diff options
Diffstat (limited to 'drivers/pci')
-rw-r--r-- | drivers/pci/pcie/aspm.c | 93 |
1 files changed, 42 insertions, 51 deletions
diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c index 71296ee59581..a96b7424c9bc 100644 --- a/drivers/pci/pcie/aspm.c +++ b/drivers/pci/pcie/aspm.c @@ -41,11 +41,6 @@ #define ASPM_STATE_ALL (ASPM_STATE_L0S | ASPM_STATE_L1 | \ ASPM_STATE_L1SS) -struct aspm_latency { - u32 l0s; /* L0s latency (nsec) */ - u32 l1; /* L1 latency (nsec) */ -}; - struct pcie_link_state { struct pci_dev *pdev; /* Upstream component of the Link */ struct pci_dev *downstream; /* Downstream component, function 0 */ @@ -65,15 +60,6 @@ struct pcie_link_state { u32 clkpm_enabled:1; /* Current Clock PM state */ u32 clkpm_default:1; /* Default Clock PM state by BIOS */ u32 clkpm_disable:1; /* Clock PM disabled */ - - /* Exit latencies */ - struct aspm_latency latency_up; /* Upstream direction exit latency */ - struct aspm_latency latency_dw; /* Downstream direction exit latency */ - /* - * Endpoint acceptable latencies. A pcie downstream port only - * has one slot under it, so at most there are 8 functions. - */ - struct aspm_latency acceptable[8]; }; static int aspm_disabled, aspm_force; @@ -105,6 +91,20 @@ static const char *policy_str[] = { #define LINK_RETRAIN_TIMEOUT HZ +/* + * The L1 PM substate capability is only implemented in function 0 in a + * multi function device. + */ +static struct pci_dev *pci_function_0(struct pci_bus *linkbus) +{ + struct pci_dev *child; + + list_for_each_entry(child, &linkbus->devices, bus_list) + if (PCI_FUNC(child->devfn) == 0) + return child; + return NULL; +} + static int policy_to_aspm_state(struct pcie_link_state *link) { switch (aspm_policy) { @@ -378,8 +378,10 @@ static void encode_l12_threshold(u32 threshold_us, u32 *scale, u32 *value) static void pcie_aspm_check_latency(struct pci_dev *endpoint) { - u32 latency, l1_switch_latency = 0; - struct aspm_latency *acceptable; + u32 latency, encoding, lnkcap_up, lnkcap_dw; + u32 l1_switch_latency = 0, latency_up_l0s; + u32 latency_up_l1, latency_dw_l0s, latency_dw_l1; + u32 acceptable_l0s, acceptable_l1; struct pcie_link_state *link; /* Device not in D0 doesn't need latency check */ @@ -388,17 +390,36 @@ static void pcie_aspm_check_latency(struct pci_dev *endpoint) return; link = endpoint->bus->self->link_state; - acceptable = &link->acceptable[PCI_FUNC(endpoint->devfn)]; + + /* Calculate endpoint L0s acceptable latency */ + encoding = (endpoint->devcap & PCI_EXP_DEVCAP_L0S) >> 6; + acceptable_l0s = calc_l0s_acceptable(encoding); + + /* Calculate endpoint L1 acceptable latency */ + encoding = (endpoint->devcap & PCI_EXP_DEVCAP_L1) >> 9; + acceptable_l1 = calc_l1_acceptable(encoding); while (link) { + struct pci_dev *dev = pci_function_0(link->pdev->subordinate); + + /* Read direction exit latencies */ + pcie_capability_read_dword(link->pdev, PCI_EXP_LNKCAP, + &lnkcap_up); + pcie_capability_read_dword(dev, PCI_EXP_LNKCAP, + &lnkcap_dw); + latency_up_l0s = calc_l0s_latency(lnkcap_up); + latency_up_l1 = calc_l1_latency(lnkcap_up); + latency_dw_l0s = calc_l0s_latency(lnkcap_dw); + latency_dw_l1 = calc_l1_latency(lnkcap_dw); + /* Check upstream direction L0s latency */ if ((link->aspm_capable & ASPM_STATE_L0S_UP) && - (link->latency_up.l0s > acceptable->l0s)) + (latency_up_l0s > acceptable_l0s)) link->aspm_capable &= ~ASPM_STATE_L0S_UP; /* Check downstream direction L0s latency */ if ((link->aspm_capable & ASPM_STATE_L0S_DW) && - (link->latency_dw.l0s > acceptable->l0s)) + (latency_dw_l0s > acceptable_l0s)) link->aspm_capable &= ~ASPM_STATE_L0S_DW; /* * Check L1 latency. @@ -413,9 +434,9 @@ static void pcie_aspm_check_latency(struct pci_dev *endpoint) * L1 exit latencies advertised by a device include L1 * substate latencies (and hence do not do any check). */ - latency = max_t(u32, link->latency_up.l1, link->latency_dw.l1); + latency = max_t(u32, latency_up_l1, latency_dw_l1); if ((link->aspm_capable & ASPM_STATE_L1) && - (latency + l1_switch_latency > acceptable->l1)) + (latency + l1_switch_latency > acceptable_l1)) link->aspm_capable &= ~ASPM_STATE_L1; l1_switch_latency += 1000; @@ -423,20 +444,6 @@ static void pcie_aspm_check_latency(struct pci_dev *endpoint) } } -/* - * The L1 PM substate capability is only implemented in function 0 in a - * multi function device. - */ -static struct pci_dev *pci_function_0(struct pci_bus *linkbus) -{ - struct pci_dev *child; - - list_for_each_entry(child, &linkbus->devices, bus_list) - if (PCI_FUNC(child->devfn) == 0) - return child; - return NULL; -} - static void pci_clear_and_set_dword(struct pci_dev *pdev, int pos, u32 clear, u32 set) { @@ -594,8 +601,6 @@ static void pcie_aspm_cap_init(struct pcie_link_state *link, int blacklist) link->aspm_enabled |= ASPM_STATE_L0S_UP; if (parent_lnkctl & PCI_EXP_LNKCTL_ASPM_L0S) link->aspm_enabled |= ASPM_STATE_L0S_DW; - link->latency_up.l0s = calc_l0s_latency(parent_lnkcap); - link->latency_dw.l0s = calc_l0s_latency(child_lnkcap); /* Setup L1 state */ if (parent_lnkcap & child_lnkcap & PCI_EXP_LNKCAP_ASPM_L1) @@ -603,8 +608,6 @@ static void pcie_aspm_cap_init(struct pcie_link_state *link, int blacklist) if (parent_lnkctl & child_lnkctl & PCI_EXP_LNKCTL_ASPM_L1) link->aspm_enabled |= ASPM_STATE_L1; - link->latency_up.l1 = calc_l1_latency(parent_lnkcap); - link->latency_dw.l1 = calc_l1_latency(child_lnkcap); /* Setup L1 substate */ pci_read_config_dword(parent, parent->l1ss + PCI_L1SS_CAP, @@ -661,22 +664,10 @@ static void pcie_aspm_cap_init(struct pcie_link_state *link, int blacklist) /* Get and check endpoint acceptable latencies */ list_for_each_entry(child, &linkbus->devices, bus_list) { - u32 reg32, encoding; - struct aspm_latency *acceptable = - &link->acceptable[PCI_FUNC(child->devfn)]; - if (pci_pcie_type(child) != PCI_EXP_TYPE_ENDPOINT && pci_pcie_type(child) != PCI_EXP_TYPE_LEG_END) continue; - pcie_capability_read_dword(child, PCI_EXP_DEVCAP, ®32); - /* Calculate endpoint L0s acceptable latency */ - encoding = (reg32 & PCI_EXP_DEVCAP_L0S) >> 6; - acceptable->l0s = calc_l0s_acceptable(encoding); - /* Calculate endpoint L1 acceptable latency */ - encoding = (reg32 & PCI_EXP_DEVCAP_L1) >> 9; - acceptable->l1 = calc_l1_acceptable(encoding); - pcie_aspm_check_latency(child); } } |