VMD does not support INTx for devices downstream from a VMD endpoint.
So initialize the PCI_INTERRUPT_LINE to 0 for all NVMe devices under
VMD to ensure other applications don't try to set up an INTx for them.
Signed-off-by: Nirmal Patel <nirmal.patel@xxxxxxxxxxxxxxx>
---
v2->v1: Change the execution from fixup.c to vmd.c
---
drivers/pci/controller/vmd.c | 13 +++++++++++++
1 file changed, 13 insertions(+)
diff --git a/drivers/pci/controller/vmd.c b/drivers/pci/controller/vmd.c
index a726de0af011..2e9b99969b81 100644
--- a/drivers/pci/controller/vmd.c
+++ b/drivers/pci/controller/vmd.c
@@ -778,6 +778,18 @@ static int vmd_pm_enable_quirk(struct pci_dev *pdev, void *userdata)
return 0;
}
+/*
+ * Some applications like SPDK reads PCI_INTERRUPT_LINE to decide
+ * whether INTx is enabled or not. Since VMD doesn't support INTx,
+ * write 0 to all NVMe devices under VMD.
+ */
+static int vmd_clr_int_line_reg(struct pci_dev *dev, void *userdata)
+{
+ if(dev->class == PCI_CLASS_STORAGE_EXPRESS)
+ pci_write_config_byte(dev, PCI_INTERRUPT_LINE, 0);
+ return 0;
+}
+
static int vmd_enable_domain(struct vmd_dev *vmd, unsigned long features)
{
struct pci_sysdata *sd = &vmd->sysdata;
@@ -932,6 +944,7 @@ static int vmd_enable_domain(struct vmd_dev *vmd, unsigned long features)
pci_scan_child_bus(vmd->bus);
vmd_domain_reset(vmd);
+ pci_walk_bus(vmd->bus, vmd_clr_int_line_reg, &features);
/* When Intel VMD is enabled, the OS does not discover the Root Ports
* owned by Intel VMD within the MMCFG space. pci_reset_bus() applies
--
2.39.1
