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 739E024886E for ; Thu, 23 Apr 2026 13:30:16 +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=1776951017; cv=none; b=Eary4dRQij+ENgxBmQGYqENtmctjked/aZjGrT022gnhNlnAHZsoiaqmk522VBq9gtvl54O+KwWIXaKHPpB9L5yk17bSkjlyKk6YhuFL9f//Th9UjVcoV7gruo07HzBQwEtjoTEZo/jXqL/VSLuSc/yDWooF+WkvbP0h9CT0IG0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776951017; c=relaxed/simple; bh=IQk9tf8jtI734WVYY1gXH96FiyZAYSnp0pjs1ZGk6Dw=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=HozXErbOL9OdSj33U5eMbcoOmezx5sC9RLsOOBccUgpsOS39K7uYtJMFXiRn/IoLzRNsseYHDeXdkMKdpUXMa9ShDF/w7948QUwjSxigyOYSENggpb4t8ChLByqTACryhlsltAgnKVhEip9ej4Q9tYMxUD3gTIrvvy0EEdre1sc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=oss.qualcomm.com; spf=pass smtp.mailfrom=oss.qualcomm.com; dkim=pass (2048-bit key) header.d=qualcomm.com header.i=@qualcomm.com header.b=W83kJCb9; dkim=pass (2048-bit key) header.d=oss.qualcomm.com header.i=@oss.qualcomm.com header.b=HnsKjtIQ; 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=oss.qualcomm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=qualcomm.com header.i=@qualcomm.com header.b="W83kJCb9"; dkim=pass (2048-bit key) header.d=oss.qualcomm.com header.i=@oss.qualcomm.com header.b="HnsKjtIQ" Received: from pps.filterd (m0279864.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.18.1.11/8.18.1.11) with ESMTP id 63N8tqZM028797 for ; Thu, 23 Apr 2026 13:30:16 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=qualcomm.com; h= cc:content-transfer-encoding:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to; s=qcppdkim1; bh= oFs1RbQ0XkUdAOvZ3WrAthRL+JhVyLKMhXKejRMG50Q=; b=W83kJCb90RXTWXsv +N4MsWO5j3J1l018/9HTuTnXyck6N5sO3sEEcmhS6D/J1UM/Numbte+0JLmFIG7Y fDB8QyPCUSsSLwS8LDR933AUrLI7bmggaJMItyAr9c89SwvCR68I0DTo74N1nMPR mUyAUDvVEp8wWry2YPw3McZb9pj9zoLi+oijVtIH/sCL4RxmiT9PSj5zHM7B96YU 8Wk+xoeVo6mf5vdmbRsDNU1TM8zC+h2Q0oj+OnIVF4Tb1JyUEKvEI3BRvZWV+Ajz 1atvVcHB4z+RISev0c0n14GFqxUk7VkRYeozQfZ2qqh1VZnXh5sZqMLtyfM5Peup 5+72rQ== Received: from mail-pl1-f200.google.com (mail-pl1-f200.google.com [209.85.214.200]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 4dqdjm1qqe-1 (version=TLSv1.3 cipher=TLS_AES_128_GCM_SHA256 bits=128 verify=NOT) for ; Thu, 23 Apr 2026 13:30:15 +0000 (GMT) Received: by mail-pl1-f200.google.com with SMTP id d9443c01a7336-2b24308165dso77481515ad.1 for ; Thu, 23 Apr 2026 06:30:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oss.qualcomm.com; s=google; t=1776951015; x=1777555815; darn=vger.kernel.org; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:from:to:cc:subject:date:message-id :reply-to; bh=oFs1RbQ0XkUdAOvZ3WrAthRL+JhVyLKMhXKejRMG50Q=; b=HnsKjtIQp1p0pIkHzGrUR8cXxpLeaEE93TYXK+1K0N7hnVuKIu4UBYjtKCONCRilLy pJV0SwGAwRU0kTvEl+Vps3rlVQO27EQ1b7mUzEZygji60mHO8/1crVs2y6DYDEIWJzPt dNEbGLWBgssBbFtVU7RF2hwqNDr89FANxN9Yw1wg2sUbf9EvLZs44FVnktDSmGhw1NNH MNYGeRTLZlA5i22ohQo5Xe/qPVN9YtgInibaiLh3Upsj0oOjTUdfdqgf62hBjyv9K2CI ks3+D5UbGq5v144CZXN4RkzXHCCd3T0YQ4V8nhGanZQ8DGeMN3yTLttZfZcEptqgd5Nm qqOQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1776951015; x=1777555815; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:x-gm-gg:x-gm-message-state:from:to :cc:subject:date:message-id:reply-to; bh=oFs1RbQ0XkUdAOvZ3WrAthRL+JhVyLKMhXKejRMG50Q=; b=VQvV6BZqAx+vomocoY555hfTTeJSDgK+7t9vscPLPoLnoz4bqQOgGyOcVZtyVMvyiq vZZe3dxoopb2iWqAZHHuTsqsoCJU21AmgHN6kyMMh6Cr7p0Qh1Mz/fsZsLQtEdc1LAci WFD+/RE1Dm0WKMYCgmjwsM+LNGGDOXnQSw+SSoesLtMeHp2J8FFNf2HRzj8ufO+c885e IJSuA5jn/XvQpEAzouwiDRN1j3g6r01BlCebdfahQFgS21n8TTcjRN+QkaqI00/7NhoR 0kLG9Tn0Rmay4gFn1TWH5oqrJF5HOmX9vN4AnIoEknNlwokFyzwJpMiDcjIT3PQBoJi6 H9ig== X-Forwarded-Encrypted: i=1; AFNElJ/qom6fleOfNBGiDxKzUyPx+qLQtoYJpB9Z7N9E9kTD1cDH2LsdYNKW7fhkIyF/O2C+Uc1v2LIUMR/hduE=@vger.kernel.org X-Gm-Message-State: AOJu0YwoN4We1xUYaHAeugCc0NPELg3B/es2cZyxFRK9GU4NoG9+9rr8 QyDfXbn8kmNxCfYsUtF5jrx93IGhKw9NR1oFD/PO4hDZw23HsZsjfFaRIgLfkA8GyE6rSCYBsVk 4vXZGyG49/k0oAezerJmR424Plrc3uuZNe2JcNUU8kVZmGYU1TaKNB4Bzh2ajzfTFFrE= X-Gm-Gg: AeBDiethhpAGpDb51mP+HgD1G/JisnNFpHelL62UVT5abN9bou6aAS8PEDCDB4qJ/Kt GL2QfUxBt1O8u6FkK4LWiE9O1ZgR7vqx/hICSOhMSJfjWPBKzHzYrZCzZ9Ugt7lmbIYzCKOmOBz XPDHyF9KzJczLEdGy9FcGfU98PC5FLlHT5aKNZg4vyBVtTJFdfwcm6a6ZgfFoCoseLU5b8sipMO BQaMjZJHpH+uoxFAIgPj49XIEsBiW+6vnA+HmsK3BpnTqaXzSNk2hJ/N+mk6vSkFbTdUFvzKnQU 1ieREcO+56PLNTszIMNQ02IgUWPBTg6PrCL2TMg1OudAuWmsZ6wvfkRbsN+3CA5UVWFwWhllpI5 zsnsveVyfIDww0kO5AESFeq//Cwzlp20ATcuurBkPZ84vP8KzeyXyePPd3S1Ea68gkA== X-Received: by 2002:a17:903:1104:b0:2b4:6529:7b9f with SMTP id d9443c01a7336-2b5f9f37032mr302687055ad.26.1776951014865; Thu, 23 Apr 2026 06:30:14 -0700 (PDT) X-Received: by 2002:a17:903:1104:b0:2b4:6529:7b9f with SMTP id d9443c01a7336-2b5f9f37032mr302686055ad.26.1776951014097; Thu, 23 Apr 2026 06:30:14 -0700 (PDT) Received: from hu-bvisredd-hyd.qualcomm.com ([202.46.22.19]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-2b5fab0cbaasm198795635ad.54.2026.04.23.06.30.05 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 23 Apr 2026 06:30:13 -0700 (PDT) From: Vishnu Reddy Date: Thu, 23 Apr 2026 18:59:31 +0530 Subject: [PATCH v2 02/13] drivers: base: Add generic dma context bus Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260423-glymur-v2-2-0296bccb9f4e@oss.qualcomm.com> References: <20260423-glymur-v2-0-0296bccb9f4e@oss.qualcomm.com> In-Reply-To: <20260423-glymur-v2-0-0296bccb9f4e@oss.qualcomm.com> To: Bryan O'Donoghue , Vikash Garodia , Dikshita Agarwal , Abhinav Kumar , Mauro Carvalho Chehab , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Joerg Roedel , Will Deacon , Robin Murphy , Bjorn Andersson , Konrad Dybcio , Stefan Schmidt , Hans Verkuil , Greg Kroah-Hartman , "Rafael J. Wysocki" , Danilo Krummrich , Thierry Reding , Mikko Perttunen , David Airlie , Simona Vetter , Jonathan Hunter Cc: linux-media@vger.kernel.org, linux-arm-msm@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, iommu@lists.linux.dev, driver-core@lists.linux.dev, dri-devel@lists.freedesktop.org, linux-tegra@vger.kernel.org, Vishnu Reddy , Ekansh Gupta , Dmitry Baryshkov X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=ed25519-sha256; t=1776950985; l=5182; i=busanna.reddy@oss.qualcomm.com; s=20260216; h=from:subject:message-id; bh=m9Ev3cg1dRS/apkqmuIWrlLItkWfgL3nCRaQ+GTJ4d8=; b=a0MO/i8o4a8De0o+pVmxc5nct6busfcAWycf0+sRmWbw7J9/KUDBhEJPpZ7lySVphzTFDiOk0 lCbAAc8uQyBCNukA9WgkyrwbsxQ7npM3UxMTlbG7g7ze+2dYMgz8VVH X-Developer-Key: i=busanna.reddy@oss.qualcomm.com; a=ed25519; pk=9vmy9HahBKVAa+GBFj1yHVbz0ey/ucIs1hrlfx+qtok= X-Authority-Analysis: v=2.4 cv=EZn4hvmC c=1 sm=1 tr=0 ts=69ea1ee7 cx=c_pps a=IZJwPbhc+fLeJZngyXXI0A==:117 a=fChuTYTh2wq5r3m49p7fHw==:17 a=IkcTkHD0fZMA:10 a=A5OVakUREuEA:10 a=s4-Qcg_JpJYA:10 a=VkNPw1HP01LnGYTKEx00:22 a=u7WPNUs3qKkmUXheDGA7:22 a=DJpcGTmdVt4CTyJn9g5Z:22 a=EUspDBNiAAAA:8 a=nxtABoNUPiTGfhWLCFsA:9 a=QEXdDO2ut3YA:10 a=uG9DUKGECoFWVXl0Dc02:22 X-Proofpoint-GUID: GpXfVcoVg86JEfySEEBvzaNQxkdESJnF X-Proofpoint-ORIG-GUID: GpXfVcoVg86JEfySEEBvzaNQxkdESJnF X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwNDIzMDEzNCBTYWx0ZWRfX5CNC+JJCBFFL Zz8UG7uOGTlS9wQXiN1VRpy1sOm0UMKeWJ+tBl9kLmZIdJ8IDTyUbi80qeJxKf7fHPbhzj2VkJv FuV0NtW7zrzYwwXXHK4vU9iwusMkWYbH4rFxecz1AIftguN0SeFjUrHIXANslr2rCh6ScRo1/AM iKT/SEBGqjhE02Xm3hV758InyTzIVetGNVO0Lifa8x4hzqsHx26lKRCZdO9x/4Wk8bIXh1L1vGE zHzTMoe0gsOxDSrKoGc4Kznew+EsjeIEbF4u+thMeraejh2D3Y7Xl3rRB+Hb6yEMnMuSf1ufPUL gWoEslt6SyHAXPO6EKC2vdwkCQ+RIp7vZH5EWBW/o3J1dXox1gnbvPQ4391MTqO2ORZGAbHpgmf n4+X8WkD8e4maP2OeWpXjP5hKSYgpKhMpkWpoQMzEdl6hZMlNQB778aXEhf00YpJpjS2L02YV0j s3iqTljiBd+DiGmO0uw== X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1143,Hydra:6.1.51,FMLib:17.12.100.49 definitions=2026-04-23_03,2026-04-21_02,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 suspectscore=0 priorityscore=1501 phishscore=0 lowpriorityscore=0 bulkscore=0 spamscore=0 clxscore=1015 impostorscore=0 malwarescore=0 adultscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2604200000 definitions=main-2604230134 From: Ekansh Gupta When a driver needs to create virtual device at runtime and map it to an IOMMU context for memory isolation, there is no common bus available for this purpose. Each driver ends up implementing its own bus type, leading to duplicated logic across multiple drivers. host1x driver implemented its own bus type to attach an IOMMU context to a dynamically created device. The Iris VPU driver now has the same requirement. Rather than duplicating the same bus logic again, a shared bus type is introduced under drivers/base that multiple drivers can use directly. The bus takes care of creating a device and attaching the IOMMU context to it based on the client inputs. Suggested-by: Dmitry Baryshkov Signed-off-by: Ekansh Gupta Signed-off-by: Vikash Garodia Signed-off-by: Vishnu Reddy --- drivers/base/Kconfig | 3 ++ drivers/base/Makefile | 1 + drivers/base/dma_context_bus.c | 77 +++++++++++++++++++++++++++++++++++++++++ include/linux/dma_context_bus.h | 26 ++++++++++++++ 4 files changed, 107 insertions(+) diff --git a/drivers/base/Kconfig b/drivers/base/Kconfig index f7d385cbd3ba..499ea92dd88f 100644 --- a/drivers/base/Kconfig +++ b/drivers/base/Kconfig @@ -4,6 +4,9 @@ menu "Generic Driver Options" config AUXILIARY_BUS bool +config DMA_CONTEXT_BUS + bool + config UEVENT_HELPER bool "Support for uevent helper" help diff --git a/drivers/base/Makefile b/drivers/base/Makefile index 8074a10183dc..348e69695e55 100644 --- a/drivers/base/Makefile +++ b/drivers/base/Makefile @@ -8,6 +8,7 @@ obj-y := component.o core.o bus.o dd.o syscore.o \ topology.o container.o property.o cacheinfo.o \ swnode.o faux.o obj-$(CONFIG_AUXILIARY_BUS) += auxiliary.o +obj-$(CONFIG_DMA_CONTEXT_BUS) += dma_context_bus.o obj-$(CONFIG_DEVTMPFS) += devtmpfs.o obj-y += power/ obj-$(CONFIG_ISA_BUS_API) += isa.o diff --git a/drivers/base/dma_context_bus.c b/drivers/base/dma_context_bus.c new file mode 100644 index 000000000000..c2ac189ce08d --- /dev/null +++ b/drivers/base/dma_context_bus.c @@ -0,0 +1,77 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries. + */ + +#include +#include + +static atomic_t dma_context_bus_device_id = ATOMIC_INIT(0); + +static int dma_context_bus_device_configure(struct device *dev) +{ + const u32 *iommu_fid = dev_get_drvdata(dev); + struct device_node *of_node = dev->of_node; + + if (!of_node) + of_node = dev->parent->of_node; + + return of_dma_configure_id(dev, of_node, true, iommu_fid); +} + +const struct bus_type dma_context_bus_type = { + .name = "dma-context-bus", + .dma_configure = dma_context_bus_device_configure, +}; +EXPORT_SYMBOL_GPL(dma_context_bus_type); + +static void release_dma_context_bus_device(struct device *dev) +{ + kfree(dev); +} + +struct device *create_dma_context_bus_device(struct device *parent_device, + struct device_node *of_node, + u64 dma_mask, const u32 *iommu_fid) +{ + struct device *dev; + int dev_id, ret; + + dev = kzalloc_obj(*dev); + if (!dev) + return ERR_PTR(-ENOMEM); + + dev->release = release_dma_context_bus_device; + dev->bus = &dma_context_bus_type; + dev->parent = parent_device; + dev->coherent_dma_mask = dma_mask; + dev->dma_mask = &dev->coherent_dma_mask; + dev->of_node = of_node; + + dev_id = atomic_inc_return(&dma_context_bus_device_id); + dev_set_name(dev, "dma-context-bus-%d", dev_id); + dev_set_drvdata(dev, (void *)iommu_fid); + + ret = device_register(dev); + if (ret) { + put_device(dev); + return ERR_PTR(ret); + } + + return dev; +} +EXPORT_SYMBOL_GPL(create_dma_context_bus_device); + +static int __init dma_context_bus_init(void) +{ + int err; + + err = bus_register(&dma_context_bus_type); + if (err) { + pr_err("dma-context-bus registration failed: %d\n", err); + return err; + } + + return 0; +} +postcore_initcall(dma_context_bus_init); diff --git a/include/linux/dma_context_bus.h b/include/linux/dma_context_bus.h new file mode 100644 index 000000000000..3d89594fbce4 --- /dev/null +++ b/include/linux/dma_context_bus.h @@ -0,0 +1,26 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries. + */ + +#ifndef _LINUX_DMA_CONTEXT_BUS_H +#define _LINUX_DMA_CONTEXT_BUS_H + +#include + +#ifdef CONFIG_DMA_CONTEXT_BUS +extern const struct bus_type dma_context_bus_type; + +struct device *create_dma_context_bus_device(struct device *parent_device, + struct device_node *of_node, + u64 dma_mask, const u32 *iommu_f_id); +#else +static inline struct device *create_dma_context_bus_device(struct device *parent_device, + struct device_node *of_node, + u64 dma_mask, const u32 *iommu_f_id) +{ + return NULL; +} +#endif + +#endif /* _LINUX_DMA_CONTEXT_BUS_H */ -- 2.34.1