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path: root/drivers/pci/pci.c
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Diffstat (limited to 'drivers/pci/pci.c')
-rw-r--r--drivers/pci/pci.c134
1 files changed, 113 insertions, 21 deletions
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 1b34fc56067e..e74d75843047 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -15,6 +15,7 @@
#include <linux/pci.h>
#include <linux/module.h>
#include <linux/spinlock.h>
+#include <linux/string.h>
#include <asm/dma.h> /* isa_dma_bridge_buggy */
#include "pci.h"
@@ -222,6 +223,39 @@ pci_find_parent_resource(const struct pci_dev *dev, struct resource *res)
}
/**
+ * pci_restore_bars - restore a devices BAR values (e.g. after wake-up)
+ * @dev: PCI device to have its BARs restored
+ *
+ * Restore the BAR values for a given device, so as to make it
+ * accessible by its driver.
+ */
+void
+pci_restore_bars(struct pci_dev *dev)
+{
+ int i, numres;
+
+ switch (dev->hdr_type) {
+ case PCI_HEADER_TYPE_NORMAL:
+ numres = 6;
+ break;
+ case PCI_HEADER_TYPE_BRIDGE:
+ numres = 2;
+ break;
+ case PCI_HEADER_TYPE_CARDBUS:
+ numres = 1;
+ break;
+ default:
+ /* Should never get here, but just in case... */
+ return;
+ }
+
+ for (i = 0; i < numres; i ++)
+ pci_update_resource(dev, &dev->resource[i], i);
+}
+
+int (*platform_pci_set_power_state)(struct pci_dev *dev, pci_power_t t);
+
+/**
* pci_set_power_state - Set the power state of a PCI device
* @dev: PCI device to be suspended
* @state: PCI power state (D0, D1, D2, D3hot, D3cold) we're entering
@@ -235,11 +269,10 @@ pci_find_parent_resource(const struct pci_dev *dev, struct resource *res)
* -EIO if device does not support PCI PM.
* 0 if we can successfully change the power state.
*/
-int (*platform_pci_set_power_state)(struct pci_dev *dev, pci_power_t t);
int
pci_set_power_state(struct pci_dev *dev, pci_power_t state)
{
- int pm;
+ int pm, need_restore = 0;
u16 pmcsr, pmc;
/* bound the state we're entering */
@@ -263,7 +296,7 @@ pci_set_power_state(struct pci_dev *dev, pci_power_t state)
return -EIO;
pci_read_config_word(dev,pm + PCI_PM_PMC,&pmc);
- if ((pmc & PCI_PM_CAP_VER_MASK) > 2) {
+ if ((pmc & PCI_PM_CAP_VER_MASK) > 3) {
printk(KERN_DEBUG
"PCI: %s has unsupported PM cap regs version (%u)\n",
pci_name(dev), pmc & PCI_PM_CAP_VER_MASK);
@@ -271,23 +304,32 @@ pci_set_power_state(struct pci_dev *dev, pci_power_t state)
}
/* check if this device supports the desired state */
- if (state == PCI_D1 || state == PCI_D2) {
- if (state == PCI_D1 && !(pmc & PCI_PM_CAP_D1))
- return -EIO;
- else if (state == PCI_D2 && !(pmc & PCI_PM_CAP_D2))
- return -EIO;
- }
+ if (state == PCI_D1 && !(pmc & PCI_PM_CAP_D1))
+ return -EIO;
+ else if (state == PCI_D2 && !(pmc & PCI_PM_CAP_D2))
+ return -EIO;
- /* If we're in D3, force entire word to 0.
+ pci_read_config_word(dev, pm + 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
* sets PowerState to 0.
*/
- if (dev->current_state >= PCI_D3hot)
- pmcsr = 0;
- else {
- pci_read_config_word(dev, pm + PCI_PM_CTRL, &pmcsr);
+ switch (dev->current_state) {
+ case PCI_D0:
+ case PCI_D1:
+ case PCI_D2:
pmcsr &= ~PCI_PM_CTRL_STATE_MASK;
pmcsr |= state;
+ break;
+ case PCI_UNKNOWN: /* Boot-up */
+ if ((pmcsr & PCI_PM_CTRL_STATE_MASK) == PCI_D3hot
+ && !(pmcsr & PCI_PM_CTRL_NO_SOFT_RESET))
+ need_restore = 1;
+ /* Fall-through: force to D0 */
+ default:
+ pmcsr = 0;
+ break;
}
/* enter specified state */
@@ -308,6 +350,22 @@ pci_set_power_state(struct pci_dev *dev, pci_power_t state)
platform_pci_set_power_state(dev, state);
dev->current_state = state;
+
+ /* According to section 5.4.1 of the "PCI BUS POWER MANAGEMENT
+ * INTERFACE SPECIFICATION, REV. 1.2", a device transitioning
+ * from D3hot to D0 _may_ perform an internal reset, thereby
+ * going to "D0 Uninitialized" rather than "D0 Initialized".
+ * For example, at least some versions of the 3c905B and the
+ * 3c556B exhibit this behaviour.
+ *
+ * At least some laptop BIOSen (e.g. the Thinkpad T21) leave
+ * devices in a D3hot state at boot. Consequently, we need to
+ * restore at least the BARs so that the device will be
+ * accessible to its driver.
+ */
+ if (need_restore)
+ pci_restore_bars(dev);
+
return 0;
}
@@ -333,13 +391,17 @@ pci_power_t pci_choose_state(struct pci_dev *dev, pm_message_t state)
if (platform_pci_choose_state) {
ret = platform_pci_choose_state(dev, state);
if (ret >= 0)
- state = ret;
+ state.event = ret;
}
- switch (state) {
- case 0: return PCI_D0;
- case 3: return PCI_D3hot;
+
+ switch (state.event) {
+ case PM_EVENT_ON:
+ return PCI_D0;
+ case PM_EVENT_FREEZE:
+ case PM_EVENT_SUSPEND:
+ return PCI_D3hot;
default:
- printk("They asked me for state %d\n", state);
+ printk("They asked me for state %d\n", state.event);
BUG();
}
return PCI_D0;
@@ -390,8 +452,11 @@ pci_enable_device_bars(struct pci_dev *dev, int bars)
{
int err;
- pci_set_power_state(dev, PCI_D0);
- if ((err = pcibios_enable_device(dev, bars)) < 0)
+ err = pci_set_power_state(dev, PCI_D0);
+ if (err < 0 && err != -EIO)
+ return err;
+ err = pcibios_enable_device(dev, bars);
+ if (err < 0)
return err;
return 0;
}
@@ -743,6 +808,31 @@ pci_clear_mwi(struct pci_dev *dev)
}
}
+/**
+ * pci_intx - enables/disables PCI INTx for device dev
+ * @pdev: the PCI device to operate on
+ * @enable: boolean: whether to enable or disable PCI INTx
+ *
+ * Enables/disables PCI INTx for device dev
+ */
+void
+pci_intx(struct pci_dev *pdev, int enable)
+{
+ u16 pci_command, new;
+
+ pci_read_config_word(pdev, PCI_COMMAND, &pci_command);
+
+ if (enable) {
+ new = pci_command & ~PCI_COMMAND_INTX_DISABLE;
+ } else {
+ new = pci_command | PCI_COMMAND_INTX_DISABLE;
+ }
+
+ if (new != pci_command) {
+ pci_write_config_word(pdev, PCI_COMMAND, new);
+ }
+}
+
#ifndef HAVE_ARCH_PCI_SET_DMA_MASK
/*
* These can be overridden by arch-specific implementations
@@ -805,6 +895,7 @@ struct pci_dev *isa_bridge;
EXPORT_SYMBOL(isa_bridge);
#endif
+EXPORT_SYMBOL_GPL(pci_restore_bars);
EXPORT_SYMBOL(pci_enable_device_bars);
EXPORT_SYMBOL(pci_enable_device);
EXPORT_SYMBOL(pci_disable_device);
@@ -819,6 +910,7 @@ EXPORT_SYMBOL(pci_request_region);
EXPORT_SYMBOL(pci_set_master);
EXPORT_SYMBOL(pci_set_mwi);
EXPORT_SYMBOL(pci_clear_mwi);
+EXPORT_SYMBOL_GPL(pci_intx);
EXPORT_SYMBOL(pci_set_dma_mask);
EXPORT_SYMBOL(pci_set_consistent_dma_mask);
EXPORT_SYMBOL(pci_assign_resource);