diff options
| author |   Mika Westerberg <mika.westerberg@linux.intel.com> | 2019-08-07 13:57:18 +0300 |
|---|---|---|
| committer |   Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2019-08-07 13:06:42 +0200 |
| commit | 0617bdede5114a0002298b12cd0ca2b0cfd0395d (patch) | |
| tree | 11a76457d1711325d562793da8ffebe48d65c7bb /drivers/pci/pci.c | |
| parent | Linux 5.3-rc3 (diff) | |
| download | linux-dev-0617bdede5114a0002298b12cd0ca2b0cfd0395d.tar.xz linux-dev-0617bdede5114a0002298b12cd0ca2b0cfd0395d.zip | |
Revert "PCI: Add missing link delays required by the PCIe spec"
Commit c2bf1fc212f7 ("PCI: Add missing link delays required by the PCIe
spec") turned out causing issues with some systems either by making them
unresponsive or slowing down runtime and system wide resume of PCIe
devices. While root cause for the unresponsiveness is still under
investigation given the amount of issues reported better to revert it
for now.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=204413
Link: https://lore.kernel.org/linux-pci/SL2P216MB01878BBCD75F21D882AEEA2880C60@SL2P216MB0187.KORP216.PROD.OUTLOOK.COM/
Link: https://lore.kernel.org/linux-pci/2857501d-c167-547d-c57d-d5d24ea1f1dc@molgen.mpg.de/
Reported-by: Matthias Andree <matthias.andree@gmx.de>
Reported-by: Paul Menzel <pmenzel@molgen.mpg.de>
Reported-by: Nicholas Johnson <nicholas.johnson-opensource@outlook.com.au>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/pci/pci.c')
| -rw-r--r-- | drivers/pci/pci.c | 29 |
1 files changed, 10 insertions, 19 deletions
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 29ed5ec1ac27..1b27b5af3d55 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -1025,10 +1025,15 @@ static void __pci_start_power_transition(struct pci_dev *dev, pci_power_t state) if (state == PCI_D0) { pci_platform_power_transition(dev, PCI_D0); /* - * Mandatory power management transition delays are - * handled in the PCIe portdrv resume hooks. + * Mandatory power management transition delays, see + * PCI Express Base Specification Revision 2.0 Section + * 6.6.1: Conventional Reset. Do not delay for + * devices powered on/off by corresponding bridge, + * because have already delayed for the bridge. */ if (dev->runtime_d3cold) { + if (dev->d3cold_delay && !dev->imm_ready) + msleep(dev->d3cold_delay); /* * When powering on a bridge from D3cold, the * whole hierarchy may be powered on into @@ -4602,16 +4607,14 @@ static int pci_pm_reset(struct pci_dev *dev, int probe) return pci_dev_wait(dev, "PM D3->D0", PCIE_RESET_READY_POLL_MS); } - /** - * pcie_wait_for_link_delay - Wait until link is active or inactive + * pcie_wait_for_link - Wait until link is active or inactive * @pdev: Bridge device * @active: waiting for active or inactive? - * @delay: Delay to wait after link has become active (in ms) * * Use this to wait till link becomes active or inactive. */ -bool pcie_wait_for_link_delay(struct pci_dev *pdev, bool active, int delay) +bool pcie_wait_for_link(struct pci_dev *pdev, bool active) { int timeout = 1000; bool ret; @@ -4648,25 +4651,13 @@ bool pcie_wait_for_link_delay(struct pci_dev *pdev, bool active, int delay) timeout -= 10; } if (active && ret) - msleep(delay); + msleep(100); else if (ret != active) pci_info(pdev, "Data Link Layer Link Active not %s in 1000 msec\n", active ? "set" : "cleared"); return ret == active; } -/** - * pcie_wait_for_link - Wait until link is active or inactive - * @pdev: Bridge device - * @active: waiting for active or inactive? - * - * Use this to wait till link becomes active or inactive. - */ -bool pcie_wait_for_link(struct pci_dev *pdev, bool active) -{ - return pcie_wait_for_link_delay(pdev, active, 100); -} - void pci_reset_secondary_bus(struct pci_dev *dev) { u16 ctrl; |