From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from pdx-out-007.esa.us-west-2.outbound.mail-perimeter.amazon.com (pdx-out-007.esa.us-west-2.outbound.mail-perimeter.amazon.com [52.34.181.151]) (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 3FD1B3783CB; Mon, 4 May 2026 13:39:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=52.34.181.151 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777901987; cv=none; b=pKQpaUlovs+dzWeCESUe+4M4I1JkfjXyyo42+G9DPZkfoDv+BelHc1s17idC7W1lUsbEK/cQLKD4tKw39W1mRKOtCbhvch4GmxnWx+ZzH+RUqjjwoSwiu+eOIgJP6RaLMURx4gn3aF6xvpYtyU21cPiri+dp+JnG9JlzvYfnVPY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777901987; c=relaxed/simple; bh=uKt6xa8IR7FtkbRoSAurvcw808TepNIpFvhgbskHwOk=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=DcE9ifs47L+01sAUhirJoGty0oBD9opRnIRDYh/KmOMBIvmxn8+5vCWJS+A38kpLqGuLsvhPg80uS+k42FhTrPL83CP+7x+y4khjn3aExINF7ythbMeD0juebKAtwKDPyeRsyo8woT4RdwZuarEPRGYTYL0brr97tVTz4HhFyxI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=amazon.com; spf=pass smtp.mailfrom=amazon.com; dkim=pass (2048-bit key) header.d=amazon.com header.i=@amazon.com header.b=rbi9Deia; arc=none smtp.client-ip=52.34.181.151 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=amazon.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=amazon.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=amazon.com header.i=@amazon.com header.b="rbi9Deia" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.com; i=@amazon.com; q=dns/txt; s=amazoncorp2; t=1777901983; x=1809437983; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=fNRJYDnePOIcF4F2ZoFB+uADc57hTs5TklnXfgahzhs=; b=rbi9DeiaSK8jCMfWA32MLq+ZfpuDclUokD2zgsL6emEpSW0gPGinyLIR 8q0zOC2s500C1dERxZgFTWQVElqEbxEsersidkOC35jC6D7MCY10dh0XR qw94vnTbECZesDlrGRq/D0JSFSwUuGQdtlJaycSgai2s4aAIpQ7ZlwRkh A30tuRYB7YXa2hBOd2dFYk61Z7SU6VKMTu8mq6vLnxoPCnLp5VtnuW6SF fk5lj/+kcOmW+s/WFzFbdsBrv0RvFkp726CVbloXdvZ5VyyLmaTjugze2 IjfLYA+A5WqJbrA/msG9eiKkYLqYHHD0lqa1qo68INgaWiDneUE3+yF49 A==; X-CSE-ConnectionGUID: VpwhKQgxQs6E7hUtzaK41A== X-CSE-MsgGUID: G1BeTpFTTBi1xtSzBRkZRg== X-IronPort-AV: E=Sophos;i="6.23,215,1770595200"; d="scan'208";a="18776025" Received: from ip-10-5-0-115.us-west-2.compute.internal (HELO smtpout.naws.us-west-2.prod.farcaster.email.amazon.dev) ([10.5.0.115]) by internal-pdx-out-007.esa.us-west-2.outbound.mail-perimeter.amazon.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 04 May 2026 13:39:27 +0000 Received: from EX19MTAUWA001.ant.amazon.com [205.251.233.182:2843] by smtpin.naws.us-west-2.prod.farcaster.email.amazon.dev [10.0.20.153:2525] with esmtp (Farcaster) id d69adaeb-c0a2-4473-9423-34e4046ac0ae; Mon, 4 May 2026 13:39:27 +0000 (UTC) X-Farcaster-Flow-ID: d69adaeb-c0a2-4473-9423-34e4046ac0ae Received: from EX19D001UWA001.ant.amazon.com (10.13.138.214) by EX19MTAUWA001.ant.amazon.com (10.250.64.218) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA) id 15.2.2562.37; Mon, 4 May 2026 13:39:27 +0000 Received: from dev-dsk-avivb-1b-e28f450e.eu-west-1.amazon.com (10.15.33.9) by EX19D001UWA001.ant.amazon.com (10.13.138.214) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA) id 15.2.2562.37; Mon, 4 May 2026 13:39:25 +0000 From: Aviv Bakal To: , , CC: , , , , Subject: [PATCH v2] perf/arm-cmn: Add workarounds for CMN-S3 on Graviton5 Date: Mon, 4 May 2026 16:39:23 +0300 Message-ID: <20260504133923.23373-1-avivb@amazon.com> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260503155118.16191-1-avivb@amazon.com> References: <20260503155118.16191-1-avivb@amazon.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain X-ClientProxiedBy: EX19D033UWC001.ant.amazon.com (10.13.139.218) To EX19D001UWA001.ant.amazon.com (10.13.138.214) Graviton5 uses a customised CMN-S3 implementation where certain discovery registers report zeroed fields. Add the following workarounds: - Introduce a dedicated ACPI HID to identify the Graviton5 CMN variant. - Derive the DTC domain from the XP node ID, since the unit info register reports it as zero. - Set the DTC logical ID from the computed domain ID, since the node info register's logical ID field is also zeroed. Signed-off-by: Aviv Bakal --- v2: - Use computed domain ID (xp->dtc) instead of XP logical ID for DTC logical ID assignment. drivers/perf/arm-cmn.c | 32 +++++++++++++++++++++++++++++++- 1 file changed, 31 insertions(+), 1 deletion(-) diff --git a/drivers/perf/arm-cmn.c b/drivers/perf/arm-cmn.c index f5305c8fdca4..8ee3f8638602 100644 --- a/drivers/perf/arm-cmn.c +++ b/drivers/perf/arm-cmn.c @@ -31,7 +31,8 @@ #define CMN_CHILD_NODE_ADDR GENMASK(29, 0) #define CMN_CHILD_NODE_EXTERNAL BIT(31) -#define CMN_MAX_DIMENSION 12 +/* Some implementations use a mesh larger than the architectural max of 12 */ +#define CMN_MAX_DIMENSION 14 #define CMN_MAX_XPS (CMN_MAX_DIMENSION * CMN_MAX_DIMENSION) #define CMN_MAX_DTMS (CMN_MAX_XPS + (CMN_MAX_DIMENSION - 1) * 4) @@ -214,6 +215,8 @@ enum cmn_part { PART_CMN700 = 0x43c, PART_CI700 = 0x43a, PART_CMN_S3 = 0x43e, + /* Synthetic part number, overridden to PART_CMN_S3 during discovery */ + PART_GRAVITON5 = 0xa5, }; /* CMN-600 r0px shouldn't exist in silicon, thankfully */ @@ -2221,6 +2224,18 @@ static unsigned int arm_cmn_dtc_domain(struct arm_cmn *cmn, void __iomem *xp_reg return FIELD_GET(CMN_DTM_UNIT_INFO_DTC_DOMAIN, readl_relaxed(xp_region + offset)); } +static unsigned int arm_cmn_graviton5_dtc_domain(u16 xp_id) +{ + unsigned int x = (xp_id >> 7) & 0xf; + unsigned int y = (xp_id >> 3) & 0xf; + + /* + * The unit info register reads as zero; derive the DTC domain from + * the XP's mesh coordinates over the 10x14 mesh. + */ + return (x / 5) + (y / 7) * 2; +} + static void arm_cmn_init_node_info(struct arm_cmn *cmn, u32 offset, struct arm_cmn_node *node) { int level; @@ -2266,6 +2281,7 @@ static int arm_cmn_discover(struct arm_cmn *cmn, unsigned int rgn_offset) u64 reg; int i, j; size_t sz; + bool graviton5_workaround = false; arm_cmn_init_node_info(cmn, rgn_offset, &cfg); if (cfg.type != CMN_TYPE_CFG) @@ -2276,6 +2292,13 @@ static int arm_cmn_discover(struct arm_cmn *cmn, unsigned int rgn_offset) reg = readq_relaxed(cfg_region + CMN_CFGM_PERIPH_ID_01); part = FIELD_GET(CMN_CFGM_PID0_PART_0, reg); part |= FIELD_GET(CMN_CFGM_PID1_PART_1, reg) << 8; + + /* Graviton5 has a customised CMN-S3 which needs some fixups */ + if (cmn->part == PART_GRAVITON5) { + cmn->part = PART_CMN_S3; + graviton5_workaround = true; + } + /* 600AE is close enough that it's not really worth more complexity */ if (part == PART_CMN600AE) part = PART_CMN600; @@ -2365,6 +2388,8 @@ static int arm_cmn_discover(struct arm_cmn *cmn, unsigned int rgn_offset) if (cmn->part == PART_CMN600) xp->dtc = -1; + else if (graviton5_workaround) + xp->dtc = arm_cmn_graviton5_dtc_domain(xp->id); else xp->dtc = arm_cmn_dtc_domain(cmn, xp_region); @@ -2443,6 +2468,10 @@ static int arm_cmn_discover(struct arm_cmn *cmn, unsigned int rgn_offset) switch (dn->type) { case CMN_TYPE_DTC: + if (graviton5_workaround) { + /* Node info logical ID is zeroed; use the domain ID */ + dn->logid = xp->dtc; + } cmn->num_dtcs++; dn++; break; @@ -2658,6 +2687,7 @@ static const struct acpi_device_id arm_cmn_acpi_match[] = { { "ARMHC650" }, { "ARMHC700" }, { "ARMHC003" }, + { "AMZN0070", PART_GRAVITON5 }, {} }; MODULE_DEVICE_TABLE(acpi, arm_cmn_acpi_match); -- 2.47.3