Since commit f492edb40b54 ("PCI: vmd: Add quirk to configure PCIe ASPM
and LTR"), ASPM is configured for NVMe devices enabled in VMD domain.
However, that doesn't cover the case when FADT has ACPI_FADT_NO_ASPM
set.
So add a new attribute to bypass aspm_disabled so OS can configure ASPM.
Fixes: f492edb40b54 ("PCI: vmd: Add quirk to configure PCIe ASPM and LTR")
Link: https://lore.kernel.org/linux-pm/218aa81f-9c6-5929-578d-8dc15f83dd48@xxxxxxxxx/
Signed-off-by: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx>
---
drivers/pci/pcie/aspm.c | 8 ++++++--
include/linux/pci.h | 1 +
2 files changed, 7 insertions(+), 2 deletions(-)
diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
index cee2365e54b8..e719605857b1 100644
--- a/drivers/pci/pcie/aspm.c
+++ b/drivers/pci/pcie/aspm.c
@@ -1416,8 +1416,12 @@ static int __pci_enable_link_state(struct pci_dev *pdev, int state, bool locked)
* the _OSC method), we can't honor that request.
*/
if (aspm_disabled) {
- pci_warn(pdev, "can't override BIOS ASPM; OS doesn't have ASPM control\n");
- return -EPERM;
+ if (aspm_support_enabled && pdev->aspm_os_control)
+ pci_info(pdev, "BIOS can't program ASPM, let OS control it\n");
+ else {
+ pci_warn(pdev, "can't override BIOS ASPM; OS doesn't have ASPM control\n");
+ return -EPERM;
+ }
}
if (!locked)
diff --git a/include/linux/pci.h b/include/linux/pci.h
index fb004fd4e889..58cbd4bea320 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -467,6 +467,7 @@ struct pci_dev {
unsigned int no_command_memory:1; /* No PCI_COMMAND_MEMORY */
unsigned int rom_bar_overlap:1; /* ROM BAR disable broken */
unsigned int rom_attr_enabled:1; /* Display of ROM attribute enabled? */
+ unsigned int aspm_os_control:1; /* Display of ROM attribute enabled? */
pci_dev_flags_t dev_flags;
atomic_t enable_cnt; /* pci_enable_device has been called */
--
2.43.0
