From patchwork Tue Mar 19 13:05:37 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "D, Lakshmi Sowjanya" X-Patchwork-Id: 13596642 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.16]) (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 1A94F4085D; Tue, 19 Mar 2024 13:06:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.16 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710853565; cv=none; b=MgYsVnXzotip71BgwUn+BPqTJJs6VFvZVUFHrl6h1IkPpbjKa+2/TrYbEPWKcmkTdolk01QgMbFRsoQVF1Losk3v4xfZRgSj8RPWptZhYp76NCTDlwjdusIM0FX0nGLJQbc3KoK2tfOGSK4wobZElYEKoAoOdAWQMsEG8jDBY2E= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710853565; c=relaxed/simple; bh=+S2MewHLlenRx3Semp3QRkK4+r3hJzwDF86OL9/JXV4=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=c23qfSzzEuNqVRbRcTnGhzvA+6jAChm47l0GO/IZMjXuK7K5vGuYV+YywpJJ4IdUYYnV2e/MY7FP3sAcY2ZJB6n2xuiJ/sJzmacYa7cwQhds8pWXmNLi3x+1Aevdffa8yXhZQEXDTrWvx6i43tEOsV4BqEyWeSdPJd02FmftplA= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=H1IRijaY; arc=none smtp.client-ip=198.175.65.16 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="H1IRijaY" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1710853563; x=1742389563; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=+S2MewHLlenRx3Semp3QRkK4+r3hJzwDF86OL9/JXV4=; b=H1IRijaYziPgzjUGPmsNqmJjaBwYjMq8Ljf/7pCAKW6H4ESta6Xa15qq mF6Vx1PxHuBXaMiEDXQKiKK0fVXC7en0Sc/uzt82yDKGk7iEMqySxuyC0 a/sNZvFYq5c+i6m9mdRdP+M5X4LebzTC+PxyGbYK31x2khiltcVNjcBcE 2l9yiODn0tAAW9J7f3sY02FHTh0UOudi0dkAB20h978Nn/OXkx8nGlJXf Tsxc2YJSWp4U3vAbFSAt34pJycikqAhr7rp9soWSX2tzipNni0GGVUovV y6g92PlLoZ/xbkR7wQ4XrpMRmRbOlUiiUh5ukydNzcXmARUI7vWtrtMGE A==; X-IronPort-AV: E=McAfee;i="6600,9927,11017"; a="5842882" X-IronPort-AV: E=Sophos;i="6.07,137,1708416000"; d="scan'208";a="5842882" Received: from fmviesa001.fm.intel.com ([10.60.135.141]) by orvoesa108.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 19 Mar 2024 06:06:03 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.07,137,1708416000"; d="scan'208";a="44883169" Received: from inlubt0316.iind.intel.com ([10.191.20.213]) by fmviesa001.fm.intel.com with ESMTP; 19 Mar 2024 06:05:55 -0700 From: lakshmi.sowjanya.d@intel.com To: tglx@linutronix.de, jstultz@google.com, giometti@enneenne.com, corbet@lwn.net, linux-kernel@vger.kernel.org Cc: x86@kernel.org, netdev@vger.kernel.org, linux-doc@vger.kernel.org, intel-wired-lan@lists.osuosl.org, andriy.shevchenko@linux.intel.com, eddie.dong@intel.com, christopher.s.hall@intel.com, jesse.brandeburg@intel.com, davem@davemloft.net, alexandre.torgue@foss.st.com, joabreu@synopsys.com, mcoquelin.stm32@gmail.com, perex@perex.cz, linux-sound@vger.kernel.org, anthony.l.nguyen@intel.com, peter.hilber@opensynergy.com, pandith.n@intel.com, mallikarjunappa.sangannavar@intel.com, subramanian.mohan@intel.com, basavaraj.goudar@intel.com, thejesh.reddy.t.r@intel.com, lakshmi.sowjanya.d@intel.com Subject: [PATCH v5 01/11] x86/tsc: Add base clock properties in clocksource structure Date: Tue, 19 Mar 2024 18:35:37 +0530 Message-Id: <20240319130547.4195-2-lakshmi.sowjanya.d@intel.com> X-Mailer: git-send-email 2.35.3 In-Reply-To: <20240319130547.4195-1-lakshmi.sowjanya.d@intel.com> References: <20240319130547.4195-1-lakshmi.sowjanya.d@intel.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Lakshmi Sowjanya D Add base clock hardware abstraction in clocksource structure. Add clocksource ID for x86 ART(Always Running Timer). Co-developed-by: Thomas Gleixner Signed-off-by: Thomas Gleixner Co-developed-by: Christopher S. Hall Signed-off-by: Christopher S. Hall Signed-off-by: Lakshmi Sowjanya D --- arch/x86/kernel/tsc.c | 42 +++++++++++++++++++-------------- include/linux/clocksource.h | 27 +++++++++++++++++++++ include/linux/clocksource_ids.h | 1 + 3 files changed, 52 insertions(+), 18 deletions(-) diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c index 5a69a49acc96..45bf2f6d0ffa 100644 --- a/arch/x86/kernel/tsc.c +++ b/arch/x86/kernel/tsc.c @@ -50,9 +50,9 @@ int tsc_clocksource_reliable; static int __read_mostly tsc_force_recalibrate; -static u32 art_to_tsc_numerator; -static u32 art_to_tsc_denominator; -static u64 art_to_tsc_offset; +static struct clocksource_base art_base_clk = { + .id = CSID_X86_ART, +}; static bool have_art; struct cyc2ns { @@ -1074,7 +1074,7 @@ core_initcall(cpufreq_register_tsc_scaling); */ static void __init detect_art(void) { - unsigned int unused[2]; + unsigned int unused; if (boot_cpu_data.cpuid_level < ART_CPUID_LEAF) return; @@ -1089,13 +1089,14 @@ static void __init detect_art(void) tsc_async_resets) return; - cpuid(ART_CPUID_LEAF, &art_to_tsc_denominator, - &art_to_tsc_numerator, unused, unused+1); + cpuid(ART_CPUID_LEAF, &art_base_clk.denominator, + &art_base_clk.numerator, &art_base_clk.freq_khz, &unused); - if (art_to_tsc_denominator < ART_MIN_DENOMINATOR) + art_base_clk.freq_khz /= KHZ; + if (art_base_clk.denominator < ART_MIN_DENOMINATOR) return; - rdmsrl(MSR_IA32_TSC_ADJUST, art_to_tsc_offset); + rdmsrl(MSR_IA32_TSC_ADJUST, art_base_clk.offset); /* Make this sticky over multiple CPU init calls */ setup_force_cpu_cap(X86_FEATURE_ART); @@ -1303,13 +1304,13 @@ struct system_counterval_t convert_art_to_tsc(u64 art) { u64 tmp, res, rem; - rem = do_div(art, art_to_tsc_denominator); + rem = do_div(art, art_base_clk.denominator); - res = art * art_to_tsc_numerator; - tmp = rem * art_to_tsc_numerator; + res = art * art_base_clk.numerator; + tmp = rem * art_base_clk.numerator; - do_div(tmp, art_to_tsc_denominator); - res += tmp + art_to_tsc_offset; + do_div(tmp, art_base_clk.denominator); + res += tmp + art_base_clk.offset; return (struct system_counterval_t) { .cs_id = have_art ? CSID_X86_TSC : CSID_GENERIC, @@ -1356,7 +1357,6 @@ struct system_counterval_t convert_art_ns_to_tsc(u64 art_ns) } EXPORT_SYMBOL(convert_art_ns_to_tsc); - static void tsc_refine_calibration_work(struct work_struct *work); static DECLARE_DELAYED_WORK(tsc_irqwork, tsc_refine_calibration_work); /** @@ -1458,8 +1458,10 @@ static void tsc_refine_calibration_work(struct work_struct *work) if (tsc_unstable) goto unreg; - if (boot_cpu_has(X86_FEATURE_ART)) + if (boot_cpu_has(X86_FEATURE_ART)) { have_art = true; + clocksource_tsc.base = &art_base_clk; + } clocksource_register_khz(&clocksource_tsc, tsc_khz); unreg: clocksource_unregister(&clocksource_tsc_early); @@ -1484,8 +1486,10 @@ static int __init init_tsc_clocksource(void) * the refined calibration and directly register it as a clocksource. */ if (boot_cpu_has(X86_FEATURE_TSC_KNOWN_FREQ)) { - if (boot_cpu_has(X86_FEATURE_ART)) + if (boot_cpu_has(X86_FEATURE_ART)) { have_art = true; + clocksource_tsc.base = &art_base_clk; + } clocksource_register_khz(&clocksource_tsc, tsc_khz); clocksource_unregister(&clocksource_tsc_early); @@ -1509,10 +1513,12 @@ static bool __init determine_cpu_tsc_frequencies(bool early) if (early) { cpu_khz = x86_platform.calibrate_cpu(); - if (tsc_early_khz) + if (tsc_early_khz) { tsc_khz = tsc_early_khz; - else + } else { tsc_khz = x86_platform.calibrate_tsc(); + clocksource_tsc.freq_khz = tsc_khz; + } } else { /* We should not be here with non-native cpu calibration */ WARN_ON(x86_platform.calibrate_cpu != native_calibrate_cpu); diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h index 0ad8b550bb4b..66a033bff17c 100644 --- a/include/linux/clocksource.h +++ b/include/linux/clocksource.h @@ -21,6 +21,7 @@ #include #include +struct clocksource_base; struct clocksource; struct module; @@ -48,6 +49,7 @@ struct module; * @archdata: Optional arch-specific data * @max_cycles: Maximum safe cycle value which won't overflow on * multiplication + * @freq_khz: Clocksource frequency in khz. * @name: Pointer to clocksource name * @list: List head for registration (internal) * @rating: Rating value for selection (higher is better) @@ -70,6 +72,8 @@ struct module; * validate the clocksource from which the snapshot was * taken. * @flags: Flags describing special properties + * @base: Hardware abstraction for clock on which a clocksource + * is based * @enable: Optional function to enable the clocksource * @disable: Optional function to disable the clocksource * @suspend: Optional suspend function for the clocksource @@ -105,12 +109,14 @@ struct clocksource { struct arch_clocksource_data archdata; #endif u64 max_cycles; + u32 freq_khz; const char *name; struct list_head list; int rating; enum clocksource_ids id; enum vdso_clock_mode vdso_clock_mode; unsigned long flags; + struct clocksource_base *base; int (*enable)(struct clocksource *cs); void (*disable)(struct clocksource *cs); @@ -306,4 +312,25 @@ static inline unsigned int clocksource_get_max_watchdog_retry(void) void clocksource_verify_percpu(struct clocksource *cs); +/** + * struct clocksource_base - hardware abstraction for clock on which a clocksource + * is based + * @id: Defaults to CSID_GENERIC. The id value is used for conversion + * functions which require that the current clocksource is based + * on a clocksource_base with a particular ID in certain snapshot + * functions to allow callers to validate the clocksource from + * which the snapshot was taken. + * @freq_khz: Nominal frequency of the base clock in kHz + * @offset: Offset between the base clock and the clocksource + * @numerator: Numerator of the clock ratio between base clock and the clocksource + * @denominator: Denominator of the clock ratio between base clock and the clocksource + */ +struct clocksource_base { + enum clocksource_ids id; + u32 freq_khz; + u64 offset; + u32 numerator; + u32 denominator; +}; + #endif /* _LINUX_CLOCKSOURCE_H */ diff --git a/include/linux/clocksource_ids.h b/include/linux/clocksource_ids.h index a4fa3436940c..2bb4d8c2f1b0 100644 --- a/include/linux/clocksource_ids.h +++ b/include/linux/clocksource_ids.h @@ -9,6 +9,7 @@ enum clocksource_ids { CSID_X86_TSC_EARLY, CSID_X86_TSC, CSID_X86_KVM_CLK, + CSID_X86_ART, CSID_MAX, };