From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 9A9CD1FC8; Thu, 5 Jun 2025 06:09:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=13.77.154.182 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749103776; cv=none; b=gaGytrRfiqZM500YoyRMh/2alehV485YoPWLPXHhk7UEbtAuRbhnl33/Us6mP0b6OITCIs6/LSo1QE2vMruUOmtlsqCvzqswF9Zztyf2KEsHkswhaXJnxOeL0w16h48ZaJNAXv7Rb6wVnhTvuwieR2TnQnkc6zKmIW5tCtHQE6E= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749103776; c=relaxed/simple; bh=O84wJObH89CUpgkwkPADWcvnXK7hHeg8rak4mox67q4=; h=Message-ID:Date:MIME-Version:To:Cc:From:Subject:Content-Type; b=P2IYWTVeDs66PoamFX08Ue/TXB9PpkZHHqQ+PNJFhHR9y2mnx/McUuF29TBZ8t7NrpNF9nkNfVURB7MREYxp7cDNeTeaP4YEwURGD84mudst1ZVmXCKWucEOTdF9mhS6obvS8cRzX12cK97JBkmWD+NHOALaLZ/6t7JrDjYGrqI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com; spf=pass smtp.mailfrom=linux.microsoft.com; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b=UPIYNxzi; arc=none smtp.client-ip=13.77.154.182 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b="UPIYNxzi" Received: from [100.64.1.134] (unknown [40.65.108.177]) by linux.microsoft.com (Postfix) with ESMTPSA id A9BD0201FF4E; Wed, 4 Jun 2025 23:09:32 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com A9BD0201FF4E DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1749103773; bh=arEF/2LdOdCfNP5R12P7zhBgPfTao/upFbApLg+9CFw=; h=Date:To:Cc:From:Subject:From; b=UPIYNxzitA7Tyg6oV7jSLomnxLkewK0LYNmWB5L1vLFiQns5uL7IDDNPKkpQ2Ncej /1CMyeG6bIQ/cDEG+9HY9EAwmTKPPrGYt65FKwtvB2D3kwS6Euxy/usrJjKDqXOb97 1oEbEg3gcRr7DpfDv5mJN6+Idr/lN7MeB3Vene2I= Message-ID: <6a92ca86-ad6b-4d49-af6e-1ed7651b8ab8@linux.microsoft.com> Date: Wed, 4 Jun 2025 23:09:31 -0700 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Content-Language: en-US To: kys@microsoft.com, haiyangz@microsoft.com, wei.liu@kernel.org, decui@microsoft.com, ssengar@microsoft.com Cc: romank@linux.microsoft.com, linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org, stable@kernel.org, apais@microsoft.com From: Hardik Garg Subject: [PATCH v3] vmbus: retrieve connection-id from DeviceTree Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit The connection-id determines which hypervisor communication channel the guest should use to talk to the VMBus host. This patch adds support to read this value from the DeviceTree where it exists as a property under the vmbus node with the compatible ID "microsoft,message-connection-id". The property name follows the format , where "vendor": "microsoft" and "field": "message-connection-id" Reading from DeviceTree allows platforms to specify their preferred communication channel, making it more flexible. If the property is not found in the DeviceTree, use the default connection ID (VMBUS_MESSAGE_CONNECTION_ID or VMBUS_MESSAGE_CONNECTION_ID_4 based on protocol version). Signed-off-by: Hardik Garg --- v3: - Added documentation for the new property in DeviceTree bindings v2: https://lore.kernel.org/all/096edaf7-cc90-42b6-aff4-c5f088574e1e@linux.microsoft.com/ v1: https://lore.kernel.org/all/6acee4bf-cb04-43b9-9476-e8d811d26dfd@linux.microsoft.com/ ---  .../devicetree/bindings/bus/microsoft,vmbus.yaml    |  8 ++++++++  drivers/hv/connection.c                             |  6 ++++--  drivers/hv/vmbus_drv.c                              | 13 +++++++++++++  3 files changed, 25 insertions(+), 2 deletions(-) diff --git a/Documentation/devicetree/bindings/bus/microsoft,vmbus.yaml b/Documentation/devicetree/bindings/bus/microsoft,vmbus.yaml index 0bea4f5287ce..729ca6defec6 100644 --- a/Documentation/devicetree/bindings/bus/microsoft,vmbus.yaml +++ b/Documentation/devicetree/bindings/bus/microsoft,vmbus.yaml @@ -17,6 +17,14 @@ properties:    compatible:      const: microsoft,vmbus +  microsoft,message-connection-id: +    description: +      VMBus message connection ID to be used for communication between host and +      guest. If not specified, defaults to VMBUS_MESSAGE_CONNECTION_ID_4 for +      protocol version VERSION_WIN10_V5 and above, or VMBUS_MESSAGE_CONNECTION_ID +      for older versions. +    $ref: /schemas/types.yaml#/definitions/uint32 +    ranges: true    '#address-cells': diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c index be490c598785..e0f38d799d06 100644 --- a/drivers/hv/connection.c +++ b/drivers/hv/connection.c @@ -99,12 +99,14 @@ int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo, u32 version)      if (version >= VERSION_WIN10_V5) {          msg->msg_sint = VMBUS_MESSAGE_SINT;          msg->msg_vtl = ms_hyperv.vtl; -        vmbus_connection.msg_conn_id = VMBUS_MESSAGE_CONNECTION_ID_4;      } else {          msg->interrupt_page = virt_to_phys(vmbus_connection.int_page); -        vmbus_connection.msg_conn_id = VMBUS_MESSAGE_CONNECTION_ID;      } +    /* Set default connection ID if not provided via DeviceTree */ +    if (!vmbus_connection.msg_conn_id) +        vmbus_connection.msg_conn_id = (version >= VERSION_WIN10_V5) ? +            VMBUS_MESSAGE_CONNECTION_ID_4 : VMBUS_MESSAGE_CONNECTION_ID;      /*       * shared_gpa_boundary is zero in non-SNP VMs, so it's safe to always       * bitwise OR it diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c index c236081d0a87..d14d286671cc 100644 --- a/drivers/hv/vmbus_drv.c +++ b/drivers/hv/vmbus_drv.c @@ -2541,10 +2541,23 @@ static int vmbus_device_add(struct platform_device *pdev)      struct of_range range;      struct of_range_parser parser;      struct device_node *np = pdev->dev.of_node; +    unsigned int conn_id;      int ret;      vmbus_root_device = &pdev->dev; +    /* +     * Read connection ID from DeviceTree. The property name follows the +     * format , where: +     * - vendor: "microsoft" +     * - field: "message-connection-id" +     */ +    ret = of_property_read_u32(np, "microsoft,message-connection-id", &conn_id); +    if (!ret) { +        pr_info("VMBus message connection ID: %u\n", conn_id); +        vmbus_connection.msg_conn_id = conn_id; +    } +      ret = of_range_parser_init(&parser, np);      if (ret)          return ret; -- 2.40.4