Call pci_aspm_init() for every device, maybe from pci_init_capabilities()
- for bridges, have pcie_aspm_init_link_state() allocate a
link_state, regardless of whether it currently has any children,
and save the ASPM settings done by firmware
- for endpoints, have pcie_aspm_init_link_state() do the actual ASPM
setup of the link as it currently does
Signed-off-by: Sinan Kaya <okaya@xxxxxxxxxxxxxx>
---
drivers/pci/pcie/aspm.c | 82 +++++++++++++++++++++++++++++++++++++++++++------
drivers/pci/probe.c | 3 ++
include/linux/pci.h | 6 ++++
3 files changed, 81 insertions(+), 10 deletions(-)
diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
index 453558d..ed67710 100644
--- a/drivers/pci/pcie/aspm.c
+++ b/drivers/pci/pcie/aspm.c
@@ -383,15 +383,14 @@ static void pcie_aspm_cap_post_scan(struct pcie_link_state *link, int blacklist)
}
}
-static void pcie_aspm_cap_init(struct pcie_link_state *link)
+static void pcie_aspm_cap_init(struct pcie_link_state *link,
+ struct pci_dev *child)
{
- struct pci_dev *child, *parent = link->pdev;
- struct pci_bus *linkbus = parent->subordinate;
+ struct pci_dev *parent = link->pdev;
struct aspm_register_info upreg, dwreg;
/* Get upstream/downstream components' register state */
pcie_get_aspm_reg(parent, &upreg);
- child = list_entry(linkbus->devices.next, struct pci_dev, bus_list);
pcie_get_aspm_reg(child, &dwreg);
/*
@@ -576,6 +575,71 @@ static struct pcie_link_state *alloc_pcie_link_state(struct pci_dev *pdev)
* It is called after the pcie and its children devices are scanned.
* @pdev: the root port or switch downstream port
*/
+int pci_aspm_init(struct pci_dev *pdev)
+{
+ int ret;
+ struct pcie_link_state *link;
+
+ if (!aspm_support_enabled)
+ return 0;
+
+ if (pdev->link_state)
+ return 0;
+
+ /* VIA has a strange chipset, root port is under a bridge */
+ if (pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT &&
+ pdev->bus->self)
+ return 0;
+
+ down_read(&pci_bus_sem);
+ mutex_lock(&aspm_lock);
+
+ if (pdev->has_secondary_link) {
+ link = alloc_pcie_link_state(pdev);
+ WARN_ON(!link);
+ if (!link) {
+ ret = -ENOMEM;
+ goto unlock;
+ }
+ } else {
+ WARN_ON(!pdev->bus);
+ if (!pdev->bus) {
+ ret = -ENODEV;
+ goto unlock;
+ }
+
+ WARN_ON(!pdev->bus->self);
+ if (!pdev->bus->self) {
+ ret = -ENODEV;
+ goto unlock;
+ }
+
+ WARN_ON(!pdev->bus->self->link_state);
+ if (!pdev->bus->self->link_state) {
+ ret = -ENODEV;
+ goto unlock;
+ }
+
+ link = pdev->bus->self->link_state;
+
+ /* Setup initial ASPM state. */
+ pcie_aspm_cap_init(link, pdev);
+
+ }
+
+ ret = 0;
+unlock:
+ mutex_unlock(&aspm_lock);
+ up_read(&pci_bus_sem);
+
+ return ret;
+}
+
+/*
+ * pcie_aspm_init_link_state: Initiate PCI express link state.
+ * It is called after the pcie and its children devices are scanned.
+ * @pdev: the root port or switch downstream port
+ */
void pcie_aspm_init_link_state(struct pci_dev *pdev)
{
struct pcie_link_state *link;
@@ -584,9 +648,11 @@ void pcie_aspm_init_link_state(struct pci_dev *pdev)
if (!aspm_support_enabled)
return;
- if (pdev->link_state)
+ if (!pdev->link_state)
return;
+ link = pdev->link_state;
+
/*
* We allocate pcie_link_state for the component on the upstream
* end of a Link, so there's nothing to do unless this device has a
@@ -605,15 +671,12 @@ void pcie_aspm_init_link_state(struct pci_dev *pdev)
goto out;
mutex_lock(&aspm_lock);
- link = alloc_pcie_link_state(pdev);
- if (!link)
- goto unlock;
+
/*
* Setup initial ASPM state. Note that we need to configure
* upstream links also because capable state of them can be
* update through pcie_aspm_cap_init().
*/
- pcie_aspm_cap_init(link);
pcie_aspm_cap_post_scan(link, blacklist);
/* Setup initial Clock PM state */
@@ -632,7 +695,6 @@ void pcie_aspm_init_link_state(struct pci_dev *pdev)
pcie_set_clkpm(link, policy_to_clkpm_state(link));
}
-unlock:
mutex_unlock(&aspm_lock);
out:
up_read(&pci_bus_sem);
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 204960e..d7f10fb 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -1818,6 +1818,9 @@ static void pci_init_capabilities(struct pci_dev *dev)
/* Advanced Error Reporting */
pci_aer_init(dev);
+
+ /* Active State Power Management */
+ pci_aspm_init(dev);
}
/*
diff --git a/include/linux/pci.h b/include/linux/pci.h
index e2d1a12..97e13f0 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1418,6 +1418,12 @@ static inline void pci_no_aer(void) { }
static inline int pci_aer_init(struct pci_dev *d) { return -ENODEV; }
#endif
+#ifdef CONFIG_PCIEASPM
+int pci_aspm_init(struct pci_dev *pdev);
+#else
+static inline int pci_aspm_init(struct pci_dev *pdev) { return -ENODEV; };
+#endif
+
#ifdef CONFIG_PCIE_ECRC
void pcie_set_ecrc_checking(struct pci_dev *dev);
void pcie_ecrc_get_policy(char *str);
--
1.9.1
