From patchwork Fri Dec 2 20:30:22 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Grygorii Strashko X-Patchwork-Id: 702117 Return-Path: X-Original-To: incoming-dt@patchwork.ozlabs.org Delivered-To: patchwork-incoming-dt@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3tVm9f3b8Qz9t1T for ; Sat, 3 Dec 2016 07:35:02 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760066AbcLBUeC (ORCPT ); Fri, 2 Dec 2016 15:34:02 -0500 Received: from fllnx210.ext.ti.com ([198.47.19.17]:13421 "EHLO fllnx210.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754747AbcLBUar (ORCPT ); Fri, 2 Dec 2016 15:30:47 -0500 Received: from dflxv15.itg.ti.com ([128.247.5.124]) by fllnx210.ext.ti.com (8.15.1/8.15.1) with ESMTP id uB2KUTTp003232; Fri, 2 Dec 2016 14:30:29 -0600 Received: from DFLE72.ent.ti.com (dfle72.ent.ti.com [128.247.5.109]) by dflxv15.itg.ti.com (8.14.3/8.13.8) with ESMTP id uB2KUTqZ015068; Fri, 2 Dec 2016 14:30:29 -0600 Received: from dlep32.itg.ti.com (157.170.170.100) by DFLE72.ent.ti.com (128.247.5.109) with Microsoft SMTP Server id 14.3.294.0; Fri, 2 Dec 2016 14:30:28 -0600 Received: from legion.dal.design.ti.com (legion.dal.design.ti.com [128.247.22.53]) by dlep32.itg.ti.com (8.14.3/8.13.8) with ESMTP id uB2KUSRp005589; Fri, 2 Dec 2016 14:30:28 -0600 Received: from localhost (uda0226610.am.dhcp.ti.com [128.247.83.173]) by legion.dal.design.ti.com (8.11.7p1+Sun/8.11.7) with ESMTP id uB2KUS325383; Fri, 2 Dec 2016 14:30:28 -0600 (CST) From: Grygorii Strashko To: "David S. Miller" , , Mugunthan V N , Richard Cochran CC: Sekhar Nori , , , Rob Herring , , Murali Karicheri , Wingman Kwok , Thomas Gleixner , Grygorii Strashko , John Stultz Subject: [PATCH v3 12/13] net: ethernet: ti: cpts: calc mult and shift from refclk freq Date: Fri, 2 Dec 2016 14:30:22 -0600 Message-ID: <20161202203023.25526-13-grygorii.strashko@ti.com> X-Mailer: git-send-email 2.10.1 In-Reply-To: <20161202203023.25526-1-grygorii.strashko@ti.com> References: <20161202203023.25526-1-grygorii.strashko@ti.com> MIME-Version: 1.0 Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org The cyclecounter mult and shift values can be calculated based on the CPTS rfclk frequency and timekeepnig framework provides required algos and API's. Hence, calc mult and shift basing on CPTS rfclk frequency if both cpts_clock_shift and cpts_clock_mult properties are not provided in DT (the basis of calculation algorithm is borrowed from __clocksource_update_freq_scale() commit 7d2f944a2b83 ("clocksource: Provide a generic mult/shift factor calculation")). After this change cpts_clock_shift and cpts_clock_mult DT properties will become optional. Cc: John Stultz Cc: Thomas Gleixner Signed-off-by: Grygorii Strashko --- Documentation/devicetree/bindings/net/cpsw.txt | 8 ++-- drivers/net/ethernet/ti/cpts.c | 53 +++++++++++++++++++++++--- 2 files changed, 52 insertions(+), 9 deletions(-) diff --git a/Documentation/devicetree/bindings/net/cpsw.txt b/Documentation/devicetree/bindings/net/cpsw.txt index 5ad439f..ebda7c9 100644 --- a/Documentation/devicetree/bindings/net/cpsw.txt +++ b/Documentation/devicetree/bindings/net/cpsw.txt @@ -20,8 +20,6 @@ Required properties: - slaves : Specifies number for slaves - active_slave : Specifies the slave to use for time stamping, ethtool and SIOCGMIIPHY -- cpts_clock_mult : Numerator to convert input clock ticks into nanoseconds -- cpts_clock_shift : Denominator to convert input clock ticks into nanoseconds Optional properties: - ti,hwmods : Must be "cpgmac0" @@ -35,7 +33,11 @@ Optional properties: For example in dra72x-evm, pcf gpio has to be driven low so that cpsw slave 0 and phy data lines are connected via mux. - +- cpts_clock_mult : Numerator to convert input clock ticks into nanoseconds +- cpts_clock_shift : Denominator to convert input clock ticks into nanoseconds + Mult and shift will be calculated basing on CPTS + rftclk frequency if both cpts_clock_shift and + cpts_clock_mult properties are not provided. Slave Properties: Required properties: diff --git a/drivers/net/ethernet/ti/cpts.c b/drivers/net/ethernet/ti/cpts.c index 5d5c46d..806241b 100644 --- a/drivers/net/ethernet/ti/cpts.c +++ b/drivers/net/ethernet/ti/cpts.c @@ -409,21 +409,60 @@ void cpts_unregister(struct cpts *cpts) } EXPORT_SYMBOL_GPL(cpts_unregister); +static void cpts_calc_mult_shift(struct cpts *cpts) +{ + u64 frac, maxsec, ns; + u32 freq, mult, shift; + + freq = clk_get_rate(cpts->refclk); + + /* Calc the maximum number of seconds which we can run before + * wrapping around. + */ + maxsec = cpts->cc.mask; + do_div(maxsec, freq); + /* limit conversation rate to 10 sec as higher values will produce + * too small mult factors and so reduce the conversion accuracy + */ + if (maxsec > 10) + maxsec = 10; + + 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; + + frac = 0; + ns = cyclecounter_cyc2ns(&cpts->cc, freq, cpts->cc.mask, &frac); + + dev_info(cpts->dev, + "CPTS: ref_clk_freq:%u calc_mult:%u calc_shift:%u error:%lld nsec/sec\n", + freq, cpts->cc_mult, cpts->cc.shift, (ns - NSEC_PER_SEC)); +} + static int cpts_of_parse(struct cpts *cpts, struct device_node *node) { int ret = -EINVAL; u32 prop; - if (of_property_read_u32(node, "cpts_clock_mult", &prop)) - goto of_error; /* save cc.mult original value as it can be modified * by cpts_ptp_adjfreq(). */ - cpts->cc_mult = prop; + cpts->cc_mult = 0; + if (!of_property_read_u32(node, "cpts_clock_mult", &prop)) + cpts->cc_mult = prop; + + cpts->cc.shift = 0; + if (!of_property_read_u32(node, "cpts_clock_shift", &prop)) + cpts->cc.shift = prop; - if (of_property_read_u32(node, "cpts_clock_shift", &prop)) - goto of_error; - cpts->cc.shift = prop; + if ((cpts->cc_mult && !cpts->cc.shift) || + (!cpts->cc_mult && cpts->cc.shift)) + goto of_error; return 0; @@ -463,6 +502,8 @@ struct cpts *cpts_create(struct device *dev, void __iomem *regs, cpts->cc.mask = CLOCKSOURCE_MASK(32); cpts->info = cpts_info; + cpts_calc_mult_shift(cpts); + return cpts; } EXPORT_SYMBOL_GPL(cpts_create);