ASMedia PCIe GPIO controllers connected to AMD SOC fail functional tests after returning from s2idle. This is because the BIOS checks whether the OSPM has called the _REG method to determine whether it can interact with the OperationRegion assigned to the device. To fix this issue, call acpi_evaluate_reg() when saving and restoring the state of PCI devices. Link: https://uefi.org/htmlspecs/ACPI_Spec_6_4_html/06_Device_Configuration/Device_Configuration.html#reg-region Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx> --- drivers/pci/pci.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index e38c2f6eebd4..071ecba548b0 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -1068,6 +1068,12 @@ static inline bool platform_pci_bridge_d3(struct pci_dev *dev) return acpi_pci_bridge_d3(dev); } +static inline int platform_toggle_reg(struct pci_dev *dev, int c) +{ + return acpi_evaluate_reg(ACPI_HANDLE(&dev->dev), + ACPI_ADR_SPACE_PCI_CONFIG, c); +} + /** * pci_update_current_state - Read power state of given device and cache it * @dev: PCI device to handle. @@ -1645,6 +1651,9 @@ static void pci_restore_ltr_state(struct pci_dev *dev) int pci_save_state(struct pci_dev *dev) { int i; + + platform_toggle_reg(dev, ACPI_REG_DISCONNECT); + /* XXX: 100% dword access ok here? */ for (i = 0; i < 16; i++) { pci_read_config_dword(dev, i * 4, &dev->saved_config_space[i]); @@ -1790,6 +1799,8 @@ void pci_restore_state(struct pci_dev *dev) pci_enable_acs(dev); pci_restore_iov_state(dev); + platform_toggle_reg(dev, ACPI_REG_CONNECT); + dev->state_saved = false; } EXPORT_SYMBOL(pci_restore_state); @@ -3203,6 +3214,7 @@ void pci_pm_init(struct pci_dev *dev) pci_read_config_word(dev, PCI_STATUS, &status); if (status & PCI_STATUS_IMM_READY) dev->imm_ready = 1; + platform_toggle_reg(dev, ACPI_REG_CONNECT); } static unsigned long pci_ea_flags(struct pci_dev *dev, u8 prop) -- 2.34.1
