From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jiri Benc Subject: [PATCH] igb: fix PHC stopping on max freq Date: Tue, 19 Mar 2013 15:42:51 +0100 Message-ID: Cc: e1000-devel@lists.sourceforge.net, Jeff Kirsher , Stefan Assmann , Miroslav Lichvar To: netdev@vger.kernel.org Return-path: Received: from mx1.redhat.com ([209.132.183.28]:50780 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753152Ab3CSOnu (ORCPT ); Tue, 19 Mar 2013 10:43:50 -0400 Sender: netdev-owner@vger.kernel.org List-ID: For 82576 MAC type, max_adj is reported as 1000000000 ppb. However, if this value is passed to igb_ptp_adjfreq_82576, incvalue overflows out of INCVALUE_82576_MASK, resulting in setting of zero TIMINCA.incvalue, stopping the PHC (instead of going at twice the nominal speed). Fix the advertised max_adj value to the largest value hardware can handle. As there is no min_adj value available (-max_adj is used instead), this will also prevent stopping the clock intentionally. It's probably not a big deal, other igb MAC types don't support stopping the clock, either. Signed-off-by: Jiri Benc --- drivers/net/ethernet/intel/igb/igb_ptp.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/drivers/net/ethernet/intel/igb/igb_ptp.c b/drivers/net/ethernet/intel/igb/igb_ptp.c index 0987822..0a23750 100644 --- a/drivers/net/ethernet/intel/igb/igb_ptp.c +++ b/drivers/net/ethernet/intel/igb/igb_ptp.c @@ -740,7 +740,7 @@ void igb_ptp_init(struct igb_adapter *adapter) case e1000_82576: snprintf(adapter->ptp_caps.name, 16, "%pm", netdev->dev_addr); adapter->ptp_caps.owner = THIS_MODULE; - adapter->ptp_caps.max_adj = 1000000000; + adapter->ptp_caps.max_adj = 999999881; adapter->ptp_caps.n_ext_ts = 0; adapter->ptp_caps.pps = 0; adapter->ptp_caps.adjfreq = igb_ptp_adjfreq_82576; -- 1.7.6.5