From: Anatoly Burakov <anatoly.burakov@intel.com>
To: dev@dpdk.org
Subject: [PATCH v1 33/42] net/e1000/base: add PHY read/write retry mechanism
Date: Fri, 31 Jan 2025 12:58:46 +0000 [thread overview]
Message-ID: <73a542625a41775fe8a6e0c8eaa176e21f257cf8.1738328108.git.anatoly.burakov@intel.com> (raw)
In-Reply-To: <cover.1738328106.git.anatoly.burakov@intel.com>
From: Nir Efrati <nir.efrati@intel.com>
Sporadic MDI errors are observed on some platforms. To address them, a
read/write retry mechanism is introduced. Set the initial retry counter
to 3 with an option to disable/enable the mechanism for some specific
flows that errors are expected.
Signed-off-by: Nir Efrati <nir.efrati@intel.com>
Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
---
drivers/net/intel/e1000/base/e1000_hw.h | 1 +
drivers/net/intel/e1000/base/e1000_ich8lan.c | 34 ++++
drivers/net/intel/e1000/base/e1000_phy.c | 195 ++++++++++++-------
drivers/net/intel/e1000/base/e1000_phy.h | 2 +
4 files changed, 157 insertions(+), 75 deletions(-)
diff --git a/drivers/net/intel/e1000/base/e1000_hw.h b/drivers/net/intel/e1000/base/e1000_hw.h
index 2c425fd799..4fe38d0a68 100644
--- a/drivers/net/intel/e1000/base/e1000_hw.h
+++ b/drivers/net/intel/e1000/base/e1000_hw.h
@@ -879,6 +879,7 @@ struct e1000_phy_info {
u32 id;
u32 reset_delay_us; /* in usec */
u32 revision;
+ u32 current_retry_counter;
enum e1000_media_type media_type;
diff --git a/drivers/net/intel/e1000/base/e1000_ich8lan.c b/drivers/net/intel/e1000/base/e1000_ich8lan.c
index 01cda7ddeb..c3449a3f45 100644
--- a/drivers/net/intel/e1000/base/e1000_ich8lan.c
+++ b/drivers/net/intel/e1000/base/e1000_ich8lan.c
@@ -217,11 +217,19 @@ STATIC bool e1000_phy_is_accessible_pchlan(struct e1000_hw *hw)
/* Only unforce SMBus if ME is not active */
if (!(E1000_READ_REG(hw, E1000_FWSM) &
E1000_ICH_FWSM_FW_VALID)) {
+ /* Switching PHY interface always returns MDI error
+ * so disable retry mechanism to avoid wasting time
+ */
+ u32 phy_retries = 0;
+ e1000_disable_phy_retry_mechanism(hw, &phy_retries);
+
/* Unforce SMBus mode in PHY */
hw->phy.ops.read_reg_locked(hw, CV_SMB_CTRL, &phy_reg);
phy_reg &= ~CV_SMB_CTRL_FORCE_SMBUS;
hw->phy.ops.write_reg_locked(hw, CV_SMB_CTRL, phy_reg);
+ e1000_enable_phy_retry_mechanism(hw, phy_retries);
+
/* Unforce SMBus mode in MAC */
mac_reg = E1000_READ_REG(hw, E1000_CTRL_EXT);
mac_reg &= ~E1000_CTRL_EXT_FORCE_SMBUS;
@@ -287,6 +295,7 @@ STATIC s32 e1000_init_phy_workarounds_pchlan(struct e1000_hw *hw)
{
u32 mac_reg, fwsm = E1000_READ_REG(hw, E1000_FWSM);
s32 ret_val;
+ u32 phy_retries = 0;
DEBUGFUNC("e1000_init_phy_workarounds_pchlan");
@@ -306,6 +315,11 @@ STATIC s32 e1000_init_phy_workarounds_pchlan(struct e1000_hw *hw)
goto out;
}
+ /* There is no guarantee that the PHY is accessible at this time
+ * so disable retry mechanism to avoid wasting time
+ */
+ e1000_disable_phy_retry_mechanism(hw, &phy_retries);
+
/* 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.
@@ -374,6 +388,8 @@ STATIC s32 e1000_init_phy_workarounds_pchlan(struct e1000_hw *hw)
break;
}
+ e1000_enable_phy_retry_mechanism(hw, phy_retries);
+
hw->phy.ops.release(hw);
if (!ret_val) {
@@ -450,6 +466,8 @@ STATIC s32 e1000_init_phy_params_pchlan(struct e1000_hw *hw)
phy->id = e1000_phy_unknown;
+ if (hw->mac.type == e1000_pch_mtp)
+ phy->current_retry_counter = 2;
ret_val = e1000_init_phy_workarounds_pchlan(hw);
if (ret_val)
return ret_val;
@@ -1139,6 +1157,12 @@ s32 e1000_enable_ulp_lpt_lp(struct e1000_hw *hw, bool to_sx)
if (hw->dev_spec.ich8lan.smbus_disable)
goto skip_smbus;
+ /* Switching PHY interface always returns MDI error
+ * so disable retry mechanism to avoid wasting time
+ */
+ u32 phy_retries = 0;
+ e1000_disable_phy_retry_mechanism(hw, &phy_retries);
+
/* Force SMBus mode in PHY */
ret_val = e1000_read_phy_reg_hv_locked(hw, CV_SMB_CTRL, &phy_reg);
if (ret_val)
@@ -1146,6 +1170,8 @@ s32 e1000_enable_ulp_lpt_lp(struct e1000_hw *hw, bool to_sx)
phy_reg |= CV_SMB_CTRL_FORCE_SMBUS;
e1000_write_phy_reg_hv_locked(hw, CV_SMB_CTRL, phy_reg);
+ e1000_enable_phy_retry_mechanism(hw, phy_retries);
+
/* Force SMBus mode in MAC */
mac_reg = E1000_READ_REG(hw, E1000_CTRL_EXT);
mac_reg |= E1000_CTRL_EXT_FORCE_SMBUS;
@@ -1351,6 +1377,12 @@ s32 e1000_disable_ulp_lpt_lp(struct e1000_hw *hw, bool force)
/* 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
+ */
+ u32 phy_retries = 0;
+ e1000_disable_phy_retry_mechanism(hw, &phy_retries);
+
/* Unforce SMBus mode in PHY */
ret_val = e1000_read_phy_reg_hv_locked(hw, CV_SMB_CTRL, &phy_reg);
if (ret_val) {
@@ -1371,6 +1403,8 @@ s32 e1000_disable_ulp_lpt_lp(struct e1000_hw *hw, bool force)
phy_reg &= ~CV_SMB_CTRL_FORCE_SMBUS;
e1000_write_phy_reg_hv_locked(hw, CV_SMB_CTRL, phy_reg);
+ e1000_enable_phy_retry_mechanism(hw, phy_retries);
+
/* Unforce SMBus mode in MAC */
mac_reg = E1000_READ_REG(hw, E1000_CTRL_EXT);
mac_reg &= ~E1000_CTRL_EXT_FORCE_SMBUS;
diff --git a/drivers/net/intel/e1000/base/e1000_phy.c b/drivers/net/intel/e1000/base/e1000_phy.c
index 92c60aeb49..e9df7ec873 100644
--- a/drivers/net/intel/e1000/base/e1000_phy.c
+++ b/drivers/net/intel/e1000/base/e1000_phy.c
@@ -253,6 +253,22 @@ s32 e1000_phy_reset_dsp_generic(struct e1000_hw *hw)
return hw->phy.ops.write_reg(hw, M88E1000_PHY_GEN_CONTROL, 0);
}
+void e1000_disable_phy_retry_mechanism(struct e1000_hw* hw, u32* phy_retries_original)
+{
+ DEBUGFUNC("e1000_disable_phy_retry_mechanism");
+
+ *phy_retries_original = hw->phy.current_retry_counter;
+
+ hw->phy.current_retry_counter = 0;
+}
+
+void e1000_enable_phy_retry_mechanism(struct e1000_hw* hw, u32 phy_retries_original)
+{
+ DEBUGFUNC("e1000_enable_phy_retry_mechanism");
+
+ hw->phy.current_retry_counter = phy_retries_original;
+}
+
/**
* e1000_read_phy_reg_mdic - Read MDI control register
* @hw: pointer to the HW structure
@@ -265,7 +281,8 @@ s32 e1000_phy_reset_dsp_generic(struct e1000_hw *hw)
s32 e1000_read_phy_reg_mdic(struct e1000_hw *hw, u32 offset, u16 *data)
{
struct e1000_phy_info *phy = &hw->phy;
- u32 i, mdic = 0;
+ u32 i, mdic = 0, retry_counter;
+ bool success;
DEBUGFUNC("e1000_read_phy_reg_mdic");
@@ -278,45 +295,59 @@ s32 e1000_read_phy_reg_mdic(struct e1000_hw *hw, u32 offset, u16 *data)
* 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));
-
- E1000_WRITE_REG(hw, E1000_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++) {
- usec_delay_irq(50);
- mdic = E1000_READ_REG(hw, E1000_MDIC);
- if (mdic & E1000_MDIC_READY)
- break;
- }
- if (!(mdic & E1000_MDIC_READY)) {
- DEBUGOUT("MDI Read did not complete\n");
- return -E1000_ERR_PHY;
- }
- if (mdic & E1000_MDIC_ERROR) {
- DEBUGOUT("MDI Error\n");
- return -E1000_ERR_PHY;
- }
- if (((mdic & E1000_MDIC_REG_MASK) >> E1000_MDIC_REG_SHIFT) != offset) {
- DEBUGOUT2("MDI Read offset error - requested %d, returned %d\n",
- offset,
- (mdic & E1000_MDIC_REG_MASK) >> E1000_MDIC_REG_SHIFT);
- return -E1000_ERR_PHY;
+
+ for (retry_counter = 0; retry_counter <= hw->phy.current_retry_counter; retry_counter++) {
+ success = true;
+
+ mdic = ((offset << E1000_MDIC_REG_SHIFT) |
+ (phy->addr << E1000_MDIC_PHY_SHIFT) |
+ (E1000_MDIC_OP_READ));
+
+ E1000_WRITE_REG(hw, E1000_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++) {
+ usec_delay_irq(50);
+ mdic = E1000_READ_REG(hw, E1000_MDIC);
+ if (mdic & E1000_MDIC_READY)
+ break;
+ }
+ if (!(mdic & E1000_MDIC_READY)) {
+ DEBUGOUT("MDI Read did not complete\n");
+ success = false;
+ }
+ if (mdic & E1000_MDIC_ERROR) {
+ DEBUGOUT("MDI Error\n");
+ success = false;
+ }
+ if (((mdic & E1000_MDIC_REG_MASK) >> E1000_MDIC_REG_SHIFT) != offset) {
+ DEBUGOUT2("MDI Read offset error - requested %d, returned %d\n",
+ offset,
+ (mdic & E1000_MDIC_REG_MASK) >> E1000_MDIC_REG_SHIFT);
+ 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)
+ usec_delay_irq(100);
+
+ if (success) {
+ *data = (u16)mdic;
+ return E1000_SUCCESS;
+ }
+ if (retry_counter != hw->phy.current_retry_counter) {
+ DEBUGOUT("Perform retry on PHY transaction...\n");
+ msec_delay_irq(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)
- usec_delay_irq(100);
- return E1000_SUCCESS;
+ return -E1000_ERR_PHY;
}
/**
@@ -330,7 +361,8 @@ s32 e1000_read_phy_reg_mdic(struct e1000_hw *hw, u32 offset, u16 *data)
s32 e1000_write_phy_reg_mdic(struct e1000_hw *hw, u32 offset, u16 data)
{
struct e1000_phy_info *phy = &hw->phy;
- u32 i, mdic = 0;
+ u32 i, mdic = 0, retry_counter;
+ bool success;
DEBUGFUNC("e1000_write_phy_reg_mdic");
@@ -343,45 +375,58 @@ s32 e1000_write_phy_reg_mdic(struct e1000_hw *hw, u32 offset, u16 data)
* 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));
-
- E1000_WRITE_REG(hw, E1000_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++) {
- usec_delay_irq(50);
- mdic = E1000_READ_REG(hw, E1000_MDIC);
- if (mdic & E1000_MDIC_READY)
- break;
- }
- if (!(mdic & E1000_MDIC_READY)) {
- DEBUGOUT("MDI Write did not complete\n");
- return -E1000_ERR_PHY;
- }
- if (mdic & E1000_MDIC_ERROR) {
- DEBUGOUT("MDI Error\n");
- return -E1000_ERR_PHY;
- }
- if (((mdic & E1000_MDIC_REG_MASK) >> E1000_MDIC_REG_SHIFT) != offset) {
- DEBUGOUT2("MDI Write offset error - requested %d, returned %d\n",
- offset,
- (mdic & E1000_MDIC_REG_MASK) >> E1000_MDIC_REG_SHIFT);
- return -E1000_ERR_PHY;
- }
- /* Allow some time after each MDIC transaction to avoid
- * reading duplicate data in the next MDIC transaction.
- */
- if (hw->mac.type == e1000_pch2lan)
- usec_delay_irq(100);
+ for (retry_counter = 0; retry_counter <= hw->phy.current_retry_counter; retry_counter++) {
+ success = true;
+
+ mdic = (((u32)data) |
+ (offset << E1000_MDIC_REG_SHIFT) |
+ (phy->addr << E1000_MDIC_PHY_SHIFT) |
+ (E1000_MDIC_OP_WRITE));
+
+ E1000_WRITE_REG(hw, E1000_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++) {
+ usec_delay_irq(50);
+ mdic = E1000_READ_REG(hw, E1000_MDIC);
+ if (mdic & E1000_MDIC_READY)
+ break;
+ }
+ if (!(mdic & E1000_MDIC_READY)) {
+ DEBUGOUT("MDI Write did not complete\n");
+ success = false;
+ }
+ if (mdic & E1000_MDIC_ERROR) {
+ DEBUGOUT("MDI Error\n");
+ success = false;
+ }
+ if (((mdic & E1000_MDIC_REG_MASK) >> E1000_MDIC_REG_SHIFT) != offset) {
+ DEBUGOUT2("MDI Write offset error - requested %d, returned %d\n",
+ offset,
+ (mdic & E1000_MDIC_REG_MASK) >> E1000_MDIC_REG_SHIFT);
+ 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)
+ usec_delay_irq(100);
+
+ if (success)
+ return E1000_SUCCESS;
+
+ if (retry_counter != hw->phy.current_retry_counter) {
+ DEBUGOUT("Perform retry on PHY transaction...\n");
+ msec_delay_irq(10);
+ }
+ }
- return E1000_SUCCESS;
+ return -E1000_ERR_PHY;
}
/**
diff --git a/drivers/net/intel/e1000/base/e1000_phy.h b/drivers/net/intel/e1000/base/e1000_phy.h
index f15f45011f..4c0b93c18f 100644
--- a/drivers/net/intel/e1000/base/e1000_phy.h
+++ b/drivers/net/intel/e1000/base/e1000_phy.h
@@ -68,6 +68,8 @@ s32 e1000_read_phy_reg_bm2(struct e1000_hw *hw, u32 offset, u16 *data);
s32 e1000_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 e1000_disable_phy_retry_mechanism(struct e1000_hw *hw, u32 *phy_retries_original);
+void e1000_enable_phy_retry_mechanism(struct e1000_hw *hw, u32 phy_retries_original);
s32 e1000_read_phy_reg_mdic(struct e1000_hw *hw, u32 offset, u16 *data);
s32 e1000_write_phy_reg_mdic(struct e1000_hw *hw, u32 offset, u16 data);
s32 e1000_read_phy_reg_i2c(struct e1000_hw *hw, u32 offset, u16 *data);
--
2.43.5
next prev parent reply other threads:[~2025-01-31 13:03 UTC|newest]
Thread overview: 45+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-01-31 12:58 [PATCH v1 00/42] Merge Intel IGC and E1000 drivers, and update E1000 base code Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 01/42] net/e1000/base: fix semaphore timeout value Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 02/42] net/e1000/base: add initial support for i225 Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 03/42] net/e1000/base: add link bringup " Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 04/42] net/e1000/base: add LED blink " Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 05/42] net/e1000/base: add NVM/EEPROM " Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 06/42] net/e1000/base: add LTR support in i225 Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 07/42] net/e1000/base: add eee support for i225 Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 08/42] net/e1000/base: add misc definitions " Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 09/42] net/e1000: merge igc with e1000 Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 10/42] net/e1000: add missing i225 devices Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 11/42] net/e1000: add missing hardware support Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 12/42] net/e1000: add support for more I219 devices Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 13/42] net/e1000/base: correct minor formatting issues Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 14/42] net/e1000/base: correct mPHY access logic Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 15/42] net/e1000/base: skip MANC check for 82575 Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 16/42] net/e1000/base: correct disable k1 logic Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 17/42] net/e1000/base: workaround for packet loss Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 18/42] net/e1000/base: add EEE common API function Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 19/42] net/e1000/base: add queue select definitions Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 20/42] net/e1000/base: add profile information field Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 21/42] net/e1000/base: add LPI counters Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 22/42] net/e1000/base: improve code flow in ICH8LAN Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 23/42] net/e1000/base: add definition for EXFWSM register Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 24/42] net/e1000/base: use longer ULP exit timeout on more HW Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 25/42] net/e1000/base: make e1000_access_phy_wakeup_reg_bm non-static Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 26/42] net/e1000/base: make debug prints more informative Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 27/42] net/e1000/base: add WoL definitions Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 28/42] net/e1000/base: hardcode bus parameters for ICH8 Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 29/42] net/e1000/base: improve NVM checksum handling Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 30/42] net/e1000/base: remove redundant access to RO register Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 31/42] net/e1000/base: remove non-inclusive language Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 32/42] net/e1000/base: introduce PHY ID retry mechanism Anatoly Burakov
2025-01-31 12:58 ` Anatoly Burakov [this message]
2025-01-31 12:58 ` [PATCH v1 34/42] net/e1000/base: fix iterator type Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 35/42] net/e1000/base: fix static analysis warnings Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 36/42] net/e1000/base: fix reset for 82580 Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 37/42] net/e1000/base: fix mac addr hash bit_shift Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 38/42] net/e1000/base: fix uninitialized variable usage Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 39/42] net/e1000/base: fix unchecked return Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 40/42] net/e1000/base: fix data type in MAC hash Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 41/42] net/e1000/base: rename NVM version variable Anatoly Burakov
2025-01-31 12:58 ` [PATCH v1 42/42] net/e1000/base: update readme Anatoly Burakov
2025-01-31 13:11 ` [PATCH v1 00/42] Merge Intel IGC and E1000 drivers, and update E1000 base code Bruce Richardson
2025-01-31 13:13 ` David Marchand
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