When booting with a dock connected, the igc driver may get stuck for ~40
seconds if PCIe link is lost during initialization.
This happens because the driver access device after EECD register reads
return all F's, indicating failed reads. Consequently, hw->hw_addr is set
to NULL, which impacts subsequent rd32() reads. This leads to the driver
hanging in igc_get_hw_semaphore_i225(), as the invalid hw->hw_addr
prevents retrieving the expected value.
To address this, a validation check and a corresponding return value
catch is added for the EECD register read result. If all F's are
returned, indicating PCIe link loss, the driver will return -ENXIO
immediately. This avoids the 40-second hang and significantly improves
boot time when using a dock with an igc NIC.
Log before the patch:
[ 0.911913] igc 0000:70:00.0: enabling device (0000 -> 0002)
[ 0.912386] igc 0000:70:00.0: PTM enabled, 4ns granularity
[ 1.571098] igc 0000:70:00.0 (unnamed net_device) (uninitialized): PCIe link
lost, device now detached
[ 43.449095] igc_get_hw_semaphore_i225: igc 0000:70:00.0 (unnamed net_device)
(uninitialized): Driver can't access device - SMBI bit is set.
[ 43.449186] igc 0000:70:00.0: probe with driver igc failed with error -13
[ 46.345701] igc 0000:70:00.0: enabling device (0000 -> 0002)
[ 46.345777] igc 0000:70:00.0: PTM enabled, 4ns granularity
Log after the patch:
[ 1.031000] igc 0000:70:00.0: enabling device (0000 -> 0002)
[ 1.032097] igc 0000:70:00.0: PTM enabled, 4ns granularity
[ 1.642291] igc 0000:70:00.0 (unnamed net_device) (uninitialized): PCIe link
lost, device now detached
[ 5.480490] igc 0000:70:00.0: enabling device (0000 -> 0002)
[ 5.480516] igc 0000:70:00.0: PTM enabled, 4ns granularity
Fixes: ab4056126813 ("igc: Add NVM support")
Cc: Chia-Lin Kao (AceLan) <[email protected]>
Signed-off-by: En-Wei Wu <[email protected]>
---
Changes in v2:
- Added "after" logs showing improved boot time
- Fixed error code (use -ENXIO instead of -ENODEV)
- Added error propagation in igc_get_invariants_base()
- Added Fixes tag
- Added [PATCH iwl-net] prefix
- Changed original author from AceLan to En-Wei
drivers/net/ethernet/intel/igc/igc_base.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/drivers/net/ethernet/intel/igc/igc_base.c
b/drivers/net/ethernet/intel/igc/igc_base.c
index 9fae8bdec2a7..1613b562d17c 100644
--- a/drivers/net/ethernet/intel/igc/igc_base.c
+++ b/drivers/net/ethernet/intel/igc/igc_base.c
@@ -68,6 +68,10 @@ static s32 igc_init_nvm_params_base(struct igc_hw *hw)
u32 eecd = rd32(IGC_EECD);
u16 size;
+ /* failed to read reg and got all F's */
+ if (!(~eecd))
+ return -ENXIO;
+
size = FIELD_GET(IGC_EECD_SIZE_EX_MASK, eecd);
/* Added to a constant, "size" becomes the left-shift value
@@ -221,6 +225,8 @@ static s32 igc_get_invariants_base(struct igc_hw *hw)
/* NVM initialization */
ret_val = igc_init_nvm_params_base(hw);
+ if (ret_val)
+ goto out;
switch (hw->mac.type) {
case igc_i225:
ret_val = igc_init_nvm_params_i225(hw);
--
2.43.0
