From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx0a-0031df01.pphosted.com (mx0a-0031df01.pphosted.com [205.220.168.131]) (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 8D66A215773; Fri, 18 Jul 2025 07:12:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=205.220.168.131 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752822747; cv=none; b=gnf/8/Lr04lAMgWWb5gT6wjP5oHHtozko9jhnV+2Az07y71dDUMWKTDiIlX45lsieu+m6cCFUDztOOfoBkbm39BrVQFhpZYcaXps1fUrBKXPH1r9LiilUBS7q6Ao+agi+pkAUOoArH+D6rWDKVgczJzgpoFercnzWmNb1twHl0k= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752822747; c=relaxed/simple; bh=0K4SPuuIcngGAFPRvbGGNcGdo9ZYodG/HB4xyll+vhg=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=oD6jR9v/d/GOV363bxzBSwpvZpTz6aXIQFrquA68CKZQK9Btjz94JOwlZmH6D810heIzVu+mEm+MUcFJ/CfrY3QGBu+IdgyY2i22LMvuKLjzee1/9rdzj3xmiwPJj0yOdDnNssCjbjDZmtRaW3EJZ53mvG8RsvARUSir8Kkh2Us= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=oss.qualcomm.com; spf=pass smtp.mailfrom=qualcomm.com; dkim=pass (2048-bit key) header.d=qualcomm.com header.i=@qualcomm.com header.b=LH/dj1xr; arc=none smtp.client-ip=205.220.168.131 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=oss.qualcomm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=qualcomm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=qualcomm.com header.i=@qualcomm.com header.b="LH/dj1xr" Received: from pps.filterd (m0279863.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 56I669X2022240; Fri, 18 Jul 2025 07:12:14 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=qualcomm.com; h= cc:content-transfer-encoding:date:from:in-reply-to:message-id :mime-version:references:subject:to; s=qcppdkim1; bh=zVcXn+xouwm 9M08R+gXXqzI0UC+BcJoS5cp4Pak5RCg=; b=LH/dj1xrEt38k7RrIWwclrbklPu Dh+hCfBGof3RDjcEb4O7eBy0c6LtS1kjaranW9rv1+DWs+J/MnczEvtfkyl7Qdx/ nGcsKFkIbvzfNsKXcpZmGsyF54T3nAJoFVw4CM+JnH2Z0m5moYIFSTx4S26YFjN5 j+GShp4kcGIlMOBhrGMqcRE8m9Tk3Zmxp/Xv9lUyijo8/vfqM9XCJ+jTS8wTwYv2 hAqib8hv16zq2bAnYezEmxuX+/bv839BlAZtMJn8v8ANxrC9bBJ7xCS5e3oY282M /gBZBbPdI+OCX6kxybao7K1rb/d2xVi2dAALSVznoxLpSZornzdWzWydyWA== Received: from aptaippmta01.qualcomm.com (tpe-colo-wan-fw-bordernet.qualcomm.com [103.229.16.4]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 47wqsyagj3-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 18 Jul 2025 07:12:14 +0000 (GMT) Received: from pps.filterd (APTAIPPMTA01.qualcomm.com [127.0.0.1]) by APTAIPPMTA01.qualcomm.com (8.18.1.2/8.18.1.2) with ESMTP id 56I7CC3v023132; Fri, 18 Jul 2025 07:12:12 GMT Received: from pps.reinject (localhost [127.0.0.1]) by APTAIPPMTA01.qualcomm.com (PPS) with ESMTPS id 47ugsn0pq5-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 18 Jul 2025 07:12:12 +0000 Received: from APTAIPPMTA01.qualcomm.com (APTAIPPMTA01.qualcomm.com [127.0.0.1]) by pps.reinject (8.17.1.5/8.17.1.5) with ESMTP id 56I7CCVV023123; Fri, 18 Jul 2025 07:12:12 GMT Received: from cse-cd01-lnx.ap.qualcomm.com (cse-cd01-lnx.qualcomm.com [10.64.75.209]) by APTAIPPMTA01.qualcomm.com (PPS) with ESMTPS id 56I7CBb4023115 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 18 Jul 2025 07:12:12 +0000 Received: by cse-cd01-lnx.ap.qualcomm.com (Postfix, from userid 4438065) id 0035020F1D; Fri, 18 Jul 2025 15:12:09 +0800 (CST) From: Ziyue Zhang To: andersson@kernel.org, konradybcio@kernel.org, robh@kernel.org, krzk+dt@kernel.org, conor+dt@kernel.org, jingoohan1@gmail.com, mani@kernel.org, lpieralisi@kernel.org, kwilczynski@kernel.org, bhelgaas@google.com, johan+linaro@kernel.org, vkoul@kernel.org, kishon@kernel.org, neil.armstrong@linaro.org, abel.vesa@linaro.org, kw@linux.com Cc: linux-arm-msm@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, linux-phy@lists.infradead.org, qiang.yu@oss.qualcomm.com, quic_krichai@quicinc.com, quic_vbadigan@quicinc.com, Ziyue Zhang Subject: [PATCH v4 2/4] dt-bindings: PCI: qcom,pcie-sa8775p: document link_down reset Date: Fri, 18 Jul 2025 15:12:05 +0800 Message-Id: <20250718071207.160988-3-ziyue.zhang@oss.qualcomm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20250718071207.160988-1-ziyue.zhang@oss.qualcomm.com> References: <20250718071207.160988-1-ziyue.zhang@oss.qualcomm.com> Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-QCInternal: smtphost X-QCInternal: smtphost X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjUwNzE4MDA1NSBTYWx0ZWRfX9ICvh5VfJcgM 7gJRT/ZaSHPUvNsxiNrGD0Nm8ky6+52l18noIws6SB9aTBYbXDG1C+1ysxEnJKoUqSXq/sE/14g SV3qvzw/eMXd1lTNnzCmmaQnuh7qUn+n44qGWrYxnI8nOv/sa9uVq8jI1MCrBiCWG3odOiRsW99 /lkhdXX8p5i0FDaq0YiUncl1q1KUgQ6i9eux5i1gwKsxWuE8GTDFo44gzlzxJmp+R5hUhrW6xaL KrCFmtvuCV3rza0iZpwdVQmS7TL73csZI6X4i1wHVkHvXaJ+fHmIni91ftNeelA0JTEO+nJz34b BEVSU7eKemhvnnM/d8Ha7hNx4xBp3wM5JB6XkPaHjtgusVRkk67XI1ZNJt+xw5CDEoWPXTexgYc HsUTXsF7gX549v1oFdicllxm2v5CaUKjXqlZVbxWUoAT3ugUEzBdOFJ6ooOePYVchWgwMxto X-Proofpoint-GUID: VVjllUy0HmZqRksZg4edSU1KiWeF0kZC X-Proofpoint-ORIG-GUID: VVjllUy0HmZqRksZg4edSU1KiWeF0kZC X-Authority-Analysis: v=2.4 cv=McZsu4/f c=1 sm=1 tr=0 ts=6879f3ce cx=c_pps a=nuhDOHQX5FNHPW3J6Bj6AA==:117 a=nuhDOHQX5FNHPW3J6Bj6AA==:17 a=Wb1JkmetP80A:10 a=EUspDBNiAAAA:8 a=pGOvZgHL2iAvQvMqjSkA:9 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=2025-07-18_01,2025-07-17_02,2025-03-28_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 mlxlogscore=999 impostorscore=0 mlxscore=0 phishscore=0 adultscore=0 lowpriorityscore=0 bulkscore=0 clxscore=1015 suspectscore=0 spamscore=0 priorityscore=1501 classifier=spam authscore=0 authtc=n/a authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.19.0-2505280000 definitions=main-2507180055 Each PCIe controller on SA8775P includes a 'link_down' reset line in hardware. This patch documents the reset in the device tree binding. The 'link_down' reset is used to forcefully bring down the PCIe link layer, which is useful in scenarios such as link recovery after errors, power management transitions, and hotplug events. Including this reset line improves robustness and provides finer control over PCIe controller behavior. As the 'link_down' reset was omitted in the initial submission, it is now being documented. While this reset is not required for most of the block's basic functionality, and device trees lacking it will continue to function correctly in most cases, it is necessary to ensure maximum robustness when shutting down or recovering the PCIe core. Therefore, its inclusion is justified despite the minor ABI change. Signed-off-by: Ziyue Zhang --- .../devicetree/bindings/pci/qcom,pcie-sa8775p.yaml | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/Documentation/devicetree/bindings/pci/qcom,pcie-sa8775p.yaml b/Documentation/devicetree/bindings/pci/qcom,pcie-sa8775p.yaml index 4b91b5608013..19afe2a03409 100644 --- a/Documentation/devicetree/bindings/pci/qcom,pcie-sa8775p.yaml +++ b/Documentation/devicetree/bindings/pci/qcom,pcie-sa8775p.yaml @@ -66,11 +66,14 @@ properties: - const: global resets: - maxItems: 1 + items: + - description: PCIe controller reset + - description: PCIe link down reset reset-names: items: - const: pci + - const: link_down required: - interconnects @@ -166,8 +169,10 @@ examples: power-domains = <&gcc PCIE_0_GDSC>; - resets = <&gcc GCC_PCIE_0_BCR>; - reset-names = "pci"; + resets = <&gcc GCC_PCIE_0_BCR>, + <&gcc GCC_PCIE_0_LINK_DOWN_BCR>; + reset-names = "pci", + "link_down"; perst-gpios = <&tlmm 2 GPIO_ACTIVE_LOW>; wake-gpios = <&tlmm 0 GPIO_ACTIVE_HIGH>; -- 2.34.1