We need a contract between the reset API users and the PCI core about the
types of reset that a user needs vs. what PCI core can do internally.
If a platform supports hotplug, we need to do hotplug reset as an example.
Expose the reset types to the drivers and try different reset types based
on the new reset_type parameter.
Most users are expected to use PCI_RESET_ANY, PCI_RESET_FUNC or
PCI_RESET_LINK parameters.
Fixes: 811c5cb37df4 ("PCI: Unify try slot and bus reset API")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=200985
Suggested-by: Alex Williamson <alex.williamson@xxxxxxxxxx>
Signed-off-by: Sinan Kaya <okaya@xxxxxxxxxx>
---
.../net/ethernet/cavium/liquidio/lio_main.c | 2 +-
drivers/pci/pci.c | 59 ++++++++++++-------
drivers/xen/xen-pciback/pci_stub.c | 6 +-
include/linux/pci.h | 13 +++-
4 files changed, 55 insertions(+), 25 deletions(-)
diff --git a/drivers/net/ethernet/cavium/liquidio/lio_main.c b/drivers/net/ethernet/cavium/liquidio/lio_main.c
index 6fb13fa73b27..0ff76722734d 100644
--- a/drivers/net/ethernet/cavium/liquidio/lio_main.c
+++ b/drivers/net/ethernet/cavium/liquidio/lio_main.c
@@ -989,7 +989,7 @@ static void octeon_pci_flr(struct octeon_device *oct)
pci_write_config_word(oct->pci_dev, PCI_COMMAND,
PCI_COMMAND_INTX_DISABLE);
- rc = __pci_reset_function_locked(oct->pci_dev);
+ rc = __pci_reset_function_locked(oct->pci_dev, PCI_RESET_ANY);
if (rc != 0)
dev_err(&oct->pci_dev->dev, "Error %d resetting PCI function %d\n",
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 30b260332a10..43a4b0969153 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -4672,6 +4672,7 @@ static void pci_dev_restore(struct pci_dev *dev)
* __pci_reset_function_locked - reset a PCI device function while holding
* the @dev mutex lock.
* @dev: PCI device to reset
+ * @reset_type: reset mask to try
*
* Some devices allow an individual function to be reset without affecting
* other functions in the same device. The PCI device must be responsive
@@ -4687,9 +4688,9 @@ static void pci_dev_restore(struct pci_dev *dev)
* Returns 0 if the device function was successfully reset or negative if the
* device doesn't support resetting a single function.
*/
-int __pci_reset_function_locked(struct pci_dev *dev)
+int __pci_reset_function_locked(struct pci_dev *dev, u32 reset_type)
{
- int rc;
+ int rc = 0;
might_sleep();
@@ -4701,24 +4702,42 @@ int __pci_reset_function_locked(struct pci_dev *dev)
* other error, we're also finished: this indicates that further
* reset mechanisms might be broken on the device.
*/
- rc = pci_dev_specific_reset(dev, 0);
- if (rc != -ENOTTY)
- return rc;
- if (pcie_has_flr(dev)) {
- rc = pcie_flr(dev);
+ if (reset_type & PCI_RESET_DEV_SPECIFIC) {
+ rc = pci_dev_specific_reset(dev, 0);
if (rc != -ENOTTY)
return rc;
}
- rc = pci_af_flr(dev, 0);
- if (rc != -ENOTTY)
- return rc;
- rc = pci_pm_reset(dev, 0);
- if (rc != -ENOTTY)
- return rc;
- rc = pci_dev_reset_slot_function(dev, 0);
- if (rc != -ENOTTY)
- return rc;
- return pci_parent_bus_reset(dev, 0);
+
+ if (reset_type & PCI_RESET_FLR) {
+ if (pcie_has_flr(dev)) {
+ rc = pcie_flr(dev);
+ if (rc != -ENOTTY)
+ return rc;
+ }
+ rc = pci_af_flr(dev, 0);
+ if (rc != -ENOTTY)
+ return rc;
+ }
+
+ if (reset_type & PCI_RESET_PM) {
+ rc = pci_pm_reset(dev, 0);
+ if (rc != -ENOTTY)
+ return rc;
+ }
+
+ if (reset_type & PCI_RESET_SLOT) {
+ rc = pci_dev_reset_slot_function(dev, 0);
+ if (rc != -ENOTTY)
+ return rc;
+ }
+
+ if (reset_type & PCI_RESET_BUS) {
+ rc = pci_parent_bus_reset(dev, 0);
+ if (rc != -ENOTTY)
+ return rc;
+ }
+
+ return rc;
}
EXPORT_SYMBOL_GPL(__pci_reset_function_locked);
@@ -4783,7 +4802,7 @@ int pci_reset_function(struct pci_dev *dev)
pci_dev_lock(dev);
pci_dev_save_and_disable(dev);
- rc = __pci_reset_function_locked(dev);
+ rc = __pci_reset_function_locked(dev, PCI_RESET_ANY);
pci_dev_restore(dev);
pci_dev_unlock(dev);
@@ -4818,7 +4837,7 @@ int pci_reset_function_locked(struct pci_dev *dev)
pci_dev_save_and_disable(dev);
- rc = __pci_reset_function_locked(dev);
+ rc = __pci_reset_function_locked(dev, PCI_RESET_ANY);
pci_dev_restore(dev);
@@ -4843,7 +4862,7 @@ int pci_try_reset_function(struct pci_dev *dev)
return -EAGAIN;
pci_dev_save_and_disable(dev);
- rc = __pci_reset_function_locked(dev);
+ rc = __pci_reset_function_locked(dev, PCI_RESET_ANY);
pci_dev_restore(dev);
pci_dev_unlock(dev);
diff --git a/drivers/xen/xen-pciback/pci_stub.c b/drivers/xen/xen-pciback/pci_stub.c
index 59661db144e5..6dfb805bcb19 100644
--- a/drivers/xen/xen-pciback/pci_stub.c
+++ b/drivers/xen/xen-pciback/pci_stub.c
@@ -105,7 +105,7 @@ static void pcistub_device_release(struct kref *kref)
/* Call the reset function which does not take lock as this
* is called from "unbind" which takes a device_lock mutex.
*/
- __pci_reset_function_locked(dev);
+ __pci_reset_function_locked(dev, PCI_RESET_ANY);
if (pci_load_and_free_saved_state(dev, &dev_data->pci_saved_state))
dev_info(&dev->dev, "Could not reload PCI state\n");
else
@@ -283,7 +283,7 @@ void pcistub_put_pci_dev(struct pci_dev *dev)
* (so it's ready for the next domain)
*/
device_lock_assert(&dev->dev);
- __pci_reset_function_locked(dev);
+ __pci_reset_function_locked(dev, PCI_RESET_ANY);
dev_data = pci_get_drvdata(dev);
ret = pci_load_saved_state(dev, dev_data->pci_saved_state);
@@ -417,7 +417,7 @@ static int pcistub_init_device(struct pci_dev *dev)
dev_err(&dev->dev, "Could not store PCI conf saved state!\n");
else {
dev_dbg(&dev->dev, "resetting (FLR, D3, etc) the device\n");
- __pci_reset_function_locked(dev);
+ __pci_reset_function_locked(dev, PCI_RESET_ANY);
pci_restore_state(dev);
}
/* Now disable the device (this also ensures some private device
diff --git a/include/linux/pci.h b/include/linux/pci.h
index e72ca8dd6241..6924d837c959 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -849,6 +849,17 @@ enum {
PCI_SCAN_ALL_PCIE_DEVS = 0x00000040, /* Scan all, not just dev 0 */
};
+#define PCI_RESET_DEV_SPECIFIC (1 << 0)
+#define PCI_RESET_FLR (1 << 1)
+#define PCI_RESET_PM (1 << 2)
+#define PCI_RESET_SLOT (1 << 3)
+#define PCI_RESET_BUS (1 << 4)
+
+#define PCI_RESET_ANY (~0)
+#define PCI_RESET_FUNC (PCI_RESET_DEV_SPECIFIC | \
+ PCI_RESET_FLR | PCI_RESET_PM)
+#define PCI_RESET_LINK (PCI_RESET_SLOT | PCI_RESET_BUS)
+
/* These external functions are only available when PCI support is enabled */
#ifdef CONFIG_PCI
@@ -1111,7 +1122,7 @@ u32 pcie_bandwidth_available(struct pci_dev *dev, struct pci_dev **limiting_dev,
void pcie_print_link_status(struct pci_dev *dev);
bool pcie_has_flr(struct pci_dev *dev);
int pcie_flr(struct pci_dev *dev);
-int __pci_reset_function_locked(struct pci_dev *dev);
+int __pci_reset_function_locked(struct pci_dev *dev, u32 reset_type);
int pci_reset_function(struct pci_dev *dev);
int pci_reset_function_locked(struct pci_dev *dev);
int pci_try_reset_function(struct pci_dev *dev);
--
2.18.0
