From patchwork Tue Jun 15 09:45:09 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yangbo Lu X-Patchwork-Id: 12320999 Received: from inva020.nxp.com (inva020.nxp.com [92.121.34.13]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 64B0A6D0E for ; Tue, 15 Jun 2021 09:46:14 +0000 (UTC) Received: from inva020.nxp.com (localhost [127.0.0.1]) by inva020.eu-rdc02.nxp.com (Postfix) with ESMTP id 6B9F01A29D4; Tue, 15 Jun 2021 11:36:35 +0200 (CEST) Received: from invc005.ap-rdc01.nxp.com (invc005.ap-rdc01.nxp.com [165.114.16.14]) by inva020.eu-rdc02.nxp.com (Postfix) with ESMTP id 299DB1A16D4; Tue, 15 Jun 2021 11:36:29 +0200 (CEST) Received: from localhost.localdomain (mega.ap.freescale.net [10.192.208.232]) by invc005.ap-rdc01.nxp.com (Postfix) with ESMTP id 865B240327; Tue, 15 Jun 2021 17:36:21 +0800 (+08) From: Yangbo Lu To: netdev@vger.kernel.org Cc: Yangbo Lu , linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, mptcp@lists.linux.dev, Richard Cochran , "David S . Miller" , Jakub Kicinski , Mat Martineau , Matthieu Baerts , Shuah Khan , Michal Kubecek , Florian Fainelli , Andrew Lunn , Rui Sousa , Sebastien Laveze Subject: [net-next, v3, 02/10] ptp: support ptp physical/virtual clocks conversion Date: Tue, 15 Jun 2021 17:45:09 +0800 Message-Id: <20210615094517.48752-3-yangbo.lu@nxp.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20210615094517.48752-1-yangbo.lu@nxp.com> References: <20210615094517.48752-1-yangbo.lu@nxp.com> X-Virus-Scanned: ClamAV using ClamSMTP X-Mailing-List: mptcp@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: Support ptp physical/virtual clocks conversion via sysfs. There will be a new attribute n_vclocks under ptp physical clock sysfs. - In default, the value is 0 meaning only ptp physical clock is in use. - Setting the value can create corresponding number of ptp virtual clocks to use. But current physical clock is guaranteed to stay free running. - Setting the value back to 0 can delete virtual clocks and back use physical clock again. Signed-off-by: Yangbo Lu --- Changes for v2: - Split from v1 patch #2. - Converted to num_vclocks for creating virtual clocks. - Guranteed physical clock free running when using virtual clocks. - Fixed build warning. - Updated copyright. Changes for v3: - Protected concurrency of ptp->num_vclocks accessing. --- Documentation/ABI/testing/sysfs-ptp | 13 +++++ drivers/ptp/ptp_clock.c | 22 +++++++ drivers/ptp/ptp_private.h | 15 +++++ drivers/ptp/ptp_sysfs.c | 89 +++++++++++++++++++++++++++++ include/uapi/linux/ptp_clock.h | 5 ++ 5 files changed, 144 insertions(+) diff --git a/Documentation/ABI/testing/sysfs-ptp b/Documentation/ABI/testing/sysfs-ptp index 2363ad810ddb..2ef11b775f47 100644 --- a/Documentation/ABI/testing/sysfs-ptp +++ b/Documentation/ABI/testing/sysfs-ptp @@ -61,6 +61,19 @@ Description: This file contains the number of programmable pins offered by the PTP hardware clock. +What: /sys/class/ptp/ptpN/n_vclocks +Date: May 2021 +Contact: Yangbo Lu +Description: + This file contains the ptp virtual clocks number in use, + based on current ptp physical clock. In default, the + value is 0 meaning only ptp physical clock is in use. + Setting the value can create corresponding number of ptp + virtual clocks to use. But current ptp physical clock is + guaranteed to stay free running. Setting the value back + to 0 can delete ptp virtual clocks and back use ptp + physical clock again. + What: /sys/class/ptp/ptpN/pins Date: March 2014 Contact: Richard Cochran diff --git a/drivers/ptp/ptp_clock.c b/drivers/ptp/ptp_clock.c index a780435331c8..78414b3e16dd 100644 --- a/drivers/ptp/ptp_clock.c +++ b/drivers/ptp/ptp_clock.c @@ -76,6 +76,11 @@ static int ptp_clock_settime(struct posix_clock *pc, const struct timespec64 *tp { struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock); + if (ptp_guaranteed_pclock(ptp)) { + pr_err("ptp: virtual clock in use, guarantee physical clock free running\n"); + return -EBUSY; + } + return ptp->info->settime64(ptp->info, tp); } @@ -97,6 +102,11 @@ static int ptp_clock_adjtime(struct posix_clock *pc, struct __kernel_timex *tx) struct ptp_clock_info *ops; int err = -EOPNOTSUPP; + if (ptp_guaranteed_pclock(ptp)) { + pr_err("ptp: virtual clock in use, guarantee physical clock free running\n"); + return -EBUSY; + } + ops = ptp->info; if (tx->modes & ADJ_SETOFFSET) { @@ -161,6 +171,7 @@ static void ptp_clock_release(struct device *dev) ptp_cleanup_pin_groups(ptp); mutex_destroy(&ptp->tsevq_mux); mutex_destroy(&ptp->pincfg_mux); + mutex_destroy(&ptp->n_vclocks_mux); ida_simple_remove(&ptp_clocks_map, ptp->index); kfree(ptp); } @@ -208,6 +219,7 @@ struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info, spin_lock_init(&ptp->tsevq.lock); mutex_init(&ptp->tsevq_mux); mutex_init(&ptp->pincfg_mux); + mutex_init(&ptp->n_vclocks_mux); init_waitqueue_head(&ptp->tsev_wq); if (ptp->info->do_aux_work) { @@ -220,6 +232,10 @@ struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info, } } + /* PTP virtual clock is being registered under physical clock */ + if (parent->class && strcmp(parent->class->name, "ptp") == 0) + ptp->vclock_flag = true; + err = ptp_populate_pin_groups(ptp); if (err) goto no_pin_groups; @@ -269,6 +285,7 @@ struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info, kworker_err: mutex_destroy(&ptp->tsevq_mux); mutex_destroy(&ptp->pincfg_mux); + mutex_destroy(&ptp->n_vclocks_mux); ida_simple_remove(&ptp_clocks_map, index); no_slot: kfree(ptp); @@ -279,6 +296,11 @@ EXPORT_SYMBOL(ptp_clock_register); int ptp_clock_unregister(struct ptp_clock *ptp) { + if (ptp_guaranteed_pclock(ptp)) { + pr_err("ptp: virtual clock in use, guarantee physical clock free running\n"); + return -EBUSY; + } + ptp->defunct = 1; wake_up_interruptible(&ptp->tsev_wq); diff --git a/drivers/ptp/ptp_private.h b/drivers/ptp/ptp_private.h index 3f388d63904c..6949afc9d733 100644 --- a/drivers/ptp/ptp_private.h +++ b/drivers/ptp/ptp_private.h @@ -46,6 +46,9 @@ struct ptp_clock { const struct attribute_group *pin_attr_groups[2]; struct kthread_worker *kworker; struct kthread_delayed_work aux_work; + u8 n_vclocks; + struct mutex n_vclocks_mux; /* protect concurrent n_vclocks access */ + bool vclock_flag; }; #define info_to_vclock(d) container_of((d), struct ptp_vclock, info) @@ -75,6 +78,18 @@ static inline int queue_cnt(struct timestamp_event_queue *q) return cnt < 0 ? PTP_MAX_TIMESTAMPS + cnt : cnt; } +/* + * Guarantee physical clock to stay free running, if ptp virtual clocks + * on it are in use. + */ +static inline bool ptp_guaranteed_pclock(struct ptp_clock *ptp) +{ + if (!ptp->vclock_flag && ptp->n_vclocks) + return true; + + return false; +} + /* * see ptp_chardev.c */ diff --git a/drivers/ptp/ptp_sysfs.c b/drivers/ptp/ptp_sysfs.c index be076a91e20e..600edd7a90af 100644 --- a/drivers/ptp/ptp_sysfs.c +++ b/drivers/ptp/ptp_sysfs.c @@ -3,6 +3,7 @@ * PTP 1588 clock support - sysfs interface. * * Copyright (C) 2010 OMICRON electronics GmbH + * Copyright 2021 NXP */ #include #include @@ -148,6 +149,90 @@ static ssize_t pps_enable_store(struct device *dev, } static DEVICE_ATTR(pps_enable, 0220, NULL, pps_enable_store); +static int unregister_vclock(struct device *dev, void *data) +{ + struct ptp_clock *ptp = dev_get_drvdata(dev); + struct ptp_clock_info *info = ptp->info; + struct ptp_vclock *vclock; + u8 *num = data; + + vclock = info_to_vclock(info); + dev_info(dev->parent, "delete virtual clock ptp%d\n", + vclock->clock->index); + + ptp_vclock_unregister(vclock); + (*num)--; + + /* For break. Not error. */ + if (*num == 0) + return -EINVAL; + + return 0; +} + +static ssize_t n_vclocks_show(struct device *dev, + struct device_attribute *attr, char *page) +{ + struct ptp_clock *ptp = dev_get_drvdata(dev); + + return snprintf(page, PAGE_SIZE-1, "%d\n", ptp->n_vclocks); +} + +static ssize_t n_vclocks_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct ptp_clock *ptp = dev_get_drvdata(dev); + struct ptp_vclock *vclock; + int err = -EINVAL; + u8 num, i; + + if (kstrtou8(buf, 0, &num)) + goto out; + + if (num > PTP_MAX_VCLOCKS) { + dev_err(dev, "max value is %d\n", PTP_MAX_VCLOCKS); + goto out; + } + + if (mutex_lock_interruptible(&ptp->n_vclocks_mux)) + return -ERESTARTSYS; + + /* Need to create more vclocks */ + if (num > ptp->n_vclocks) { + for (i = 0; i < num - ptp->n_vclocks; i++) { + vclock = ptp_vclock_register(ptp); + if (!vclock) { + mutex_unlock(&ptp->n_vclocks_mux); + goto out; + } + + dev_info(dev, "new virtual clock ptp%d\n", + vclock->clock->index); + } + } + + /* Need to delete vclocks */ + if (num < ptp->n_vclocks) { + i = ptp->n_vclocks - num; + device_for_each_child_reverse(dev, &i, + unregister_vclock); + } + + if (num == 0) + dev_info(dev, "only physical clock in use now\n"); + else + dev_info(dev, "guarantee physical clock free running\n"); + + ptp->n_vclocks = num; + mutex_unlock(&ptp->n_vclocks_mux); + + return count; +out: + return err; +} +static DEVICE_ATTR_RW(n_vclocks); + static struct attribute *ptp_attrs[] = { &dev_attr_clock_name.attr, @@ -162,6 +247,7 @@ static struct attribute *ptp_attrs[] = { &dev_attr_fifo.attr, &dev_attr_period.attr, &dev_attr_pps_enable.attr, + &dev_attr_n_vclocks.attr, NULL }; @@ -183,6 +269,9 @@ static umode_t ptp_is_attribute_visible(struct kobject *kobj, } else if (attr == &dev_attr_pps_enable.attr) { if (!info->pps) mode = 0; + } else if (attr == &dev_attr_n_vclocks.attr) { + if (ptp->vclock_flag) + mode = 0; } return mode; diff --git a/include/uapi/linux/ptp_clock.h b/include/uapi/linux/ptp_clock.h index 1d108d597f66..4b933dc1b81b 100644 --- a/include/uapi/linux/ptp_clock.h +++ b/include/uapi/linux/ptp_clock.h @@ -69,6 +69,11 @@ */ #define PTP_PEROUT_V1_VALID_FLAGS (0) +/* + * Max number of PTP virtual clocks per PTP physical clock + */ +#define PTP_MAX_VCLOCKS 20 + /* * struct ptp_clock_time - represents a time value *