6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Vitaly Lifshits <vitaly.lifshits@xxxxxxxxx>
commit 76a0a3f9cc2fbd0e56671706bb74a9a988397898 upstream.
Commit 861e8086029e ("e1000e: move force SMBUS from enable ulp function
to avoid PHY loss issue") resolved a PHY access loss during suspend on
Meteor Lake consumer platforms, but it affected corporate systems
incorrectly.
A better fix, working for both consumer and corporate systems, was
proposed in commit bfd546a552e1 ("e1000e: move force SMBUS near the end
of enable_ulp function"). However, it introduced a regression on older
devices, such as [8086:15B8], [8086:15F9], [8086:15BE].
This patch aims to fix the secondary regression, by limiting the scope of
the changes to Meteor Lake platforms only.
Fixes: bfd546a552e1 ("e1000e: move force SMBUS near the end of enable_ulp function")
Reported-by: Todd Brandt <todd.e.brandt@xxxxxxxxx>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218940
Reported-by: Dieter Mummenschanz <dmummenschanz@xxxxxx>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218936
Signed-off-by: Vitaly Lifshits <vitaly.lifshits@xxxxxxxxx>
Tested-by: Mor Bar-Gabay <morx.bar.gabay@xxxxxxxxx> (A Contingent Worker at Intel)
Signed-off-by: Tony Nguyen <anthony.l.nguyen@xxxxxxxxx>
Reviewed-by: Simon Horman <horms@xxxxxxxxxx>
Link: https://patch.msgid.link/20240709203123.2103296-1-anthony.l.nguyen@xxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/ethernet/intel/e1000e/ich8lan.c | 73 ++++++++++++++++++++--------
1 file changed, 53 insertions(+), 20 deletions(-)
--- a/drivers/net/ethernet/intel/e1000e/ich8lan.c
+++ b/drivers/net/ethernet/intel/e1000e/ich8lan.c
@@ -1109,6 +1109,46 @@ static s32 e1000_platform_pm_pch_lpt(str
}
/**
+ * e1000e_force_smbus - Force interfaces to transition to SMBUS mode.
+ * @hw: pointer to the HW structure
+ *
+ * Force the MAC and the PHY to SMBUS mode. Assumes semaphore already
+ * acquired.
+ *
+ * Return: 0 on success, negative errno on failure.
+ **/
+static s32 e1000e_force_smbus(struct e1000_hw *hw)
+{
+ u16 smb_ctrl = 0;
+ u32 ctrl_ext;
+ s32 ret_val;
+
+ /* Switching PHY interface always returns MDI error
+ * so disable retry mechanism to avoid wasting time
+ */
+ e1000e_disable_phy_retry(hw);
+
+ /* Force SMBus mode in the PHY */
+ ret_val = e1000_read_phy_reg_hv_locked(hw, CV_SMB_CTRL, &smb_ctrl);
+ if (ret_val) {
+ e1000e_enable_phy_retry(hw);
+ return ret_val;
+ }
+
+ smb_ctrl |= CV_SMB_CTRL_FORCE_SMBUS;
+ e1000_write_phy_reg_hv_locked(hw, CV_SMB_CTRL, smb_ctrl);
+
+ e1000e_enable_phy_retry(hw);
+
+ /* Force SMBus mode in the MAC */
+ ctrl_ext = er32(CTRL_EXT);
+ ctrl_ext |= E1000_CTRL_EXT_FORCE_SMBUS;
+ ew32(CTRL_EXT, ctrl_ext);
+
+ return 0;
+}
+
+/**
* e1000_enable_ulp_lpt_lp - configure Ultra Low Power mode for LynxPoint-LP
* @hw: pointer to the HW structure
* @to_sx: boolean indicating a system power state transition to Sx
@@ -1165,6 +1205,14 @@ s32 e1000_enable_ulp_lpt_lp(struct e1000
if (ret_val)
goto out;
+ if (hw->mac.type != e1000_pch_mtp) {
+ ret_val = e1000e_force_smbus(hw);
+ if (ret_val) {
+ e_dbg("Failed to force SMBUS: %d\n", ret_val);
+ goto release;
+ }
+ }
+
/* Si workaround for ULP entry flow on i127/rev6 h/w. Enable
* LPLU and disable Gig speed when entering ULP
*/
@@ -1225,27 +1273,12 @@ s32 e1000_enable_ulp_lpt_lp(struct e1000
}
release:
- /* Switching PHY interface always returns MDI error
- * so disable retry mechanism to avoid wasting time
- */
- e1000e_disable_phy_retry(hw);
-
- /* Force SMBus mode in PHY */
- ret_val = e1000_read_phy_reg_hv_locked(hw, CV_SMB_CTRL, &phy_reg);
- if (ret_val) {
- e1000e_enable_phy_retry(hw);
- hw->phy.ops.release(hw);
- goto out;
+ if (hw->mac.type == e1000_pch_mtp) {
+ ret_val = e1000e_force_smbus(hw);
+ if (ret_val)
+ e_dbg("Failed to force SMBUS over MTL system: %d\n",
+ ret_val);
}
- phy_reg |= CV_SMB_CTRL_FORCE_SMBUS;
- e1000_write_phy_reg_hv_locked(hw, CV_SMB_CTRL, phy_reg);
-
- e1000e_enable_phy_retry(hw);
-
- /* Force SMBus mode in MAC */
- mac_reg = er32(CTRL_EXT);
- mac_reg |= E1000_CTRL_EXT_FORCE_SMBUS;
- ew32(CTRL_EXT, mac_reg);
hw->phy.ops.release(hw);
out:
