[PATCH 6.4 436/800] PCI: vmd: Reset VMD config register between soft reboots

Greg Kroah-Hartman
2023-07-16T20:13:15Z

From: Nirmal Patel <nirmal.patel@linux.intel.com>

[ Upstream commit b61cf04c49c3dfa70a0d6725d3eb40bf9b35cf71 ]

VMD driver can disable or enable MSI remapping by changing
VMCONFIG_MSI_REMAP register. This register needs to be set to the
default value during soft reboots. Drives failed to enumerate
when Windows boots after performing a soft reboot from Linux.
Windows doesn't support MSI remapping disable feature and stale
register value hinders Windows VMD driver initialization process.
Adding vmd_shutdown function to make sure to set the VMCONFIG
register to the default value.

Link: https://lore.kernel.org/r/20230224202811.644370-1-nirmal.patel@linux.intel.com
Fixes: ee81ee84f873 ("PCI: vmd: Disable MSI-X remapping when possible")
Signed-off-by: Nirmal Patel <nirmal.patel@linux.intel.com>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Reviewed-by: Jon Derrick <jonathan.derrick@linux.dev>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/pci/controller/vmd.c | 8 ++++++++
1 file changed, 8 insertions(+)

diff --git a/drivers/pci/controller/vmd.c b/drivers/pci/controller/vmd.c
index 990630ec57c6a..30ec18283aaf4 100644
--- a/drivers/pci/controller/vmd.c
+++ b/drivers/pci/controller/vmd.c
@@ -1036,6 +1036,13 @@ static void vmd_remove(struct pci_dev *dev)
ida_simple_remove(&vmd_instance_ida, vmd->instance);
}

+static void vmd_shutdown(struct pci_dev *dev)
+{
+ struct vmd_dev *vmd = pci_get_drvdata(dev);
+
+ vmd_remove_irq_domain(vmd);
+}
+
#ifdef CONFIG_PM_SLEEP
static int vmd_suspend(struct device *dev)
{
@@ -1101,6 +1108,7 @@ static struct pci_driver vmd_drv = {
.id_table = vmd_ids,
.probe = vmd_probe,
.remove = vmd_remove,
+ .shutdown = vmd_shutdown,
.driver = {
.pm = &vmd_dev_pm_ops,
},
--
2.39.2