From: Gabriele Paoloni <gabriele.paoloni@huawei.com>
Date: Tue, 23 May 2017 15:23:59 +0100
Subject: PCI/portdrv: Allocate MSI/MSI-X vector for Downstream Port
Containment
Git-commit: ae6dc7deac2a8639595437af3df5fade878a1601
Patch-mainline: v4.13-rc1
References: fate#326249
Currently pcie_port_enable_irq_vec() only allocates MSI/MSI-X vectors for
PME, hotplug, and AER.
The Downstream Port Containment feature also supports MSI/MSI-X interrupts,
so allocate a vector for it, too.
Signed-off-by: Liudongdong <liudongdong3@huawei.com>
Signed-off-by: Gabriele Paoloni <gabriele.paoloni@huawei.com>
[bhelgaas: changelog, comment]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Matthias Brugger <mbrugger@suse.com>
---
drivers/pci/pcie/portdrv_core.c | 27 +++++++++++++++++++++++++++
1 file changed, 27 insertions(+)
diff --git a/drivers/pci/pcie/portdrv_core.c b/drivers/pci/pcie/portdrv_core.c
index e00b5da07fef..313a21df1692 100644
--- a/drivers/pci/pcie/portdrv_core.c
+++ b/drivers/pci/pcie/portdrv_core.c
@@ -123,6 +123,33 @@ static int pcie_port_enable_irq_vec(struct pci_dev *dev, int *irqs, int mask)
nvec = max(nvec, entry + 1);
}
+ if (mask & PCIE_PORT_SERVICE_DPC) {
+ u16 reg16, pos;
+
+ /*
+ * Per PCIe r4.0 (v0.9), sec 7.9.15.2, the DPC Interrupt
+ * Message Number in the DPC Capability register indicates
+ * which MSI/MSI-X vector is used for DPC.
+ *
+ * "For MSI, the [DPC Interrupt Message Number] indicates
+ * the offset between the base Message Data and the
+ * interrupt message that is generated."
+ *
+ * "For MSI-X, the [DPC Interrupt Message Number] indicates
+ * which MSI-X Table entry is used to generate the
+ * interrupt message."
+ */
+ pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_DPC);
+ pci_read_config_word(dev, pos + PCI_EXP_DPC_CAP, ®16);
+ entry = reg16 & 0x1f;
+ if (entry >= nr_entries)
+ goto out_free_irqs;
+
+ irqs[PCIE_PORT_SERVICE_DPC_SHIFT] = pci_irq_vector(dev, entry);
+
+ nvec = max(nvec, entry + 1);
+ }
+
/*
* If nvec is equal to the allocated number of entries, we can just use
* what we have. Otherwise, the port has some extra entries not for the
--
2.19.1