From patchwork Mon Apr 20 20:26:07 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eddie James X-Patchwork-Id: 201726 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=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 7C06BC54FD0 for ; Mon, 20 Apr 2020 20:27:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6386020857 for ; Mon, 20 Apr 2020 20:27:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726839AbgDTU01 (ORCPT ); Mon, 20 Apr 2020 16:26:27 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:40462 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726743AbgDTU00 (ORCPT ); Mon, 20 Apr 2020 16:26:26 -0400 Received: from pps.filterd (m0098413.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 03KK2w70130264; Mon, 20 Apr 2020 16:26:18 -0400 Received: from ppma02wdc.us.ibm.com (aa.5b.37a9.ip4.static.sl-reverse.com [169.55.91.170]) by mx0b-001b2d01.pphosted.com with ESMTP id 30ghu66k55-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 20 Apr 2020 16:26:18 -0400 Received: from pps.filterd (ppma02wdc.us.ibm.com [127.0.0.1]) by ppma02wdc.us.ibm.com (8.16.0.27/8.16.0.27) with SMTP id 03KKPiM1010242; Mon, 20 Apr 2020 20:26:17 GMT Received: from b01cxnp23032.gho.pok.ibm.com (b01cxnp23032.gho.pok.ibm.com [9.57.198.27]) by ppma02wdc.us.ibm.com with ESMTP id 30fs66bk28-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 20 Apr 2020 20:26:17 +0000 Received: from b01ledav005.gho.pok.ibm.com (b01ledav005.gho.pok.ibm.com [9.57.199.110]) by b01cxnp23032.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 03KKQH7Z34013512 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 20 Apr 2020 20:26:17 GMT Received: from b01ledav005.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 02326AE05F; Mon, 20 Apr 2020 20:26:17 +0000 (GMT) Received: from b01ledav005.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 06EE3AE05C; Mon, 20 Apr 2020 20:26:16 +0000 (GMT) Received: from ghost4.ibm.com (unknown [9.163.56.120]) by b01ledav005.gho.pok.ibm.com (Postfix) with ESMTP; Mon, 20 Apr 2020 20:26:15 +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 v10 3/7] soc: aspeed: xdma: Add user interface Date: Mon, 20 Apr 2020 15:26:07 -0500 Message-Id: <20200420202611.17776-4-eajames@linux.ibm.com> X-Mailer: git-send-email 2.24.0 In-Reply-To: <20200420202611.17776-1-eajames@linux.ibm.com> References: <20200420202611.17776-1-eajames@linux.ibm.com> MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138, 18.0.676 definitions=2020-04-20_07:2020-04-20,2020-04-20 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxlogscore=999 suspectscore=4 bulkscore=0 spamscore=0 phishscore=0 adultscore=0 clxscore=1015 malwarescore=0 priorityscore=1501 lowpriorityscore=0 mlxscore=0 impostorscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2003020000 definitions=main-2004200155 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 | 200 ++++++++++++++++++++++++++++++- 1 file changed, 198 insertions(+), 2 deletions(-) diff --git a/drivers/soc/aspeed/aspeed-xdma.c b/drivers/soc/aspeed/aspeed-xdma.c index bf9577da734e..adfb9e13c8b9 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 @@ -229,6 +230,8 @@ struct aspeed_xdma { void *mem_virt; dma_addr_t cmdq_phys; struct gen_pool *pool; + + struct miscdevice misc; }; struct aspeed_xdma_client { @@ -563,6 +566,187 @@ 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; + + kref_init(&client->kref); + 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; + + kref_put(&client->kref, aspeed_xdma_client_release); + 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, @@ -762,6 +946,18 @@ 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); + goto err; + } + /* * This interrupt could fire immediately so only request it once the * engine and driver are initialized. @@ -792,8 +988,8 @@ static int aspeed_xdma_remove(struct platform_device *pdev) { struct aspeed_xdma *ctx = platform_get_drvdata(pdev); - gen_pool_free(ctx->pool, (unsigned long)ctx->cmdq_virt, - XDMA_CMDQ_SIZE); + misc_deregister(&ctx->misc); + gen_pool_free(ctx->pool, (unsigned long)ctx->cmdq, XDMA_CMDQ_SIZE); reset_control_assert(ctx->reset); if (ctx->reset_rc)