From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762207AbcINNDG (ORCPT ); Wed, 14 Sep 2016 09:03:06 -0400 Received: from comal.ext.ti.com ([198.47.26.152]:51704 "EHLO comal.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1762124AbcINNCy (ORCPT ); Wed, 14 Sep 2016 09:02:54 -0400 From: Grygorii Strashko To: "David S. Miller" , , Mugunthan V N , Richard Cochran CC: Sekhar Nori , , , WingMan Kwok , Grygorii Strashko Subject: [PATCH 8/9] net: ethernet: ti: cpts: fix overflow check period Date: Wed, 14 Sep 2016 16:02:30 +0300 Message-ID: <20160914130231.3035-9-grygorii.strashko@ti.com> X-Mailer: git-send-email 2.9.3 In-Reply-To: <20160914130231.3035-1-grygorii.strashko@ti.com> References: <20160914130231.3035-1-grygorii.strashko@ti.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The CPTS drivers uses 8sec period for overflow checking with assumption that CPTS rftclk will not exceed 500MHz. But that's not true on some TI's platforms (Kesytone 2). As result, it is possible that CPTS counter will overflow more than once between two readings. Hence, fix it by selecting overflow check period dynamically as max_sec_before_overflow/2, where max_sec_before_overflow = max_counter_val / rftclk_freq. Signed-off-by: Grygorii Strashko --- drivers/net/ethernet/ti/cpts.c | 16 +++++++++++----- drivers/net/ethernet/ti/cpts.h | 4 +--- 2 files changed, 12 insertions(+), 8 deletions(-) diff --git a/drivers/net/ethernet/ti/cpts.c b/drivers/net/ethernet/ti/cpts.c index 8046a21..cbe0974 100644 --- a/drivers/net/ethernet/ti/cpts.c +++ b/drivers/net/ethernet/ti/cpts.c @@ -251,7 +251,7 @@ static void cpts_overflow_check(struct work_struct *work) cpts_write32(cpts, TS_PEND_EN, int_enable); cpts_ptp_gettime(&cpts->info, &ts); pr_debug("cpts overflow check at %lld.%09lu\n", ts.tv_sec, ts.tv_nsec); - schedule_delayed_work(&cpts->overflow_work, CPTS_OVERFLOW_PERIOD); + schedule_delayed_work(&cpts->overflow_work, cpts->ov_check_period); } static int cpts_match(struct sk_buff *skb, unsigned int ptp_class, @@ -391,7 +391,7 @@ int cpts_register(struct cpts *cpts) } cpts->phc_index = ptp_clock_index(cpts->clock); - schedule_delayed_work(&cpts->overflow_work, CPTS_OVERFLOW_PERIOD); + schedule_delayed_work(&cpts->overflow_work, cpts->ov_check_period); return 0; err_ptp: @@ -427,9 +427,6 @@ static void cpts_calc_mult_shift(struct cpts *cpts) u64 ns; u64 frac; - if (cpts->cc_mult || cpts->cc.shift) - return; - freq = clk_get_rate(cpts->refclk); /* Calc the maximum number of seconds which we can run before @@ -442,11 +439,20 @@ static void cpts_calc_mult_shift(struct cpts *cpts) else if (maxsec > 600 && cpts->cc.mask > UINT_MAX) maxsec = 600; + /* Calc overflow check period (maxsec / 2) */ + cpts->ov_check_period = (HZ * maxsec) / 2; + dev_info(cpts->dev, "cpts: overflow check period %lu\n", + cpts->ov_check_period); + + if (cpts->cc_mult || cpts->cc.shift) + return; + clocks_calc_mult_shift(&mult, &shift, freq, NSEC_PER_SEC, maxsec); cpts->cc_mult = mult; cpts->cc.mult = mult; cpts->cc.shift = shift; + /* Check calculations and inform if not precise */ frac = 0; ns = cyclecounter_cyc2ns(&cpts->cc, freq, cpts->cc.mask, &frac); diff --git a/drivers/net/ethernet/ti/cpts.h b/drivers/net/ethernet/ti/cpts.h index 47026ec..e0e4a62b 100644 --- a/drivers/net/ethernet/ti/cpts.h +++ b/drivers/net/ethernet/ti/cpts.h @@ -97,9 +97,6 @@ enum { CPTS_EV_TX, /* Ethernet Transmit Event */ }; -/* This covers any input clock up to about 500 MHz. */ -#define CPTS_OVERFLOW_PERIOD (HZ * 8) - #define CPTS_FIFO_DEPTH 16 #define CPTS_MAX_EVENTS 32 @@ -127,6 +124,7 @@ struct cpts { struct list_head events; struct list_head pool; struct cpts_event pool_data[CPTS_MAX_EVENTS]; + unsigned long ov_check_period; }; int cpts_rx_timestamp(struct cpts *cpts, struct sk_buff *skb); -- 2.9.3 From mboxrd@z Thu Jan 1 00:00:00 1970 From: Grygorii Strashko Subject: [PATCH 8/9] net: ethernet: ti: cpts: fix overflow check period Date: Wed, 14 Sep 2016 16:02:30 +0300 Message-ID: <20160914130231.3035-9-grygorii.strashko@ti.com> References: <20160914130231.3035-1-grygorii.strashko@ti.com> Mime-Version: 1.0 Content-Type: text/plain Return-path: In-Reply-To: <20160914130231.3035-1-grygorii.strashko@ti.com> Sender: netdev-owner@vger.kernel.org To: "David S. Miller" , netdev@vger.kernel.org, Mugunthan V N , Richard Cochran Cc: Sekhar Nori , linux-kernel@vger.kernel.org, linux-omap@vger.kernel.org, WingMan Kwok , Grygorii Strashko List-Id: linux-omap@vger.kernel.org The CPTS drivers uses 8sec period for overflow checking with assumption that CPTS rftclk will not exceed 500MHz. But that's not true on some TI's platforms (Kesytone 2). As result, it is possible that CPTS counter will overflow more than once between two readings. Hence, fix it by selecting overflow check period dynamically as max_sec_before_overflow/2, where max_sec_before_overflow = max_counter_val / rftclk_freq. Signed-off-by: Grygorii Strashko --- drivers/net/ethernet/ti/cpts.c | 16 +++++++++++----- drivers/net/ethernet/ti/cpts.h | 4 +--- 2 files changed, 12 insertions(+), 8 deletions(-) diff --git a/drivers/net/ethernet/ti/cpts.c b/drivers/net/ethernet/ti/cpts.c index 8046a21..cbe0974 100644 --- a/drivers/net/ethernet/ti/cpts.c +++ b/drivers/net/ethernet/ti/cpts.c @@ -251,7 +251,7 @@ static void cpts_overflow_check(struct work_struct *work) cpts_write32(cpts, TS_PEND_EN, int_enable); cpts_ptp_gettime(&cpts->info, &ts); pr_debug("cpts overflow check at %lld.%09lu\n", ts.tv_sec, ts.tv_nsec); - schedule_delayed_work(&cpts->overflow_work, CPTS_OVERFLOW_PERIOD); + schedule_delayed_work(&cpts->overflow_work, cpts->ov_check_period); } static int cpts_match(struct sk_buff *skb, unsigned int ptp_class, @@ -391,7 +391,7 @@ int cpts_register(struct cpts *cpts) } cpts->phc_index = ptp_clock_index(cpts->clock); - schedule_delayed_work(&cpts->overflow_work, CPTS_OVERFLOW_PERIOD); + schedule_delayed_work(&cpts->overflow_work, cpts->ov_check_period); return 0; err_ptp: @@ -427,9 +427,6 @@ static void cpts_calc_mult_shift(struct cpts *cpts) u64 ns; u64 frac; - if (cpts->cc_mult || cpts->cc.shift) - return; - freq = clk_get_rate(cpts->refclk); /* Calc the maximum number of seconds which we can run before @@ -442,11 +439,20 @@ static void cpts_calc_mult_shift(struct cpts *cpts) else if (maxsec > 600 && cpts->cc.mask > UINT_MAX) maxsec = 600; + /* Calc overflow check period (maxsec / 2) */ + cpts->ov_check_period = (HZ * maxsec) / 2; + dev_info(cpts->dev, "cpts: overflow check period %lu\n", + cpts->ov_check_period); + + if (cpts->cc_mult || cpts->cc.shift) + return; + clocks_calc_mult_shift(&mult, &shift, freq, NSEC_PER_SEC, maxsec); cpts->cc_mult = mult; cpts->cc.mult = mult; cpts->cc.shift = shift; + /* Check calculations and inform if not precise */ frac = 0; ns = cyclecounter_cyc2ns(&cpts->cc, freq, cpts->cc.mask, &frac); diff --git a/drivers/net/ethernet/ti/cpts.h b/drivers/net/ethernet/ti/cpts.h index 47026ec..e0e4a62b 100644 --- a/drivers/net/ethernet/ti/cpts.h +++ b/drivers/net/ethernet/ti/cpts.h @@ -97,9 +97,6 @@ enum { CPTS_EV_TX, /* Ethernet Transmit Event */ }; -/* This covers any input clock up to about 500 MHz. */ -#define CPTS_OVERFLOW_PERIOD (HZ * 8) - #define CPTS_FIFO_DEPTH 16 #define CPTS_MAX_EVENTS 32 @@ -127,6 +124,7 @@ struct cpts { struct list_head events; struct list_head pool; struct cpts_event pool_data[CPTS_MAX_EVENTS]; + unsigned long ov_check_period; }; int cpts_rx_timestamp(struct cpts *cpts, struct sk_buff *skb); -- 2.9.3