From cdea98bf1faef23166262825ce44648be6ebff42 Mon Sep 17 00:00:00 2001 From: Daniel Drake Date: Wed, 28 Feb 2024 08:53:15 +0100 Subject: [PATCH] PCI: Disable D3cold on Asus B1400 PCI-NVMe bridge 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 Signed-off-by: Bjorn Helgaas Acked-by: Jian-Hong Pan Acked-by: Rafael J. Wysocki --- arch/x86/pci/fixup.c | 48 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 48 insertions(+) diff --git a/arch/x86/pci/fixup.c b/arch/x86/pci/fixup.c index f347c20247d3..b33afb240601 100644 --- a/arch/x86/pci/fixup.c +++ b/arch/x86/pci/fixup.c @@ -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