From patchwork Wed Jan 15 21:29:45 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eddie James X-Patchwork-Id: 205659 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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=ham 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 AFF2AC32771 for ; Wed, 15 Jan 2020 21:30:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 864722081E for ; Wed, 15 Jan 2020 21:30:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729631AbgAOVak (ORCPT ); Wed, 15 Jan 2020 16:30:40 -0500 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:34632 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729442AbgAOVaV (ORCPT ); Wed, 15 Jan 2020 16:30:21 -0500 Received: from pps.filterd (m0098399.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 00FLRTko035784; Wed, 15 Jan 2020 16:30:02 -0500 Received: from ppma02dal.us.ibm.com (a.bd.3ea9.ip4.static.sl-reverse.com [169.62.189.10]) by mx0a-001b2d01.pphosted.com with ESMTP id 2xhm34umwr-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 15 Jan 2020 16:30:01 -0500 Received: from pps.filterd (ppma02dal.us.ibm.com [127.0.0.1]) by ppma02dal.us.ibm.com (8.16.0.27/8.16.0.27) with SMTP id 00FLR7GY017572; Wed, 15 Jan 2020 21:30:01 GMT Received: from b03cxnp07028.gho.boulder.ibm.com (b03cxnp07028.gho.boulder.ibm.com [9.17.130.15]) by ppma02dal.us.ibm.com with ESMTP id 2xf74pjj3v-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 15 Jan 2020 21:30:00 +0000 Received: from b03ledav001.gho.boulder.ibm.com (b03ledav001.gho.boulder.ibm.com [9.17.130.232]) by b03cxnp07028.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 00FLTxpQ53084554 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 15 Jan 2020 21:29:59 GMT Received: from b03ledav001.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 8936B6E050; Wed, 15 Jan 2020 21:29:59 +0000 (GMT) Received: from b03ledav001.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id A03466E04C; Wed, 15 Jan 2020 21:29:58 +0000 (GMT) Received: from talon7.ibm.com (unknown [9.41.103.158]) by b03ledav001.gho.boulder.ibm.com (Postfix) with ESMTP; Wed, 15 Jan 2020 21:29:58 +0000 (GMT) From: Eddie James To: linux-aspeed@lists.ozlabs.org Cc: linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, mark.rutland@arm.com, jason@lakedaemon.net, maz@kernel.org, robh+dt@kernel.org, tglx@linutronix.de, joel@jms.id.au, andrew@aj.id.au, eajames@linux.ibm.com Subject: [PATCH v6 07/12] soc: aspeed: xdma: Add user interface Date: Wed, 15 Jan 2020 15:29:45 -0600 Message-Id: <1579123790-6894-8-git-send-email-eajames@linux.ibm.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1579123790-6894-1-git-send-email-eajames@linux.ibm.com> References: <1579123790-6894-1-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, 18.0.572 definitions=2020-01-15_03:2020-01-15,2020-01-15 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 adultscore=0 phishscore=0 mlxlogscore=999 malwarescore=0 mlxscore=0 suspectscore=4 bulkscore=0 lowpriorityscore=0 impostorscore=0 priorityscore=1501 spamscore=0 clxscore=1015 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-1910280000 definitions=main-2001150161 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 --- drivers/soc/aspeed/aspeed-xdma.c | 200 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 200 insertions(+) diff --git a/drivers/soc/aspeed/aspeed-xdma.c b/drivers/soc/aspeed/aspeed-xdma.c index 3ca0795..1b81a08 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 @@ -222,6 +223,8 @@ struct aspeed_xdma { void __iomem *mem_virt; dma_addr_t cmdq_phys; struct gen_pool *pool; + + struct miscdevice misc; }; struct aspeed_xdma_client { @@ -530,6 +533,186 @@ 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; + + client->ctx = ctx; + file->private_data = client; + return 0; +} + +static int aspeed_xdma_release(struct inode *inode, struct file *file) +{ + struct aspeed_xdma_client *client = file->private_data; + + kfree(client); + 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, @@ -691,6 +874,22 @@ 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"); + + gen_pool_free(ctx->pool, (unsigned long)ctx->cmdq, + XDMA_CMDQ_SIZE); + + reset_control_assert(ctx->reset); + clk_disable_unprepare(ctx->clock); + return rc; + } + /* * This interrupt could fire immediately so only request it once the * engine and driver are initialized. @@ -712,6 +911,7 @@ static int aspeed_xdma_remove(struct platform_device *pdev) { struct aspeed_xdma *ctx = platform_get_drvdata(pdev); + misc_deregister(&ctx->misc); gen_pool_free(ctx->pool, (unsigned long)ctx->cmdq, XDMA_CMDQ_SIZE); reset_control_assert(ctx->reset);