From patchwork Wed Jan 17 14:26:00 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pavan Nikhilesh Bhagavatula X-Patchwork-Id: 135929 Return-Path: X-Original-To: patchwork@inbox.dpdk.org Delivered-To: patchwork@inbox.dpdk.org Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id 2715A438EF; Wed, 17 Jan 2024 15:26:13 +0100 (CET) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 98B4B406B4; Wed, 17 Jan 2024 15:26:12 +0100 (CET) Received: from mx0b-0016f401.pphosted.com (mx0a-0016f401.pphosted.com [67.231.148.174]) by mails.dpdk.org (Postfix) with ESMTP id 5A7F74025E for ; Wed, 17 Jan 2024 15:26:11 +0100 (CET) Received: from pps.filterd (m0045849.ppops.net [127.0.0.1]) by mx0a-0016f401.pphosted.com (8.17.1.24/8.17.1.24) with ESMTP id 40H7jo71029521 for ; Wed, 17 Jan 2024 06:26:10 -0800 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=marvell.com; h= from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding:content-type; s= pfpt0220; bh=Mdma5MllGwJPnMIs7f35okkj03ML73NlOpq0flkq3ME=; b=Qu+ cFp0Iknsd8xHpnoiQ1xXKymSXIimECnTvfsVTQx5/6zKDvI1im4WNewCG+ilZcAB 6p7cuQcIMeO8pyPFc5bZC1dwiVTikp6MUt9LKeDPtexwgM90Ys5e6xEt+19OKTfC 7G01ilyMl33VGsWxi6kcHxcx7cRFqdugxPrAXxyaNv3Kt7fPs0nv2iPttXTSQ1JW GImEjAvsVB1fWeWVbOT1t5q9ab50CTTCx43akUhBh6S5nYAOB191JNj/7sA0PdP+ u/6g8DTmEvue0x+okQrJjkSuafFlm0iN8roOTV8SE8QnzYOxJvheUd0xEktsb0wJ CcVD2lfBU82WaiWTjxw== Received: from dc5-exch01.marvell.com ([199.233.59.181]) by mx0a-0016f401.pphosted.com (PPS) with ESMTPS id 3vpask96k3-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-SHA384 bits=256 verify=NOT) for ; Wed, 17 Jan 2024 06:26:10 -0800 (PST) Received: from DC5-EXCH01.marvell.com (10.69.176.38) by DC5-EXCH01.marvell.com (10.69.176.38) with Microsoft SMTP Server (TLS) id 15.0.1497.48; Wed, 17 Jan 2024 06:26:08 -0800 Received: from maili.marvell.com (10.69.176.80) by DC5-EXCH01.marvell.com (10.69.176.38) with Microsoft SMTP Server id 15.0.1497.48 via Frontend Transport; Wed, 17 Jan 2024 06:26:08 -0800 Received: from MININT-80QBFE8.corp.innovium.com (MININT-80QBFE8.marvell.com [10.28.164.106]) by maili.marvell.com (Postfix) with ESMTP id 95BB85B6932; Wed, 17 Jan 2024 06:26:06 -0800 (PST) From: To: , Pavan Nikhilesh , "Shijith Thotton" CC: Subject: [PATCH v2 2/2] event/cnxk: use WFE LDP loop for getwork routine Date: Wed, 17 Jan 2024 19:56:00 +0530 Message-ID: <20240117142600.1889-2-pbhagavatula@marvell.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20240117142600.1889-1-pbhagavatula@marvell.com> References: <20240104193633.2264-1-pbhagavatula@marvell.com> <20240117142600.1889-1-pbhagavatula@marvell.com> MIME-Version: 1.0 X-Proofpoint-ORIG-GUID: eyrKAH8cOk4DzNNKEn-S3-h7V4MJsgzY X-Proofpoint-GUID: eyrKAH8cOk4DzNNKEn-S3-h7V4MJsgzY X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.997,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2024-01-17_08,2024-01-17_01,2023-05-22_02 X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org From: Pavan Nikhilesh Use WFE LDP loop while polling for GETWORK completion for better power savings. Disabled by default and can be enabled by configuring meson with -Dc_args='-DRTE_ARM_USE_WFE'. Signed-off-by: Pavan Nikhilesh --- doc/guides/eventdevs/cnxk.rst | 9 ++++++ drivers/event/cnxk/cn10k_worker.h | 52 +++++++++++++++++++++++++------ 2 files changed, 52 insertions(+), 9 deletions(-) diff --git a/doc/guides/eventdevs/cnxk.rst b/doc/guides/eventdevs/cnxk.rst index cccb8a0304..04f5b5025b 100644 --- a/doc/guides/eventdevs/cnxk.rst +++ b/doc/guides/eventdevs/cnxk.rst @@ -198,6 +198,15 @@ Runtime Config Options -a 0002:0e:00.0,tim_eclk_freq=122880000-1000000000-0 +Power Savings on CN10K +---------------------- + +ARM cores can additionally use WFE when polling for transactions on SSO bus +to save power i.e., in the event dequeue call ARM core can enter WFE and exit +when either work has been scheduled or dequeue timeout has reached. +This can be enabled by configuring meson with the following option +``-Dc_args='-DRTE_ARM_USE_WFE'``. + Debugging Options ----------------- diff --git a/drivers/event/cnxk/cn10k_worker.h b/drivers/event/cnxk/cn10k_worker.h index 8aa916fa12..92d5190842 100644 --- a/drivers/event/cnxk/cn10k_worker.h +++ b/drivers/event/cnxk/cn10k_worker.h @@ -250,23 +250,57 @@ cn10k_sso_hws_get_work(struct cn10k_sso_hws *ws, struct rte_event *ev, gw.get_work = ws->gw_wdata; #if defined(RTE_ARCH_ARM64) -#if !defined(__clang__) - asm volatile( - PLT_CPU_FEATURE_PREAMBLE - "caspal %[wdata], %H[wdata], %[wdata], %H[wdata], [%[gw_loc]]\n" - : [wdata] "+r"(gw.get_work) - : [gw_loc] "r"(ws->base + SSOW_LF_GWS_OP_GET_WORK0) - : "memory"); -#else +#if defined(__clang__) register uint64_t x0 __asm("x0") = (uint64_t)gw.u64[0]; register uint64_t x1 __asm("x1") = (uint64_t)gw.u64[1]; +#if defined(RTE_ARM_USE_WFE) + plt_write64(gw.u64[0], ws->base + SSOW_LF_GWS_OP_GET_WORK0); + asm volatile(PLT_CPU_FEATURE_PREAMBLE + " ldp %[x0], %[x1], [%[tag_loc]] \n" + " tbz %[x0], %[pend_gw], done%= \n" + " sevl \n" + "rty%=: wfe \n" + " ldp %[x0], %[x1], [%[tag_loc]] \n" + " tbnz %[x0], %[pend_gw], rty%= \n" + "done%=: \n" + " dmb ld \n" + : [x0] "+r" (x0), [x1] "+r" (x1) + : [tag_loc] "r"(ws->base + SSOW_LF_GWS_WQE0), + [pend_gw] "i"(SSOW_LF_GWS_TAG_PEND_GET_WORK_BIT) + : "memory"); +#else asm volatile(".arch armv8-a+lse\n" "caspal %[x0], %[x1], %[x0], %[x1], [%[dst]]\n" - : [x0] "+r"(x0), [x1] "+r"(x1) + : [x0] "+r" (x0), [x1] "+r" (x1) : [dst] "r"(ws->base + SSOW_LF_GWS_OP_GET_WORK0) : "memory"); +#endif gw.u64[0] = x0; gw.u64[1] = x1; +#else +#if defined(RTE_ARM_USE_WFE) + plt_write64(gw.u64[0], ws->base + SSOW_LF_GWS_OP_GET_WORK0); + asm volatile(PLT_CPU_FEATURE_PREAMBLE + " ldp %[wdata], %H[wdata], [%[tag_loc]] \n" + " tbz %[wdata], %[pend_gw], done%= \n" + " sevl \n" + "rty%=: wfe \n" + " ldp %[wdata], %H[wdata], [%[tag_loc]] \n" + " tbnz %[wdata], %[pend_gw], rty%= \n" + "done%=: \n" + " dmb ld \n" + : [wdata] "=&r"(gw.get_work) + : [tag_loc] "r"(ws->base + SSOW_LF_GWS_WQE0), + [pend_gw] "i"(SSOW_LF_GWS_TAG_PEND_GET_WORK_BIT) + : "memory"); +#else + asm volatile( + PLT_CPU_FEATURE_PREAMBLE + "caspal %[wdata], %H[wdata], %[wdata], %H[wdata], [%[gw_loc]]\n" + : [wdata] "+r"(gw.get_work) + : [gw_loc] "r"(ws->base + SSOW_LF_GWS_OP_GET_WORK0) + : "memory"); +#endif #endif #else plt_write64(gw.u64[0], ws->base + SSOW_LF_GWS_OP_GET_WORK0);