From 71a83bd727cc31c5fe960c3758cb396267ff710e Mon Sep 17 00:00:00 2001 From: Zheng Yan Date: Sat, 23 Jun 2012 10:23:49 +0800 Subject: PCI/PM: add runtime PM support to PCIe port This patch adds runtime PM support to PCIe port. This is needed by PCIe D3cold support, where PCIe device without ACPI node may be powered on/off by PCIe port. Because runtime suspend is broken for some chipsets, a black list is used to disable runtime PM support for these chipsets. Reviewed-by: Rafael J. Wysocki Signed-off-by: Zheng Yan Signed-off-by: Huang Ying Signed-off-by: Bjorn Helgaas --- drivers/pci/pcie/portdrv_pci.c | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) (limited to 'drivers/pci/pcie') diff --git a/drivers/pci/pcie/portdrv_pci.c b/drivers/pci/pcie/portdrv_pci.c index e0610bda1dea..7c576b9aa01d 100644 --- a/drivers/pci/pcie/portdrv_pci.c +++ b/drivers/pci/pcie/portdrv_pci.c @@ -11,6 +11,7 @@ #include #include #include +#include #include #include #include @@ -99,6 +100,15 @@ static int pcie_port_resume_noirq(struct device *dev) return 0; } +#ifdef CONFIG_PM_RUNTIME +static int pcie_port_runtime_pm(struct device *dev) +{ + return 0; +} +#else +#define pcie_port_runtime_pm NULL +#endif + static const struct dev_pm_ops pcie_portdrv_pm_ops = { .suspend = pcie_port_device_suspend, .resume = pcie_port_device_resume, @@ -107,6 +117,8 @@ static const struct dev_pm_ops pcie_portdrv_pm_ops = { .poweroff = pcie_port_device_suspend, .restore = pcie_port_device_resume, .resume_noirq = pcie_port_resume_noirq, + .runtime_suspend = pcie_port_runtime_pm, + .runtime_resume = pcie_port_runtime_pm, }; #define PCIE_PORTDRV_PM_OPS (&pcie_portdrv_pm_ops) @@ -116,6 +128,14 @@ static const struct dev_pm_ops pcie_portdrv_pm_ops = { #define PCIE_PORTDRV_PM_OPS NULL #endif /* !PM */ +/* + * PCIe port runtime suspend is broken for some chipsets, so use a + * black list to disable runtime PM for these chipsets. + */ +static const struct pci_device_id port_runtime_pm_black_list[] = { + { /* end: all zeroes */ } +}; + /* * pcie_portdrv_probe - Probe PCI-Express port devices * @dev: PCI-Express port device being probed @@ -144,12 +164,16 @@ static int __devinit pcie_portdrv_probe(struct pci_dev *dev, return status; pci_save_state(dev); + if (!pci_match_id(port_runtime_pm_black_list, dev)) + pm_runtime_put_noidle(&dev->dev); return 0; } static void pcie_portdrv_remove(struct pci_dev *dev) { + if (!pci_match_id(port_runtime_pm_black_list, dev)) + pm_runtime_get_noresume(&dev->dev); pcie_port_device_remove(dev); pci_disable_device(dev); } -- cgit v1.2.1 From 448bd857d48e69b33ef323739dc6d8ca20d4cda7 Mon Sep 17 00:00:00 2001 From: Huang Ying Date: Sat, 23 Jun 2012 10:23:51 +0800 Subject: PCI/PM: add PCIe runtime D3cold support This patch adds runtime D3cold support and corresponding ACPI platform support. This patch only enables runtime D3cold support; it does not enable D3cold support during system suspend/hibernate. D3cold is the deepest power saving state for a PCIe device, where its main power is removed. While it is in D3cold, you can't access the device at all, not even its configuration space (which is still accessible in D3hot). Therefore the PCI PM registers can not be used to transition into/out of the D3cold state; that must be done by platform logic such as ACPI _PR3. To support wakeup from D3cold, a system may provide auxiliary power, which allows a device to request wakeup using a Beacon or the sideband WAKE# signal. WAKE# is usually connected to platform logic such as ACPI GPE. This is quite different from other power saving states, where devices request wakeup via a PME message on the PCIe link. Some devices, such as those in plug-in slots, have no direct platform logic. For example, there is usually no ACPI _PR3 for them. D3cold support for these devices can be done via the PCIe Downstream Port leading to the device. When the PCIe port is powered on/off, the device is powered on/off too. Wakeup events from the device will be notified to the corresponding PCIe port. For more information about PCIe D3cold and corresponding ACPI support, please refer to: - PCI Express Base Specification Revision 2.0 - Advanced Configuration and Power Interface Specification Revision 5.0 [bhelgaas: changelog] Reviewed-by: Rafael J. Wysocki Originally-by: Zheng Yan Signed-off-by: Huang Ying Signed-off-by: Bjorn Helgaas --- drivers/pci/pcie/portdrv_pci.c | 44 ++++++++++++++++++++++++++++++++++++++---- 1 file changed, 40 insertions(+), 4 deletions(-) (limited to 'drivers/pci/pcie') diff --git a/drivers/pci/pcie/portdrv_pci.c b/drivers/pci/pcie/portdrv_pci.c index 7c576b9aa01d..3a7eefcb270a 100644 --- a/drivers/pci/pcie/portdrv_pci.c +++ b/drivers/pci/pcie/portdrv_pci.c @@ -101,12 +101,48 @@ static int pcie_port_resume_noirq(struct device *dev) } #ifdef CONFIG_PM_RUNTIME -static int pcie_port_runtime_pm(struct device *dev) +struct d3cold_info { + bool no_d3cold; + unsigned int d3cold_delay; +}; + +static int pci_dev_d3cold_info(struct pci_dev *pdev, void *data) +{ + struct d3cold_info *info = data; + + info->d3cold_delay = max_t(unsigned int, pdev->d3cold_delay, + info->d3cold_delay); + if (pdev->no_d3cold) + info->no_d3cold = true; + return 0; +} + +static int pcie_port_runtime_suspend(struct device *dev) +{ + struct pci_dev *pdev = to_pci_dev(dev); + struct d3cold_info d3cold_info = { + .no_d3cold = false, + .d3cold_delay = PCI_PM_D3_WAIT, + }; + + /* + * If any subordinate device disable D3cold, we should not put + * the port into D3cold. The D3cold delay of port should be + * the max of that of all subordinate devices. + */ + pci_walk_bus(pdev->subordinate, pci_dev_d3cold_info, &d3cold_info); + pdev->no_d3cold = d3cold_info.no_d3cold; + pdev->d3cold_delay = d3cold_info.d3cold_delay; + return 0; +} + +static int pcie_port_runtime_resume(struct device *dev) { return 0; } #else -#define pcie_port_runtime_pm NULL +#define pcie_port_runtime_suspend NULL +#define pcie_port_runtime_resume NULL #endif static const struct dev_pm_ops pcie_portdrv_pm_ops = { @@ -117,8 +153,8 @@ static const struct dev_pm_ops pcie_portdrv_pm_ops = { .poweroff = pcie_port_device_suspend, .restore = pcie_port_device_resume, .resume_noirq = pcie_port_resume_noirq, - .runtime_suspend = pcie_port_runtime_pm, - .runtime_resume = pcie_port_runtime_pm, + .runtime_suspend = pcie_port_runtime_suspend, + .runtime_resume = pcie_port_runtime_resume, }; #define PCIE_PORTDRV_PM_OPS (&pcie_portdrv_pm_ops) -- cgit v1.2.1