// SPDX-License-Identifier: (GPL-2.0 OR MIT) /* * Siemens System Memory Buffer driver. * Copyright(c) 2022, HiSilicon Limited. */ #include #include #include #include #include #include #include #include #include "coresight-etm-perf.h" #include "coresight-priv.h" #include "ultrasoc-smb.h" DEFINE_CORESIGHT_DEVLIST(sink_devs, "ultra_smb"); #define ULTRASOC_SMB_DSM_UUID "82ae1283-7f6a-4cbe-aa06-53e8fb24db18" static bool smb_buffer_not_empty(struct smb_drv_data *drvdata) { u32 buf_status = readl(drvdata->base + SMB_LB_INT_STS_REG); return FIELD_GET(SMB_LB_INT_STS_NOT_EMPTY_MSK, buf_status); } static void smb_update_data_size(struct smb_drv_data *drvdata) { struct smb_data_buffer *sdb = &drvdata->sdb; u32 buf_wrptr; buf_wrptr = readl(drvdata->base + SMB_LB_WR_ADDR_REG) - sdb->buf_hw_base; /* Buffer is full */ if (buf_wrptr == sdb->buf_rdptr && smb_buffer_not_empty(drvdata)) { sdb->data_size = sdb->buf_size; return; } /* The buffer mode is circular buffer mode */ sdb->data_size = CIRC_CNT(buf_wrptr, sdb->buf_rdptr, sdb->buf_size); } /* * The read pointer adds @nbytes bytes (may round up to the beginning) * after the data is read or discarded, while needing to update the * available data size. */ static void smb_update_read_ptr(struct smb_drv_data *drvdata, u32 nbytes) { struct smb_data_buffer *sdb = &drvdata->sdb; sdb->buf_rdptr += nbytes; sdb->buf_rdptr %= sdb->buf_size; writel(sdb->buf_hw_base + sdb->buf_rdptr, drvdata->base + SMB_LB_RD_ADDR_REG); sdb->data_size -= nbytes; } static void smb_reset_buffer(struct smb_drv_data *drvdata) { struct smb_data_buffer *sdb = &drvdata->sdb; u32 write_ptr; /* * We must flush and discard any data left in hardware path * to avoid corrupting the next session. * Note: The write pointer will never exceed the read pointer. */ writel(SMB_LB_PURGE_PURGED, drvdata->base + SMB_LB_PURGE_REG); /* Reset SMB logical buffer status flags */ writel(SMB_LB_INT_STS_RESET, drvdata->base + SMB_LB_INT_STS_REG); write_ptr = readl(drvdata->base + SMB_LB_WR_ADDR_REG); /* Do nothing, not data left in hardware path */ if (!write_ptr || write_ptr == sdb->buf_rdptr + sdb->buf_hw_base) return; /* * The SMB_LB_WR_ADDR_REG register is read-only, * Synchronize the read pointer to write pointer. */ writel(write_ptr, drvdata->base + SMB_LB_RD_ADDR_REG); sdb->buf_rdptr = write_ptr - sdb->buf_hw_base; } 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); guard(spinlock)(&drvdata->spinlock); if (drvdata->reading) return -EBUSY; if (atomic_read(&drvdata->csdev->refcnt)) return -EBUSY; smb_update_data_size(drvdata); drvdata->reading = true; return 0; } 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; ssize_t to_copy = 0; if (!len) return 0; if (!sdb->data_size) return 0; to_copy = min(sdb->data_size, len); /* Copy parts of trace data when read pointer wrap around SMB buffer */ if (sdb->buf_rdptr + to_copy > sdb->buf_size) to_copy = sdb->buf_size - sdb->buf_rdptr; if (copy_to_user(data, sdb->buf_base + sdb->buf_rdptr, to_copy)) { dev_dbg(dev, "Failed to copy data to user\n"); return -EFAULT; } *ppos += to_copy; smb_update_read_ptr(drvdata, to_copy); if (!sdb->data_size) smb_reset_buffer(drvdata); dev_dbg(dev, "%zu bytes copied\n", to_copy); 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); guard(spinlock)(&drvdata->spinlock); drvdata->reading = false; return 0; } static const struct file_operations smb_fops = { .owner = THIS_MODULE, .open = smb_open, .read = smb_read, .release = smb_release, .llseek = no_llseek, }; 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[] = { coresight_simple_reg32(read_pos, SMB_LB_RD_ADDR_REG), coresight_simple_reg32(write_pos, SMB_LB_WR_ADDR_REG), coresight_simple_reg32(buf_status, SMB_LB_INT_STS_REG), &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 void smb_enable_hw(struct smb_drv_data *drvdata) { writel(SMB_GLB_EN_HW_ENABLE, drvdata->base + SMB_GLB_EN_REG); } static void smb_disable_hw(struct smb_drv_data *drvdata) { writel(0x0, drvdata->base + SMB_GLB_EN_REG); } static void smb_enable_sysfs(struct coresight_device *csdev) { struct smb_drv_data *drvdata = dev_get_drvdata(csdev->dev.parent); if (drvdata->mode != CS_MODE_DISABLED) return; smb_enable_hw(drvdata); drvdata->mode = CS_MODE_SYSFS; } static int smb_enable_perf(struct coresight_device *csdev, void *data) { struct smb_drv_data *drvdata = dev_get_drvdata(csdev->dev.parent); struct perf_output_handle *handle = data; struct cs_buffers *buf = etm_perf_sink_config(handle); pid_t pid; if (!buf) return -EINVAL; /* Get a handle on the pid of the target process */ pid = buf->pid; /* Device is already in used by other session */ if (drvdata->pid != -1 && drvdata->pid != pid) return -EBUSY; if (drvdata->pid == -1) { smb_enable_hw(drvdata); drvdata->pid = pid; drvdata->mode = CS_MODE_PERF; } return 0; } static int smb_enable(struct coresight_device *csdev, enum cs_mode mode, void *data) { struct smb_drv_data *drvdata = dev_get_drvdata(csdev->dev.parent); int ret = 0; guard(spinlock)(&drvdata->spinlock); /* Do nothing, the trace data is reading by other interface now */ if (drvdata->reading) return -EBUSY; /* Do nothing, the SMB is already enabled as other mode */ if (drvdata->mode != CS_MODE_DISABLED && drvdata->mode != mode) return -EBUSY; switch (mode) { case CS_MODE_SYSFS: smb_enable_sysfs(csdev); break; case CS_MODE_PERF: ret = smb_enable_perf(csdev, data); break; default: ret = -EINVAL; } if (ret) return ret; atomic_inc(&csdev->refcnt); dev_dbg(&csdev->dev, "Ultrasoc SMB enabled\n"); return ret; } static int smb_disable(struct coresight_device *csdev) { struct smb_drv_data *drvdata = dev_get_drvdata(csdev->dev.parent); guard(spinlock)(&drvdata->spinlock); if (drvdata->reading) return -EBUSY; if (atomic_dec_return(&csdev->refcnt)) return -EBUSY; /* Complain if we (somehow) got out of sync */ WARN_ON_ONCE(drvdata->mode == CS_MODE_DISABLED); smb_disable_hw(drvdata); /* Dissociate from the target process. */ drvdata->pid = -1; drvdata->mode = CS_MODE_DISABLED; 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 head) { struct smb_data_buffer *sdb = &drvdata->sdb; char **dst_pages = (char **)buf->data_pages; unsigned long to_copy; long pg_idx, pg_offset; pg_idx = head >> PAGE_SHIFT; pg_offset = head & (PAGE_SIZE - 1); while (sdb->data_size) { unsigned long pg_space = PAGE_SIZE - pg_offset; to_copy = min(sdb->data_size, pg_space); /* Copy parts of trace data when read pointer wrap around */ if (sdb->buf_rdptr + to_copy > sdb->buf_size) to_copy = sdb->buf_size - sdb->buf_rdptr; memcpy(dst_pages[pg_idx] + pg_offset, sdb->buf_base + sdb->buf_rdptr, to_copy); pg_offset += to_copy; if (pg_offset >= PAGE_SIZE) { pg_offset = 0; pg_idx++; pg_idx %= buf->nr_pages; } smb_update_read_ptr(drvdata, to_copy); } smb_reset_buffer(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; bool lost = false; if (!buf) return 0; guard(spinlock)(&drvdata->spinlock); /* Don't do anything if another tracer is using this sink. */ if (atomic_read(&csdev->refcnt) != 1) return 0; smb_disable_hw(drvdata); smb_update_data_size(drvdata); /* * 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 (sdb->data_size > handle->size) { smb_update_read_ptr(drvdata, sdb->data_size - handle->size); lost = true; } data_size = sdb->data_size; smb_sync_perf_buffer(drvdata, buf, handle->head); if (!buf->snapshot && lost) perf_aux_output_flag(handle, PERF_AUX_FLAG_TRUNCATED); 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 *base; res = platform_get_resource(pdev, IORESOURCE_MEM, SMB_BUF_ADDR_RES); if (!res) { dev_err(&pdev->dev, "SMB device failed to get resource\n"); return -EINVAL; } sdb->buf_rdptr = 0; sdb->buf_hw_base = FIELD_GET(SMB_BUF_ADDR_LO_MSK, res->start); sdb->buf_size = resource_size(res); if (sdb->buf_size == 0) return -EINVAL; /* * This is a chunk of memory, use classic mapping with better * performance. */ base = devm_memremap(&pdev->dev, sdb->buf_hw_base, sdb->buf_size, MEMREMAP_WB); if (IS_ERR(base)) return PTR_ERR(base); sdb->buf_base = base; return 0; } static void smb_init_hw(struct smb_drv_data *drvdata) { smb_disable_hw(drvdata); writel(SMB_LB_CFG_LO_DEFAULT, drvdata->base + SMB_LB_CFG_LO_REG); writel(SMB_LB_CFG_HI_DEFAULT, drvdata->base + SMB_LB_CFG_HI_REG); writel(SMB_GLB_CFG_DEFAULT, drvdata->base + SMB_GLB_CFG_REG); writel(SMB_GLB_INT_CFG, drvdata->base + SMB_GLB_INT_REG); writel(SMB_LB_INT_CTRL_CFG, drvdata->base + SMB_LB_INT_CTRL_REG); } 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); if (!desc.name) { dev_err(&pdev->dev, "Failed to alloc coresight device name"); return -ENOMEM; } desc.access = CSDEV_ACCESS_IOMEM(drvdata->base); 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"); return -ENODEV; } ACPI_FREE(obj); return 0; } static int smb_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct smb_drv_data *drvdata; int ret; drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL); if (!drvdata) return -ENOMEM; drvdata->base = devm_platform_ioremap_resource(pdev, SMB_REG_ADDR_RES); if (IS_ERR(drvdata->base)) { dev_err(dev, "Failed to ioremap resource\n"); return PTR_ERR(drvdata->base); } smb_init_hw(drvdata); ret = smb_init_data_buffer(pdev, &drvdata->sdb); if (ret) { dev_err(dev, "Failed to init buffer, ret = %d\n", ret); return ret; } ret = smb_config_inport(dev, true); if (ret) return ret; smb_reset_buffer(drvdata); platform_set_drvdata(pdev, drvdata); spin_lock_init(&drvdata->spinlock); drvdata->pid = -1; ret = smb_register_sink(pdev, drvdata); if (ret) { smb_config_inport(&pdev->dev, false); dev_err(dev, "Failed to register SMB sink\n"); return ret; } return 0; } static void smb_remove(struct platform_device *pdev) { struct smb_drv_data *drvdata = platform_get_drvdata(pdev); smb_unregister_sink(drvdata); smb_config_inport(&pdev->dev, false); } #ifdef CONFIG_ACPI static const struct acpi_device_id ultrasoc_smb_acpi_match[] = { {"HISI03A1", 0}, {} }; MODULE_DEVICE_TABLE(acpi, ultrasoc_smb_acpi_match); #endif 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_new = smb_remove, }; module_platform_driver(smb_driver); MODULE_DESCRIPTION("UltraSoc SMB CoreSight driver"); MODULE_LICENSE("Dual MIT/GPL"); MODULE_AUTHOR("Jonathan Zhou "); MODULE_AUTHOR("Qi Liu ");