diff options
| author | Bjorn Helgaas <bhelgaas@google.com> | 2024-03-06 00:15:25 +0300 |
|---|---|---|
| committer | Bjorn Helgaas <bhelgaas@google.com> | 2024-03-12 20:09:11 +0300 |
| commit | 64dbb2d707444f691539fb12aacf81797786c10b (patch) | |
| tree | 1c8db6a59e1c466528413171717814af94fb862c /drivers/pci/pci.c | |
| parent | c198fafa0125e97728d16411aa653602900ab0bc (diff) | |
| download | linux-64dbb2d707444f691539fb12aacf81797786c10b.tar.xz | |
PCI/ASPM: Disable L1 before configuring L1 Substates
Per PCIe r6.1, sec 5.5.4, L1 must be disabled while setting ASPM L1 PM
Substates enable bits. Previously this was enforced by clearing
PCI_EXP_LNKCTL_ASPMC before calling pci_restore_aspm_l1ss_state().
Move the L1 (and L0s, although that doesn't seem required) disable into
pci_restore_aspm_l1ss_state() itself so it's closer to the code that
depends on it.
Link: https://lore.kernel.org/r/20240223213733.GA115410@bhelgaas
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Diffstat (limited to 'drivers/pci/pci.c')
| -rw-r--r-- | drivers/pci/pci.c | 16 |
1 files changed, 3 insertions, 13 deletions
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 4ea98665172d..5a4b501a3f41 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -1633,13 +1633,14 @@ static void pci_restore_pcie_state(struct pci_dev *dev) { int i = 0; struct pci_cap_saved_state *save_state; - u16 *cap, lnkctl; + u16 *cap; /* * Restore max latencies (in the LTR capability) before enabling * LTR itself in PCI_EXP_DEVCTL2. */ pci_restore_ltr_state(dev); + pci_restore_aspm_l1ss_state(dev); save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP); if (!save_state) @@ -1654,23 +1655,12 @@ static void pci_restore_pcie_state(struct pci_dev *dev) cap = (u16 *)&save_state->cap.data[0]; pcie_capability_write_word(dev, PCI_EXP_DEVCTL, cap[i++]); - - /* Restore LNKCTL register with ASPM control field clear */ - lnkctl = cap[i++]; - pcie_capability_write_word(dev, PCI_EXP_LNKCTL, - lnkctl & ~PCI_EXP_LNKCTL_ASPMC); - + pcie_capability_write_word(dev, PCI_EXP_LNKCTL, cap[i++]); pcie_capability_write_word(dev, PCI_EXP_SLTCTL, cap[i++]); pcie_capability_write_word(dev, PCI_EXP_RTCTL, cap[i++]); pcie_capability_write_word(dev, PCI_EXP_DEVCTL2, cap[i++]); pcie_capability_write_word(dev, PCI_EXP_LNKCTL2, cap[i++]); pcie_capability_write_word(dev, PCI_EXP_SLTCTL2, cap[i++]); - - pci_restore_aspm_l1ss_state(dev); - - /* Restore ASPM control after restoring L1SS state */ - pcie_capability_set_word(dev, PCI_EXP_LNKCTL, - lnkctl & PCI_EXP_LNKCTL_ASPMC); } static int pci_save_pcix_state(struct pci_dev *dev) |