From 8496e85c20e7836b3dec97780e40f420a3ae2801 Mon Sep 17 00:00:00 2001
From: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Date: Sun, 1 Dec 2013 02:34:37 +0100
Subject: [PATCH] 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: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
drivers/net/ethernet/broadcom/tg3.c | 26 +++++++++++++++++++-------
drivers/pci/pci.c | 8 ++++++++
include/linux/pci.h | 1 +
3 files changed, 28 insertions(+), 7 deletions(-)
diff --git a/drivers/net/ethernet/broadcom/tg3.c b/drivers/net/ethernet/broadcom/tg3.c
index 369b736dde05..472305cdff4f 100644
--- a/drivers/net/ethernet/broadcom/tg3.c
+++ b/drivers/net/ethernet/broadcom/tg3.c
@@ -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));
- tg3_power_down_prepare(tp);
-
- tg3_carrier_off(tp);
+ 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 @@ static int tg3_suspend(struct device *device)
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 @@ static int tg3_resume(struct device *device)
if (!err)
tg3_phy_start(tp);
+unlock:
+ rtnl_unlock();
return err;
}
#endif /* CONFIG_PM_SLEEP */
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 33120d156668..07369f32e8bb 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -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);
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 1084a15175e0..25a389566e47 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -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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