PCI: vmd: Disable MSI remapping after suspend
authorNirmal Patel <nirmal.patel@linux.intel.com>
Wed, 9 Nov 2022 14:26:52 +0000 (07:26 -0700)
committerLorenzo Pieralisi <lpieralisi@kernel.org>
Fri, 11 Nov 2022 11:00:26 +0000 (12:00 +0100)
commitd899aa668498c07ff217b666ae9712990306e682
treee2349446c01961a716b02e733ec0412af6ebdf99
parent9abf2313adc1ca1b6180c508c25f22f9395cc780
PCI: vmd: Disable MSI remapping after suspend

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>
drivers/pci/controller/vmd.c