From d899aa668498c07ff217b666ae9712990306e682 Mon Sep 17 00:00:00 2001
From: Nirmal Patel <nirmal.patel@linux.intel.com>
Date: Wed, 9 Nov 2022 07:26:52 -0700
Subject: [PATCH] PCI: vmd: Disable MSI remapping after suspend
Git-commit: d899aa668498c07ff217b666ae9712990306e682
Patch-mainline: v6.2-rc1
References: git-fixes

MSI remapping is disabled by VMD driver for Intel's Icelake and
newer systems in order to improve performance by setting
VMCONFIG_MSI_REMAP. By design VMCONFIG_MSI_REMAP register is cleared
by firmware during boot. The same register gets cleared when system
is put in S3 power state. VMD driver needs to set this register again
in order to avoid interrupt issues with devices behind VMD if MSI
remapping was disabled before.

Link: https://lore.kernel.org/r/20221109142652.450998-1-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: Francisco Munoz <francisco.munoz.ruiz@linux.intel.com>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/pci/controller/vmd.c |    5 +++++
 1 file changed, 5 insertions(+)

--- a/drivers/pci/controller/vmd.c
+++ b/drivers/pci/controller/vmd.c
@@ -848,6 +848,11 @@ static int vmd_resume(struct device *dev
 	struct vmd_dev *vmd = pci_get_drvdata(pdev);
 	int err, i;
 
+       if (vmd->irq_domain)
+               vmd_set_msi_remapping(vmd, true);
+       else
+               vmd_set_msi_remapping(vmd, false);
+
 	for (i = 0; i < vmd->msix_count; i++) {
 		err = devm_request_irq(dev, pci_irq_vector(pdev, i),
 				       vmd_irq, IRQF_NO_THREAD,