PCI/PCIe portdrv: Fix allocation of interrupts

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 the right 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() in the current code 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 if MSI-X are enabled, the right vectors will be
used for the right purposes.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Reviewed-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

1 files changed, 8 insertions, 4 deletions

diff --git a/include/linux/pcieport_if.h b/include/linux/pcieport_if.h
index a3832079508e..5d2afcfa6bc1 100644
--- a/include/linux/pcieport_if.h
+++ b/include/linux/pcieport_if.h
@@ -16,10 +16,14 @@
 #define PCIE_ANY_PORT                   7
 
 /* Service Type */
-#define PCIE_PORT_SERVICE_PME           1       /* Power Management Event */
-#define PCIE_PORT_SERVICE_AER           2       /* Advanced Error Reporting */
-#define PCIE_PORT_SERVICE_HP            4       /* Native Hotplug */
-#define PCIE_PORT_SERVICE_VC            8       /* Virtual Channel */
+#define PCIE_PORT_SERVICE_PME_SHIFT     0       /* Power Management Event */
+#define PCIE_PORT_SERVICE_PME           (1 << PCIE_PORT_SERVICE_PME_SHIFT)
+#define PCIE_PORT_SERVICE_AER_SHIFT     1       /* Advanced Error Reporting */
+#define PCIE_PORT_SERVICE_AER           (1 << PCIE_PORT_SERVICE_AER_SHIFT)
+#define PCIE_PORT_SERVICE_HP_SHIFT      2       /* Native Hotplug */
+#define PCIE_PORT_SERVICE_HP            (1 << PCIE_PORT_SERVICE_HP_SHIFT)
+#define PCIE_PORT_SERVICE_VC_SHIFT      3       /* Virtual Channel */
+#define PCIE_PORT_SERVICE_VC            (1 << PCIE_PORT_SERVICE_VC_SHIFT)
 
 /* Root/Upstream/Downstream Port's Interrupt Mode */
 #define PCIE_PORT_NO_IRQ                (-1)