From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 7D3C4CF31B8 for ; Wed, 19 Nov 2025 12:25:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=VbfUzPP7zlxorBSwkb/tindr2DcdCyfvNDrhLE3X0oQ=; b=0zQnIvTpZifjr9af3iIomtRn9P usri8XCq4n6jb8WzU++Gw4MxgzGjT6PwXFGBp4i3eRWWPeR1wZgnghZbLzwVl4nqRx16zE6rD6Le4 mLInivr94b3PwdURp3L1ocYnfQqcLG3DfiI3R6xbr4mZu4oonUiUChrKGbWYjsHPkuU/NDssEweVE FcQN6Cq/RdRYvQAQiURVezmj61lVGUKpXZ3JZCNf9/qYenDc9uMzuyi8ivZxg7uJgNAyzPYqMD5qJ VLXL7XBKXCefjzvDQpWKnuYuE1GKXgXHcOQm4d4gmmWRIZKtE9WnaDansRfasXjIH8PXO1Xxa6DDD PXcx2rRA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vLhFE-000000037qG-3pUi; Wed, 19 Nov 2025 12:25:08 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vLhF2-000000037fl-47LP for linux-arm-kernel@lists.infradead.org; Wed, 19 Nov 2025 12:25:02 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id CE442169C; Wed, 19 Nov 2025 04:24:48 -0800 (PST) Received: from e134344.cambridge.arm.com (e134344.arm.com [10.1.196.46]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 1B1383F740; Wed, 19 Nov 2025 04:24:50 -0800 (PST) From: Ben Horgan To: james.morse@arm.com Cc: amitsinght@marvell.com, baisheng.gao@unisoc.com, baolin.wang@linux.alibaba.com, bobo.shaobowang@huawei.com, carl@os.amperecomputing.com, catalin.marinas@arm.com, dakr@kernel.org, dave.martin@arm.com, david@redhat.com, dfustini@baylibre.com, fenghuay@nvidia.com, gregkh@linuxfoundation.org, gshan@redhat.com, guohanjun@huawei.com, jeremy.linton@arm.com, jonathan.cameron@huawei.com, kobak@nvidia.com, lcherian@marvell.com, lenb@kernel.org, linux-acpi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, lpieralisi@kernel.org, peternewman@google.com, quic_jiles@quicinc.com, rafael@kernel.org, robh@kernel.org, rohit.mathew@arm.com, scott@os.amperecomputing.com, sdonthineni@nvidia.com, sudeep.holla@arm.com, tan.shaopeng@fujitsu.com, will@kernel.org, xhao@linux.alibaba.com, reinette.chatre@intel.com, Dave Martin , Shaopeng Tan , Zeng Heng , Ben Horgan Subject: [PATCH v6 16/34] arm_mpam: Probe the hardware features resctrl supports Date: Wed, 19 Nov 2025 12:22:46 +0000 Message-ID: <20251119122305.302149-17-ben.horgan@arm.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20251119122305.302149-1-ben.horgan@arm.com> References: <20251119122305.302149-1-ben.horgan@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20251119_042457_207244_21C7A98E X-CRM114-Status: GOOD ( 19.92 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: James Morse Expand the probing support with the control and monitor types we can use with resctrl. CC: Dave Martin Signed-off-by: James Morse Reviewed-by: Jonathan Cameron Reviewed-by: Fenghua Yu Reviewed-by: Gavin Shan Reviewed-by: Shaopeng Tan Tested-by: Fenghua Yu Tested-by: Shaopeng Tan Tested-by: Peter Newman Tested-by: Carl Worth Tested-by: Gavin Shan Tested-by: Zeng Heng Tested-by: Hanjun Guo Signed-off-by: Ben Horgan --- Changes since v3: Drop the =0 in the enum (Jonathan) --- drivers/resctrl/mpam_devices.c | 149 ++++++++++++++++++++++++++++++++ drivers/resctrl/mpam_internal.h | 33 +++++++ 2 files changed, 182 insertions(+) diff --git a/drivers/resctrl/mpam_devices.c b/drivers/resctrl/mpam_devices.c index dcbc9cf5581d..ff561a08cd0d 100644 --- a/drivers/resctrl/mpam_devices.c +++ b/drivers/resctrl/mpam_devices.c @@ -170,6 +170,22 @@ static inline void _mpam_write_partsel_reg(struct mpam_msc *msc, u16 reg, u32 va #define mpam_write_partsel_reg(msc, reg, val) _mpam_write_partsel_reg(msc, MPAMCFG_##reg, val) +static inline u32 _mpam_read_monsel_reg(struct mpam_msc *msc, u16 reg) +{ + mpam_mon_sel_lock_held(msc); + return __mpam_read_reg(msc, reg); +} + +#define mpam_read_monsel_reg(msc, reg) _mpam_read_monsel_reg(msc, MSMON_##reg) + +static inline void _mpam_write_monsel_reg(struct mpam_msc *msc, u16 reg, u32 val) +{ + mpam_mon_sel_lock_held(msc); + __mpam_write_reg(msc, reg, val); +} + +#define mpam_write_monsel_reg(msc, reg, val) _mpam_write_monsel_reg(msc, MSMON_##reg, val) + static u64 mpam_msc_read_idr(struct mpam_msc *msc) { u64 idr_high = 0, idr_low; @@ -548,6 +564,133 @@ static struct mpam_msc_ris *mpam_get_or_create_ris(struct mpam_msc *msc, return ERR_PTR(-ENOENT); } +/* + * IHI009A.a has this nugget: "If a monitor does not support automatic behaviour + * of NRDY, software can use this bit for any purpose" - so hardware might not + * implement this - but it isn't RES0. + * + * Try and see what values stick in this bit. If we can write either value, + * its probably not implemented by hardware. + */ +static bool _mpam_ris_hw_probe_hw_nrdy(struct mpam_msc_ris *ris, u32 mon_reg) +{ + u32 now; + u64 mon_sel; + bool can_set, can_clear; + struct mpam_msc *msc = ris->vmsc->msc; + + if (WARN_ON_ONCE(!mpam_mon_sel_lock(msc))) + return false; + + mon_sel = FIELD_PREP(MSMON_CFG_MON_SEL_MON_SEL, 0) | + FIELD_PREP(MSMON_CFG_MON_SEL_RIS, ris->ris_idx); + _mpam_write_monsel_reg(msc, mon_reg, mon_sel); + + _mpam_write_monsel_reg(msc, mon_reg, MSMON___NRDY); + now = _mpam_read_monsel_reg(msc, mon_reg); + can_set = now & MSMON___NRDY; + + _mpam_write_monsel_reg(msc, mon_reg, 0); + now = _mpam_read_monsel_reg(msc, mon_reg); + can_clear = !(now & MSMON___NRDY); + mpam_mon_sel_unlock(msc); + + return (!can_set || !can_clear); +} + +#define mpam_ris_hw_probe_hw_nrdy(_ris, _mon_reg) \ + _mpam_ris_hw_probe_hw_nrdy(_ris, MSMON_##_mon_reg) + +static void mpam_ris_hw_probe(struct mpam_msc_ris *ris) +{ + int err; + struct mpam_msc *msc = ris->vmsc->msc; + struct device *dev = &msc->pdev->dev; + struct mpam_props *props = &ris->props; + + lockdep_assert_held(&msc->probe_lock); + lockdep_assert_held(&msc->part_sel_lock); + + /* Cache Portion partitioning */ + if (FIELD_GET(MPAMF_IDR_HAS_CPOR_PART, ris->idr)) { + u32 cpor_features = mpam_read_partsel_reg(msc, CPOR_IDR); + + props->cpbm_wd = FIELD_GET(MPAMF_CPOR_IDR_CPBM_WD, cpor_features); + if (props->cpbm_wd) + mpam_set_feature(mpam_feat_cpor_part, props); + } + + /* Memory bandwidth partitioning */ + if (FIELD_GET(MPAMF_IDR_HAS_MBW_PART, ris->idr)) { + u32 mbw_features = mpam_read_partsel_reg(msc, MBW_IDR); + + /* portion bitmap resolution */ + props->mbw_pbm_bits = FIELD_GET(MPAMF_MBW_IDR_BWPBM_WD, mbw_features); + if (props->mbw_pbm_bits && + FIELD_GET(MPAMF_MBW_IDR_HAS_PBM, mbw_features)) + mpam_set_feature(mpam_feat_mbw_part, props); + + props->bwa_wd = FIELD_GET(MPAMF_MBW_IDR_BWA_WD, mbw_features); + if (props->bwa_wd && FIELD_GET(MPAMF_MBW_IDR_HAS_MAX, mbw_features)) + mpam_set_feature(mpam_feat_mbw_max, props); + } + + /* Performance Monitoring */ + if (FIELD_GET(MPAMF_IDR_HAS_MSMON, ris->idr)) { + u32 msmon_features = mpam_read_partsel_reg(msc, MSMON_IDR); + + /* + * If the firmware max-nrdy-us property is missing, the + * CSU counters can't be used. Should we wait forever? + */ + err = device_property_read_u32(&msc->pdev->dev, + "arm,not-ready-us", + &msc->nrdy_usec); + + if (FIELD_GET(MPAMF_MSMON_IDR_MSMON_CSU, msmon_features)) { + u32 csumonidr; + + csumonidr = mpam_read_partsel_reg(msc, CSUMON_IDR); + props->num_csu_mon = FIELD_GET(MPAMF_CSUMON_IDR_NUM_MON, csumonidr); + if (props->num_csu_mon) { + bool hw_managed; + + mpam_set_feature(mpam_feat_msmon_csu, props); + + /* Is NRDY hardware managed? */ + hw_managed = mpam_ris_hw_probe_hw_nrdy(ris, CSU); + if (hw_managed) + mpam_set_feature(mpam_feat_msmon_csu_hw_nrdy, props); + } + + /* + * Accept the missing firmware property if NRDY appears + * un-implemented. + */ + if (err && mpam_has_feature(mpam_feat_msmon_csu_hw_nrdy, props)) + dev_err_once(dev, "Counters are not usable because not-ready timeout was not provided by firmware."); + } + if (FIELD_GET(MPAMF_MSMON_IDR_MSMON_MBWU, msmon_features)) { + bool hw_managed; + u32 mbwumon_idr = mpam_read_partsel_reg(msc, MBWUMON_IDR); + + props->num_mbwu_mon = FIELD_GET(MPAMF_MBWUMON_IDR_NUM_MON, mbwumon_idr); + if (props->num_mbwu_mon) + mpam_set_feature(mpam_feat_msmon_mbwu, props); + + /* Is NRDY hardware managed? */ + hw_managed = mpam_ris_hw_probe_hw_nrdy(ris, MBWU); + if (hw_managed) + mpam_set_feature(mpam_feat_msmon_mbwu_hw_nrdy, props); + + /* + * Don't warn about any missing firmware property for + * MBWU NRDY - it doesn't make any sense! + */ + } + } +} + static int mpam_msc_hw_probe(struct mpam_msc *msc) { u64 idr; @@ -591,6 +734,12 @@ static int mpam_msc_hw_probe(struct mpam_msc *msc) mutex_unlock(&mpam_list_lock); if (IS_ERR(ris)) return PTR_ERR(ris); + ris->idr = idr; + + mutex_lock(&msc->part_sel_lock); + __mpam_part_sel(ris_idx, 0, msc); + mpam_ris_hw_probe(ris); + mutex_unlock(&msc->part_sel_lock); } spin_lock(&partid_max_lock); diff --git a/drivers/resctrl/mpam_internal.h b/drivers/resctrl/mpam_internal.h index 97f02cf92d7a..cdaa019367e9 100644 --- a/drivers/resctrl/mpam_internal.h +++ b/drivers/resctrl/mpam_internal.h @@ -5,12 +5,14 @@ #define MPAM_INTERNAL_H #include +#include #include #include #include #include #include #include +#include #include #define MPAM_MSC_MAX_NUM_RIS 16 @@ -112,6 +114,33 @@ static inline void mpam_mon_sel_lock_init(struct mpam_msc *msc) raw_spin_lock_init(&msc->_mon_sel_lock); } +/* Bits for mpam features bitmaps */ +enum mpam_device_features { + mpam_feat_cpor_part, + mpam_feat_mbw_part, + mpam_feat_mbw_min, + mpam_feat_mbw_max, + mpam_feat_msmon, + mpam_feat_msmon_csu, + mpam_feat_msmon_csu_hw_nrdy, + mpam_feat_msmon_mbwu, + mpam_feat_msmon_mbwu_hw_nrdy, + MPAM_FEATURE_LAST +}; + +struct mpam_props { + DECLARE_BITMAP(features, MPAM_FEATURE_LAST); + + u16 cpbm_wd; + u16 mbw_pbm_bits; + u16 bwa_wd; + u16 num_csu_mon; + u16 num_mbwu_mon; +}; + +#define mpam_has_feature(_feat, x) test_bit(_feat, (x)->features) +#define mpam_set_feature(_feat, x) set_bit(_feat, (x)->features) + struct mpam_class { /* mpam_components in this class */ struct list_head components; @@ -151,6 +180,8 @@ struct mpam_vmsc { /* mpam_msc_ris in this vmsc */ struct list_head ris; + struct mpam_props props; + /* All RIS in this vMSC are members of this MSC */ struct mpam_msc *msc; @@ -162,6 +193,8 @@ struct mpam_vmsc { struct mpam_msc_ris { u8 ris_idx; + u64 idr; + struct mpam_props props; cpumask_t affinity; -- 2.43.0