Hi All

I resend my patch.
Sorry, my previous mail lacked an explanation.


The e1000 driver doesn't let the power down when running ifdown command.
So, I set to the D3hot state of a PCI device at the end of e1000_close().

With this modification, e1000 driver reduces power by ifdown.
It's about 6 watts when I measured a total power of one server machine
in my environment.

I tested this patch. The result is good enough to me.

Could you please check my patch ?
If I should have other considerations, please tell me.


Thanks you.
Naohiro Ooiwa



Signed-off-by: Naohiro Ooiwa <redacted>
---
 drivers/net/e1000/e1000_main.c |   32 ++++++++++++++++++++++++++++++++
 1 files changed, 32 insertions(+), 0 deletions(-)

diff --git a/drivers/net/e1000/e1000_main.c b/drivers/net/e1000/e1000_main.c
index bcd192c..12e1a42 100644
--- a/drivers/net/e1000/e1000_main.c
+++ b/drivers/net/e1000/e1000_main.c

@@ -26,6 +26,11 @@

 *******************************************************************************/

+/*
+ * define this if you want pci save power while ifdown.
+ */
+#define E1000_PCI_POWER_SAVE
+
 #include "e1000.h"
 #include <net/ip6_checksum.h>

@@ -1248,6 +1253,23 @@ static int e1000_open(struct net_device *netdev)

       struct e1000_hw *hw = &adapter->hw;
       int err;

+#ifdef E1000_PCI_POWER_SAVE
+       struct pci_dev *pdev = adapter->pdev;
+
+       pci_set_power_state(pdev, PCI_D0);
+       pci_restore_state(pdev);
+
+       if (adapter->need_ioport)
+               err = pci_enable_device(pdev);
+       else
+               err = pci_enable_device_mem(pdev);
+       if (err) {
+               printk(KERN_ERR "e1000: Cannot enable PCI device from power-save\n");
+               return err;
+       }
+       pci_set_master(pdev);
+#endif
+
       /* disallow open during test */
       if (test_bit(__E1000_TESTING, &adapter->flags))
               return -EBUSY;

@@ -1265,6 +1287,7 @@ static int e1000_open(struct net_device *netdev)

               goto err_setup_rx;

       e1000_power_up_phy(adapter);
+       e1000_reset(adapter);

       adapter->mng_vlan_id = E1000_MNG_VLAN_NONE;
       if ((hw->mng_cookie.status &

@@ -1341,6 +1364,15 @@ static int e1000_close(struct net_device *netdev)

               e1000_vlan_rx_kill_vid(netdev, adapter->mng_vlan_id);
       }

+#ifdef E1000_PCI_POWER_SAVE
+#ifdef CONFIG_PM
+       pci_save_state(adapter->pdev);
+#endif
+       pci_disable_device(adapter->pdev);
+       pci_wake_from_d3(adapter->pdev, true);
+       pci_set_power_state(adapter->pdev, PCI_D3hot);
+#endif
+
       return 0;
 }