[PATCH 3/3][SRU][OEM-5.13][I][U] UBUNTU: SAUCE: e1000e: Additional PHY power saving in S0ix

[You-Sheng Yang]

From: Sasha Neftin <sasha.neftin at intel.com>

BugLink: https://bugs.launchpad.net/bugs/1937252

After transferring the MAC-PHY interface to the SMBus set the PHY
to S0ix low power idle mode.

Suggested-by: Dima Ruinskiy <dima.ruinskiy at intel.com>
Signed-off-by: Sasha Neftin <sasha.neftin at intel.com>
Tested-by: Dvora Fuxbrumer <dvorax.fuxbrumer at linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen at intel.com>
(cherry picked from
https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git/commit/?id=3ad3e28cb203309fb29022dea41cd65df0583632)
Signed-off-by: You-Sheng Yang <vicamo.yang at canonical.com>
---
 drivers/net/ethernet/intel/e1000e/netdev.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c
index 3ae6545de47c..35618ae7e016 100644
--- a/drivers/net/ethernet/intel/e1000e/netdev.c
+++ b/drivers/net/ethernet/intel/e1000e/netdev.c
@@ -6376,10 +6376,16 @@ static void e1000e_s0ix_entry_flow(struct e1000_adapter *adapter)
 		ew32(CTRL_EXT, mac_data);
 
 		/* DFT control: PHY bit: page769_20[0] = 1
+		 * page769_20[7] - PHY PLL stop
+		 * page769_20[8] - PHY go to the electrical idle
+		 * page769_20[9] - PHY serdes disable
 		 * Gate PPW via EXTCNF_CTRL - set 0x0F00[7] = 1
 		 */
 		e1e_rphy(hw, I82579_DFT_CTRL, &phy_data);
 		phy_data |= BIT(0);
+		phy_data |= BIT(7);
+		phy_data |= BIT(8);
+		phy_data |= BIT(9);
 		e1e_wphy(hw, I82579_DFT_CTRL, phy_data);
 
 		mac_data = er32(EXTCNF_CTRL);
-- 
2.32.0