diff options
| author | Heiko Thiery <heiko.thiery@gmail.com> | 2021-02-25 22:15:16 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-03-30 14:44:58 +0200 |
| commit | 9b4ab2e13bed61f2adf9db10bcdebb109e18329b (patch) | |
| tree | 4e05d1b00367274425500ebe69ea6998597ce629 /drivers/net | |
| parent | 4d422f6e1358d7eb9f493ec832e8cf0b8e6bc28d (diff) | |
net: fec: ptp: avoid register access when ipg clock is disabled
[ Upstream commit 6a4d7234ae9a3bb31181f348ade9bbdb55aeb5c5 ]
When accessing the timecounter register on an i.MX8MQ the kernel hangs.
This is only the case when the interface is down. This can be reproduced
by reading with 'phc_ctrl eth0 get'.
Like described in the change in 91c0d987a9788dcc5fe26baafd73bf9242b68900
the igp clock is disabled when the interface is down and leads to a
system hang.
So we check if the ptp clock status before reading the timecounter
register.
Signed-off-by: Heiko Thiery <heiko.thiery@gmail.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Link: https://lore.kernel.org/r/20210225211514.9115-1-heiko.thiery@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers/net')
| -rw-r--r-- | drivers/net/ethernet/freescale/fec_ptp.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/drivers/net/ethernet/freescale/fec_ptp.c b/drivers/net/ethernet/freescale/fec_ptp.c index f9e74461bdc0..123181612595 100644 --- a/drivers/net/ethernet/freescale/fec_ptp.c +++ b/drivers/net/ethernet/freescale/fec_ptp.c @@ -396,9 +396,16 @@ static int fec_ptp_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts) u64 ns; unsigned long flags; + mutex_lock(&adapter->ptp_clk_mutex); + /* Check the ptp clock */ + if (!adapter->ptp_clk_on) { + mutex_unlock(&adapter->ptp_clk_mutex); + return -EINVAL; + } spin_lock_irqsave(&adapter->tmreg_lock, flags); ns = timecounter_read(&adapter->tc); spin_unlock_irqrestore(&adapter->tmreg_lock, flags); + mutex_unlock(&adapter->ptp_clk_mutex); *ts = ns_to_timespec64(ns); |