Now that we added a hook to be called from device_add, save the default values from the HW registers early in the boot for further reuse during hot device add/remove operations. If the link is down during boot, assume that we want to enable L0s and L1 following hotplug insertion as well as L1SS if supported. Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=194895 Signed-off-by: Sinan Kaya <okaya@xxxxxxxxxxxxxx> --- drivers/pci/pcie/aspm.c | 34 ++++++++++++++++++++++++++++++---- 1 file changed, 30 insertions(+), 4 deletions(-) diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c index e33f84b..c7da087 100644 --- a/drivers/pci/pcie/aspm.c +++ b/drivers/pci/pcie/aspm.c @@ -505,8 +505,10 @@ static void pcie_aspm_cap_init(struct pcie_link_state *link, int blacklist) */ if (dwreg.support & upreg.support & PCIE_LINK_STATE_L0S) link->aspm_support |= ASPM_STATE_L0S; - if (dwreg.enabled & PCIE_LINK_STATE_L0S) + if (dwreg.enabled & PCIE_LINK_STATE_L0S) { link->aspm_enabled |= ASPM_STATE_L0S_UP; + link->aspm_default |= ASPM_STATE_L0S_UP; + } if (upreg.enabled & PCIE_LINK_STATE_L0S) link->aspm_enabled |= ASPM_STATE_L0S_DW; link->latency_up.l0s = calc_l0s_latency(upreg.latency_encoding_l0s); @@ -542,9 +544,6 @@ static void pcie_aspm_cap_init(struct pcie_link_state *link, int blacklist) if (link->aspm_support & ASPM_STATE_L1SS) aspm_calc_l1ss_info(link, &upreg, &dwreg); - /* Save default state */ - link->aspm_default = link->aspm_enabled; - /* Setup initial capable state. Will be updated later */ link->aspm_capable = link->aspm_support; /* @@ -835,11 +834,38 @@ static int pci_aspm_init_downstream(struct pci_dev *pdev) static int pci_aspm_init_upstream(struct pci_dev *pdev) { struct pcie_link_state *link; + struct aspm_register_info upreg; + u16 lnk_status; + bool ret; link = alloc_pcie_link_state(pdev); if (!link) return -ENOMEM; + pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lnk_status); + ret = !!(lnk_status & PCI_EXP_LNKSTA_DLLLA); + + if (ret) { + pcie_get_aspm_reg(pdev, &upreg); + if (upreg.enabled & PCIE_LINK_STATE_L0S) + link->aspm_default |= ASPM_STATE_L0S_DW; + if (upreg.enabled & PCIE_LINK_STATE_L1) + link->aspm_default |= ASPM_STATE_L1; + if (upreg.l1ss_ctl1 & PCI_L1SS_CTL1_ASPM_L1_1) + link->aspm_default |= ASPM_STATE_L1_1; + if (upreg.l1ss_ctl1 & PCI_L1SS_CTL1_ASPM_L1_2) + link->aspm_default |= ASPM_STATE_L1_2; + if (upreg.l1ss_ctl1 & PCI_L1SS_CTL1_PCIPM_L1_1) + link->aspm_default |= ASPM_STATE_L1_1_PCIPM; + if (upreg.l1ss_ctl1 & PCI_L1SS_CTL1_PCIPM_L1_2) + link->aspm_default |= ASPM_STATE_L1_2_PCIPM; + } else { + if (!pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_L1SS)) + link->aspm_default = ASPM_STATE_L0S | ASPM_STATE_L1; + else + link->aspm_default = ASPM_STATE_ALL; + } + return 0; } -- 1.9.1
