6.14-stable review patch. If anyone has any objections, please let me know.
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From: Christopher S M Hall christopher.s.hall@intel.com
[ Upstream commit 1a931c4f5e6862e61a4b130cb76b422e1415f644 ]
Add a mutex around the PTM transaction to prevent multiple transactors
Multiple processes try to initiate a PTM transaction, one or all may fail. This can be reproduced by running two instances of the following:
$ sudo phc2sys -O 0 -i tsn0 -m
PHC2SYS exits with:
"ioctl PTP_OFFSET_PRECISE: Connection timed out" when the PTM transaction fails
Note: Normally two instance of PHC2SYS will not run, but one process should not break another.
Fixes: a90ec8483732 ("igc: Add support for PTP getcrosststamp()") Signed-off-by: Christopher S M Hall christopher.s.hall@intel.com Reviewed-by: Corinna Vinschen vinschen@redhat.com Signed-off-by: Jacob Keller jacob.e.keller@intel.com Tested-by: Mor Bar-Gabay morx.bar.gabay@intel.com Acked-by: Vinicius Costa Gomes vinicius.gomes@intel.com Signed-off-by: Tony Nguyen anthony.l.nguyen@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/intel/igc/igc.h | 1 + drivers/net/ethernet/intel/igc/igc_ptp.c | 20 ++++++++++++++++++-- 2 files changed, 19 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/intel/igc/igc.h b/drivers/net/ethernet/intel/igc/igc.h index c35cc5cb11856..2f265c0959c7a 100644 --- a/drivers/net/ethernet/intel/igc/igc.h +++ b/drivers/net/ethernet/intel/igc/igc.h @@ -319,6 +319,7 @@ struct igc_adapter { struct timespec64 prev_ptp_time; /* Pre-reset PTP clock */ ktime_t ptp_reset_start; /* Reset time in clock mono */ struct system_time_snapshot snapshot; + struct mutex ptm_lock; /* Only allow one PTM transaction at a time */
char fw_version[32];
diff --git a/drivers/net/ethernet/intel/igc/igc_ptp.c b/drivers/net/ethernet/intel/igc/igc_ptp.c index 343205bffc355..612ed26a29c5d 100644 --- a/drivers/net/ethernet/intel/igc/igc_ptp.c +++ b/drivers/net/ethernet/intel/igc/igc_ptp.c @@ -974,6 +974,7 @@ static void igc_ptm_log_error(struct igc_adapter *adapter, u32 ptm_stat) } }
+/* The PTM lock: adapter->ptm_lock must be held when calling igc_ptm_trigger() */ static void igc_ptm_trigger(struct igc_hw *hw) { u32 ctrl; @@ -990,6 +991,7 @@ static void igc_ptm_trigger(struct igc_hw *hw) wrfl(); }
+/* The PTM lock: adapter->ptm_lock must be held when calling igc_ptm_reset() */ static void igc_ptm_reset(struct igc_hw *hw) { u32 ctrl; @@ -1068,9 +1070,16 @@ static int igc_ptp_getcrosststamp(struct ptp_clock_info *ptp, { struct igc_adapter *adapter = container_of(ptp, struct igc_adapter, ptp_caps); + int ret;
- return get_device_system_crosststamp(igc_phc_get_syncdevicetime, - adapter, &adapter->snapshot, cts); + /* This blocks until any in progress PTM transactions complete */ + mutex_lock(&adapter->ptm_lock); + + ret = get_device_system_crosststamp(igc_phc_get_syncdevicetime, + adapter, &adapter->snapshot, cts); + mutex_unlock(&adapter->ptm_lock); + + return ret; }
static int igc_ptp_getcyclesx64(struct ptp_clock_info *ptp, @@ -1169,6 +1178,7 @@ void igc_ptp_init(struct igc_adapter *adapter) spin_lock_init(&adapter->ptp_tx_lock); spin_lock_init(&adapter->free_timer_lock); spin_lock_init(&adapter->tmreg_lock); + mutex_init(&adapter->ptm_lock);
adapter->tstamp_config.rx_filter = HWTSTAMP_FILTER_NONE; adapter->tstamp_config.tx_type = HWTSTAMP_TX_OFF; @@ -1181,6 +1191,7 @@ void igc_ptp_init(struct igc_adapter *adapter) if (IS_ERR(adapter->ptp_clock)) { adapter->ptp_clock = NULL; netdev_err(netdev, "ptp_clock_register failed\n"); + mutex_destroy(&adapter->ptm_lock); } else if (adapter->ptp_clock) { netdev_info(netdev, "PHC added\n"); adapter->ptp_flags |= IGC_PTP_ENABLED; @@ -1210,10 +1221,12 @@ static void igc_ptm_stop(struct igc_adapter *adapter) struct igc_hw *hw = &adapter->hw; u32 ctrl;
+ mutex_lock(&adapter->ptm_lock); ctrl = rd32(IGC_PTM_CTRL); ctrl &= ~IGC_PTM_CTRL_EN;
wr32(IGC_PTM_CTRL, ctrl); + mutex_unlock(&adapter->ptm_lock); }
/** @@ -1255,6 +1268,7 @@ void igc_ptp_stop(struct igc_adapter *adapter) netdev_info(adapter->netdev, "PHC removed\n"); adapter->ptp_flags &= ~IGC_PTP_ENABLED; } + mutex_destroy(&adapter->ptm_lock); }
/** @@ -1294,6 +1308,7 @@ void igc_ptp_reset(struct igc_adapter *adapter) if (!igc_is_crosststamp_supported(adapter)) break;
+ mutex_lock(&adapter->ptm_lock); wr32(IGC_PCIE_DIG_DELAY, IGC_PCIE_DIG_DELAY_DEFAULT); wr32(IGC_PCIE_PHY_DELAY, IGC_PCIE_PHY_DELAY_DEFAULT);
@@ -1317,6 +1332,7 @@ void igc_ptp_reset(struct igc_adapter *adapter) netdev_err(adapter->netdev, "Timeout reading IGC_PTM_STAT register\n");
igc_ptm_reset(hw); + mutex_unlock(&adapter->ptm_lock); break; default: /* No work to do. */