diff options
Diffstat (limited to 'drivers/hwtracing/coresight/coresight-etb10.c')
| -rw-r--r-- | drivers/hwtracing/coresight/coresight-etb10.c | 758 |
1 files changed, 758 insertions, 0 deletions
diff --git a/drivers/hwtracing/coresight/coresight-etb10.c b/drivers/hwtracing/coresight/coresight-etb10.c new file mode 100644 index 000000000..6cf28b049 --- /dev/null +++ b/drivers/hwtracing/coresight/coresight-etb10.c @@ -0,0 +1,758 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2011-2012, The Linux Foundation. All rights reserved. + * + * Description: CoreSight Embedded Trace Buffer driver + */ + +#include <asm/local.h> +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/types.h> +#include <linux/device.h> +#include <linux/io.h> +#include <linux/err.h> +#include <linux/fs.h> +#include <linux/miscdevice.h> +#include <linux/uaccess.h> +#include <linux/slab.h> +#include <linux/spinlock.h> +#include <linux/pm_runtime.h> +#include <linux/seq_file.h> +#include <linux/coresight.h> +#include <linux/amba/bus.h> +#include <linux/clk.h> +#include <linux/circ_buf.h> +#include <linux/mm.h> +#include <linux/perf_event.h> + + +#include "coresight-priv.h" + +#define ETB_RAM_DEPTH_REG 0x004 +#define ETB_STATUS_REG 0x00c +#define ETB_RAM_READ_DATA_REG 0x010 +#define ETB_RAM_READ_POINTER 0x014 +#define ETB_RAM_WRITE_POINTER 0x018 +#define ETB_TRG 0x01c +#define ETB_CTL_REG 0x020 +#define ETB_RWD_REG 0x024 +#define ETB_FFSR 0x300 +#define ETB_FFCR 0x304 +#define ETB_ITMISCOP0 0xee0 +#define ETB_ITTRFLINACK 0xee4 +#define ETB_ITTRFLIN 0xee8 +#define ETB_ITATBDATA0 0xeeC +#define ETB_ITATBCTR2 0xef0 +#define ETB_ITATBCTR1 0xef4 +#define ETB_ITATBCTR0 0xef8 + +/* register description */ +/* STS - 0x00C */ +#define ETB_STATUS_RAM_FULL BIT(0) +/* CTL - 0x020 */ +#define ETB_CTL_CAPT_EN BIT(0) +/* FFCR - 0x304 */ +#define ETB_FFCR_EN_FTC BIT(0) +#define ETB_FFCR_FON_MAN BIT(6) +#define ETB_FFCR_STOP_FI BIT(12) +#define ETB_FFCR_STOP_TRIGGER BIT(13) + +#define ETB_FFCR_BIT 6 +#define ETB_FFSR_BIT 1 +#define ETB_FRAME_SIZE_WORDS 4 + +/** + * struct etb_drvdata - specifics associated to an ETB component + * @base: memory mapped base address for this component. + * @dev: the device entity associated to this component. + * @atclk: optional clock for the core parts of the ETB. + * @csdev: component vitals needed by the framework. + * @miscdev: specifics to handle "/dev/xyz.etb" entry. + * @spinlock: only one at a time pls. + * @reading: synchronise user space access to etb buffer. + * @mode: this ETB is being used. + * @buf: area of memory where ETB buffer content gets sent. + * @buffer_depth: size of @buf. + * @trigger_cntr: amount of words to store after a trigger. + */ +struct etb_drvdata { + void __iomem *base; + struct device *dev; + struct clk *atclk; + struct coresight_device *csdev; + struct miscdevice miscdev; + spinlock_t spinlock; + local_t reading; + local_t mode; + u8 *buf; + u32 buffer_depth; + u32 trigger_cntr; +}; + +static unsigned int etb_get_buffer_depth(struct etb_drvdata *drvdata) +{ + u32 depth = 0; + + pm_runtime_get_sync(drvdata->dev); + + /* RO registers don't need locking */ + depth = readl_relaxed(drvdata->base + ETB_RAM_DEPTH_REG); + + pm_runtime_put(drvdata->dev); + return depth; +} + +static void etb_enable_hw(struct etb_drvdata *drvdata) +{ + int i; + u32 depth; + + CS_UNLOCK(drvdata->base); + + depth = drvdata->buffer_depth; + /* reset write RAM pointer address */ + writel_relaxed(0x0, drvdata->base + ETB_RAM_WRITE_POINTER); + /* clear entire RAM buffer */ + for (i = 0; i < depth; i++) + writel_relaxed(0x0, drvdata->base + ETB_RWD_REG); + + /* reset write RAM pointer address */ + writel_relaxed(0x0, drvdata->base + ETB_RAM_WRITE_POINTER); + /* reset read RAM pointer address */ + writel_relaxed(0x0, drvdata->base + ETB_RAM_READ_POINTER); + + writel_relaxed(drvdata->trigger_cntr, drvdata->base + ETB_TRG); + writel_relaxed(ETB_FFCR_EN_FTC | ETB_FFCR_STOP_TRIGGER, + drvdata->base + ETB_FFCR); + /* ETB trace capture enable */ + writel_relaxed(ETB_CTL_CAPT_EN, drvdata->base + ETB_CTL_REG); + + CS_LOCK(drvdata->base); +} + +static int etb_enable(struct coresight_device *csdev, u32 mode) +{ + u32 val; + unsigned long flags; + struct etb_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); + + val = local_cmpxchg(&drvdata->mode, + CS_MODE_DISABLED, mode); + /* + * When accessing from Perf, a HW buffer can be handled + * by a single trace entity. In sysFS mode many tracers + * can be logging to the same HW buffer. + */ + if (val == CS_MODE_PERF) + return -EBUSY; + + /* Don't let perf disturb sysFS sessions */ + if (val == CS_MODE_SYSFS && mode == CS_MODE_PERF) + return -EBUSY; + + /* Nothing to do, the tracer is already enabled. */ + if (val == CS_MODE_SYSFS) + goto out; + + spin_lock_irqsave(&drvdata->spinlock, flags); + etb_enable_hw(drvdata); + spin_unlock_irqrestore(&drvdata->spinlock, flags); + +out: + dev_info(drvdata->dev, "ETB enabled\n"); + return 0; +} + +static void etb_disable_hw(struct etb_drvdata *drvdata) +{ + u32 ffcr; + + CS_UNLOCK(drvdata->base); + + ffcr = readl_relaxed(drvdata->base + ETB_FFCR); + /* stop formatter when a stop has completed */ + ffcr |= ETB_FFCR_STOP_FI; + writel_relaxed(ffcr, drvdata->base + ETB_FFCR); + /* manually generate a flush of the system */ + ffcr |= ETB_FFCR_FON_MAN; + writel_relaxed(ffcr, drvdata->base + ETB_FFCR); + + if (coresight_timeout(drvdata->base, ETB_FFCR, ETB_FFCR_BIT, 0)) { + dev_err(drvdata->dev, + "timeout while waiting for completion of Manual Flush\n"); + } + + /* disable trace capture */ + writel_relaxed(0x0, drvdata->base + ETB_CTL_REG); + + if (coresight_timeout(drvdata->base, ETB_FFSR, ETB_FFSR_BIT, 1)) { + dev_err(drvdata->dev, + "timeout while waiting for Formatter to Stop\n"); + } + + CS_LOCK(drvdata->base); +} + +static void etb_dump_hw(struct etb_drvdata *drvdata) +{ + bool lost = false; + int i; + u8 *buf_ptr; + u32 read_data, depth; + u32 read_ptr, write_ptr; + u32 frame_off, frame_endoff; + + CS_UNLOCK(drvdata->base); + + read_ptr = readl_relaxed(drvdata->base + ETB_RAM_READ_POINTER); + write_ptr = readl_relaxed(drvdata->base + ETB_RAM_WRITE_POINTER); + + frame_off = write_ptr % ETB_FRAME_SIZE_WORDS; + frame_endoff = ETB_FRAME_SIZE_WORDS - frame_off; + if (frame_off) { + dev_err(drvdata->dev, + "write_ptr: %lu not aligned to formatter frame size\n", + (unsigned long)write_ptr); + dev_err(drvdata->dev, "frameoff: %lu, frame_endoff: %lu\n", + (unsigned long)frame_off, (unsigned long)frame_endoff); + write_ptr += frame_endoff; + } + + if ((readl_relaxed(drvdata->base + ETB_STATUS_REG) + & ETB_STATUS_RAM_FULL) == 0) { + writel_relaxed(0x0, drvdata->base + ETB_RAM_READ_POINTER); + } else { + writel_relaxed(write_ptr, drvdata->base + ETB_RAM_READ_POINTER); + lost = true; + } + + depth = drvdata->buffer_depth; + buf_ptr = drvdata->buf; + for (i = 0; i < depth; i++) { + read_data = readl_relaxed(drvdata->base + + ETB_RAM_READ_DATA_REG); + *(u32 *)buf_ptr = read_data; + buf_ptr += 4; + } + + if (lost) + coresight_insert_barrier_packet(drvdata->buf); + + if (frame_off) { + buf_ptr -= (frame_endoff * 4); + for (i = 0; i < frame_endoff; i++) { + *buf_ptr++ = 0x0; + *buf_ptr++ = 0x0; + *buf_ptr++ = 0x0; + *buf_ptr++ = 0x0; + } + } + + writel_relaxed(read_ptr, drvdata->base + ETB_RAM_READ_POINTER); + + CS_LOCK(drvdata->base); +} + +static void etb_disable(struct coresight_device *csdev) +{ + struct etb_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); + unsigned long flags; + + spin_lock_irqsave(&drvdata->spinlock, flags); + etb_disable_hw(drvdata); + etb_dump_hw(drvdata); + spin_unlock_irqrestore(&drvdata->spinlock, flags); + + local_set(&drvdata->mode, CS_MODE_DISABLED); + + dev_info(drvdata->dev, "ETB disabled\n"); +} + +static void *etb_alloc_buffer(struct coresight_device *csdev, int cpu, + void **pages, int nr_pages, bool overwrite) +{ + int node; + struct cs_buffers *buf; + + node = (cpu == -1) ? NUMA_NO_NODE : cpu_to_node(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; + + return buf; +} + +static void etb_free_buffer(void *config) +{ + struct cs_buffers *buf = config; + + kfree(buf); +} + +static int etb_set_buffer(struct coresight_device *csdev, + struct perf_output_handle *handle, + void *sink_config) +{ + int ret = 0; + unsigned long head; + struct cs_buffers *buf = sink_config; + + /* 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 */ + buf->cur = head / PAGE_SIZE; + + /* and offset within that page */ + buf->offset = head % PAGE_SIZE; + + local_set(&buf->data_size, 0); + + return ret; +} + +static unsigned long etb_reset_buffer(struct coresight_device *csdev, + struct perf_output_handle *handle, + void *sink_config) +{ + unsigned long size = 0; + struct cs_buffers *buf = sink_config; + + if (buf) { + /* + * In snapshot mode ->data_size holds the new address of the + * ring buffer's head. The size itself is the whole address + * range since we want the latest information. + */ + if (buf->snapshot) + handle->head = local_xchg(&buf->data_size, + buf->nr_pages << PAGE_SHIFT); + + /* + * Tell the tracer PMU how much we got in this run and if + * something went wrong along the way. Nobody else can use + * this cs_buffers instance until we are done. As such + * resetting parameters here and squaring off with the ring + * buffer API in the tracer PMU is fine. + */ + size = local_xchg(&buf->data_size, 0); + } + + return size; +} + +static void etb_update_buffer(struct coresight_device *csdev, + struct perf_output_handle *handle, + void *sink_config) +{ + bool lost = false; + int i, cur; + u8 *buf_ptr; + const u32 *barrier; + u32 read_ptr, write_ptr, capacity; + u32 status, read_data, to_read; + unsigned long offset; + struct cs_buffers *buf = sink_config; + struct etb_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); + + if (!buf) + return; + + capacity = drvdata->buffer_depth * ETB_FRAME_SIZE_WORDS; + + etb_disable_hw(drvdata); + CS_UNLOCK(drvdata->base); + + /* unit is in words, not bytes */ + read_ptr = readl_relaxed(drvdata->base + ETB_RAM_READ_POINTER); + write_ptr = readl_relaxed(drvdata->base + ETB_RAM_WRITE_POINTER); + + /* + * Entries should be aligned to the frame size. If they are not + * go back to the last alignment point to give decoding tools a + * chance to fix things. + */ + if (write_ptr % ETB_FRAME_SIZE_WORDS) { + dev_err(drvdata->dev, + "write_ptr: %lu not aligned to formatter frame size\n", + (unsigned long)write_ptr); + + write_ptr &= ~(ETB_FRAME_SIZE_WORDS - 1); + lost = true; + } + + /* + * Get a hold of the status register and see if a wrap around + * has occurred. If so adjust things accordingly. Otherwise + * start at the beginning and go until the write pointer has + * been reached. + */ + status = readl_relaxed(drvdata->base + ETB_STATUS_REG); + if (status & ETB_STATUS_RAM_FULL) { + lost = true; + to_read = capacity; + read_ptr = write_ptr; + } else { + to_read = CIRC_CNT(write_ptr, read_ptr, drvdata->buffer_depth); + to_read *= ETB_FRAME_SIZE_WORDS; + } + + /* + * Make sure we don't overwrite data that hasn't been consumed yet. + * It is entirely possible that the HW buffer has more data than the + * ring buffer can currently handle. If so adjust the start address + * to take only the last traces. + * + * In snapshot mode we are looking to get the latest traces only and as + * such, we don't care about not overwriting data that hasn't been + * processed by user space. + */ + if (!buf->snapshot && to_read > handle->size) { + u32 mask = ~(ETB_FRAME_SIZE_WORDS - 1); + + /* The new read pointer must be frame size aligned */ + to_read = handle->size & mask; + /* + * Move the RAM read pointer up, keeping in mind that + * everything is in frame size units. + */ + read_ptr = (write_ptr + drvdata->buffer_depth) - + to_read / ETB_FRAME_SIZE_WORDS; + /* Wrap around if need be*/ + if (read_ptr > (drvdata->buffer_depth - 1)) + read_ptr -= drvdata->buffer_depth; + /* let the decoder know we've skipped ahead */ + lost = true; + } + + if (lost) + perf_aux_output_flag(handle, PERF_AUX_FLAG_TRUNCATED); + + /* finally tell HW where we want to start reading from */ + writel_relaxed(read_ptr, drvdata->base + ETB_RAM_READ_POINTER); + + cur = buf->cur; + offset = buf->offset; + barrier = barrier_pkt; + + for (i = 0; i < to_read; i += 4) { + buf_ptr = buf->data_pages[cur] + offset; + read_data = readl_relaxed(drvdata->base + + ETB_RAM_READ_DATA_REG); + if (lost && i < CORESIGHT_BARRIER_PKT_SIZE) { + read_data = *barrier; + barrier++; + } + + *(u32 *)buf_ptr = read_data; + buf_ptr += 4; + + offset += 4; + if (offset >= PAGE_SIZE) { + offset = 0; + cur++; + /* wrap around at the end of the buffer */ + cur &= buf->nr_pages - 1; + } + } + + /* reset ETB buffer for next run */ + writel_relaxed(0x0, drvdata->base + ETB_RAM_READ_POINTER); + writel_relaxed(0x0, drvdata->base + ETB_RAM_WRITE_POINTER); + + /* + * In snapshot mode all we have to do is communicate to + * perf_aux_output_end() the address of the current head. In full + * trace mode the same function expects a size to move rb->aux_head + * forward. + */ + if (buf->snapshot) + local_set(&buf->data_size, (cur * PAGE_SIZE) + offset); + else + local_add(to_read, &buf->data_size); + + etb_enable_hw(drvdata); + CS_LOCK(drvdata->base); +} + +static const struct coresight_ops_sink etb_sink_ops = { + .enable = etb_enable, + .disable = etb_disable, + .alloc_buffer = etb_alloc_buffer, + .free_buffer = etb_free_buffer, + .set_buffer = etb_set_buffer, + .reset_buffer = etb_reset_buffer, + .update_buffer = etb_update_buffer, +}; + +static const struct coresight_ops etb_cs_ops = { + .sink_ops = &etb_sink_ops, +}; + +static void etb_dump(struct etb_drvdata *drvdata) +{ + unsigned long flags; + + spin_lock_irqsave(&drvdata->spinlock, flags); + if (local_read(&drvdata->mode) == CS_MODE_SYSFS) { + etb_disable_hw(drvdata); + etb_dump_hw(drvdata); + etb_enable_hw(drvdata); + } + spin_unlock_irqrestore(&drvdata->spinlock, flags); + + dev_info(drvdata->dev, "ETB dumped\n"); +} + +static int etb_open(struct inode *inode, struct file *file) +{ + struct etb_drvdata *drvdata = container_of(file->private_data, + struct etb_drvdata, miscdev); + + if (local_cmpxchg(&drvdata->reading, 0, 1)) + return -EBUSY; + + dev_dbg(drvdata->dev, "%s: successfully opened\n", __func__); + return 0; +} + +static ssize_t etb_read(struct file *file, char __user *data, + size_t len, loff_t *ppos) +{ + u32 depth; + struct etb_drvdata *drvdata = container_of(file->private_data, + struct etb_drvdata, miscdev); + + etb_dump(drvdata); + + depth = drvdata->buffer_depth; + if (*ppos + len > depth * 4) + len = depth * 4 - *ppos; + + if (copy_to_user(data, drvdata->buf + *ppos, len)) { + dev_dbg(drvdata->dev, "%s: copy_to_user failed\n", __func__); + return -EFAULT; + } + + *ppos += len; + + dev_dbg(drvdata->dev, "%s: %zu bytes copied, %d bytes left\n", + __func__, len, (int)(depth * 4 - *ppos)); + return len; +} + +static int etb_release(struct inode *inode, struct file *file) +{ + struct etb_drvdata *drvdata = container_of(file->private_data, + struct etb_drvdata, miscdev); + local_set(&drvdata->reading, 0); + + dev_dbg(drvdata->dev, "%s: released\n", __func__); + return 0; +} + +static const struct file_operations etb_fops = { + .owner = THIS_MODULE, + .open = etb_open, + .read = etb_read, + .release = etb_release, + .llseek = no_llseek, +}; + +#define coresight_etb10_reg(name, offset) \ + coresight_simple_reg32(struct etb_drvdata, name, offset) + +coresight_etb10_reg(rdp, ETB_RAM_DEPTH_REG); +coresight_etb10_reg(sts, ETB_STATUS_REG); +coresight_etb10_reg(rrp, ETB_RAM_READ_POINTER); +coresight_etb10_reg(rwp, ETB_RAM_WRITE_POINTER); +coresight_etb10_reg(trg, ETB_TRG); +coresight_etb10_reg(ctl, ETB_CTL_REG); +coresight_etb10_reg(ffsr, ETB_FFSR); +coresight_etb10_reg(ffcr, ETB_FFCR); + +static struct attribute *coresight_etb_mgmt_attrs[] = { + &dev_attr_rdp.attr, + &dev_attr_sts.attr, + &dev_attr_rrp.attr, + &dev_attr_rwp.attr, + &dev_attr_trg.attr, + &dev_attr_ctl.attr, + &dev_attr_ffsr.attr, + &dev_attr_ffcr.attr, + NULL, +}; + +static ssize_t trigger_cntr_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct etb_drvdata *drvdata = dev_get_drvdata(dev->parent); + unsigned long val = drvdata->trigger_cntr; + + return sprintf(buf, "%#lx\n", val); +} + +static ssize_t trigger_cntr_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t size) +{ + int ret; + unsigned long val; + struct etb_drvdata *drvdata = dev_get_drvdata(dev->parent); + + ret = kstrtoul(buf, 16, &val); + if (ret) + return ret; + + drvdata->trigger_cntr = val; + return size; +} +static DEVICE_ATTR_RW(trigger_cntr); + +static struct attribute *coresight_etb_attrs[] = { + &dev_attr_trigger_cntr.attr, + NULL, +}; + +static const struct attribute_group coresight_etb_group = { + .attrs = coresight_etb_attrs, +}; + +static const struct attribute_group coresight_etb_mgmt_group = { + .attrs = coresight_etb_mgmt_attrs, + .name = "mgmt", +}; + +const struct attribute_group *coresight_etb_groups[] = { + &coresight_etb_group, + &coresight_etb_mgmt_group, + NULL, +}; + +static int etb_probe(struct amba_device *adev, const struct amba_id *id) +{ + int ret; + void __iomem *base; + struct device *dev = &adev->dev; + struct coresight_platform_data *pdata = NULL; + struct etb_drvdata *drvdata; + struct resource *res = &adev->res; + struct coresight_desc desc = { 0 }; + struct device_node *np = adev->dev.of_node; + + if (np) { + pdata = of_get_coresight_platform_data(dev, np); + if (IS_ERR(pdata)) + return PTR_ERR(pdata); + adev->dev.platform_data = pdata; + } + + drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL); + if (!drvdata) + return -ENOMEM; + + drvdata->dev = &adev->dev; + drvdata->atclk = devm_clk_get(&adev->dev, "atclk"); /* optional */ + if (!IS_ERR(drvdata->atclk)) { + ret = clk_prepare_enable(drvdata->atclk); + if (ret) + return ret; + } + dev_set_drvdata(dev, drvdata); + + /* validity for the resource is already checked by the AMBA core */ + base = devm_ioremap_resource(dev, res); + if (IS_ERR(base)) + return PTR_ERR(base); + + drvdata->base = base; + + spin_lock_init(&drvdata->spinlock); + + drvdata->buffer_depth = etb_get_buffer_depth(drvdata); + pm_runtime_put(&adev->dev); + + if (drvdata->buffer_depth & 0x80000000) + return -EINVAL; + + drvdata->buf = devm_kcalloc(dev, + drvdata->buffer_depth, 4, GFP_KERNEL); + if (!drvdata->buf) + return -ENOMEM; + + desc.type = CORESIGHT_DEV_TYPE_SINK; + desc.subtype.sink_subtype = CORESIGHT_DEV_SUBTYPE_SINK_BUFFER; + desc.ops = &etb_cs_ops; + desc.pdata = pdata; + desc.dev = dev; + desc.groups = coresight_etb_groups; + drvdata->csdev = coresight_register(&desc); + if (IS_ERR(drvdata->csdev)) + return PTR_ERR(drvdata->csdev); + + drvdata->miscdev.name = pdata->name; + drvdata->miscdev.minor = MISC_DYNAMIC_MINOR; + drvdata->miscdev.fops = &etb_fops; + ret = misc_register(&drvdata->miscdev); + if (ret) + goto err_misc_register; + + return 0; + +err_misc_register: + coresight_unregister(drvdata->csdev); + return ret; +} + +#ifdef CONFIG_PM +static int etb_runtime_suspend(struct device *dev) +{ + struct etb_drvdata *drvdata = dev_get_drvdata(dev); + + if (drvdata && !IS_ERR(drvdata->atclk)) + clk_disable_unprepare(drvdata->atclk); + + return 0; +} + +static int etb_runtime_resume(struct device *dev) +{ + struct etb_drvdata *drvdata = dev_get_drvdata(dev); + + if (drvdata && !IS_ERR(drvdata->atclk)) + clk_prepare_enable(drvdata->atclk); + + return 0; +} +#endif + +static const struct dev_pm_ops etb_dev_pm_ops = { + SET_RUNTIME_PM_OPS(etb_runtime_suspend, etb_runtime_resume, NULL) +}; + +static const struct amba_id etb_ids[] = { + { + .id = 0x000bb907, + .mask = 0x000fffff, + }, + { 0, 0}, +}; + +static struct amba_driver etb_driver = { + .drv = { + .name = "coresight-etb10", + .owner = THIS_MODULE, + .pm = &etb_dev_pm_ops, + .suppress_bind_attrs = true, + + }, + .probe = etb_probe, + .id_table = etb_ids, +}; +builtin_amba_driver(etb_driver); |