From patchwork Thu Dec 19 19:16:10 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: admiyo@os.amperecomputing.com X-Patchwork-Id: 13915538 X-Patchwork-Delegate: kuba@kernel.org Received: from SJ2PR03CU002.outbound.protection.outlook.com (mail-westusazon11023112.outbound.protection.outlook.com [52.101.44.112]) (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 DA2D41AA1FF; Thu, 19 Dec 2024 19:16:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=52.101.44.112 ARC-Seal: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734635783; cv=fail; b=JUyw8bkCkzOD1/W57N2WCGUHcpU2mNyvH+uZCXfZyrFkEW57bR3aZ8nQr6tITYmo54wMd0A+QThjFyCLPYseXQGogueBJ+0Jx7LO1wDV4X+oViWwwdKTUmkeqk4Rw8n+2sZ2JC80CT6OMXoxjqmeZd9sVmse+FzxDkP3YzVmTnM= ARC-Message-Signature: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734635783; c=relaxed/simple; bh=trxVEpBV6S5j8anal6eIYnj7avXdmNumbM0psivwygo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: Content-Type:MIME-Version; b=PfDMMP8nDqVX3nUX2HNw29dTMVtCutBuq9s0Abc6ADVIfOhvgsgnhF7IuoPG0wrhfSJJbzx3zHDeDdpdDe200m56u1GJeEGj8ZikJZcPfGzvPxVzpFp55CYPHHfkrByJcVKMC1vCFt1qudU5ixtoscimiv5dCUp52J/PmLje18w= ARC-Authentication-Results: i=2; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=os.amperecomputing.com; spf=pass smtp.mailfrom=os.amperecomputing.com; dkim=pass (1024-bit key) header.d=os.amperecomputing.com header.i=@os.amperecomputing.com header.b=qSzBRiW3; arc=fail smtp.client-ip=52.101.44.112 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=os.amperecomputing.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=os.amperecomputing.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=os.amperecomputing.com header.i=@os.amperecomputing.com header.b="qSzBRiW3" ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=COy6vjqNB/2bavg5ohzJKWuS4cIdyMRNVVxW4EQVDrO9fxr+vUHGlwcfmd+rVzeRGrT0Mda3THl5HlcAOrk9ScIECrH9Wj0HRy8JiDjtJotOtRgyU4Yt7EhNje1OJMJxGwHpXySpDIqItz3XbkxEclJXZoBUHZO0qq/jmQ51a1CXatkN2lNqHUV71k5sma9gOwDb7GJM6mLaMTGaHucwtplQc62D2Eg2RbN3hqeUG+j3kT1lbsh89lMtFkPCOvN0/3ikMKa9B0IfbukUHhJWHFrkfIKjizPfYud6l+7SWGjouNrkAU5u5HVeNQvtLuPZa1xv1P2dolDrhH+ZpWoYRg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector10001; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=cOUJy3eRq3cy5jBeq2SnTH3R/fbWLGKsddOvyKtgvEk=; b=N5wT0+R+zve83lvs6P3lf9ybaz0R1gPIVwp1Yd4yelAkI5wwPS26jA6HHMwhxMkUvFxf9co0hfAGg0945tZYRQQygzK9ulg77OIp/05h0h6XbscG+TNaCwfJPFoPsCjneuLLjVVSwtE+3HFWRRi5wbLKU6pSzlUGhecRs2AwMZFnRKcMRdRpFr8+gFqdSSCpRRdoMvF+6NN1ACt/8zBDV1nsGO93sbFJPbSu5Fds9umbN5R1+tyzX5yeoBa7/iKe5dBE5dOmz7zFvm7Vv/E7i1ewKnlxrDITkyLLOExd/rMMM2+LN4DeOLhlaKOvJBVv//f9i+/Bovk07eRDkKTrVA== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=os.amperecomputing.com; dmarc=pass action=none header.from=os.amperecomputing.com; dkim=pass header.d=os.amperecomputing.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=os.amperecomputing.com; s=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=cOUJy3eRq3cy5jBeq2SnTH3R/fbWLGKsddOvyKtgvEk=; b=qSzBRiW3IId61/d5oULgl1CY8tjtI9/yV4s/FgaMR+hrjzmiE6aJIWGdDyzYnMK9oL8G0jmT6Ygdb1WnIM5nprrtyRgaNau4B/NNB30YEZ1GNscQPShcfTdMtxu8YTEdQO+GRGOjex/xEIjCqIhnx19vAipVngrJ/oNJ1YN5Cl0= Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=os.amperecomputing.com; Received: from SA0PR01MB6171.prod.exchangelabs.com (2603:10b6:806:e5::16) by SJ0PR01MB7527.prod.exchangelabs.com (2603:10b6:a03:3da::12) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.8272.13; Thu, 19 Dec 2024 19:16:17 +0000 Received: from SA0PR01MB6171.prod.exchangelabs.com ([fe80::b0e5:c494:81a3:5e1d]) by SA0PR01MB6171.prod.exchangelabs.com ([fe80::b0e5:c494:81a3:5e1d%6]) with mapi id 15.20.8293.000; Thu, 19 Dec 2024 19:16:17 +0000 From: admiyo@os.amperecomputing.com To: Jeremy Kerr , Matt Johnston , Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Sudeep Holla , Jonathan Cameron , Huisong Li Subject: [PATCH v10 1/1] mctp pcc: Implement MCTP over PCC Transport Date: Thu, 19 Dec 2024 14:16:10 -0500 Message-ID: <20241219191610.257649-2-admiyo@os.amperecomputing.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20241219191610.257649-1-admiyo@os.amperecomputing.com> References: <20241219191610.257649-1-admiyo@os.amperecomputing.com> X-ClientProxiedBy: BL1PR13CA0008.namprd13.prod.outlook.com (2603:10b6:208:256::13) To SA0PR01MB6171.prod.exchangelabs.com (2603:10b6:806:e5::16) Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: SA0PR01MB6171:EE_|SJ0PR01MB7527:EE_ X-MS-Office365-Filtering-Correlation-Id: 62059a8e-50dd-4b8c-bda7-08dd20619cd8 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|366016|7416014|376014|52116014|1800799024|10070799003; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:SA0PR01MB6171.prod.exchangelabs.com;PTR:;CAT:NONE;SFS:(13230040)(366016)(7416014)(376014)(52116014)(1800799024)(10070799003);DIR:OUT;SFP:1102; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: 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 X-OriginatorOrg: os.amperecomputing.com X-MS-Exchange-CrossTenant-Network-Message-Id: 62059a8e-50dd-4b8c-bda7-08dd20619cd8 X-MS-Exchange-CrossTenant-AuthSource: SA0PR01MB6171.prod.exchangelabs.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 19 Dec 2024 19:16:17.3139 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 3bc2b170-fd94-476d-b0ce-4229bdc904a7 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: SJe5WcvQl0M2EX8gebVjtGgexxQOV2tCZnUHCh6usivdEyzsnmtWo8WNc2Vd+p7ul+k2sQRXSQe7YXKc0yBk1+hkoLPw9xjA+NDaANLNbWCVV82OptUTL5E3giHULBvs X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ0PR01MB7527 X-Patchwork-Delegate: kuba@kernel.org From: Adam Young Implementation of network driver for Management Control Transport Protocol(MCTP) over Platform Communication Channel(PCC) DMTF DSP:0292 https://www.dmtf.org/sites/default/files/standards/documents/DSP0292_1.0.0WIP50.pdf MCTP devices are specified by entries in DSDT/SDST and reference channels specified in the PCCT. Communication with other devices use the PCC based doorbell mechanism. Signed-off-by: Adam Young --- drivers/net/mctp/Kconfig | 13 ++ drivers/net/mctp/Makefile | 1 + drivers/net/mctp/mctp-pcc.c | 307 ++++++++++++++++++++++++++++++++++++ 3 files changed, 321 insertions(+) create mode 100644 drivers/net/mctp/mctp-pcc.c diff --git a/drivers/net/mctp/Kconfig b/drivers/net/mctp/Kconfig index 15860d6ac39f..073eb2a21841 100644 --- a/drivers/net/mctp/Kconfig +++ b/drivers/net/mctp/Kconfig @@ -47,6 +47,19 @@ config MCTP_TRANSPORT_I3C A MCTP protocol network device is created for each I3C bus having a "mctp-controller" devicetree property. +config MCTP_TRANSPORT_PCC + tristate "MCTP PCC transport" + depends on ACPI + help + Provides a driver to access MCTP devices over PCC transport, + A MCTP protocol network device is created via ACPI for each + entry in the DST/SDST that matches the identifier. The Platform + communication channels are selected from the corresponding + entries in the PCCT. + + Say y here if you need to connect to MCTP endpoints over PCC. To + compile as a module, use m; the module will be called mctp-pcc. + endmenu endif diff --git a/drivers/net/mctp/Makefile b/drivers/net/mctp/Makefile index e1cb99ced54a..492a9e47638f 100644 --- a/drivers/net/mctp/Makefile +++ b/drivers/net/mctp/Makefile @@ -1,3 +1,4 @@ +obj-$(CONFIG_MCTP_TRANSPORT_PCC) += mctp-pcc.o obj-$(CONFIG_MCTP_SERIAL) += mctp-serial.o obj-$(CONFIG_MCTP_TRANSPORT_I2C) += mctp-i2c.o obj-$(CONFIG_MCTP_TRANSPORT_I3C) += mctp-i3c.o diff --git a/drivers/net/mctp/mctp-pcc.c b/drivers/net/mctp/mctp-pcc.c new file mode 100644 index 000000000000..b114db230a26 --- /dev/null +++ b/drivers/net/mctp/mctp-pcc.c @@ -0,0 +1,307 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * mctp-pcc.c - Driver for MCTP over PCC. + * Copyright (c) 2024, Ampere Computing LLC + */ + +/* Implementation of MCTP over PCC DMTF Specification DSP0256 + * https://www.dmtf.org/sites/default/files/standards/documents/DSP0256_2.0.0WIP50.pdf + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include +#include +#include +#include + +#define MCTP_PAYLOAD_LENGTH 256 +#define MCTP_CMD_LENGTH 4 +#define MCTP_PCC_VERSION 0x1 /* DSP0253 defines a single version: 1 */ +#define MCTP_SIGNATURE "MCTP" +#define MCTP_SIGNATURE_LENGTH (sizeof(MCTP_SIGNATURE) - 1) +#define MCTP_HEADER_LENGTH 12 +#define MCTP_MIN_MTU 68 +#define PCC_MAGIC 0x50434300 +#define PCC_HEADER_FLAG_REQ_INT 0x1 +#define PCC_HEADER_FLAGS PCC_HEADER_FLAG_REQ_INT +#define PCC_DWORD_TYPE 0x0c + +struct mctp_pcc_hdr { + __be32 signature; + __be32 flags; + __be32 length; + char mctp_signature[MCTP_SIGNATURE_LENGTH]; +}; + +struct mctp_pcc_mailbox { + u32 index; + struct pcc_mbox_chan *chan; + struct mbox_client client; +}; + +/* The netdev structure. One of these per PCC adapter. */ +struct mctp_pcc_ndev { + /* spinlock to serialize access to PCC outbox buffer and registers + * Note that what PCC calls registers are memory locations, not CPU + * Registers. They include the fields used to synchronize access + * between the OS and remote endpoints. + * + * Only the Outbox needs a spinlock, to prevent multiple + * sent packets triggering multiple attempts to over write + * the outbox. The Inbox buffer is controlled by the remote + * service and a spinlock would have no effect. + */ + spinlock_t lock; + struct mctp_dev mdev; + struct acpi_device *acpi_device; + struct mctp_pcc_mailbox inbox; + struct mctp_pcc_mailbox outbox; +}; + +static void mctp_pcc_client_rx_callback(struct mbox_client *c, void *buffer) +{ + struct mctp_pcc_ndev *mctp_pcc_ndev; + struct mctp_pcc_hdr mctp_pcc_hdr; + struct mctp_skb_cb *cb; + struct sk_buff *skb; + void *skb_buf; + u32 data_len; + + mctp_pcc_ndev = container_of(c, struct mctp_pcc_ndev, inbox.client); + memcpy_fromio(&mctp_pcc_hdr, mctp_pcc_ndev->inbox.chan->shmem, + sizeof(struct mctp_pcc_hdr)); + data_len = mctp_pcc_hdr.length + MCTP_HEADER_LENGTH; + if (data_len > mctp_pcc_ndev->mdev.dev->mtu) { + dev_dstats_rx_dropped(mctp_pcc_ndev->mdev.dev); + return; + } + + skb = netdev_alloc_skb(mctp_pcc_ndev->mdev.dev, data_len); + if (!skb) { + dev_dstats_rx_dropped(mctp_pcc_ndev->mdev.dev); + return; + } + dev_dstats_rx_add(mctp_pcc_ndev->mdev.dev, data_len); + + skb->protocol = htons(ETH_P_MCTP); + skb_buf = skb_put(skb, data_len); + memcpy_fromio(skb_buf, mctp_pcc_ndev->inbox.chan->shmem, data_len); + + skb_reset_mac_header(skb); + skb_pull(skb, sizeof(struct mctp_pcc_hdr)); + skb_reset_network_header(skb); + cb = __mctp_cb(skb); + cb->halen = 0; + netif_rx(skb); +} + +static netdev_tx_t mctp_pcc_tx(struct sk_buff *skb, struct net_device *ndev) +{ + struct mctp_pcc_ndev *mpnd = netdev_priv(ndev); + struct mctp_pcc_hdr *mctp_pcc_header; + void __iomem *buffer; + unsigned long flags; + int len = skb->len; + + dev_dstats_tx_add(ndev, len); + + spin_lock_irqsave(&mpnd->lock, flags); + mctp_pcc_header = skb_push(skb, sizeof(struct mctp_pcc_hdr)); + buffer = mpnd->outbox.chan->shmem; + mctp_pcc_header->signature = PCC_MAGIC | mpnd->outbox.index; + mctp_pcc_header->flags = PCC_HEADER_FLAGS; + memcpy(mctp_pcc_header->mctp_signature, MCTP_SIGNATURE, + MCTP_SIGNATURE_LENGTH); + mctp_pcc_header->length = len + MCTP_SIGNATURE_LENGTH; + + memcpy_toio(buffer, skb->data, skb->len); + mpnd->outbox.chan->mchan->mbox->ops->send_data(mpnd->outbox.chan->mchan, + NULL); + spin_unlock_irqrestore(&mpnd->lock, flags); + + dev_consume_skb_any(skb); + return NETDEV_TX_OK; +} + +static const struct net_device_ops mctp_pcc_netdev_ops = { + .ndo_start_xmit = mctp_pcc_tx, +}; + +static void mctp_pcc_setup(struct net_device *ndev) +{ + ndev->type = ARPHRD_MCTP; + ndev->hard_header_len = 0; + ndev->tx_queue_len = 0; + ndev->flags = IFF_NOARP; + ndev->netdev_ops = &mctp_pcc_netdev_ops; + ndev->needs_free_netdev = true; + ndev->pcpu_stat_type = NETDEV_PCPU_STAT_DSTATS; +} + +struct mctp_pcc_lookup_context { + int index; + u32 inbox_index; + u32 outbox_index; +}; + +static acpi_status lookup_pcct_indices(struct acpi_resource *ares, + void *context) +{ + struct mctp_pcc_lookup_context *luc = context; + struct acpi_resource_address32 *addr; + + switch (ares->type) { + case PCC_DWORD_TYPE: + break; + default: + return AE_OK; + } + + addr = ACPI_CAST_PTR(struct acpi_resource_address32, &ares->data); + switch (luc->index) { + case 0: + luc->outbox_index = addr[0].address.minimum; + break; + case 1: + luc->inbox_index = addr[0].address.minimum; + break; + } + luc->index++; + return AE_OK; +} + +static void mctp_cleanup_netdev(void *data) +{ + struct net_device *ndev = data; + + mctp_unregister_netdev(ndev); +} + +static void mctp_cleanup_channel(void *data) +{ + struct pcc_mbox_chan *chan = data; + + pcc_mbox_free_channel(chan); +} + +static int mctp_pcc_initialize_mailbox(struct device *dev, + struct mctp_pcc_mailbox *box, u32 index) +{ + int ret; + + box->index = index; + box->chan = pcc_mbox_request_channel(&box->client, index); + if (IS_ERR(box->chan)) + return PTR_ERR(box->chan); + devm_add_action_or_reset(dev, mctp_cleanup_channel, box->chan); + ret = pcc_mbox_ioremap(box->chan->mchan); + if (ret) + return -EINVAL; + return 0; +} + +static int mctp_pcc_driver_add(struct acpi_device *acpi_dev) +{ + struct mctp_pcc_lookup_context context = {0, 0, 0}; + struct mctp_pcc_ndev *mctp_pcc_ndev; + struct device *dev = &acpi_dev->dev; + struct net_device *ndev; + acpi_handle dev_handle; + acpi_status status; + int mctp_pcc_mtu; + char name[32]; + int rc; + + dev_dbg(dev, "Adding mctp_pcc device for HID %s\n", + acpi_device_hid(acpi_dev)); + dev_handle = acpi_device_handle(acpi_dev); + status = acpi_walk_resources(dev_handle, "_CRS", lookup_pcct_indices, + &context); + if (!ACPI_SUCCESS(status)) { + dev_err(dev, "FAILURE to lookup PCC indexes from CRS\n"); + return -EINVAL; + } + + //inbox initialization + snprintf(name, sizeof(name), "mctpipcc%d", context.inbox_index); + ndev = alloc_netdev(sizeof(struct mctp_pcc_ndev), name, NET_NAME_ENUM, + mctp_pcc_setup); + if (!ndev) + return -ENOMEM; + + mctp_pcc_ndev = netdev_priv(ndev); + rc = devm_add_action_or_reset(dev, mctp_cleanup_netdev, ndev); + if (rc) + goto cleanup_netdev; + spin_lock_init(&mctp_pcc_ndev->lock); + + rc = mctp_pcc_initialize_mailbox(dev, &mctp_pcc_ndev->inbox, + context.inbox_index); + if (rc) + goto cleanup_netdev; + mctp_pcc_ndev->inbox.client.rx_callback = mctp_pcc_client_rx_callback; + + //outbox initialization + rc = mctp_pcc_initialize_mailbox(dev, &mctp_pcc_ndev->outbox, + context.outbox_index); + if (rc) + goto cleanup_netdev; + + mctp_pcc_ndev->acpi_device = acpi_dev; + mctp_pcc_ndev->inbox.client.dev = dev; + mctp_pcc_ndev->outbox.client.dev = dev; + mctp_pcc_ndev->mdev.dev = ndev; + acpi_dev->driver_data = mctp_pcc_ndev; + + /* There is no clean way to pass the MTU to the callback function + * used for registration, so set the values ahead of time. + */ + mctp_pcc_mtu = mctp_pcc_ndev->outbox.chan->shmem_size - + sizeof(struct mctp_pcc_hdr); + ndev->mtu = MCTP_MIN_MTU; + ndev->max_mtu = mctp_pcc_mtu; + ndev->min_mtu = MCTP_MIN_MTU; + + /* ndev needs to be freed before the iomemory (mapped above) gets + * unmapped, devm resources get freed in reverse to the order they + * are added. + */ + rc = register_netdev(ndev); + return rc; +cleanup_netdev: + free_netdev(ndev); + return rc; +} + +static const struct acpi_device_id mctp_pcc_device_ids[] = { + { "DMT0001"}, + {} +}; + +static struct acpi_driver mctp_pcc_driver = { + .name = "mctp_pcc", + .class = "Unknown", + .ids = mctp_pcc_device_ids, + .ops = { + .add = mctp_pcc_driver_add, + }, +}; + +module_acpi_driver(mctp_pcc_driver); + +MODULE_DEVICE_TABLE(acpi, mctp_pcc_device_ids); + +MODULE_DESCRIPTION("MCTP PCC ACPI device"); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Adam Young ");