From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx07-00178001.pphosted.com (mx07-00178001.pphosted.com [185.132.182.106]) (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 DFA132EE962; Tue, 22 Jul 2025 14:07:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.132.182.106 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753193247; cv=none; b=QaksPLqbDpV10wWZT3hY/mcZi5IhhikYb6zvvOg907ash4pBE78XubX/ksHiB1Or/L1WJ/XOhi3sPI35/aWslgo/zo8qZ+Z1/puqy+9e2ro5UiB9CEuIyw9LQuqbcFyIrB6TRiaRB+mmdjLCO8wsQRKHuQrzYOH84H0f4sqLRtY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753193247; c=relaxed/simple; bh=2uEtFVwi+wdX8OeRQHgPRlqO3x1jsKN8u5e4kKD7Awk=; h=From:Date:Subject:MIME-Version:Content-Type:Message-ID:References: In-Reply-To:To:CC; b=P8AlaWMneQAU/Wf8rOtx2vSORCVbU9nBV0gQ4zuqaiBCnW7WIrlK/MfKmJ4THECmyyLBnt/69PynNOEkpRoy6i5d3Ere/cHtc3P/SS16pmRV0a7Rr3bwEJcaL/XnkBPzZksSiky86LpwFk6kUShCbHJ4tENn8LofYVIyAX2CyEE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=foss.st.com; spf=pass smtp.mailfrom=foss.st.com; dkim=pass (2048-bit key) header.d=foss.st.com header.i=@foss.st.com header.b=gDYgEAXy; arc=none smtp.client-ip=185.132.182.106 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=foss.st.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=foss.st.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=foss.st.com header.i=@foss.st.com header.b="gDYgEAXy" Received: from pps.filterd (m0288072.ppops.net [127.0.0.1]) by mx07-00178001.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 56MD83Wd031012; Tue, 22 Jul 2025 16:07:07 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=foss.st.com; h= cc:content-transfer-encoding:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to; s=selector1; bh= W7lja2ibWXfiVo4eDJLx4tgeIggbs4JL9GjrFt29DoI=; b=gDYgEAXyBnH5FUUW i4fCuLDYToohHAmVr44V0KMTNF5T9Pg7wuuGuEF427HpDAO02apvXFgWVJ/A0kHJ mvkoudbS9QX1WQrA+8FGB3fevhzKyjrcVv4Di3/wqMLVUVUmJxuKtpYxqtwIExN9 F8zClTloDwK7g8OMhZjFFW9JW/GTBOgAVHDaIDXHCZ16AwLko6MtvZXaYr73dBCi cb2+WrY/qczgL1W23FNJewCrffI5J6PiScbCovV5dCdWUoQw0bayc+IECXrK468v uIka4ofR21VS1qUNi1f9SqbaOl7d5R87TeNO3mDxgtL+W+VZoFaKVfTjlQH6KK/z Pqea1A== Received: from beta.dmz-ap.st.com (beta.dmz-ap.st.com [138.198.100.35]) by mx07-00178001.pphosted.com (PPS) with ESMTPS id 4800skxykq-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 22 Jul 2025 16:07:07 +0200 (MEST) Received: from euls16034.sgp.st.com (euls16034.sgp.st.com [10.75.44.20]) by beta.dmz-ap.st.com (STMicroelectronics) with ESMTP id 0D5504004D; Tue, 22 Jul 2025 16:05:20 +0200 (CEST) Received: from Webmail-eu.st.com (shfdag1node2.st.com [10.75.129.70]) by euls16034.sgp.st.com (STMicroelectronics) with ESMTP id 3B9987A3203; Tue, 22 Jul 2025 16:03:59 +0200 (CEST) Received: from localhost (10.48.86.185) by SHFDAG1NODE2.st.com (10.75.129.70) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.39; Tue, 22 Jul 2025 16:03:58 +0200 From: =?utf-8?q?Cl=C3=A9ment_Le_Goffic?= Date: Tue, 22 Jul 2025 16:03:30 +0200 Subject: [PATCH v3 13/19] Documentation: perf: stm32: add ddrperfm support Precedence: bulk X-Mailing-List: linux-clk@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Message-ID: <20250722-ddrperfm-upstream-v3-13-7b7a4f3dc8a0@foss.st.com> References: <20250722-ddrperfm-upstream-v3-0-7b7a4f3dc8a0@foss.st.com> In-Reply-To: <20250722-ddrperfm-upstream-v3-0-7b7a4f3dc8a0@foss.st.com> To: Will Deacon , Mark Rutland , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Maxime Coquelin , Alexandre Torgue , Philipp Zabel , Jonathan Corbet , Gatien Chevallier , Michael Turquette , Stephen Boyd , Gabriel Fernandez , Krzysztof Kozlowski , Le Goffic , Julius Werner CC: , , , , , , , =?utf-8?q?Cl=C3=A9ment_Le_Goffic?= X-Mailer: b4 0.15-dev-8018a X-ClientProxiedBy: SHFCAS1NODE2.st.com (10.75.129.73) To SHFDAG1NODE2.st.com (10.75.129.70) X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1099,Hydra:6.1.9,FMLib:17.12.80.40 definitions=2025-07-22_02,2025-07-21_02,2025-03-28_01 The DDRPERFM is the DDR Performance Monitor embedded in STM32MPU SoC. This documentation introduces the DDRPERFM, the stm32-ddr-pmu driver supporting it and how to use it with the perf tool. Signed-off-by: Clément Le Goffic --- Documentation/admin-guide/perf/index.rst | 1 + Documentation/admin-guide/perf/stm32-ddr-pmu.rst | 86 ++++++++++++++++++++++++ 2 files changed, 87 insertions(+) diff --git a/Documentation/admin-guide/perf/index.rst b/Documentation/admin-guide/perf/index.rst index 072b510385c4..33aedc4ee5c3 100644 --- a/Documentation/admin-guide/perf/index.rst +++ b/Documentation/admin-guide/perf/index.rst @@ -29,3 +29,4 @@ Performance monitor support cxl ampere_cspmu mrvl-pem-pmu + stm32-ddr-pmu diff --git a/Documentation/admin-guide/perf/stm32-ddr-pmu.rst b/Documentation/admin-guide/perf/stm32-ddr-pmu.rst new file mode 100644 index 000000000000..5b02bf44dd7a --- /dev/null +++ b/Documentation/admin-guide/perf/stm32-ddr-pmu.rst @@ -0,0 +1,86 @@ +.. SPDX-License-Identifier: GPL-2.0 + +======================================== +STM32 DDR Performance Monitor (DDRPERFM) +======================================== + +The DDRPERFM is the DDR Performance Monitor embedded in STM32MPU SoC. +The DDR controller provides events to DDRPERFM, once selected they are counted in the DDRPERFM +peripheral. + +In MP1 family, the DDRPERFM is able to count 4 different events at the same time. +However, the 4 events must belong to the same set. +One hardware counter is dedicated to the time counter, `time_cnt`. + +In MP2 family, the DDRPERFM is able to select between 44 different DDR events. +As for MP1, there is a dedicated hardware counter for the time. +It is incremented every 4 DDR clock cycles. +All the other counters can be freely allocated to count any other DDR event. + +The stm32-ddr-pmu driver relies on the perf PMU framework to expose the counters via sysfs: + +On MP1: + + .. code-block:: bash + + $ ls /sys/bus/event_source/devices/stm32_ddr_pmu/events/ + cactive_ddrc perf_lpr_req_with_no_credit perf_op_is_wr + ctl_idle perf_lpr_xact_when_critical perf_selfresh_mode + dfi_lp_req perf_op_is_activate perf_wr_xact_when_critical + dfi_lp_req_cpy perf_op_is_enter_powerdown time_cnt + perf_hpr_req_with_no_credit perf_op_is_rd + perf_hpr_xact_when_critical perf_op_is_refresh + +On MP2: + + .. code-block:: bash + + $ ls /sys/bus/event_source/devices/stm32_ddr_pmu/events/ + dfi_is_act perf_hpr_req_with_nocredit perf_op_is_spec_ref + dfi_is_mpc perf_hpr_xact_when_critical perf_op_is_wr + dfi_is_mrr perf_lpr_req_with_nocredit perf_op_is_zqcal + dfi_is_mrw perf_lpr_xact_when_critical perf_rank + dfi_is_mwr perf_op_is_act perf_raw_hazard + dfi_is_mwra perf_op_is_crit_ref perf_rdwr_transitions + dfi_is_preab perf_op_is_enter_powdn perf_read_bypass + dfi_is_prepb perf_op_is_enter_selfref perf_war_hazard + dfi_is_rd perf_op_is_mwr perf_waw_hazard + dfi_is_rda perf_op_is_pre perf_window_limit_reached_rd + dfi_is_refab perf_op_is_pre_for_others perf_window_limit_reached_wr + dfi_is_refpb perf_op_is_pre_for_rdwr perf_wr_xact_when_critical + dfi_is_wr perf_op_is_rd time_cnt + dfi_is_wra perf_op_is_rd_activate + perf_act_bypass perf_op_is_ref + + +The perf PMU framework is usually invoked via the 'perf stat' tool. + + +Example: + + .. code-block:: bash + + $ perf stat --timeout 60000 -e stm32_ddr_pmu/dfi_is_act/,\ + > stm32_ddr_pmu/dfi_is_rd/,\ + > stm32_ddr_pmu/dfi_is_wr/,\ + > stm32_ddr_pmu/dfi_is_refab/,\ + > stm32_ddr_pmu/dfi_is_mrw/,\ + > stm32_ddr_pmu/dfi_is_rda/,\ + > stm32_ddr_pmu/dfi_is_wra/,\ + > stm32_ddr_pmu/dfi_is_mrr/,\ + > stm32_ddr_pmu/time_cnt/ \ + > -a sleep 5 + + Performance counter stats for 'system wide': + + 481025 stm32_ddr_pmu/dfi_is_act/ + 732166 stm32_ddr_pmu/dfi_is_rd/ + 144926 stm32_ddr_pmu/dfi_is_wr/ + 644154 stm32_ddr_pmu/dfi_is_refab/ + 0 stm32_ddr_pmu/dfi_is_mrw/ + 0 stm32_ddr_pmu/dfi_is_rda/ + 0 stm32_ddr_pmu/dfi_is_wra/ + 0 stm32_ddr_pmu/dfi_is_mrr/ + 752347686 stm32_ddr_pmu/time_cnt/ + + 5.014910750 seconds time elapsed -- 2.43.0