From patchwork Wed Jun 30 08:11:52 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yangbo Lu X-Patchwork-Id: 12351495 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 4DF802F80 for ; Wed, 30 Jun 2021 08:01:27 +0000 (UTC) Received: from inva020.nxp.com (localhost [127.0.0.1]) by inva020.eu-rdc02.nxp.com (Postfix) with ESMTP id 9A8CD1A0484; Wed, 30 Jun 2021 10:01:20 +0200 (CEST) Received: from aprdc01srsp001v.ap-rdc01.nxp.com (aprdc01srsp001v.ap-rdc01.nxp.com [165.114.16.16]) by inva020.eu-rdc02.nxp.com (Postfix) with ESMTP id 331621A16B2; Wed, 30 Jun 2021 10:01:20 +0200 (CEST) Received: from localhost.localdomain (mega.ap.freescale.net [10.192.208.232]) by aprdc01srsp001v.ap-rdc01.nxp.com (Postfix) with ESMTP id 32F14183AC99; Wed, 30 Jun 2021 16:01:18 +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, v5, 01/11] ptp: add ptp virtual clock driver framework Date: Wed, 30 Jun 2021 16:11:52 +0800 Message-Id: <20210630081202.4423-2-yangbo.lu@nxp.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20210630081202.4423-1-yangbo.lu@nxp.com> References: <20210630081202.4423-1-yangbo.lu@nxp.com> X-Virus-Scanned: ClamAV using ClamSMTP Precedence: bulk X-Mailing-List: mptcp@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: This patch is to add ptp virtual clock driver framework utilizing timecounter/cyclecounter. The patch just exports two essential APIs for PTP driver. - ptp_vclock_register() - ptp_vclock_unregister() Signed-off-by: Yangbo Lu --- Changes for v2: - Split from v1 patch #1. - Fixed build warning. - Updated copyright. Changes for v3: - Supported PTP virtual clock in default in PTP driver. Changes for v4: - Renamed some MACROs. - Used do_aux_work callback for vclock refreshing instead. - Other minor fixes. Changes for v5: - None. --- drivers/ptp/Makefile | 2 +- drivers/ptp/ptp_private.h | 15 ++++ drivers/ptp/ptp_vclock.c | 150 +++++++++++++++++++++++++++++++ include/linux/ptp_clock_kernel.h | 4 +- 4 files changed, 169 insertions(+), 2 deletions(-) create mode 100644 drivers/ptp/ptp_vclock.c diff --git a/drivers/ptp/Makefile b/drivers/ptp/Makefile index 8673d1743faa..28a6fe342d3e 100644 --- a/drivers/ptp/Makefile +++ b/drivers/ptp/Makefile @@ -3,7 +3,7 @@ # Makefile for PTP 1588 clock support. # -ptp-y := ptp_clock.o ptp_chardev.o ptp_sysfs.o +ptp-y := ptp_clock.o ptp_chardev.o ptp_sysfs.o ptp_vclock.o ptp_kvm-$(CONFIG_X86) := ptp_kvm_x86.o ptp_kvm_common.o ptp_kvm-$(CONFIG_HAVE_ARM_SMCCC) := ptp_kvm_arm.o ptp_kvm_common.o obj-$(CONFIG_PTP_1588_CLOCK) += ptp.o diff --git a/drivers/ptp/ptp_private.h b/drivers/ptp/ptp_private.h index 6b97155148f1..853b79b6b30e 100644 --- a/drivers/ptp/ptp_private.h +++ b/drivers/ptp/ptp_private.h @@ -48,6 +48,19 @@ struct ptp_clock { struct kthread_delayed_work aux_work; }; +#define info_to_vclock(d) container_of((d), struct ptp_vclock, info) +#define cc_to_vclock(d) container_of((d), struct ptp_vclock, cc) +#define dw_to_vclock(d) container_of((d), struct ptp_vclock, refresh_work) + +struct ptp_vclock { + struct ptp_clock *pclock; + struct ptp_clock_info info; + struct ptp_clock *clock; + struct cyclecounter cc; + struct timecounter tc; + spinlock_t lock; /* protects tc/cc */ +}; + /* * The function queue_cnt() is safe for readers to call without * holding q->lock. Readers use this function to verify that the queue @@ -89,4 +102,6 @@ extern const struct attribute_group *ptp_groups[]; int ptp_populate_pin_groups(struct ptp_clock *ptp); void ptp_cleanup_pin_groups(struct ptp_clock *ptp); +struct ptp_vclock *ptp_vclock_register(struct ptp_clock *pclock); +void ptp_vclock_unregister(struct ptp_vclock *vclock); #endif diff --git a/drivers/ptp/ptp_vclock.c b/drivers/ptp/ptp_vclock.c new file mode 100644 index 000000000000..fc9205cc504d --- /dev/null +++ b/drivers/ptp/ptp_vclock.c @@ -0,0 +1,150 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * PTP virtual clock driver + * + * Copyright 2021 NXP + */ +#include +#include "ptp_private.h" + +#define PTP_VCLOCK_CC_SHIFT 31 +#define PTP_VCLOCK_CC_MULT (1 << PTP_VCLOCK_CC_SHIFT) +#define PTP_VCLOCK_FADJ_SHIFT 9 +#define PTP_VCLOCK_FADJ_DENOMINATOR 15625ULL +#define PTP_VCLOCK_REFRESH_INTERVAL (HZ * 2) + +static int ptp_vclock_adjfine(struct ptp_clock_info *ptp, long scaled_ppm) +{ + struct ptp_vclock *vclock = info_to_vclock(ptp); + unsigned long flags; + s64 adj; + + adj = (s64)scaled_ppm << PTP_VCLOCK_FADJ_SHIFT; + adj = div_s64(adj, PTP_VCLOCK_FADJ_DENOMINATOR); + + spin_lock_irqsave(&vclock->lock, flags); + timecounter_read(&vclock->tc); + vclock->cc.mult = PTP_VCLOCK_CC_MULT + adj; + spin_unlock_irqrestore(&vclock->lock, flags); + + return 0; +} + +static int ptp_vclock_adjtime(struct ptp_clock_info *ptp, s64 delta) +{ + struct ptp_vclock *vclock = info_to_vclock(ptp); + unsigned long flags; + + spin_lock_irqsave(&vclock->lock, flags); + timecounter_adjtime(&vclock->tc, delta); + spin_unlock_irqrestore(&vclock->lock, flags); + + return 0; +} + +static int ptp_vclock_gettime(struct ptp_clock_info *ptp, + struct timespec64 *ts) +{ + struct ptp_vclock *vclock = info_to_vclock(ptp); + unsigned long flags; + u64 ns; + + spin_lock_irqsave(&vclock->lock, flags); + ns = timecounter_read(&vclock->tc); + spin_unlock_irqrestore(&vclock->lock, flags); + *ts = ns_to_timespec64(ns); + + return 0; +} + +static int ptp_vclock_settime(struct ptp_clock_info *ptp, + const struct timespec64 *ts) +{ + struct ptp_vclock *vclock = info_to_vclock(ptp); + u64 ns = timespec64_to_ns(ts); + unsigned long flags; + + spin_lock_irqsave(&vclock->lock, flags); + timecounter_init(&vclock->tc, &vclock->cc, ns); + spin_unlock_irqrestore(&vclock->lock, flags); + + return 0; +} + +static long ptp_vclock_refresh(struct ptp_clock_info *ptp) +{ + struct ptp_vclock *vclock = info_to_vclock(ptp); + struct timespec64 ts; + + ptp_vclock_gettime(&vclock->info, &ts); + + return PTP_VCLOCK_REFRESH_INTERVAL; +} + +static const struct ptp_clock_info ptp_vclock_info = { + .owner = THIS_MODULE, + .name = "ptp virtual clock", + /* The maximum ppb value that long scaled_ppm can support */ + .max_adj = 32767999, + .adjfine = ptp_vclock_adjfine, + .adjtime = ptp_vclock_adjtime, + .gettime64 = ptp_vclock_gettime, + .settime64 = ptp_vclock_settime, + .do_aux_work = ptp_vclock_refresh, +}; + +static u64 ptp_vclock_read(const struct cyclecounter *cc) +{ + struct ptp_vclock *vclock = cc_to_vclock(cc); + struct ptp_clock *ptp = vclock->pclock; + struct timespec64 ts = {}; + + if (ptp->info->gettimex64) + ptp->info->gettimex64(ptp->info, &ts, NULL); + else + ptp->info->gettime64(ptp->info, &ts); + + return timespec64_to_ns(&ts); +} + +static const struct cyclecounter ptp_vclock_cc = { + .read = ptp_vclock_read, + .mask = CYCLECOUNTER_MASK(32), + .mult = PTP_VCLOCK_CC_MULT, + .shift = PTP_VCLOCK_CC_SHIFT, +}; + +struct ptp_vclock *ptp_vclock_register(struct ptp_clock *pclock) +{ + struct ptp_vclock *vclock; + + vclock = kzalloc(sizeof(*vclock), GFP_KERNEL); + if (!vclock) + return NULL; + + vclock->pclock = pclock; + vclock->info = ptp_vclock_info; + vclock->cc = ptp_vclock_cc; + + snprintf(vclock->info.name, PTP_CLOCK_NAME_LEN, "ptp%d_virt", + pclock->index); + + spin_lock_init(&vclock->lock); + + vclock->clock = ptp_clock_register(&vclock->info, &pclock->dev); + if (IS_ERR_OR_NULL(vclock->clock)) { + kfree(vclock); + return NULL; + } + + timecounter_init(&vclock->tc, &vclock->cc, 0); + ptp_schedule_worker(vclock->clock, PTP_VCLOCK_REFRESH_INTERVAL); + + return vclock; +} + +void ptp_vclock_unregister(struct ptp_vclock *vclock) +{ + ptp_clock_unregister(vclock->clock); + kfree(vclock); +} diff --git a/include/linux/ptp_clock_kernel.h b/include/linux/ptp_clock_kernel.h index aba237c0b3a2..b6fb771ee524 100644 --- a/include/linux/ptp_clock_kernel.h +++ b/include/linux/ptp_clock_kernel.h @@ -11,7 +11,9 @@ #include #include #include +#include +#define PTP_CLOCK_NAME_LEN 32 /** * struct ptp_clock_request - request PTP clock event * @@ -134,7 +136,7 @@ struct ptp_system_timestamp { struct ptp_clock_info { struct module *owner; - char name[16]; + char name[PTP_CLOCK_NAME_LEN]; s32 max_adj; int n_alarm; int n_ext_ts;