From: Chen Yu <yu.c.chen@intel.com>
Date: Tue, 8 Mar 2022 09:20:30 -0800
Subject: e1000e: Print PHY register address when MDI read/write fails
Patch-mainline: v5.18-rc1
Git-commit: 91ec77924714b67a6fbe9f6631dd639012fb76eb
References: jsc#PED-837

There is occasional suspend error from e1000e which blocks the
system from further suspending. And the issue was found on
a WhiskeyLake-U platform with I219-V:

[   20.078957] PM: pci_pm_suspend(): e1000e_pm_suspend+0x0/0x780 [e1000e] returns -2
[   20.078970] PM: dpm_run_callback(): pci_pm_suspend+0x0/0x170 returns -2
[   20.078974] e1000e 0000:00:1f.6: PM: pci_pm_suspend+0x0/0x170 returned -2 after 371012 usecs
[   20.078978] e1000e 0000:00:1f.6: PM: failed to suspend async: error -2

According to the code flow, this might be caused by broken MDI read/write
to PHY registers. However currently the code does not tell us which
register is broken. Thus enhance the debug information to print the
offender PHY register. So the next the issue is reproduced, this
information could be used for narrow down.

Acked-by: Paul Menzel <pmenzel@molgen.mpg.de>
Reported-by: Todd Brandt <todd.e.brandt@intel.com>
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Tested-by: Naama Meir <naamax.meir@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Link: https://lore.kernel.org/r/20220308172030.451566-1-anthony.l.nguyen@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/intel/e1000e/phy.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

--- a/drivers/net/ethernet/intel/e1000e/phy.c
+++ b/drivers/net/ethernet/intel/e1000e/phy.c
@@ -146,11 +146,11 @@ s32 e1000e_read_phy_reg_mdic(struct e100
 			break;
 	}
 	if (!(mdic & E1000_MDIC_READY)) {
-		e_dbg("MDI Read did not complete\n");
+		e_dbg("MDI Read PHY Reg Address %d did not complete\n", offset);
 		return -E1000_ERR_PHY;
 	}
 	if (mdic & E1000_MDIC_ERROR) {
-		e_dbg("MDI Error\n");
+		e_dbg("MDI Read PHY Reg Address %d Error\n", offset);
 		return -E1000_ERR_PHY;
 	}
 	if (((mdic & E1000_MDIC_REG_MASK) >> E1000_MDIC_REG_SHIFT) != offset) {
@@ -210,11 +210,11 @@ s32 e1000e_write_phy_reg_mdic(struct e10
 			break;
 	}
 	if (!(mdic & E1000_MDIC_READY)) {
-		e_dbg("MDI Write did not complete\n");
+		e_dbg("MDI Write PHY Reg Address %d did not complete\n", offset);
 		return -E1000_ERR_PHY;
 	}
 	if (mdic & E1000_MDIC_ERROR) {
-		e_dbg("MDI Error\n");
+		e_dbg("MDI Write PHY Red Address %d Error\n", offset);
 		return -E1000_ERR_PHY;
 	}
 	if (((mdic & E1000_MDIC_REG_MASK) >> E1000_MDIC_REG_SHIFT) != offset) {