#include <linux/string.h>
#include <linux/log2.h>
#include <linux/pci-aspm.h>
+#include <linux/pm_wakeup.h>
#include <asm/dma.h> /* isa_dma_bridge_buggy */
#include "pci.h"
int pci_set_platform_pm(struct pci_platform_pm_ops *ops)
{
- if (!ops->is_manageable || !ops->set_state || !ops->choose_state)
+ if (!ops->is_manageable || !ops->set_state || !ops->choose_state
+ || !ops->sleep_wake || !ops->can_wakeup)
return -EINVAL;
pci_platform_pm = ops;
return 0;
pci_platform_pm->choose_state(dev) : PCI_POWER_ERROR;
}
+static inline bool platform_pci_can_wakeup(struct pci_dev *dev)
+{
+ return pci_platform_pm ? pci_platform_pm->can_wakeup(dev) : false;
+}
+
+static inline int platform_pci_sleep_wake(struct pci_dev *dev, bool enable)
+{
+ return pci_platform_pm ?
+ pci_platform_pm->sleep_wake(dev, enable) : -ENODEV;
+}
+
/**
* pci_raw_set_power_state - Use PCI PM registers to set the power state of
* given PCI device
* @dev: PCI device to handle.
- * @pm: PCI PM capability offset of the device.
* @state: PCI power state (D0, D1, D2, D3hot) to put the device into.
*
* RETURN VALUE:
* 0 if device's power state has been successfully changed.
*/
static int
-pci_raw_set_power_state(struct pci_dev *dev, int pm, pci_power_t state)
+pci_raw_set_power_state(struct pci_dev *dev, pci_power_t state)
{
- u16 pmcsr, pmc;
+ u16 pmcsr;
bool need_restore = false;
- if (!pm)
+ if (!dev->pm_cap)
return -EIO;
if (state < PCI_D0 || state > PCI_D3hot)
return -EINVAL;
}
- pci_read_config_word(dev, pm + PCI_PM_PMC, &pmc);
-
- if ((pmc & PCI_PM_CAP_VER_MASK) > 3) {
- dev_err(&dev->dev, "unsupported PM cap regs version (%u)\n",
- pmc & PCI_PM_CAP_VER_MASK);
- return -EIO;
- }
-
/* check if this device supports the desired state */
- if ((state == PCI_D1 && !(pmc & PCI_PM_CAP_D1))
- || (state == PCI_D2 && !(pmc & PCI_PM_CAP_D2)))
+ if ((state == PCI_D1 && !dev->d1_support)
+ || (state == PCI_D2 && !dev->d2_support))
return -EIO;
- pci_read_config_word(dev, pm + PCI_PM_CTRL, &pmcsr);
+ pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
/* If we're (effectively) in D3, force entire word to 0.
* This doesn't affect PME_Status, disables PME_En, and
}
/* enter specified state */
- pci_write_config_word(dev, pm + PCI_PM_CTRL, pmcsr);
+ pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
/* Mandatory power management transition delays */
/* see PCI PM 1.1 5.6.1 table 18 */
* pci_update_current_state - Read PCI power state of given device from its
* PCI PM registers and cache it
* @dev: PCI device to handle.
- * @pm: PCI PM capability offset of the device.
*/
-static void pci_update_current_state(struct pci_dev *dev, int pm)
+static void pci_update_current_state(struct pci_dev *dev)
{
- if (pm) {
+ if (dev->pm_cap) {
u16 pmcsr;
- pci_read_config_word(dev, pm + PCI_PM_CTRL, &pmcsr);
+ pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
}
}
*/
int pci_set_power_state(struct pci_dev *dev, pci_power_t state)
{
- int pm, error;
+ int error;
/* bound the state we're entering */
if (state > PCI_D3hot)
*/
return 0;
- /* Find PCI PM capability in the list */
- pm = pci_find_capability(dev, PCI_CAP_ID_PM);
-
if (state == PCI_D0 && platform_pci_power_manageable(dev)) {
/*
* Allow the platform to change the state, for example via ACPI
*/
int ret = platform_pci_set_power_state(dev, PCI_D0);
if (!ret)
- pci_update_current_state(dev, pm);
+ pci_update_current_state(dev);
}
- error = pci_raw_set_power_state(dev, pm, state);
+ error = pci_raw_set_power_state(dev, state);
if (state > PCI_D0 && platform_pci_power_manageable(dev)) {
/* Allow the platform to finalize the transition */
int ret = platform_pci_set_power_state(dev, state);
if (!ret) {
- pci_update_current_state(dev, pm);
+ pci_update_current_state(dev);
error = 0;
}
}
return pcibios_set_pcie_reset_state(dev, state);
}
+/**
+ * pci_pme_capable - check the capability of PCI device to generate PME#
+ * @dev: PCI device to handle.
+ * @state: PCI state from which device will issue PME#.
+ */
+bool pci_pme_capable(struct pci_dev *dev, pci_power_t state)
+{
+ if (!dev->pm_cap)
+ return false;
+
+ return !!(dev->pme_support & (1 << state));
+}
+
+/**
+ * pci_pme_active - enable or disable PCI device's PME# function
+ * @dev: PCI device to handle.
+ * @enable: 'true' to enable PME# generation; 'false' to disable it.
+ *
+ * The caller must verify that the device is capable of generating PME# before
+ * calling this function with @enable equal to 'true'.
+ */
+static void pci_pme_active(struct pci_dev *dev, bool enable)
+{
+ u16 pmcsr;
+
+ if (!dev->pm_cap)
+ return;
+
+ pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
+ /* Clear PME_Status by writing 1 to it and enable PME# */
+ pmcsr |= PCI_PM_CTRL_PME_STATUS | PCI_PM_CTRL_PME_ENABLE;
+ if (!enable)
+ pmcsr &= ~PCI_PM_CTRL_PME_ENABLE;
+
+ pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
+
+ dev_printk(KERN_INFO, &dev->dev, "PME# %s\n",
+ enable ? "enabled" : "disabled");
+}
+
/**
* pci_enable_wake - enable PCI device as wakeup event source
* @dev: PCI device affected
* called automatically by this routine.
*
* Devices with legacy power management (no standard PCI PM capabilities)
- * always require such platform hooks. Depending on the platform, devices
- * supporting the standard PCI PME# signal may require such platform hooks;
- * they always update bits in config space to allow PME# generation.
+ * always require such platform hooks.
*
- * -EIO is returned if the device can't ever be a wakeup event source.
- * -EINVAL is returned if the device can't generate wakeup events from
- * the specified PCI state. Returns zero if the operation is successful.
+ * RETURN VALUE:
+ * 0 is returned on success
+ * -EINVAL is returned if device is not supposed to wake up the system
+ * Error code depending on the platform is returned if both the platform and
+ * the native mechanism fail to enable the generation of wake-up events
*/
int pci_enable_wake(struct pci_dev *dev, pci_power_t state, int enable)
{
- int pm;
- int status;
- u16 value;
-
- /* Note that drivers should verify device_may_wakeup(&dev->dev)
- * before calling this function. Platform code should report
- * errors when drivers try to enable wakeup on devices that
- * can't issue wakeups, or on which wakeups were disabled by
- * userspace updating the /sys/devices.../power/wakeup file.
+ int error = 0;
+ bool pme_done = false;
+
+ if (!device_may_wakeup(&dev->dev))
+ return -EINVAL;
+
+ /*
+ * According to "PCI System Architecture" 4th ed. by Tom Shanley & Don
+ * Anderson we should be doing PME# wake enable followed by ACPI wake
+ * enable. To disable wake-up we call the platform first, for symmetry.
*/
- status = call_platform_enable_wakeup(&dev->dev, enable);
+ if (!enable && platform_pci_can_wakeup(dev))
+ error = platform_pci_sleep_wake(dev, false);
- /* find PCI PM capability in list */
- pm = pci_find_capability(dev, PCI_CAP_ID_PM);
+ if (!enable || pci_pme_capable(dev, state)) {
+ pci_pme_active(dev, enable);
+ pme_done = true;
+ }
- /* If device doesn't support PM Capabilities, but caller wants to
- * disable wake events, it's a NOP. Otherwise fail unless the
- * platform hooks handled this legacy device already.
- */
- if (!pm)
- return enable ? status : 0;
+ if (enable && platform_pci_can_wakeup(dev))
+ error = platform_pci_sleep_wake(dev, true);
- /* Check device's ability to generate PME# */
- pci_read_config_word(dev,pm+PCI_PM_PMC,&value);
+ return pme_done ? 0 : error;
+}
+
+/**
+ */
+pci_power_t pci_target_state(struct pci_dev *dev)
+{
+ pci_power_t target_state = PCI_D3hot;
- value &= PCI_PM_CAP_PME_MASK;
- value >>= ffs(PCI_PM_CAP_PME_MASK) - 1; /* First bit of mask */
+ if (platform_pci_power_manageable(dev)) {
+ /*
+ * Call the platform to choose the target state of the device
+ * and enable wake-up from this state if supported.
+ */
+ pci_power_t state = platform_pci_choose_state(dev);
- /* Check if it can generate PME# from requested state. */
- if (!value || !(value & (1 << state))) {
- /* if it can't, revert what the platform hook changed,
- * always reporting the base "EINVAL, can't PME#" error
+ switch (state) {
+ case PCI_POWER_ERROR:
+ case PCI_UNKNOWN:
+ break;
+ case PCI_D1:
+ case PCI_D2:
+ if (pci_no_d1d2(dev))
+ break;
+ default:
+ target_state = state;
+ }
+ } else if (device_may_wakeup(&dev->dev)) {
+ /*
+ * Find the deepest state from which the device can generate
+ * wake-up events, make it the target state and enable device
+ * to generate PME#.
*/
- if (enable)
- call_platform_enable_wakeup(&dev->dev, 0);
- return enable ? -EINVAL : 0;
+ if (!dev->pm_cap)
+ return PCI_POWER_ERROR;
+
+ if (dev->pme_support) {
+ while (target_state
+ && !(dev->pme_support & (1 << target_state)))
+ target_state--;
+ }
}
- pci_read_config_word(dev, pm + PCI_PM_CTRL, &value);
+ return target_state;
+}
- /* Clear PME_Status by writing 1 to it and enable PME# */
- value |= PCI_PM_CTRL_PME_STATUS | PCI_PM_CTRL_PME_ENABLE;
+/**
+ * pci_prepare_to_sleep - prepare PCI device for system-wide transition into a sleep state
+ * @dev: Device to handle.
+ *
+ * Choose the power state appropriate for the device depending on whether
+ * it can wake up the system and/or is power manageable by the platform
+ * (PCI_D3hot is the default) and put the device into that state.
+ */
+int pci_prepare_to_sleep(struct pci_dev *dev)
+{
+ pci_power_t target_state = pci_target_state(dev);
+ int error;
- if (!enable)
- value &= ~PCI_PM_CTRL_PME_ENABLE;
+ if (target_state == PCI_POWER_ERROR)
+ return -EIO;
- pci_write_config_word(dev, pm + PCI_PM_CTRL, value);
+ pci_enable_wake(dev, target_state, true);
- return 0;
+ error = pci_set_power_state(dev, target_state);
+
+ if (error)
+ pci_enable_wake(dev, target_state, false);
+
+ return error;
+}
+
+/**
+ * pci_back_from_sleep - turn PCI device on during system-wide transition into working state
+ * @dev: Device to handle.
+ *
+ * Disable device's sytem wake-up capability and put it into D0.
+ */
+int pci_back_from_sleep(struct pci_dev *dev)
+{
+ pci_enable_wake(dev, PCI_D0, false);
+ return pci_set_power_state(dev, PCI_D0);
+}
+
+/**
+ * pci_pm_init - Initialize PM functions of given PCI device
+ * @dev: PCI device to handle.
+ */
+void pci_pm_init(struct pci_dev *dev)
+{
+ int pm;
+ u16 pmc;
+
+ dev->pm_cap = 0;
+
+ /* find PCI PM capability in list */
+ pm = pci_find_capability(dev, PCI_CAP_ID_PM);
+ if (!pm)
+ return;
+ /* Check device's ability to generate PME# */
+ pci_read_config_word(dev, pm + PCI_PM_PMC, &pmc);
+
+ if ((pmc & PCI_PM_CAP_VER_MASK) > 3) {
+ dev_err(&dev->dev, "unsupported PM cap regs version (%u)\n",
+ pmc & PCI_PM_CAP_VER_MASK);
+ return;
+ }
+
+ dev->pm_cap = pm;
+
+ dev->d1_support = false;
+ dev->d2_support = false;
+ if (!pci_no_d1d2(dev)) {
+ if (pmc & PCI_PM_CAP_D1) {
+ dev_printk(KERN_DEBUG, &dev->dev, "supports D1\n");
+ dev->d1_support = true;
+ }
+ if (pmc & PCI_PM_CAP_D2) {
+ dev_printk(KERN_DEBUG, &dev->dev, "supports D2\n");
+ dev->d2_support = true;
+ }
+ }
+
+ pmc &= PCI_PM_CAP_PME_MASK;
+ if (pmc) {
+ dev_printk(KERN_INFO, &dev->dev,
+ "PME# supported from%s%s%s%s%s\n",
+ (pmc & PCI_PM_CAP_PME_D0) ? " D0" : "",
+ (pmc & PCI_PM_CAP_PME_D1) ? " D1" : "",
+ (pmc & PCI_PM_CAP_PME_D2) ? " D2" : "",
+ (pmc & PCI_PM_CAP_PME_D3) ? " D3hot" : "",
+ (pmc & PCI_PM_CAP_PME_D3cold) ? " D3cold" : "");
+ dev->pme_support = pmc >> PCI_PM_CAP_PME_SHIFT;
+ /*
+ * Make device's PM flags reflect the wake-up capability, but
+ * let the user space enable it to wake up the system as needed.
+ */
+ device_set_wakeup_capable(&dev->dev, true);
+ device_set_wakeup_enable(&dev->dev, false);
+ /* Disable the PME# generation functionality */
+ pci_pme_active(dev, false);
+ } else {
+ dev->pme_support = 0;
+ }
}
int
EXPORT_SYMBOL(pci_set_power_state);
EXPORT_SYMBOL(pci_save_state);
EXPORT_SYMBOL(pci_restore_state);
+EXPORT_SYMBOL(pci_pme_capable);
EXPORT_SYMBOL(pci_enable_wake);
+EXPORT_SYMBOL(pci_target_state);
+EXPORT_SYMBOL(pci_prepare_to_sleep);
+EXPORT_SYMBOL(pci_back_from_sleep);
EXPORT_SYMBOL_GPL(pci_set_pcie_reset_state);