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| author | Jian-Hong Pan <jhp@endlessos.org> | 2024-10-01 11:34:40 +0300 |
|---|---|---|
| committer | Krzysztof Wilczyński <kwilczynski@kernel.org> | 2024-11-07 00:16:26 +0300 |
| commit | e1714f3b1f4d2af5df26e4a0e4a70ef64b15e3ee (patch) | |
| tree | 9ef152f714cf036b905e7f3de8e6b3cf2812d87c /drivers/pci/pcie | |
| parent | 7447990137bf06b2aeecad9c6081e01a9f47f2aa (diff) | |
| download | linux-e1714f3b1f4d2af5df26e4a0e4a70ef64b15e3ee.tar.xz | |
PCI/ASPM: Add notes about enabling PCI-PM L1SS to pci_enable_link_state(_locked)
According to "PCIe r6.0, sec 5.5.4", add note about D0 requirement in
pci_enable_link_state() kernel-doc.
Link: https://lore.kernel.org/r/20241001083438.10070-6-jhp@endlessos.org
Signed-off-by: Jian-Hong Pan <jhp@endlessos.org>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Diffstat (limited to 'drivers/pci/pcie')
| -rw-r--r-- | drivers/pci/pcie/aspm.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c index e943691bc931..28567d457613 100644 --- a/drivers/pci/pcie/aspm.c +++ b/drivers/pci/pcie/aspm.c @@ -1450,6 +1450,9 @@ static int __pci_enable_link_state(struct pci_dev *pdev, int state, bool locked) * touch the LNKCTL register. Also note that this does not enable states * disabled by pci_disable_link_state(). Return 0 or a negative errno. * + * Note: Ensure devices are in D0 before enabling PCI-PM L1 PM Substates, per + * PCIe r6.0, sec 5.5.4. + * * @pdev: PCI device * @state: Mask of ASPM link states to enable */ @@ -1466,6 +1469,9 @@ EXPORT_SYMBOL(pci_enable_link_state); * can't touch the LNKCTL register. Also note that this does not enable states * disabled by pci_disable_link_state(). Return 0 or a negative errno. * + * Note: Ensure devices are in D0 before enabling PCI-PM L1 PM Substates, per + * PCIe r6.0, sec 5.5.4. + * * @pdev: PCI device * @state: Mask of ASPM link states to enable * |