Express native PME and PCI Express > hotplug will always use the same MSI or MSI-X message for signalling > interrupts, which implies that the same vector will be used by both > of them. Also, the VC service does not use interrupts at all. > Moreover, is not clear which of the vectors allocated by > pci_enable_msix() will be used for PME and hotplug and which of them > will be used for AER if all of these services are configured. > > For these reasons, rework the allocation of interrupts for PCI > Express ports so that at most two vectors are allocated and ensure > that the right vector will be used for the right purpose. > > Signed-off-by: Rafael J. Wysocki <rjw@xxxxxxx> > --- > drivers/pci/pcie/portdrv.h | 1 > drivers/pci/pcie/portdrv_core.c | 155 +++++++++++++++++++++++++++++----------- > 2 files changed, 117 insertions(+), 39 deletions(-) > > Index: linux-2.6/drivers/pci/pcie/portdrv.h > =================================================================== > --- linux-2.6.orig/drivers/pci/pcie/portdrv.h > +++ linux-2.6/drivers/pci/pcie/portdrv.h > @@ -25,6 +25,7 @@ > #define PCIE_CAPABILITIES_REG 0x2 > #define PCIE_SLOT_CAPABILITIES_REG 0x14 > #define PCIE_PORT_DEVICE_MAXSERVICES 4 > +#define PORT_MSI_VECTOR_MASK 0x1f > > #define get_descriptor_id(type, service) (((type - 4) << 4) | service) > > Index: linux-2.6/drivers/pci/pcie/portdrv_core.c > =================================================================== > --- linux-2.6.orig/drivers/pci/pcie/portdrv_core.c > +++ linux-2.6/drivers/pci/pcie/portdrv_core.c > @@ -30,55 +30,120 @@ static void release_pcie_device(struct d > } > > /** > + * fix_up_vectors - ensure the right ordering of MSI-X interrupt vectors > + * @dev: PCI Express port that is going to use the vectors > + * @vectors: Array of interrupt vectors to check (2 entries) > + * > + * Return value: > + * 0 on success, error code if the values read from config registers are not as > + * expected > + * > + * If this function is called, we are going to use two interrupt vectors which > + * may be different, but we have to make sure they are in the right order such > + * that the vector to be used for PME and hotplug signalling is the first one. > + * > + * NOTE: The assumption here is that MSI message offset (with respect to the > + * base Message Data) equal to N corresponds to index N in the array of vectors > + * returned by pci_enable_msix(). > + */ I've posted the similar patch recently, which doesn't have this assumption. Please take a look. http://marc.info/?l=linux-pci&m=122992792507715&w=2 NOTE: I've confirmed MSI and INTx still work with my patch, but it is not tested on the machine with MSI-X capable port, since I don't have such environment. Thanks, Kenji Kaneshige -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
