From 642c92da36ae0bed3c31fdd408411ab95f4e326b Mon Sep 17 00:00:00 2001 From: Taku Izumi Date: Tue, 30 Oct 2012 15:26:18 +0900 Subject: PCI: Don't pass pci_dev to pci_ext_cfg_avail() pci_ext_cfg_avail() doesn't use the "struct pci_dev *" passed to it, and there's no requirement that a host bridge even be represented by a pci_dev. This drops the pci_ext_cfg_avail() parameter. [bhelgaas: changelog] Signed-off-by: Taku Izumi Signed-off-by: Bjorn Helgaas --- drivers/pci/pci.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) (limited to 'drivers/pci/pci.c') diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 54858838f098..01b68bfa2321 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -3833,14 +3833,13 @@ static void __devinit pci_no_domains(void) } /** - * pci_ext_cfg_enabled - can we access extended PCI config space? - * @dev: The PCI device of the root bridge. + * pci_ext_cfg_avail - can we access extended PCI config space? * * Returns 1 if we can access PCI extended config space (offsets * greater than 0xff). This is the default implementation. Architecture * implementations can override this. */ -int __weak pci_ext_cfg_avail(struct pci_dev *dev) +int __weak pci_ext_cfg_avail(void) { return 1; } -- cgit v1.2.3 From 6e965e0d0e1d102c261326b06338d3385ea55f97 Mon Sep 17 00:00:00 2001 From: Huang Ying Date: Fri, 26 Oct 2012 13:07:51 +0800 Subject: PCI/PM: Add comments for PME poll support for PCIe There are comments on why PME poll support is necessary for PCI devices, but not for PCIe devices. That may lead to misunderstanding that PME poll is only necessary for PCI devices. So add comments related to PCIe PME poll to make it more clear. The content of comments comes from the changelog of commit: 379021d5c0899fcf9410cae4ca7a59a5a94ca769 Signed-off-by: Huang Ying Signed-off-by: Bjorn Helgaas Acked-by: Rafael J. Wysocki --- drivers/pci/pci.c | 28 +++++++++++++++++++--------- 1 file changed, 19 insertions(+), 9 deletions(-) (limited to 'drivers/pci/pci.c') diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 54858838f098..485cfa9af2ef 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -1578,15 +1578,25 @@ void pci_pme_active(struct pci_dev *dev, bool enable) pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr); - /* PCI (as opposed to PCIe) PME requires that the device have - its PME# line hooked up correctly. Not all hardware vendors - do this, so the PME never gets delivered and the device - remains asleep. The easiest way around this is to - periodically walk the list of suspended devices and check - whether any have their PME flag set. The assumption is that - we'll wake up often enough anyway that this won't be a huge - hit, and the power savings from the devices will still be a - win. */ + /* + * PCI (as opposed to PCIe) PME requires that the device have + * its PME# line hooked up correctly. Not all hardware vendors + * do this, so the PME never gets delivered and the device + * remains asleep. The easiest way around this is to + * periodically walk the list of suspended devices and check + * whether any have their PME flag set. The assumption is that + * we'll wake up often enough anyway that this won't be a huge + * hit, and the power savings from the devices will still be a + * win. + * + * Although PCIe uses in-band PME message instead of PME# line + * to report PME, PME does not work for some PCIe devices in + * reality. For example, there are devices that set their PME + * status bits, but don't really bother to send a PME message; + * there are PCI Express Root Ports that don't bother to + * trigger interrupts when they receive PME messages from the + * devices below. So PME poll is used for PCIe devices too. + */ if (dev->pme_poll) { struct pci_pme_device *pme_dev; -- cgit v1.2.3 From 967577b062417b4e4b8e27b711220f4124f5153a Mon Sep 17 00:00:00 2001 From: Huang Ying Date: Tue, 20 Nov 2012 16:08:22 +0800 Subject: PCI/PM: Keep runtime PM enabled for unbound PCI devices For unbound PCI devices, what we need is: - Always in D0 state, because some devices do not work again after being put into D3 by the PCI bus. - In SUSPENDED state if allowed, so that the parent devices can still be put into low power state. To satisfy these requirements, the runtime PM for the unbound PCI devices are disabled and set to SUSPENDED state. One issue of this solution is that the PCI devices will be put into SUSPENDED state even if the SUSPENDED state is forbidden via the sysfs interface (.../power/control) of the device. This is not an issue for most devices, because most PCI devices are not used at all if unbound. But there are exceptions. For example, unbound VGA card can be used for display, but suspending its parents makes it stop working. To fix the issue, we keep the runtime PM enabled when the PCI devices are unbound. But the runtime PM callbacks will do nothing if the PCI devices are unbound. This way, we can put the PCI devices into SUSPENDED state without putting the PCI devices into D3 state. Reference: https://bugzilla.kernel.org/show_bug.cgi?id=48201 Signed-off-by: Huang Ying Signed-off-by: Bjorn Helgaas Acked-by: Alan Stern Acked-by: Rafael J. Wysocki CC: stable@vger.kernel.org # v3.6+ --- drivers/pci/pci.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'drivers/pci/pci.c') diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index aabf64798bda..8e06adb9898f 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -1900,6 +1900,8 @@ void pci_pm_init(struct pci_dev *dev) u16 pmc; pm_runtime_forbid(&dev->dev); + pm_runtime_set_active(&dev->dev); + pm_runtime_enable(&dev->dev); device_enable_async_suspend(&dev->dev); dev->wakeup_prepared = false; -- cgit v1.2.3 From eca0d4676d8e29c209ddce0c0c1755472ffc70a6 Mon Sep 17 00:00:00 2001 From: Matthew Garrett Date: Wed, 5 Dec 2012 14:33:27 -0700 Subject: PCI: Add pcibios_add_device Platforms may want to provide architecture-specific functionality during PCI enumeration. Add a pcibios_add_device() call that architectures can override to do so. Signed-off-by: Matthew Garrett Signed-off-by: Bjorn Helgaas Tested-by: Seth Forshee --- drivers/pci/pci.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'drivers/pci/pci.c') diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 54858838f098..fa0ddd51a216 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -1333,6 +1333,19 @@ void pcim_pin_device(struct pci_dev *pdev) dr->pinned = 1; } +/* + * pcibios_add_device - provide arch specific hooks when adding device dev + * @dev: the PCI device being added + * + * Permits the platform to provide architecture specific functionality when + * devices are added. This is the default implementation. Architecture + * implementations can override this. + */ +int __weak pcibios_add_device (struct pci_dev *dev) +{ + return 0; +} + /** * pcibios_disable_device - disable arch specific PCI resources for device dev * @dev: the PCI device to disable -- cgit v1.2.3