From patchwork Tue May 5 16:58:20 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eddie James X-Patchwork-Id: 201062 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3F7C1C47247 for ; Tue, 5 May 2020 16:59:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 248462083B for ; Tue, 5 May 2020 16:59:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730715AbgEEQ66 (ORCPT ); Tue, 5 May 2020 12:58:58 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:26116 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1730569AbgEEQ6j (ORCPT ); Tue, 5 May 2020 12:58:39 -0400 Received: from pps.filterd (m0098416.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 045GW5d4174168; Tue, 5 May 2020 12:58:30 -0400 Received: from ppma03wdc.us.ibm.com (ba.79.3fa9.ip4.static.sl-reverse.com [169.63.121.186]) by mx0b-001b2d01.pphosted.com with ESMTP id 30s2g34xbn-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 05 May 2020 12:58:30 -0400 Received: from pps.filterd (ppma03wdc.us.ibm.com [127.0.0.1]) by ppma03wdc.us.ibm.com (8.16.0.27/8.16.0.27) with SMTP id 045GZXNV014501; Tue, 5 May 2020 16:58:30 GMT Received: from b03cxnp08025.gho.boulder.ibm.com (b03cxnp08025.gho.boulder.ibm.com [9.17.130.17]) by ppma03wdc.us.ibm.com with ESMTP id 30s0g6tae1-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 05 May 2020 16:58:30 +0000 Received: from b03ledav004.gho.boulder.ibm.com (b03ledav004.gho.boulder.ibm.com [9.17.130.235]) by b03cxnp08025.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 045GwSPK22020466 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 5 May 2020 16:58:28 GMT Received: from b03ledav004.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 10BB378063; Tue, 5 May 2020 16:58:29 +0000 (GMT) Received: from b03ledav004.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 7ABC77805F; Tue, 5 May 2020 16:58:28 +0000 (GMT) Received: from talon7.ibm.com (unknown [9.211.137.116]) by b03ledav004.gho.boulder.ibm.com (Postfix) with ESMTP; Tue, 5 May 2020 16:58:28 +0000 (GMT) From: Eddie James To: linux-aspeed@lists.ozlabs.org Cc: linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, robh+dt@kernel.org, joel@jms.id.au, andrew@aj.id.au, eajames@linux.ibm.com Subject: [PATCH v11 3/8] soc: aspeed: xdma: Add user interface Date: Tue, 5 May 2020 11:58:20 -0500 Message-Id: <1588697905-23444-4-git-send-email-eajames@linux.ibm.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1588697905-23444-1-git-send-email-eajames@linux.ibm.com> References: <1588697905-23444-1-git-send-email-eajames@linux.ibm.com> X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138, 18.0.676 definitions=2020-05-05_09:2020-05-04,2020-05-05 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxscore=0 malwarescore=0 suspectscore=4 bulkscore=0 priorityscore=1501 spamscore=0 lowpriorityscore=0 adultscore=0 phishscore=0 mlxlogscore=999 clxscore=1015 impostorscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2003020000 definitions=main-2005050126 Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org This commits adds a miscdevice to provide a user interface to the XDMA engine. The interface provides the write operation to start DMA operations. The DMA parameters are passed as the data to the write call. The actual data to transfer is NOT passed through write. Note that both directions of DMA operation are accomplished through the write command; BMC to host and host to BMC. The XDMA driver reserves an area of physical memory for DMA operations, as the XDMA engine is restricted to accessing certain physical memory areas on some platforms. This memory forms a pool from which users can allocate pages for their usage with calls to mmap. The space allocated by a client will be the space used in the DMA operation. For an "upstream" (BMC to host) operation, the data in the client's area will be transferred to the host. For a "downstream" (host to BMC) operation, the host data will be placed in the client's memory area. Poll is also provided in order to determine when the DMA operation is complete for non-blocking IO. Signed-off-by: Eddie James Reviewed-by: Andrew Jeffery --- drivers/soc/aspeed/aspeed-xdma.c | 218 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 218 insertions(+) diff --git a/drivers/soc/aspeed/aspeed-xdma.c b/drivers/soc/aspeed/aspeed-xdma.c index da78149..b4d4d34 100644 --- a/drivers/soc/aspeed/aspeed-xdma.c +++ b/drivers/soc/aspeed/aspeed-xdma.c @@ -13,6 +13,7 @@ #include #include #include +#include #include #include #include @@ -235,6 +236,8 @@ struct aspeed_xdma { dma_addr_t mem_coherent; dma_addr_t cmdq_phys; struct gen_pool *pool; + + struct miscdevice misc; }; struct aspeed_xdma_client { @@ -553,6 +556,211 @@ static irqreturn_t aspeed_xdma_pcie_irq(int irq, void *arg) return IRQ_HANDLED; } +static ssize_t aspeed_xdma_write(struct file *file, const char __user *buf, + size_t len, loff_t *offset) +{ + int rc; + unsigned int num_cmds; + struct aspeed_xdma_op op; + struct aspeed_xdma_cmd cmds[2]; + struct aspeed_xdma_client *client = file->private_data; + struct aspeed_xdma *ctx = client->ctx; + + if (len != sizeof(op)) + return -EINVAL; + + rc = copy_from_user(&op, buf, len); + if (rc) + return rc; + + if (!op.len || op.len > client->size || + op.direction > ASPEED_XDMA_DIRECTION_UPSTREAM) + return -EINVAL; + + num_cmds = ctx->chip->set_cmd(ctx, cmds, &op, client->phys); + do { + rc = aspeed_xdma_start(ctx, num_cmds, cmds, !!op.direction, + client); + if (!rc) + break; + + if ((file->f_flags & O_NONBLOCK) || rc != -EBUSY) + return rc; + + rc = wait_event_interruptible(ctx->wait, + !(ctx->current_client || + ctx->in_reset)); + } while (!rc); + + if (rc) + return -EINTR; + + if (!(file->f_flags & O_NONBLOCK)) { + rc = wait_event_interruptible(ctx->wait, !client->in_progress); + if (rc) + return -EINTR; + + if (client->error) + return -EIO; + } + + return len; +} + +static __poll_t aspeed_xdma_poll(struct file *file, + struct poll_table_struct *wait) +{ + __poll_t mask = 0; + __poll_t req = poll_requested_events(wait); + struct aspeed_xdma_client *client = file->private_data; + struct aspeed_xdma *ctx = client->ctx; + + if (req & (EPOLLIN | EPOLLRDNORM)) { + if (READ_ONCE(client->in_progress)) + poll_wait(file, &ctx->wait, wait); + + if (!READ_ONCE(client->in_progress)) { + if (READ_ONCE(client->error)) + mask |= EPOLLERR; + else + mask |= EPOLLIN | EPOLLRDNORM; + } + } + + if (req & (EPOLLOUT | EPOLLWRNORM)) { + if (READ_ONCE(ctx->current_client)) + poll_wait(file, &ctx->wait, wait); + + if (!READ_ONCE(ctx->current_client)) + mask |= EPOLLOUT | EPOLLWRNORM; + } + + return mask; +} + +static void aspeed_xdma_vma_close(struct vm_area_struct *vma) +{ + int rc; + struct aspeed_xdma_client *client = vma->vm_private_data; + + rc = wait_event_interruptible(client->ctx->wait, !client->in_progress); + if (rc) + return; + + gen_pool_free(client->ctx->pool, (unsigned long)client->virt, + client->size); + + client->virt = NULL; + client->phys = 0; + client->size = 0; +} + +static const struct vm_operations_struct aspeed_xdma_vm_ops = { + .close = aspeed_xdma_vma_close, +}; + +static int aspeed_xdma_mmap(struct file *file, struct vm_area_struct *vma) +{ + int rc; + struct aspeed_xdma_client *client = file->private_data; + struct aspeed_xdma *ctx = client->ctx; + + /* restrict file to one mapping */ + if (client->size) + return -EBUSY; + + client->size = vma->vm_end - vma->vm_start; + client->virt = gen_pool_dma_alloc(ctx->pool, client->size, + &client->phys); + if (!client->virt) { + client->phys = 0; + client->size = 0; + return -ENOMEM; + } + + vma->vm_pgoff = (client->phys - ctx->mem_phys) >> PAGE_SHIFT; + vma->vm_ops = &aspeed_xdma_vm_ops; + vma->vm_private_data = client; + vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); + + rc = io_remap_pfn_range(vma, vma->vm_start, client->phys >> PAGE_SHIFT, + client->size, vma->vm_page_prot); + if (rc) { + dev_warn(ctx->dev, "mmap err: v[%08lx] to p[%08x], s[%08x]\n", + vma->vm_start, (u32)client->phys, client->size); + + gen_pool_free(ctx->pool, (unsigned long)client->virt, + client->size); + + client->virt = NULL; + client->phys = 0; + client->size = 0; + return rc; + } + + dev_dbg(ctx->dev, "mmap: v[%08lx] to p[%08x], s[%08x]\n", + vma->vm_start, (u32)client->phys, client->size); + + return 0; +} + +static int aspeed_xdma_open(struct inode *inode, struct file *file) +{ + struct miscdevice *misc = file->private_data; + struct aspeed_xdma *ctx = container_of(misc, struct aspeed_xdma, misc); + struct aspeed_xdma_client *client = kzalloc(sizeof(*client), + GFP_KERNEL); + + if (!client) + return -ENOMEM; + + kobject_get(&ctx->kobj); + client->ctx = ctx; + file->private_data = client; + return 0; +} + +static int aspeed_xdma_release(struct inode *inode, struct file *file) +{ + bool reset = false; + unsigned long flags; + struct aspeed_xdma_client *client = file->private_data; + struct aspeed_xdma *ctx = client->ctx; + + spin_lock_irqsave(&ctx->client_lock, flags); + if (client == ctx->current_client) { + spin_lock(&ctx->engine_lock); + if (ctx->in_reset) { + ctx->current_client = NULL; + } else { + ctx->in_reset = true; + reset = true; + } + spin_unlock(&ctx->engine_lock); + } + spin_unlock_irqrestore(&ctx->client_lock, flags); + + if (reset) + aspeed_xdma_reset(ctx); + + if (client->virt) + gen_pool_free(ctx->pool, (unsigned long)client->virt, + client->size); + + kfree(client); + kobject_put(&ctx->kobj); + return 0; +} + +static const struct file_operations aspeed_xdma_fops = { + .owner = THIS_MODULE, + .write = aspeed_xdma_write, + .poll = aspeed_xdma_poll, + .mmap = aspeed_xdma_mmap, + .open = aspeed_xdma_open, + .release = aspeed_xdma_release, +}; + static int aspeed_xdma_init_scu(struct aspeed_xdma *ctx, struct device *dev) { struct regmap *scu = syscon_regmap_lookup_by_phandle(dev->of_node, @@ -814,6 +1022,16 @@ static int aspeed_xdma_probe(struct platform_device *pdev) aspeed_xdma_init_eng(ctx); + ctx->misc.minor = MISC_DYNAMIC_MINOR; + ctx->misc.fops = &aspeed_xdma_fops; + ctx->misc.name = "aspeed-xdma"; + ctx->misc.parent = dev; + rc = misc_register(&ctx->misc); + if (rc) { + dev_err(dev, "Failed to register xdma miscdevice.\n"); + goto err_misc; + } + /* * This interrupt could fire immediately so only request it once the * engine and driver are initialized.