| Message ID | 3714448.mG7dE8Q3Fs@kreacher (mailing list archive) |
|---|---|
| State | New, archived |
| Delegated to: | Bjorn Helgaas |
| Headers | show |
| Series | nvme-pci: Allow PCI bus-level PM to be used if ASPM is disabled | expand |
On Thu, Aug 08, 2019 at 12:06:52PM +0200, Rafael J. Wysocki wrote: > From: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > > Add a function returning the mask of currently enabled ASPM link > states for a given device. > > It will be used by the NVMe driver to decide how to handle the > device during system suspend. > > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > --- > > -> v2: > * Move the PCI/PCIe ASPM changes to a separate patch. > * Add the _mask suffix to the new function name. > * Add EXPORT_SYMBOL_GPL() to the new function. > * Avoid adding an unnecessary blank line. > > --- > drivers/pci/pcie/aspm.c | 20 ++++++++++++++++++++ > include/linux/pci.h | 3 +++ > 2 files changed, 23 insertions(+) > > Index: linux-pm/drivers/pci/pcie/aspm.c > =================================================================== > --- linux-pm.orig/drivers/pci/pcie/aspm.c > +++ linux-pm/drivers/pci/pcie/aspm.c > @@ -1170,6 +1170,26 @@ static int pcie_aspm_get_policy(char *bu > module_param_call(policy, pcie_aspm_set_policy, pcie_aspm_get_policy, > NULL, 0644); > > +/* > + * pcie_aspm_enabled_mask - Return the mask of enabled ASPM link states. > + * @pci_device: Target device. > + */ > +u32 pcie_aspm_enabled_mask(struct pci_dev *pci_device) > +{ > + struct pci_dev *bridge = pci_upstream_bridge(pci_device); > + u32 ret; > + > + if (!bridge) > + return 0; > + > + mutex_lock(&aspm_lock); > + ret = bridge->link_state ? bridge->link_state->aspm_enabled : 0; This returns the "aspm_enabled" mask, but the values of that mask are combinations of: ASPM_STATE_L0S_UP ASPM_STATE_L0S_DW ASPM_STATE_L1 ... which are defined internally in drivers/pci/pcie/aspm.c and not visible to the caller of pcie_aspm_enabled_mask(). If there's no need for the actual mask (the current caller doesn't seem to use it), maybe this could be a boolean? > + mutex_unlock(&aspm_lock); > + > + return ret; > +} > +EXPORT_SYMBOL_GPL(pcie_aspm_enabled_mask); > + > #ifdef CONFIG_PCIEASPM_DEBUG > static ssize_t link_state_show(struct device *dev, > struct device_attribute *attr, > Index: linux-pm/include/linux/pci.h > =================================================================== > --- linux-pm.orig/include/linux/pci.h > +++ linux-pm/include/linux/pci.h > @@ -1567,8 +1567,11 @@ extern bool pcie_ports_native; > > #ifdef CONFIG_PCIEASPM > bool pcie_aspm_support_enabled(void); > +u32 pcie_aspm_enabled_mask(struct pci_dev *pci_device); > #else > static inline bool pcie_aspm_support_enabled(void) { return false; } > +static inline u32 pcie_aspm_enabled_mask(struct pci_dev *pci_device) > +{ return 0; } > #endif > > #ifdef CONFIG_PCIEAER > > >
On Thu, Aug 8, 2019 at 3:15 PM Bjorn Helgaas <helgaas@kernel.org> wrote: > > On Thu, Aug 08, 2019 at 12:06:52PM +0200, Rafael J. Wysocki wrote: > > From: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > > > > Add a function returning the mask of currently enabled ASPM link > > states for a given device. > > > > It will be used by the NVMe driver to decide how to handle the > > device during system suspend. > > > > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > > --- > > > > -> v2: > > * Move the PCI/PCIe ASPM changes to a separate patch. > > * Add the _mask suffix to the new function name. > > * Add EXPORT_SYMBOL_GPL() to the new function. > > * Avoid adding an unnecessary blank line. > > > > --- > > drivers/pci/pcie/aspm.c | 20 ++++++++++++++++++++ > > include/linux/pci.h | 3 +++ > > 2 files changed, 23 insertions(+) > > > > Index: linux-pm/drivers/pci/pcie/aspm.c > > =================================================================== > > --- linux-pm.orig/drivers/pci/pcie/aspm.c > > +++ linux-pm/drivers/pci/pcie/aspm.c > > @@ -1170,6 +1170,26 @@ static int pcie_aspm_get_policy(char *bu > > module_param_call(policy, pcie_aspm_set_policy, pcie_aspm_get_policy, > > NULL, 0644); > > > > +/* > > + * pcie_aspm_enabled_mask - Return the mask of enabled ASPM link states. > > + * @pci_device: Target device. > > + */ > > +u32 pcie_aspm_enabled_mask(struct pci_dev *pci_device) > > +{ > > + struct pci_dev *bridge = pci_upstream_bridge(pci_device); > > + u32 ret; > > + > > + if (!bridge) > > + return 0; > > + > > + mutex_lock(&aspm_lock); > > + ret = bridge->link_state ? bridge->link_state->aspm_enabled : 0; > > This returns the "aspm_enabled" mask, but the values of that mask are > combinations of: > > ASPM_STATE_L0S_UP > ASPM_STATE_L0S_DW > ASPM_STATE_L1 > ... > > which are defined internally in drivers/pci/pcie/aspm.c and not > visible to the caller of pcie_aspm_enabled_mask(). If there's no need > for the actual mask (the current caller doesn't seem to use it), maybe > this could be a boolean? Yes, it can be a boolean. > > > + mutex_unlock(&aspm_lock); > > + > > + return ret; > > +} > > +EXPORT_SYMBOL_GPL(pcie_aspm_enabled_mask); > > + > > #ifdef CONFIG_PCIEASPM_DEBUG > > static ssize_t link_state_show(struct device *dev, > > struct device_attribute *attr, > > Index: linux-pm/include/linux/pci.h > > =================================================================== > > --- linux-pm.orig/include/linux/pci.h > > +++ linux-pm/include/linux/pci.h > > @@ -1567,8 +1567,11 @@ extern bool pcie_ports_native; > > > > #ifdef CONFIG_PCIEASPM > > bool pcie_aspm_support_enabled(void); > > +u32 pcie_aspm_enabled_mask(struct pci_dev *pci_device); > > #else > > static inline bool pcie_aspm_support_enabled(void) { return false; } > > +static inline u32 pcie_aspm_enabled_mask(struct pci_dev *pci_device) > > +{ return 0; } > > #endif > > > > #ifdef CONFIG_PCIEAER > > > > > >
Index: linux-pm/drivers/pci/pcie/aspm.c =================================================================== --- linux-pm.orig/drivers/pci/pcie/aspm.c +++ linux-pm/drivers/pci/pcie/aspm.c @@ -1170,6 +1170,26 @@ static int pcie_aspm_get_policy(char *bu module_param_call(policy, pcie_aspm_set_policy, pcie_aspm_get_policy, NULL, 0644); +/* + * pcie_aspm_enabled_mask - Return the mask of enabled ASPM link states. + * @pci_device: Target device. + */ +u32 pcie_aspm_enabled_mask(struct pci_dev *pci_device) +{ + struct pci_dev *bridge = pci_upstream_bridge(pci_device); + u32 ret; + + if (!bridge) + return 0; + + mutex_lock(&aspm_lock); + ret = bridge->link_state ? bridge->link_state->aspm_enabled : 0; + mutex_unlock(&aspm_lock); + + return ret; +} +EXPORT_SYMBOL_GPL(pcie_aspm_enabled_mask); + #ifdef CONFIG_PCIEASPM_DEBUG static ssize_t link_state_show(struct device *dev, struct device_attribute *attr, Index: linux-pm/include/linux/pci.h =================================================================== --- linux-pm.orig/include/linux/pci.h +++ linux-pm/include/linux/pci.h @@ -1567,8 +1567,11 @@ extern bool pcie_ports_native; #ifdef CONFIG_PCIEASPM bool pcie_aspm_support_enabled(void); +u32 pcie_aspm_enabled_mask(struct pci_dev *pci_device); #else static inline bool pcie_aspm_support_enabled(void) { return false; } +static inline u32 pcie_aspm_enabled_mask(struct pci_dev *pci_device) +{ return 0; } #endif #ifdef CONFIG_PCIEAER