This is a note to let you know that I've just added the patch titled
e1000e: Workaround for sporadic MDI error on Meteor Lake systems
to the 6.8-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
e1000e-workaround-for-sporadic-mdi-error-on-meteor-lake-systems.patch
and it can be found in the queue-6.8 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 6dbdd4de0362c37e54e8b049781402e5a409e7d0 Mon Sep 17 00:00:00 2001
From: Vitaly Lifshits <vitaly.lifshits@xxxxxxxxx>
Date: Thu, 4 Jan 2024 16:16:52 +0200
Subject: e1000e: Workaround for sporadic MDI error on Meteor Lake systems
From: Vitaly Lifshits <vitaly.lifshits@xxxxxxxxx>
commit 6dbdd4de0362c37e54e8b049781402e5a409e7d0 upstream.
On some Meteor Lake systems accessing the PHY via the MDIO interface may
result in an MDI error. This issue happens sporadically and in most cases
a second access to the PHY via the MDIO interface results in success.
As a workaround, introduce a retry counter which is set to 3 on Meteor
Lake systems. The driver will only return an error if 3 consecutive PHY
access attempts fail. The retry mechanism is disabled in specific flows,
where MDI errors are expected.
Fixes: cc23f4f0b6b9 ("e1000e: Add support for Meteor Lake")
Suggested-by: Nikolay Mushayev <nikolay.mushayev@xxxxxxxxx>
Co-developed-by: Nir Efrati <nir.efrati@xxxxxxxxx>
Signed-off-by: Nir Efrati <nir.efrati@xxxxxxxxx>
Signed-off-by: Vitaly Lifshits <vitaly.lifshits@xxxxxxxxx>
Tested-by: Naama Meir <naamax.meir@xxxxxxxxxxxxxxx>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/ethernet/intel/e1000e/hw.h | 2
drivers/net/ethernet/intel/e1000e/ich8lan.c | 33 ++++
drivers/net/ethernet/intel/e1000e/phy.c | 190 +++++++++++++++++-----------
drivers/net/ethernet/intel/e1000e/phy.h | 2
4 files changed, 154 insertions(+), 73 deletions(-)
--- a/drivers/net/ethernet/intel/e1000e/hw.h
+++ b/drivers/net/ethernet/intel/e1000e/hw.h
@@ -628,6 +628,7 @@ struct e1000_phy_info {
u32 id;
u32 reset_delay_us; /* in usec */
u32 revision;
+ u32 retry_count;
enum e1000_media_type media_type;
@@ -644,6 +645,7 @@ struct e1000_phy_info {
bool polarity_correction;
bool speed_downgraded;
bool autoneg_wait_to_complete;
+ bool retry_enabled;
};
struct e1000_nvm_info {
--- a/drivers/net/ethernet/intel/e1000e/ich8lan.c
+++ b/drivers/net/ethernet/intel/e1000e/ich8lan.c
@@ -222,11 +222,18 @@ out:
if (hw->mac.type >= e1000_pch_lpt) {
/* Only unforce SMBus if ME is not active */
if (!(er32(FWSM) & E1000_ICH_FWSM_FW_VALID)) {
+ /* Switching PHY interface always returns MDI error
+ * so disable retry mechanism to avoid wasting time
+ */
+ e1000e_disable_phy_retry(hw);
+
/* Unforce SMBus mode in PHY */
e1e_rphy_locked(hw, CV_SMB_CTRL, &phy_reg);
phy_reg &= ~CV_SMB_CTRL_FORCE_SMBUS;
e1e_wphy_locked(hw, CV_SMB_CTRL, phy_reg);
+ e1000e_enable_phy_retry(hw);
+
/* Unforce SMBus mode in MAC */
mac_reg = er32(CTRL_EXT);
mac_reg &= ~E1000_CTRL_EXT_FORCE_SMBUS;
@@ -310,6 +317,11 @@ static s32 e1000_init_phy_workarounds_pc
goto out;
}
+ /* There is no guarantee that the PHY is accessible at this time
+ * so disable retry mechanism to avoid wasting time
+ */
+ e1000e_disable_phy_retry(hw);
+
/* The MAC-PHY interconnect may be in SMBus mode. If the PHY is
* inaccessible and resetting the PHY is not blocked, toggle the
* LANPHYPC Value bit to force the interconnect to PCIe mode.
@@ -380,6 +392,8 @@ static s32 e1000_init_phy_workarounds_pc
break;
}
+ e1000e_enable_phy_retry(hw);
+
hw->phy.ops.release(hw);
if (!ret_val) {
@@ -449,6 +463,11 @@ static s32 e1000_init_phy_params_pchlan(
phy->id = e1000_phy_unknown;
+ if (hw->mac.type == e1000_pch_mtp) {
+ phy->retry_count = 2;
+ e1000e_enable_phy_retry(hw);
+ }
+
ret_val = e1000_init_phy_workarounds_pchlan(hw);
if (ret_val)
return ret_val;
@@ -1146,6 +1165,11 @@ s32 e1000_enable_ulp_lpt_lp(struct e1000
if (ret_val)
goto out;
+ /* 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)
@@ -1153,6 +1177,8 @@ s32 e1000_enable_ulp_lpt_lp(struct e1000
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;
@@ -1313,6 +1339,11 @@ static s32 e1000_disable_ulp_lpt_lp(stru
/* Toggle LANPHYPC Value bit */
e1000_toggle_lanphypc_pch_lpt(hw);
+ /* Switching PHY interface always returns MDI error
+ * so disable retry mechanism to avoid wasting time
+ */
+ e1000e_disable_phy_retry(hw);
+
/* Unforce SMBus mode in PHY */
ret_val = e1000_read_phy_reg_hv_locked(hw, CV_SMB_CTRL, &phy_reg);
if (ret_val) {
@@ -1333,6 +1364,8 @@ static s32 e1000_disable_ulp_lpt_lp(stru
phy_reg &= ~CV_SMB_CTRL_FORCE_SMBUS;
e1000_write_phy_reg_hv_locked(hw, CV_SMB_CTRL, phy_reg);
+ e1000e_enable_phy_retry(hw);
+
/* Unforce SMBus mode in MAC */
mac_reg = er32(CTRL_EXT);
mac_reg &= ~E1000_CTRL_EXT_FORCE_SMBUS;
--- a/drivers/net/ethernet/intel/e1000e/phy.c
+++ b/drivers/net/ethernet/intel/e1000e/phy.c
@@ -107,6 +107,16 @@ s32 e1000e_phy_reset_dsp(struct e1000_hw
return e1e_wphy(hw, M88E1000_PHY_GEN_CONTROL, 0);
}
+void e1000e_disable_phy_retry(struct e1000_hw *hw)
+{
+ hw->phy.retry_enabled = false;
+}
+
+void e1000e_enable_phy_retry(struct e1000_hw *hw)
+{
+ hw->phy.retry_enabled = true;
+}
+
/**
* e1000e_read_phy_reg_mdic - Read MDI control register
* @hw: pointer to the HW structure
@@ -118,55 +128,73 @@ s32 e1000e_phy_reset_dsp(struct e1000_hw
**/
s32 e1000e_read_phy_reg_mdic(struct e1000_hw *hw, u32 offset, u16 *data)
{
+ u32 i, mdic = 0, retry_counter, retry_max;
struct e1000_phy_info *phy = &hw->phy;
- u32 i, mdic = 0;
+ bool success;
if (offset > MAX_PHY_REG_ADDRESS) {
e_dbg("PHY Address %d is out of range\n", offset);
return -E1000_ERR_PARAM;
}
+ retry_max = phy->retry_enabled ? phy->retry_count : 0;
+
/* Set up Op-code, Phy Address, and register offset in the MDI
* Control register. The MAC will take care of interfacing with the
* PHY to retrieve the desired data.
*/
- mdic = ((offset << E1000_MDIC_REG_SHIFT) |
- (phy->addr << E1000_MDIC_PHY_SHIFT) |
- (E1000_MDIC_OP_READ));
-
- ew32(MDIC, mdic);
-
- /* Poll the ready bit to see if the MDI read completed
- * Increasing the time out as testing showed failures with
- * the lower time out
- */
- for (i = 0; i < (E1000_GEN_POLL_TIMEOUT * 3); i++) {
- udelay(50);
- mdic = er32(MDIC);
- if (mdic & E1000_MDIC_READY)
- break;
- }
- if (!(mdic & E1000_MDIC_READY)) {
- 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 Read PHY Reg Address %d Error\n", offset);
- return -E1000_ERR_PHY;
- }
- if (FIELD_GET(E1000_MDIC_REG_MASK, mdic) != offset) {
- e_dbg("MDI Read offset error - requested %d, returned %d\n",
- offset, FIELD_GET(E1000_MDIC_REG_MASK, mdic));
- return -E1000_ERR_PHY;
+ for (retry_counter = 0; retry_counter <= retry_max; retry_counter++) {
+ success = true;
+
+ mdic = ((offset << E1000_MDIC_REG_SHIFT) |
+ (phy->addr << E1000_MDIC_PHY_SHIFT) |
+ (E1000_MDIC_OP_READ));
+
+ ew32(MDIC, mdic);
+
+ /* Poll the ready bit to see if the MDI read completed
+ * Increasing the time out as testing showed failures with
+ * the lower time out
+ */
+ for (i = 0; i < (E1000_GEN_POLL_TIMEOUT * 3); i++) {
+ usleep_range(50, 60);
+ mdic = er32(MDIC);
+ if (mdic & E1000_MDIC_READY)
+ break;
+ }
+ if (!(mdic & E1000_MDIC_READY)) {
+ e_dbg("MDI Read PHY Reg Address %d did not complete\n",
+ offset);
+ success = false;
+ }
+ if (mdic & E1000_MDIC_ERROR) {
+ e_dbg("MDI Read PHY Reg Address %d Error\n", offset);
+ success = false;
+ }
+ if (FIELD_GET(E1000_MDIC_REG_MASK, mdic) != offset) {
+ e_dbg("MDI Read offset error - requested %d, returned %d\n",
+ offset, FIELD_GET(E1000_MDIC_REG_MASK, mdic));
+ success = false;
+ }
+
+ /* Allow some time after each MDIC transaction to avoid
+ * reading duplicate data in the next MDIC transaction.
+ */
+ if (hw->mac.type == e1000_pch2lan)
+ usleep_range(100, 150);
+
+ if (success) {
+ *data = (u16)mdic;
+ return 0;
+ }
+
+ if (retry_counter != retry_max) {
+ e_dbg("Perform retry on PHY transaction...\n");
+ mdelay(10);
+ }
}
- *data = (u16)mdic;
- /* Allow some time after each MDIC transaction to avoid
- * reading duplicate data in the next MDIC transaction.
- */
- if (hw->mac.type == e1000_pch2lan)
- udelay(100);
- return 0;
+ return -E1000_ERR_PHY;
}
/**
@@ -179,56 +207,72 @@ s32 e1000e_read_phy_reg_mdic(struct e100
**/
s32 e1000e_write_phy_reg_mdic(struct e1000_hw *hw, u32 offset, u16 data)
{
+ u32 i, mdic = 0, retry_counter, retry_max;
struct e1000_phy_info *phy = &hw->phy;
- u32 i, mdic = 0;
+ bool success;
if (offset > MAX_PHY_REG_ADDRESS) {
e_dbg("PHY Address %d is out of range\n", offset);
return -E1000_ERR_PARAM;
}
+ retry_max = phy->retry_enabled ? phy->retry_count : 0;
+
/* Set up Op-code, Phy Address, and register offset in the MDI
* Control register. The MAC will take care of interfacing with the
* PHY to retrieve the desired data.
*/
- mdic = (((u32)data) |
- (offset << E1000_MDIC_REG_SHIFT) |
- (phy->addr << E1000_MDIC_PHY_SHIFT) |
- (E1000_MDIC_OP_WRITE));
-
- ew32(MDIC, mdic);
-
- /* Poll the ready bit to see if the MDI read completed
- * Increasing the time out as testing showed failures with
- * the lower time out
- */
- for (i = 0; i < (E1000_GEN_POLL_TIMEOUT * 3); i++) {
- udelay(50);
- mdic = er32(MDIC);
- if (mdic & E1000_MDIC_READY)
- break;
- }
- if (!(mdic & E1000_MDIC_READY)) {
- 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 Write PHY Red Address %d Error\n", offset);
- return -E1000_ERR_PHY;
- }
- if (FIELD_GET(E1000_MDIC_REG_MASK, mdic) != offset) {
- e_dbg("MDI Write offset error - requested %d, returned %d\n",
- offset, FIELD_GET(E1000_MDIC_REG_MASK, mdic));
- return -E1000_ERR_PHY;
- }
+ for (retry_counter = 0; retry_counter <= retry_max; retry_counter++) {
+ success = true;
- /* Allow some time after each MDIC transaction to avoid
- * reading duplicate data in the next MDIC transaction.
- */
- if (hw->mac.type == e1000_pch2lan)
- udelay(100);
+ mdic = (((u32)data) |
+ (offset << E1000_MDIC_REG_SHIFT) |
+ (phy->addr << E1000_MDIC_PHY_SHIFT) |
+ (E1000_MDIC_OP_WRITE));
+
+ ew32(MDIC, mdic);
+
+ /* Poll the ready bit to see if the MDI read completed
+ * Increasing the time out as testing showed failures with
+ * the lower time out
+ */
+ for (i = 0; i < (E1000_GEN_POLL_TIMEOUT * 3); i++) {
+ usleep_range(50, 60);
+ mdic = er32(MDIC);
+ if (mdic & E1000_MDIC_READY)
+ break;
+ }
+ if (!(mdic & E1000_MDIC_READY)) {
+ e_dbg("MDI Write PHY Reg Address %d did not complete\n",
+ offset);
+ success = false;
+ }
+ if (mdic & E1000_MDIC_ERROR) {
+ e_dbg("MDI Write PHY Reg Address %d Error\n", offset);
+ success = false;
+ }
+ if (FIELD_GET(E1000_MDIC_REG_MASK, mdic) != offset) {
+ e_dbg("MDI Write offset error - requested %d, returned %d\n",
+ offset, FIELD_GET(E1000_MDIC_REG_MASK, mdic));
+ success = false;
+ }
+
+ /* Allow some time after each MDIC transaction to avoid
+ * reading duplicate data in the next MDIC transaction.
+ */
+ if (hw->mac.type == e1000_pch2lan)
+ usleep_range(100, 150);
+
+ if (success)
+ return 0;
+
+ if (retry_counter != retry_max) {
+ e_dbg("Perform retry on PHY transaction...\n");
+ mdelay(10);
+ }
+ }
- return 0;
+ return -E1000_ERR_PHY;
}
/**
--- a/drivers/net/ethernet/intel/e1000e/phy.h
+++ b/drivers/net/ethernet/intel/e1000e/phy.h
@@ -51,6 +51,8 @@ s32 e1000e_read_phy_reg_bm2(struct e1000
s32 e1000e_write_phy_reg_bm2(struct e1000_hw *hw, u32 offset, u16 data);
void e1000_power_up_phy_copper(struct e1000_hw *hw);
void e1000_power_down_phy_copper(struct e1000_hw *hw);
+void e1000e_disable_phy_retry(struct e1000_hw *hw);
+void e1000e_enable_phy_retry(struct e1000_hw *hw);
s32 e1000e_read_phy_reg_mdic(struct e1000_hw *hw, u32 offset, u16 *data);
s32 e1000e_write_phy_reg_mdic(struct e1000_hw *hw, u32 offset, u16 data);
s32 e1000_read_phy_reg_hv(struct e1000_hw *hw, u32 offset, u16 *data);
Patches currently in stable-queue which might be from vitaly.lifshits@xxxxxxxxx are
queue-6.8/e1000e-workaround-for-sporadic-mdi-error-on-meteor-lake-systems.patch
