6.6-stable review patch. If anyone has any objections, please let me know.
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From: Vitaly Lifshits vitaly.lifshits@intel.com
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@intel.com Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218940 Reported-by: Dieter Mummenschanz dmummenschanz@web.de Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218936 Signed-off-by: Vitaly Lifshits vitaly.lifshits@intel.com Tested-by: Mor Bar-Gabay morx.bar.gabay@intel.com (A Contingent Worker at Intel) Signed-off-by: Tony Nguyen anthony.l.nguyen@intel.com Reviewed-by: Simon Horman horms@kernel.org Link: https://patch.msgid.link/20240709203123.2103296-1-anthony.l.nguyen@intel.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- 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: