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e1000e: fix force smbus during suspend flow

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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>
This commit is contained in:
Vitaly Lifshits 2024-07-09 13:31:22 -07:00 committed by Jakub Kicinski
parent 97a9063518
commit 76a0a3f9cc
1 changed files with 53 additions and 20 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

73
drivers/net/ethernet/intel/e1000e/ich8lan.c
View File

@ -1108,6 +1108,46 @@ static s32 e1000_platform_pm_pch_lpt(struct e1000_hw *hw, bool link)
return 0;
}
/**
* 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
@ -1165,6 +1205,14 @@ s32 e1000_enable_ulp_lpt_lp(struct e1000_hw *hw, bool to_sx)
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_hw *hw, bool to_sx)
}
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: