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[2620:137:e000::1:20]) by mx.google.com with ESMTP id u3-20020a17090341c300b0015d21512abfsi28048374ple.527.2022.06.07.03.27.41; Tue, 07 Jun 2022 03:27:56 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=arm.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232448AbiFGIdi (ORCPT + 99 others); Tue, 7 Jun 2022 04:33:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50366 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232373AbiFGIdg (ORCPT ); Tue, 7 Jun 2022 04:33:36 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id B94B223BC4 for ; Tue, 7 Jun 2022 01:33:33 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 95A2A143D; Tue, 7 Jun 2022 01:33:33 -0700 (PDT) Received: from [10.57.83.83] (unknown [10.57.83.83]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 398563F73B; Tue, 7 Jun 2022 01:33:32 -0700 (PDT) Message-ID: <4c4af59c-0b71-c5a5-1d5c-80b2e89de4d9@arm.com> Date: Tue, 7 Jun 2022 09:33:30 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:91.0) Gecko/20100101 Thunderbird/91.10.0 Subject: Re: [PATCH v6 1/2] drivers/coresight: Add UltraSoc System Memory Buffer driver To: Qi Liu , mathieu.poirier@linaro.org, mike.leach@linaro.org Cc: coresight@lists.linaro.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linuxarm@huawei.com References: <20220606130223.57354-1-liuqi115@huawei.com> <20220606130223.57354-2-liuqi115@huawei.com> From: Suzuki K Poulose In-Reply-To: <20220606130223.57354-2-liuqi115@huawei.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Status: No, score=-8.1 required=5.0 tests=BAYES_00,NICE_REPLY_A, RCVD_IN_DNSWL_HI,SPF_HELO_NONE,SPF_NONE,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Qi On 06/06/2022 14:02, Qi Liu wrote: > This patch adds driver for UltraSoc SMB(System Memory Buffer) > device. SMB provides a way to buffer messages from ETM, and > store these CPU instructions in system memory. nit: "CPU instruction trace" in system memory. > > SMB is developed by UltraSoc technology, which is acquired by > Siemens, and we still use "UltraSoc" to name driver. > > Signed-off-by: Qi Liu > Tested-by: JunHao He > --- > drivers/hwtracing/coresight/Kconfig | 10 + > drivers/hwtracing/coresight/Makefile | 1 + > drivers/hwtracing/coresight/ultrasoc-smb.c | 663 +++++++++++++++++++++ > drivers/hwtracing/coresight/ultrasoc-smb.h | 110 ++++ > 4 files changed, 784 insertions(+) > create mode 100644 drivers/hwtracing/coresight/ultrasoc-smb.c > create mode 100644 drivers/hwtracing/coresight/ultrasoc-smb.h > > diff --git a/drivers/hwtracing/coresight/Kconfig b/drivers/hwtracing/coresight/Kconfig > index 514a9b8086e3..4380eb1a0a73 100644 > --- a/drivers/hwtracing/coresight/Kconfig > +++ b/drivers/hwtracing/coresight/Kconfig ... > diff --git a/drivers/hwtracing/coresight/Makefile b/drivers/hwtracing/coresight/Makefile > index b6c4a48140ec..344dba8d6ff8 100644 > --- a/drivers/hwtracing/coresight/Makefile > +++ b/drivers/hwtracing/coresight/Makefile > @@ -27,3 +27,4 @@ obj-$(CONFIG_CORESIGHT_CTI) += coresight-cti.o > obj-$(CONFIG_CORESIGHT_TRBE) += coresight-trbe.o > coresight-cti-y := coresight-cti-core.o coresight-cti-platform.o \ > coresight-cti-sysfs.o > +obj-$(CONFIG_ULTRASOC_SMB) += ultrasoc-smb.o > diff --git a/drivers/hwtracing/coresight/ultrasoc-smb.c b/drivers/hwtracing/coresight/ultrasoc-smb.c > new file mode 100644 > index 000000000000..44b4bceb6f28 > --- /dev/null > +++ b/drivers/hwtracing/coresight/ultrasoc-smb.c ... > +static int smb_open(struct inode *inode, struct file *file) > +{ > + struct smb_drv_data *drvdata = container_of(file->private_data, > + struct smb_drv_data, miscdev); > + unsigned long flags; > + int ret = 0; > + > + spin_lock_irqsave(&drvdata->spinlock, flags); > + > + if (local_read(&drvdata->reading)) { > + ret = -EBUSY; > + goto out; > + } > + > + if (drvdata->mode == CS_MODE_PERF) { > + ret = -EINVAL; > + goto out; > + } > + > +out: > + spin_unlock_irqrestore(&drvdata->spinlock, flags); > + return ret; > +} > + > +static ssize_t smb_read(struct file *file, char __user *data, size_t len, > + loff_t *ppos) > +{ > + struct smb_drv_data *drvdata = container_of(file->private_data, > + struct smb_drv_data, miscdev); > + struct smb_data_buffer *sdb = &drvdata->sdb; > + struct device *dev = &drvdata->csdev->dev; > + unsigned long flags; > + int to_copy = 0; > + > + spin_lock_irqsave(&drvdata->spinlock, flags); > + > + if (atomic_read(drvdata->csdev->refcnt)) { > + spin_unlock_irqrestore(&drvdata->spinlock, flags); > + return -EBUSY; > + } > + > + if (local_cmpxchg(&drvdata->reading, 0, 1)) { > + spin_unlock_irqrestore(&drvdata->spinlock, flags); > + return -EBUSY; > + } > + Shouldn't this be done in smb_open() ? Otherwise, a subsequent read will fail with EBUSY ? i.e, fd = open(/dev/ultra_smb0, ..); # size of the SMB buffer = 1M, size = read(fd, buf, SZ_4K); /* Do something the buf */ if (size >= 0) size = read(fd, buf, SZ_4K); ^^ This would fail, isn't it ? > + if (!sdb->data_size) { > + smb_update_data_size(drvdata); > + if (!sdb->data_size) > + goto out; > + } > + > + to_copy = min(sdb->data_size, len); > + > + /* Copy parts of trace data when read pointer wrap around SMB buffer */ > + if (sdb->rd_offset + to_copy > sdb->buf_size) > + to_copy = sdb->buf_size - sdb->rd_offset; > + > + if (copy_to_user(data, (void *)sdb->buf_base + sdb->rd_offset, > + to_copy)) { > + dev_dbg(dev, "Failed to copy data to user.\n"); > + to_copy = -EFAULT; > + goto out; > + } > + > + *ppos += to_copy; > + sdb->data_size -= to_copy; > + sdb->rd_offset += to_copy; > + sdb->rd_offset %= sdb->buf_size; > + writel(sdb->start_addr + sdb->rd_offset, > + drvdata->base + SMB_LB_RD_ADDR); > + dev_dbg(dev, "%d bytes copied.\n", to_copy); > +out: > + if (!sdb->data_size) > + smb_reset_buffer_status(drvdata); > + spin_unlock_irqrestore(&drvdata->spinlock, flags); > + return to_copy; > +} > + > +static int smb_release(struct inode *inode, struct file *file) > +{ > + struct smb_drv_data *drvdata = container_of(file->private_data, > + struct smb_drv_data, miscdev); > + local_set(&drvdata->reading, 0); > + return 0; > +} > + > +static const struct file_operations smb_fops = { > + .owner = THIS_MODULE, > + .open = smb_open, > + .read = smb_read, > + .release = smb_release, > + .llseek = no_llseek, > +}; > + > +smb_reg(read_pos, SMB_LB_RD_ADDR); > +smb_reg(write_pos, SMB_LB_WR_ADDR); > +smb_reg(buf_status, SMB_LB_INT_STS); > + > +static ssize_t buf_size_show(struct device *dev, struct device_attribute *attr, > + char *buf) > +{ > + struct smb_drv_data *drvdata = dev_get_drvdata(dev->parent); > + > + return sysfs_emit(buf, "0x%lx\n", drvdata->sdb.buf_size); > +} > +static DEVICE_ATTR_RO(buf_size); > + > +static struct attribute *smb_sink_attrs[] = { > + &dev_attr_read_pos.attr, > + &dev_attr_write_pos.attr, > + &dev_attr_buf_status.attr, > + &dev_attr_buf_size.attr, > + NULL, > +}; > + > +static const struct attribute_group smb_sink_group = { > + .attrs = smb_sink_attrs, > + .name = "mgmt", > +}; > + > +static const struct attribute_group *smb_sink_groups[] = { > + &smb_sink_group, > + NULL, > +}; > + > +static int smb_set_perf_buffer(struct perf_output_handle *handle) > +{ > + struct cs_buffers *buf = etm_perf_sink_config(handle); > + u32 head; > + > + if (!buf) > + return -EINVAL; > + > + /* Wrap head around to the amount of space we have */ > + head = handle->head & ((buf->nr_pages << PAGE_SHIFT) - 1); > + > + /* Find the page to write to and offset within that page */ > + buf->cur = head / PAGE_SIZE; > + buf->offset = head % PAGE_SIZE; > + I believe these fields should be dropped and instead use the handle->head, to determine the page number and offset. See the TMC-ETR driver for e.g. > + local_set(&buf->data_size, 0); > + > + return 0; > +} > + > +static void smb_enable_hw(struct smb_drv_data *drvdata) > +{ > + writel(0x1, drvdata->base + SMB_GLOBAL_EN); > +} > + > +static void smb_disable_hw(struct smb_drv_data *drvdata) > +{ > + writel(0x0, drvdata->base + SMB_GLOBAL_EN); > +} > + > +static int smb_enable_sysfs(struct coresight_device *csdev) > +{ > + struct smb_drv_data *drvdata = dev_get_drvdata(csdev->dev.parent); > + unsigned long flags; > + int ret = 0; > + > + spin_lock_irqsave(&drvdata->spinlock, flags); > + if (drvdata->mode == CS_MODE_PERF) { > + ret = -EBUSY; > + goto out; > + } > + > + if (drvdata->mode == CS_MODE_DISABLED) { > + smb_enable_hw(drvdata); > + drvdata->mode = CS_MODE_SYSFS; > + } > + > + atomic_inc(csdev->refcnt); > +out: > + spin_unlock_irqrestore(&drvdata->spinlock, flags); > + return ret; > +} > + > +static int smb_enable_perf(struct coresight_device *csdev, void *data) > +{ > + struct smb_drv_data *drvdata = dev_get_drvdata(csdev->dev.parent); > + struct device *dev = &drvdata->csdev->dev; > + struct perf_output_handle *handle = data; > + struct cs_buffers *buf = etm_perf_sink_config(handle); > + unsigned long flags; > + int ret = 0; > + pid_t pid; > + > + spin_lock_irqsave(&drvdata->spinlock, flags); > + if (drvdata->mode == CS_MODE_SYSFS) { > + dev_dbg(dev, "Device is already in used by sysfs.\n"); > + ret = -EBUSY; > + goto out; > + } > + > + /* Get a handle on the pid of the target process */ > + pid = buf->pid; > + if (drvdata->pid != -1 && drvdata->pid != pid) { > + dev_dbg(dev, "Device is already in used by other session.\n"); > + ret = -EBUSY; > + goto out; > + } > + > + /* The sink is already enabled by this session */ > + if (drvdata->pid == pid) { > + atomic_inc(csdev->refcnt); > + goto out; > + } > + > + ret = smb_set_perf_buffer(handle); > + if (ret) > + goto out; > + > + smb_enable_hw(drvdata); > + drvdata->pid = pid; > + drvdata->mode = CS_MODE_PERF; > + atomic_inc(csdev->refcnt); > +out: > + spin_unlock_irqrestore(&drvdata->spinlock, flags); > + return ret; > +} > + > +static int smb_enable(struct coresight_device *csdev, u32 mode, void *data) > +{ > + struct smb_drv_data *drvdata = dev_get_drvdata(csdev->dev.parent); > + int ret; > + > + /* Do nothing if trace data is reading by other interface now */ > + if (local_read(&drvdata->reading)) > + return -EBUSY; > + Is there global switch for all the inports ? Or is there a control for individual inports to the SMB ? Do we need additional information here to enable the corresponding port ? > + switch (mode) { > + case CS_MODE_SYSFS: > + ret = smb_enable_sysfs(csdev); > + break; > + case CS_MODE_PERF: > + ret = smb_enable_perf(csdev, data); > + break; > + default: > + ret = -EINVAL; > + break; > + } > + > + if (ret) > + return ret; > + dev_dbg(&csdev->dev, "Ultrasoc SMB enabled.\n"); > + > + return 0; > +} > + > +static int smb_disable(struct coresight_device *csdev) > +{ > + struct smb_drv_data *drvdata = dev_get_drvdata(csdev->dev.parent); > + unsigned long flags; > + > + spin_lock_irqsave(&drvdata->spinlock, flags); > + > + if (local_read(&drvdata->reading)) { > + spin_unlock_irqrestore(&drvdata->spinlock, flags); > + return -EBUSY; > + } > + > + if (atomic_dec_return(csdev->refcnt)) { > + spin_unlock_irqrestore(&drvdata->spinlock, flags); > + return -EBUSY; > + } > + > + WARN_ON_ONCE(drvdata->mode == CS_MODE_DISABLED); > + smb_disable_hw(drvdata); > + smb_purge_data(drvdata); > + > + /* Dissociate from the target process. */ > + drvdata->pid = -1; > + drvdata->mode = CS_MODE_DISABLED; > + spin_unlock_irqrestore(&drvdata->spinlock, flags); > + > + dev_dbg(&csdev->dev, "Ultrasoc SMB disabled.\n"); > + return 0; > +} > + > +static void *smb_alloc_buffer(struct coresight_device *csdev, > + struct perf_event *event, void **pages, > + int nr_pages, bool overwrite) > +{ > + struct cs_buffers *buf; > + int node; > + > + node = (event->cpu == -1) ? NUMA_NO_NODE : cpu_to_node(event->cpu); > + buf = kzalloc_node(sizeof(struct cs_buffers), GFP_KERNEL, node); > + if (!buf) > + return NULL; > + > + buf->snapshot = overwrite; > + buf->nr_pages = nr_pages; > + buf->data_pages = pages; > + buf->pid = task_pid_nr(event->owner); > + > + return buf; > +} > + > +static void smb_free_buffer(void *config) > +{ > + struct cs_buffers *buf = config; > + > + kfree(buf); > +} > + > +static void smb_sync_perf_buffer(struct smb_drv_data *drvdata, > + struct cs_buffers *buf, > + unsigned long data_size) You may need to pass the aux_handle here, to determine the handle->head and the size. See my comments above. > +{ > + struct smb_data_buffer *sdb = &drvdata->sdb; > + char **dst_pages = (char **)buf->data_pages; > + unsigned long page_offset = buf->offset; > + unsigned int cur = buf->cur; > + unsigned long to_copy; > + > + while (data_size) { > + unsigned long page_space = PAGE_SIZE - page_offset; > + > + /* Copy parts of trace data when read pointer wrap around */ > + if (sdb->rd_offset + page_space > sdb->buf_size) > + to_copy = sdb->buf_size - sdb->rd_offset; > + else > + to_copy = min(data_size, page_space); > + > + memcpy_fromio(dst_pages[cur] + page_offset, > + sdb->buf_base + sdb->rd_offset, to_copy); > + > + page_offset += to_copy; > + if (page_offset >= PAGE_SIZE) { > + page_offset = 0; > + cur++; > + cur %= buf->nr_pages; > + } > + data_size -= to_copy; > + sdb->rd_offset += to_copy; > + sdb->rd_offset %= sdb->buf_size; > + } > + > + sdb->data_size = 0; > + writel(sdb->start_addr + sdb->rd_offset, drvdata->base + SMB_LB_RD_ADDR); > + > + /* > + * Data remained in link cannot be purged when SMB is full, so > + * synchronize the read pointer to write pointer, to make sure > + * these remained data won't influence next trace. > + */ > + if (sdb->full) { > + smb_purge_data(drvdata); > + writel(readl(drvdata->base + SMB_LB_WR_ADDR), > + drvdata->base + SMB_LB_RD_ADDR); > + } > + smb_reset_buffer_status(drvdata); > +} > + > +static unsigned long smb_update_buffer(struct coresight_device *csdev, > + struct perf_output_handle *handle, > + void *sink_config) > +{ > + struct smb_drv_data *drvdata = dev_get_drvdata(csdev->dev.parent); > + struct smb_data_buffer *sdb = &drvdata->sdb; > + struct cs_buffers *buf = sink_config; > + unsigned long data_size = 0; > + unsigned long flags; > + bool lost = false; > + > + if (!buf) > + return 0; > + > + spin_lock_irqsave(&drvdata->spinlock, flags); > + > + /* Don't do anything if another tracer is using this sink. */ > + if (atomic_read(csdev->refcnt) != 1) > + goto out; > + > + smb_disable_hw(drvdata); > + smb_update_data_size(drvdata); > + data_size = sdb->data_size; > + > + /* > + * The SMB buffer may be bigger than the space available in the > + * perf ring buffer (handle->size). If so advance the offset so > + * that we get the latest trace data. > + */ > + if (data_size > handle->size) { > + sdb->rd_offset += data_size - handle->size; > + sdb->rd_offset %= sdb->buf_size; > + data_size = handle->size; > + lost = true; > + } > + > + smb_sync_perf_buffer(drvdata, buf, data_size); > + if (!buf->snapshot && lost) > + perf_aux_output_flag(handle, PERF_AUX_FLAG_TRUNCATED); > + > + smb_enable_hw(drvdata); > +out: > + spin_unlock_irqrestore(&drvdata->spinlock, flags); > + return data_size; > +} > + > +static const struct coresight_ops_sink smb_cs_ops = { > + .enable = smb_enable, > + .disable = smb_disable, > + .alloc_buffer = smb_alloc_buffer, > + .free_buffer = smb_free_buffer, > + .update_buffer = smb_update_buffer, > +}; > + > +static const struct coresight_ops cs_ops = { > + .sink_ops = &smb_cs_ops, > +}; > + > +static int smb_init_data_buffer(struct platform_device *pdev, > + struct smb_data_buffer *sdb) > +{ > + struct resource *res; > + void __iomem *base; > + > + res = platform_get_resource(pdev, IORESOURCE_MEM, 1); > + if (IS_ERR(res)) { > + dev_err(&pdev->dev, "SMB device failed to get resource.\n"); > + return -EINVAL; > + } > + > + sdb->start_addr = res->start & SMB_BASE_LOW_MASK; > + sdb->buf_size = resource_size(res); > + if (sdb->buf_size == 0) > + return -EINVAL; > + > + base = devm_ioremap_resource(&pdev->dev, res); > + if (IS_ERR(base)) > + return PTR_ERR(base); > + > + sdb->buf_base = base; > + > + return 0; > +} > + > +static void smb_init_hw(struct smb_drv_data *drvdata) > +{ > + /* First disable smb and clear the status of SMB buffer */ > + smb_reset_buffer_status(drvdata); > + smb_disable_hw(drvdata); > + smb_purge_data(drvdata); > + > + writel(SMB_BUF_CFG_STREAMING, drvdata->base + SMB_LB_CFG_LO); > + writel(SMB_MSG_FILTER, drvdata->base + SMB_LB_CFG_HI); > + writel(SMB_GLOBAL_CFG, drvdata->base + SMB_CFG_REG); > + writel(SMB_GLB_INT_CFG, drvdata->base + SMB_GLOBAL_INT); > + writel(SMB_BUF_INT_CFG, drvdata->base + SMB_LB_INT_CTRL); > +} > + > +static int smb_register_sink(struct platform_device *pdev, > + struct smb_drv_data *drvdata) > +{ > + struct coresight_platform_data *pdata = NULL; > + struct coresight_desc desc = { 0 }; > + int ret; > + > + pdata = coresight_get_platform_data(&pdev->dev); > + if (IS_ERR(pdata)) > + return PTR_ERR(pdata); > + > + desc.type = CORESIGHT_DEV_TYPE_SINK; > + desc.subtype.sink_subtype = CORESIGHT_DEV_SUBTYPE_SINK_BUFFER; > + desc.ops = &cs_ops; > + desc.pdata = pdata; > + desc.dev = &pdev->dev; > + desc.groups = smb_sink_groups; > + desc.name = coresight_alloc_device_name(&sink_devs, &pdev->dev); Please fill in the csdev_access method for the device. desc.access = CSDEV_ACCESS_IOMEM(drvdata->base); > + if (!desc.name) { > + dev_err(&pdev->dev, "Failed to alloc coresight device name."); > + return -ENOMEM; > + } > + > + drvdata->csdev = coresight_register(&desc); > + if (IS_ERR(drvdata->csdev)) > + return PTR_ERR(drvdata->csdev); > + > + drvdata->miscdev.name = desc.name; > + drvdata->miscdev.minor = MISC_DYNAMIC_MINOR; > + drvdata->miscdev.fops = &smb_fops; > + ret = misc_register(&drvdata->miscdev); > + if (ret) { > + coresight_unregister(drvdata->csdev); > + dev_err(&pdev->dev, "Failed to register misc, ret=%d.\n", ret); > + } > + > + return ret; > +} > + > +static void smb_unregister_sink(struct smb_drv_data *drvdata) > +{ > + misc_deregister(&drvdata->miscdev); > + coresight_unregister(drvdata->csdev); > +} > + > +static int smb_config_inport(struct device *dev, bool enable) > +{ > + u64 func = enable ? 1 : 0; > + union acpi_object *obj; > + guid_t guid; > + u64 rev = 0; > + > + /* > + * Using DSM calls to enable/disable ultrasoc hardwares on > + * tracing path, to prevent ultrasoc packet format being exposed. > + */ > + if (guid_parse(ULTRASOC_SMB_DSM_UUID, &guid)) { > + dev_err(dev, "Get GUID failed.\n"); > + return -EINVAL; > + } > + > + obj = acpi_evaluate_dsm(ACPI_HANDLE(dev), &guid, rev, func, NULL); > + if (!obj) > + dev_err(dev, "ACPI handle failed!\n"); > + else > + ACPI_FREE(obj); > + > + return 0; > +} > + > +static int smb_probe(struct platform_device *pdev) > +{ > + struct smb_drv_data *drvdata; > + int ret; > + > + drvdata = devm_kzalloc(&pdev->dev, sizeof(*drvdata), GFP_KERNEL); > + if (!drvdata) > + return -ENOMEM; > + > + drvdata->base = devm_platform_ioremap_resource(pdev, 0); > + if (IS_ERR(drvdata->base)) { > + dev_err(&pdev->dev, "Failed to ioremap resource.\n"); > + return PTR_ERR(drvdata->base); > + } > + > + ret = smb_init_data_buffer(pdev, &drvdata->sdb); > + if (ret) { > + dev_err(&pdev->dev, "Failed to init buffer, ret = %d.\n", ret); > + return ret; > + } > + > + smb_init_hw(drvdata); > + spin_lock_init(&drvdata->spinlock); > + drvdata->pid = -1; > + > + ret = smb_register_sink(pdev, drvdata); > + if (ret) { > + dev_err(&pdev->dev, "Failed to register smb sink.\n"); > + return ret; > + } > + > + ret = smb_config_inport(&pdev->dev, true); > + if (ret) { > + smb_unregister_sink(drvdata); > + return ret; > + } > + > + platform_set_drvdata(pdev, drvdata); > + return 0; > +} > + > +static int smb_remove(struct platform_device *pdev) > +{ > + struct smb_drv_data *drvdata = platform_get_drvdata(pdev); > + int ret; > + > + ret = smb_config_inport(&pdev->dev, false); > + if (ret) > + return ret; > + > + smb_unregister_sink(drvdata); > + return 0; > +} > + > +static const struct acpi_device_id ultrasoc_smb_acpi_match[] = { > + {"HISI03A1", 0}, > + {}, > +}; > +MODULE_DEVICE_TABLE(acpi, ultrasoc_smb_acpi_match); > + > +static struct platform_driver smb_driver = { > + .driver = { > + .name = "ultrasoc-smb", > + .acpi_match_table = ACPI_PTR(ultrasoc_smb_acpi_match), > + .suppress_bind_attrs = true, > + }, > + .probe = smb_probe, > + .remove = smb_remove, > +}; > +module_platform_driver(smb_driver); > + > +MODULE_DESCRIPTION("UltraSoc smb driver"); "UltraSoc SMB CoreSight driver" > +MODULE_LICENSE("Dual MIT/GPL"); > +MODULE_AUTHOR("Jonathan Zhou "); > +MODULE_AUTHOR("Qi Liu "); > diff --git a/drivers/hwtracing/coresight/ultrasoc-smb.h b/drivers/hwtracing/coresight/ultrasoc-smb.h > new file mode 100644 > index 000000000000..a01f869fe122 > --- /dev/null > +++ b/drivers/hwtracing/coresight/ultrasoc-smb.h > @@ -0,0 +1,110 @@ > +/* SPDX-License-Identifier: (GPL-2.0 OR MIT) */ > +/* > + * Siemens System Memory Buffer driver. > + * Copyright(c) 2021, HiSilicon Limited. > + */ > + > +#ifndef _ULTRASOC_SMB_H > +#define _ULTRASOC_SMB_H > + > +#include > +#include > +#include > + > +#include "coresight-etm-perf.h" > +#include "coresight-priv.h" > + > +/* Offset of SMB logical buffer registers */ > +#define SMB_CFG_REG 0x00 > +#define SMB_GLOBAL_EN 0x04 > +#define SMB_GLOBAL_INT 0x08 > +#define SMB_LB_CFG_LO 0x40 > +#define SMB_LB_CFG_HI 0x44 > +#define SMB_LB_INT_CTRL 0x48 > +#define SMB_LB_INT_STS 0x4c > +#define SMB_LB_LIMIT 0x58 > +#define SMB_LB_RD_ADDR 0x5c > +#define SMB_LB_WR_ADDR 0x60 > +#define SMB_LB_PURGE 0x64 > + > +/* Set SMB_CFG_REG register */ > +#define SMB_BURST_LEN GENMASK(7, 4) > +#define SMB_IDLE_PRD GENMASK(15, 12) > +#define SMB_MEM_WR GENMASK(17, 16) > +#define SMB_MEM_RD (GENMASK(26, 25) | GENMASK(23, 22)) > +#define SMB_GLOBAL_CFG (SMB_IDLE_PRD | SMB_MEM_WR | SMB_MEM_RD | \ > + SMB_BURST_LEN) > + > +/* Set SMB_GLOBAL_INT register */ > +#define SMB_INT_EN BIT(0) > +#define SMB_INT_TYPE_PULSE BIT(1) > +#define SMB_INT_POLARITY_HIGH BIT(2) > +#define SMB_GLB_INT_CFG (SMB_INT_EN | SMB_INT_TYPE_PULSE | \ > + SMB_INT_POLARITY_HIGH) > + > +/* Set SMB_LB_CFG_LO register */ > +#define SMB_BUF_EN BIT(0) > +#define SMB_BUF_SINGLE_END BIT(1) > +#define SMB_BUF_INIT BIT(8) > +#define SMB_BUF_CONTINUOUS BIT(11) > +#define SMB_FLOW_MASK GENMASK(19, 16) What does the value GENMASK(19, 16) indicate for SMB_FLOW ? That is the value being passed down. Please add a descriptive name. .e.g, #define SMB_FLOW_MODE_X GENMASK(19, 16) Similarly for SMB_BUF_NOTE_MASK, unless there is an explanation. > +#define SMB_BUF_CFG_STREAMING (SMB_BUF_INIT | SMB_BUF_CONTINUOUS | \ > + SMB_FLOW_MASK | SMB_BUF_SINGLE_END | \ > + SMB_BUF_EN) > + > +#define SMB_BASE_LOW_MASK GENMASK(31, 0) > + > +/* Set SMB_LB_CFG_HI register */ > +#define SMB_MSG_FILTER GENMASK(15, 8) > + > +/* Set SMB_LB_INT_CTRL */ > +#define SMB_BUF_INT_EN BIT(0) > +#define SMB_BUF_NOTE_MASK GENMASK(11, 8) > +#define SMB_BUF_INT_CFG (SMB_BUF_INT_EN | SMB_BUF_NOTE_MASK) > + > +/** > + * struct smb_data_buffer - Details of the buffer used by SMB > + * @buf_base : Memory mapped base address of SMB. > + * @start_addr : SMB buffer start Physical address. > + * @buf_size : Size of the buffer. Please align the field definitions. > + * @data_size : Size of Trace data copy to userspace. > + * @rd_offset : Offset of the read pointer in the buffer. > + * @wr_offset : Offset of the write pointer in the buffer. > + * @status : Status of SMB buffer. > + */ > +struct smb_data_buffer { > + void __iomem *buf_base; > + u32 start_addr; > + unsigned long buf_size; > + unsigned long data_size; > + unsigned long rd_offset; > + unsigned long wr_offset; > + bool full; > +}; > + > +/** > + * struct smb_drv_data - specifics associated to an SMB component > + * @base: Memory mapped base address for SMB component. > + * @csdev: Component vitals needed by the framework. > + * @sdb: Data buffer for SMB. > + * @miscdev: Specifics to handle "/dev/xyz.smb" entry. > + * @spinlock: Only one at a time pls. > + * @reading: Synchronise user space access to SMB buffer. > + * @pid: Process ID of the process being monitored by the session > + * that is using this component. Same as above. > + * @mode: how this SMB is being used, perf mode or sysfs mode. > + */ > +struct smb_drv_data { > + void __iomem *base; > + struct coresight_device *csdev; > + struct smb_data_buffer sdb; > + struct miscdevice miscdev; > + spinlock_t spinlock; > + local_t reading; > + pid_t pid; > + u32 mode; > +}; > + > +#define smb_reg(name, offset) coresight_simple_reg32(struct smb_drv_data, name, offset) > + > +#endif Suzuki