From f1c0ca29ae72bc0c10282eada66c8a792ee98482 Mon Sep 17 00:00:00 2001 From: Kenji Kaneshige Date: Wed, 19 Aug 2009 10:59:52 +0900 Subject: [PATCH] PCI ASPM: introduce disable flag Introduce 'aspm_disable' flag to manage disabled ASPM state more robust way. Acked-by: Shaohua Li Signed-off-by: Kenji Kaneshige Signed-off-by: Jesse Barnes --- drivers/pci/pcie/aspm.c | 41 ++++++++++++++++++++++++----------------- 1 file changed, 24 insertions(+), 17 deletions(-) diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c index 0800c5146826..8f7884a8bc2e 100644 --- a/drivers/pci/pcie/aspm.c +++ b/drivers/pci/pcie/aspm.c @@ -43,6 +43,7 @@ struct pcie_link_state { u32 aspm_support:2; /* Supported ASPM state */ u32 aspm_enabled:2; /* Enabled ASPM state */ u32 aspm_default:2; /* Default ASPM state by BIOS */ + u32 aspm_disable:2; /* Disabled ASPM state */ /* Clock PM state */ u32 clkpm_capable:1; /* Clock PM capable? */ @@ -322,10 +323,9 @@ static void pcie_aspm_cap_init(struct pcie_link_state *link, int blacklist) struct pci_bus *linkbus = parent->subordinate; if (blacklist) { - /* Set support state to 0, so we will disable ASPM later */ - link->aspm_support = 0; - link->aspm_default = 0; + /* Set enabled/disable so that we will disable ASPM later */ link->aspm_enabled = PCIE_LINK_STATE_L0S | PCIE_LINK_STATE_L1; + link->aspm_disable = PCIE_LINK_STATE_L0S | PCIE_LINK_STATE_L1; return; } @@ -348,6 +348,17 @@ static void pcie_aspm_cap_init(struct pcie_link_state *link, int blacklist) /* Save default state */ link->aspm_default = link->aspm_enabled; + /* + * If the downstream component has pci bridge function, don't + * do ASPM for now. + */ + list_for_each_entry(child, &linkbus->devices, bus_list) { + if (child->pcie_type == PCI_EXP_TYPE_PCI_BRIDGE) { + link->aspm_disable = + PCIE_LINK_STATE_L0S | PCIE_LINK_STATE_L1; + break; + } + } if (!link->aspm_support) return; @@ -458,14 +469,10 @@ static void __pcie_aspm_config_link(struct pcie_link_state *link, u32 state) struct pci_dev *child, *parent = link->pdev; struct pci_bus *linkbus = parent->subordinate; - /* - * If the downstream component has pci bridge function, don't - * do ASPM now. - */ - list_for_each_entry(child, &linkbus->devices, bus_list) { - if (child->pcie_type == PCI_EXP_TYPE_PCI_BRIDGE) - return; - } + state &= ~link->aspm_disable; + /* Nothing to do if the link is already in the requested state */ + if (link->aspm_enabled == state) + return; /* * Spec 2.0 suggests all functions should be configured the * same setting for ASPM. Enabling ASPM L1 should be done in @@ -719,7 +726,7 @@ void pcie_aspm_pm_state_change(struct pci_dev *pdev) void pci_disable_link_state(struct pci_dev *pdev, int state) { struct pci_dev *parent = pdev->bus->self; - struct pcie_link_state *link_state; + struct pcie_link_state *link; if (aspm_disabled || !pdev->is_pcie) return; @@ -731,12 +738,12 @@ void pci_disable_link_state(struct pci_dev *pdev, int state) down_read(&pci_bus_sem); mutex_lock(&aspm_lock); - link_state = parent->link_state; - link_state->aspm_support &= ~state; - __pcie_aspm_configure_link_state(link_state, link_state->aspm_enabled); + link = parent->link_state; + link->aspm_disable |= state; + __pcie_aspm_configure_link_state(link, link->aspm_enabled); if (state & PCIE_LINK_STATE_CLKPM) { - link_state->clkpm_capable = 0; - pcie_set_clkpm(link_state, 0); + link->clkpm_capable = 0; + pcie_set_clkpm(link, 0); } mutex_unlock(&aspm_lock); up_read(&pci_bus_sem); -- 2.30.2