6.1-stable review patch. If anyone has any objections, please let me know.
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From: Bjorn Helgaas bhelgaas@google.com
commit f93e71aea6c60ebff8adbd8941e678302d377869 upstream.
This reverts commit 08d0cc5f34265d1a1e3031f319f594bd1970976c.
Michael reported that when attempting to resume from suspend to RAM on ASUS mini PC PN51-BB757MDE1 (DMI model: MINIPC PN51-E1), 08d0cc5f3426 ("PCI/ASPM: Remove pcie_aspm_pm_state_change()") caused a 12-second delay with no output, followed by a reboot.
Workarounds include:
- Reverting 08d0cc5f3426 ("PCI/ASPM: Remove pcie_aspm_pm_state_change()") - Booting with "pcie_aspm=off" - Booting with "pcie_aspm.policy=performance" - "echo 0 | sudo tee /sys/bus/pci/devices/0000:03:00.0/link/l1_aspm" before suspending - Connecting a USB flash drive
Link: https://lore.kernel.org/r/20240102232550.1751655-1-helgaas@kernel.org Fixes: 08d0cc5f3426 ("PCI/ASPM: Remove pcie_aspm_pm_state_change()") Reported-by: Michael Schaller michael@5challer.de Link: https://lore.kernel.org/r/76c61361-b8b4-435f-a9f1-32b716763d62@5challer.de Signed-off-by: Bjorn Helgaas bhelgaas@google.com Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/pci/pci.c | 6 ++++++ drivers/pci/pci.h | 2 ++ drivers/pci/pcie/aspm.c | 19 +++++++++++++++++++ 3 files changed, 27 insertions(+)
--- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -1302,6 +1302,9 @@ static int pci_set_full_power_state(stru pci_restore_bars(dev); }
+ if (dev->bus->self) + pcie_aspm_pm_state_change(dev->bus->self); + return 0; }
@@ -1396,6 +1399,9 @@ static int pci_set_low_power_state(struc pci_power_name(dev->current_state), pci_power_name(state));
+ if (dev->bus->self) + pcie_aspm_pm_state_change(dev->bus->self); + return 0; }
--- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -561,10 +561,12 @@ bool pcie_wait_for_link(struct pci_dev * #ifdef CONFIG_PCIEASPM void pcie_aspm_init_link_state(struct pci_dev *pdev); void pcie_aspm_exit_link_state(struct pci_dev *pdev); +void pcie_aspm_pm_state_change(struct pci_dev *pdev); void pcie_aspm_powersave_config_link(struct pci_dev *pdev); #else static inline void pcie_aspm_init_link_state(struct pci_dev *pdev) { } static inline void pcie_aspm_exit_link_state(struct pci_dev *pdev) { } +static inline void pcie_aspm_pm_state_change(struct pci_dev *pdev) { } static inline void pcie_aspm_powersave_config_link(struct pci_dev *pdev) { } #endif
--- a/drivers/pci/pcie/aspm.c +++ b/drivers/pci/pcie/aspm.c @@ -1055,6 +1055,25 @@ void pcie_aspm_exit_link_state(struct pc up_read(&pci_bus_sem); }
+/* @pdev: the root port or switch downstream port */ +void pcie_aspm_pm_state_change(struct pci_dev *pdev) +{ + struct pcie_link_state *link = pdev->link_state; + + if (aspm_disabled || !link) + return; + /* + * Devices changed PM state, we should recheck if latency + * meets all functions' requirement + */ + down_read(&pci_bus_sem); + mutex_lock(&aspm_lock); + pcie_update_aspm_capable(link->root); + pcie_config_aspm_path(link); + mutex_unlock(&aspm_lock); + up_read(&pci_bus_sem); +} + void pcie_aspm_powersave_config_link(struct pci_dev *pdev) { struct pcie_link_state *link = pdev->link_state;