Commit 8496e85c authored by Rafael J. Wysocki's avatar Rafael J. Wysocki Committed by David S. Miller
Browse files

PCI / tg3: Give up chip reset and carrier loss handling if PCI device is not present 



Modify tg3_chip_reset() and tg3_close() to check if the PCI network
adapter device is accessible at all in order to skip poking it or
trying to handle a carrier loss in vain when that's not the case.
Introduce a special PCI helper function pci_device_is_present()
for this purpose.

Of course, this uncovers the lack of the appropriate RTNL locking
in tg3_suspend() and tg3_resume(), so add that locking in there
too.

These changes prevent tg3 from burning a CPU at 100% load level for
solid several seconds after the Thunderbolt link is disconnected from
a Matrox DS1 docking station.

Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: default avatarMichael Chan <mchan@broadcom.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 30e56918

drivers/net/ethernet/broadcom/tg3.c

+19 −7
Original line number Diff line number Diff line
@@ -8932,6 +8932,9 @@ static int tg3_chip_reset(struct tg3 *tp) 
	void (*write_op)(struct tg3 *, u32, u32);

	int i, err;



	if (!pci_device_is_present(tp->pdev))

		return -ENODEV;



	tg3_nvram_lock(tp);



	tg3_ape_lock(tp, TG3_APE_LOCK_GRC);
@@ -11581,10 +11584,11 @@ static int tg3_close(struct net_device *dev) 
	memset(&tp->net_stats_prev, 0, sizeof(tp->net_stats_prev));

	memset(&tp->estats_prev, 0, sizeof(tp->estats_prev));



	if (pci_device_is_present(tp->pdev)) {

		tg3_power_down_prepare(tp);



		tg3_carrier_off(tp);



	}

	return 0;

}
@@ -17726,10 +17730,12 @@ static int tg3_suspend(struct device *device) 
	struct pci_dev *pdev = to_pci_dev(device);

	struct net_device *dev = pci_get_drvdata(pdev);

	struct tg3 *tp = netdev_priv(dev);

	int err;

	int err = 0;



	rtnl_lock();



	if (!netif_running(dev))

		return 0;

		goto unlock;



	tg3_reset_task_cancel(tp);

	tg3_phy_stop(tp);
@@ -17771,6 +17777,8 @@ out: 
			tg3_phy_start(tp);

	}



unlock:

	rtnl_unlock();

	return err;

}
@@ -17779,10 +17787,12 @@ static int tg3_resume(struct device *device) 
	struct pci_dev *pdev = to_pci_dev(device);

	struct net_device *dev = pci_get_drvdata(pdev);

	struct tg3 *tp = netdev_priv(dev);

	int err;

	int err = 0;



	rtnl_lock();



	if (!netif_running(dev))

		return 0;

		goto unlock;



	netif_device_attach(dev);
@@ -17806,6 +17816,8 @@ out: 
	if (!err)

		tg3_phy_start(tp);



unlock:

	rtnl_unlock();

	return err;

}

#endif /* CONFIG_PM_SLEEP */

drivers/pci/pci.c

+8 −0
Original line number Diff line number Diff line
@@ -4165,6 +4165,14 @@ int pci_set_vga_state(struct pci_dev *dev, bool decode, 
	return 0;

}



bool pci_device_is_present(struct pci_dev *pdev)

{

	u32 v;



	return pci_bus_read_dev_vendor_id(pdev->bus, pdev->devfn, &v, 0);

}

EXPORT_SYMBOL_GPL(pci_device_is_present);



#define RESOURCE_ALIGNMENT_PARAM_SIZE COMMAND_LINE_SIZE

static char resource_alignment_param[RESOURCE_ALIGNMENT_PARAM_SIZE] = {0};

static DEFINE_SPINLOCK(resource_alignment_lock);

include/linux/pci.h

+1 −0
Original line number Diff line number Diff line
@@ -960,6 +960,7 @@ void pci_update_resource(struct pci_dev *dev, int resno); 
int __must_check pci_assign_resource(struct pci_dev *dev, int i);

int __must_check pci_reassign_resource(struct pci_dev *dev, int i, resource_size_t add_size, resource_size_t align);

int pci_select_bars(struct pci_dev *dev, unsigned long flags);

bool pci_device_is_present(struct pci_dev *pdev);



/* ROM control related routines */

int pci_enable_rom(struct pci_dev *pdev);

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