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PCI: Disable D3cold on Asus B1400 PCI-NVMe bridge

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The Asus B1400 with original shipped firmware versions and VMD disabled
cannot resume from suspend: the NVMe device becomes unresponsive and
inaccessible.

This appears to be an untested D3cold transition by the vendor; Intel
socwatch shows that Windows leaves the NVMe device and parent bridge in D0
during suspend, even though these firmware versions have StorageD3Enable=1.

The NVMe device and parent PCI bridge both share the same "PXP" ACPI power
resource, which gets turned off as both devices are put into D3cold during
suspend. The _OFF() method calls DL23() which sets a L23E bit at offset
0xe2 into the PCI configuration space for this root port.  This is the
specific write that the _ON() routine is unable to recover from. This
register is not documented in the public chipset datasheet.

Disallow D3cold on the PCI bridge to enable successful suspend/resume.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=215742
Link: https://lore.kernel.org/r/20240228075316.7404-1-drake@endlessos.org
Signed-off-by: Daniel Drake <drake@endlessos.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Jian-Hong Pan <jhp@endlessos.org>
Acked-by: Rafael J. Wysocki <rafael@kernel.org>
This commit is contained in:
Daniel Drake 2024-02-28 08:53:15 +01:00 committed by Bjorn Helgaas
parent 6613476e22
commit cdea98bf1f
1 changed files with 48 additions and 0 deletions
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48
arch/x86/pci/fixup.c
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@ -907,6 +907,54 @@ static void chromeos_fixup_apl_pci_l1ss_capability(struct pci_dev *dev)
DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, 0x5ad6, chromeos_save_apl_pci_l1ss_capability);
DECLARE_PCI_FIXUP_RESUME(PCI_VENDOR_ID_INTEL, 0x5ad6, chromeos_fixup_apl_pci_l1ss_capability);
/*
* Disable D3cold on Asus B1400 PCI-NVMe bridge
*
* On this platform with VMD off, the NVMe device cannot successfully power
* back on from D3cold. This appears to be an untested transition by the
* vendor: Windows leaves the NVMe and parent bridge in D0 during suspend.
*
* We disable D3cold on the parent bridge for simplicity, and the fact that
* both parent bridge and NVMe device share the same power resource.
*
* This is only needed on BIOS versions before 308; the newer versions flip
* StorageD3Enable from 1 to 0.
*/
static const struct dmi_system_id asus_nvme_broken_d3cold_table[] = {
{
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
DMI_MATCH(DMI_BIOS_VERSION, "B1400CEAE.304"),
},
},
{
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
DMI_MATCH(DMI_BIOS_VERSION, "B1400CEAE.305"),
},
},
{
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
DMI_MATCH(DMI_BIOS_VERSION, "B1400CEAE.306"),
},
},
{
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
DMI_MATCH(DMI_BIOS_VERSION, "B1400CEAE.307"),
},
},
{}
};
static void asus_disable_nvme_d3cold(struct pci_dev *pdev)
{
if (dmi_check_system(asus_nvme_broken_d3cold_table) > 0)
pci_d3cold_disable(pdev);
}
DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, 0x9a09, asus_disable_nvme_d3cold);
#ifdef CONFIG_SUSPEND
/*
* Root Ports on some AMD SoCs advertise PME_Support for D3hot and D3cold, but