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PCI: aerdrv: introduce default_downstream_reset_link

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I noticed that when I inject a fatal error to an endpoint via
aer-inject, aer_root_reset() is called as reset_link for a
downstream port at upstream of the endpoint:

  pcieport 0000:00:06.0: AER: Uncorrected (Fatal) error received: id=5401
   :
  pcieport 0000:52:02.0: Root Port link has been reset

It externally appears to be working, but internally issues some
accesses to PCI_ERR_ROOT_COMMAND/STATUS registers that is for
root port so not available on downstream port.

This patch introduces default_downstream_reset_link that is
a version of aer_root_reset() with no accesses to root port's
register. It is used for downstream ports that has no reset_link
function its specific.

This patch also updates related description in pcieaer-howto.txt.
Some minor fixes are included.

Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Reviewed-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This commit is contained in:
Hidetoshi Seto
2010-04-15 13:21:27 +09:00
committed by Jesse Barnes
parent 517cae3829
commit 89713422a7
4 changed files with 71 additions and 46 deletions
Download Patch File Download Diff File Expand all files Collapse all files

23
drivers/pci/pcie/aer/aerdrv.c
View File

@@ -341,7 +341,6 @@ static int __devinit aer_probe(struct pcie_device *dev)
**/
static pci_ers_result_t aer_root_reset(struct pci_dev *dev)
{
u16 p2p_ctrl;
u32 reg32;
int pos;
@@ -352,27 +351,7 @@ static pci_ers_result_t aer_root_reset(struct pci_dev *dev)
reg32 &= ~ROOT_PORT_INTR_ON_MESG_MASK;
pci_write_config_dword(dev, pos + PCI_ERR_ROOT_COMMAND, reg32);
/* Assert Secondary Bus Reset */
pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &p2p_ctrl);
p2p_ctrl |= PCI_BRIDGE_CTL_BUS_RESET;
pci_write_config_word(dev, PCI_BRIDGE_CONTROL, p2p_ctrl);
/*
* we should send hot reset message for 2ms to allow it time to
* propogate to all downstream ports
*/
msleep(2);
/* De-assert Secondary Bus Reset */
p2p_ctrl &= ~PCI_BRIDGE_CTL_BUS_RESET;
pci_write_config_word(dev, PCI_BRIDGE_CONTROL, p2p_ctrl);
/*
* System software must wait for at least 100ms from the end
* of a reset of one or more device before it is permitted
* to issue Configuration Requests to those devices.
*/
msleep(200);
aer_do_secondary_bus_reset(dev);
dev_printk(KERN_DEBUG, &dev->dev, "Root Port link has been reset\n");
/* Clear Root Error Status */

1
drivers/pci/pcie/aer/aerdrv.h
View File

@@ -114,6 +114,7 @@ static inline pci_ers_result_t merge_result(enum pci_ers_result orig,
}
extern struct bus_type pcie_port_bus_type;
extern void aer_do_secondary_bus_reset(struct pci_dev *dev);
extern int aer_init(struct pcie_device *dev);
extern void aer_isr(struct work_struct *work);
extern void aer_print_error(struct pci_dev *dev, struct aer_err_info *info);

78
drivers/pci/pcie/aer/aerdrv_core.c
View File

@@ -373,6 +373,53 @@ static pci_ers_result_t broadcast_error_message(struct pci_dev *dev,
return result_data.result;
}
/**
* aer_do_secondary_bus_reset - perform secondary bus reset
* @dev: pointer to bridge's pci_dev data structure
*
* Invoked when performing link reset at Root Port or Downstream Port.
*/
void aer_do_secondary_bus_reset(struct pci_dev *dev)
{
u16 p2p_ctrl;
/* Assert Secondary Bus Reset */
pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &p2p_ctrl);
p2p_ctrl |= PCI_BRIDGE_CTL_BUS_RESET;
pci_write_config_word(dev, PCI_BRIDGE_CONTROL, p2p_ctrl);
/*
* we should send hot reset message for 2ms to allow it time to
* propagate to all downstream ports
*/
msleep(2);
/* De-assert Secondary Bus Reset */
p2p_ctrl &= ~PCI_BRIDGE_CTL_BUS_RESET;
pci_write_config_word(dev, PCI_BRIDGE_CONTROL, p2p_ctrl);
/*
* System software must wait for at least 100ms from the end
* of a reset of one or more device before it is permitted
* to issue Configuration Requests to those devices.
*/
msleep(200);
}
/**
* default_downstream_reset_link - default reset function for Downstream Port
* @dev: pointer to downstream port's pci_dev data structure
*
* Invoked when performing link reset at Downstream Port w/ no aer driver.
*/
static pci_ers_result_t default_downstream_reset_link(struct pci_dev *dev)
{
aer_do_secondary_bus_reset(dev);
dev_printk(KERN_DEBUG, &dev->dev,
"Downstream Port link has been reset\n");
return PCI_ERS_RESULT_RECOVERED;
}
static int find_aer_service_iter(struct device *device, void *data)
{
struct pcie_port_service_driver *service_driver, **drv;
@@ -406,31 +453,28 @@ static pci_ers_result_t reset_link(struct pcie_device *aerdev,
pci_ers_result_t status;
struct pcie_port_service_driver *driver;
if (dev->hdr_type & PCI_HEADER_TYPE_BRIDGE)
if (dev->hdr_type & PCI_HEADER_TYPE_BRIDGE) {
/* Reset this port for all subordinates */
udev = dev;
else
} else {
/* Reset the upstream component (likely downstream port) */
udev = dev->bus->self;
}
/* Use the aer driver of the component firstly */
driver = find_aer_service(udev);
/*
* If it hasn't the driver and is downstream port, use the root port's
*/
if (!driver || !driver->reset_link) {
if (udev->pcie_type == PCI_EXP_TYPE_DOWNSTREAM &&
aerdev->device.driver &&
to_service_driver(aerdev->device.driver)->reset_link) {
driver = to_service_driver(aerdev->device.driver);
} else {
dev_printk(KERN_DEBUG, &dev->dev,
"no link-reset support at upstream device %s\n",
pci_name(udev));
return PCI_ERS_RESULT_DISCONNECT;
}
if (driver && driver->reset_link) {
status = driver->reset_link(udev);
} else if (udev->pcie_type == PCI_EXP_TYPE_DOWNSTREAM) {
status = default_downstream_reset_link(udev);
} else {
dev_printk(KERN_DEBUG, &dev->dev,
"no link-reset support at upstream device %s\n",
pci_name(udev));
return PCI_ERS_RESULT_DISCONNECT;
}
status = driver->reset_link(udev);
if (status != PCI_ERS_RESULT_RECOVERED) {
dev_printk(KERN_DEBUG, &dev->dev,
"link reset at upstream device %s failed\n",