From fdfc0d8a06b56c3ca8fc3d7d271b3c8e99e6d55c Mon Sep 17 00:00:00 2001 From: Pratik Patel Date: Mon, 3 Nov 2014 11:07:38 -0700 Subject: coresight-etb: add CoreSight ETB driver This driver manages CoreSight ETB (Embedded Trace Buffer) which acts as a circular buffer sink collecting generated trace data. Signed-off-by: Pratik Patel Signed-off-by: Mathieu Poirier Signed-off-by: Greg Kroah-Hartman diff --git a/arch/arm/Kconfig.debug b/arch/arm/Kconfig.debug index 4815efb..db67170 100644 --- a/arch/arm/Kconfig.debug +++ b/arch/arm/Kconfig.debug @@ -1368,5 +1368,13 @@ config CORESIGHT_SINK_TPIU for bridging the gap between the on-chip coresight components and a trace port collection engine, typically connected to an external host for use case capturing more traces than the on-board coresight memory can handle. + +config CORESIGHT_SINK_ETBV10 + bool "Coresight ETBv1.0 driver" + depends on CORESIGHT_LINKS_AND_SINKS + help + This enables support for the Embedded Trace Buffer version 1.0 driver + that complies with the generic implementation of the component without + special enhancement or added features. endif endmenu diff --git a/drivers/coresight/Makefile b/drivers/coresight/Makefile index 41ab769..4c43dad 100644 --- a/drivers/coresight/Makefile +++ b/drivers/coresight/Makefile @@ -5,3 +5,4 @@ obj-$(CONFIG_CORESIGHT) += coresight.o obj-$(CONFIG_OF) += of_coresight.o obj-$(CONFIG_CORESIGHT_LINK_AND_SINK_TMC) += coresight-tmc.o obj-$(CONFIG_CORESIGHT_SINK_TPIU) += coresight-tpiu.o +obj-$(CONFIG_CORESIGHT_SINK_ETBV10) += coresight-etb10.o diff --git a/drivers/coresight/coresight-etb10.c b/drivers/coresight/coresight-etb10.c new file mode 100644 index 0000000..c922d4a --- /dev/null +++ b/drivers/coresight/coresight-etb10.c @@ -0,0 +1,537 @@ +/* Copyright (c) 2011-2012, The Linux Foundation. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 and + * only version 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#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. + * @csdev: component vitals needed by the framework. + * @miscdev: specifics to handle "/dev/xyz.etb" entry. + * @clk: the clock this component is associated to. + * @spinlock: only one at a time pls. + * @in_use: synchronise user space access to etb buffer. + * @buf: area of memory where ETB buffer content gets sent. + * @buffer_depth: size of @buf. + * @enable: this ETB is being used. + * @trigger_cntr: amount of words to store after a trigger. + */ +struct etb_drvdata { + void __iomem *base; + struct device *dev; + struct coresight_device *csdev; + struct miscdevice miscdev; + struct clk *clk; + spinlock_t spinlock; + atomic_t in_use; + u8 *buf; + u32 buffer_depth; + bool enable; + u32 trigger_cntr; +}; + +static unsigned int etb_get_buffer_depth(struct etb_drvdata *drvdata) +{ + int ret; + u32 depth = 0; + + ret = clk_prepare_enable(drvdata->clk); + if (ret) + return ret; + + /* RO registers don't need locking */ + depth = readl_relaxed(drvdata->base + ETB_RAM_DEPTH_REG); + + clk_disable_unprepare(drvdata->clk); + 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) +{ + struct etb_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); + int ret; + unsigned long flags; + + ret = clk_prepare_enable(drvdata->clk); + if (ret) + return ret; + + spin_lock_irqsave(&drvdata->spinlock, flags); + etb_enable_hw(drvdata); + drvdata->enable = true; + spin_unlock_irqrestore(&drvdata->spinlock, flags); + + 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 observed when probing at offset %#x\n", + ETB_FFCR); + } + + /* 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 observed when probing at offset %#x\n", + ETB_FFCR); + } + + CS_LOCK(drvdata->base); +} + +static void etb_dump_hw(struct etb_drvdata *drvdata) +{ + 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); + + 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); + *buf_ptr++ = read_data >> 0; + *buf_ptr++ = read_data >> 8; + *buf_ptr++ = read_data >> 16; + *buf_ptr++ = read_data >> 24; + } + + 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); + drvdata->enable = false; + spin_unlock_irqrestore(&drvdata->spinlock, flags); + + clk_disable_unprepare(drvdata->clk); + + dev_info(drvdata->dev, "ETB disabled\n"); +} + +static const struct coresight_ops_sink etb_sink_ops = { + .enable = etb_enable, + .disable = etb_disable, +}; + +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 (drvdata->enable) { + 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 (atomic_cmpxchg(&drvdata->in_use, 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: %d 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); + atomic_set(&drvdata->in_use, 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, +}; + +static ssize_t status_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + int ret; + unsigned long flags; + u32 etb_rdr, etb_sr, etb_rrp, etb_rwp; + u32 etb_trg, etb_cr, etb_ffsr, etb_ffcr; + struct etb_drvdata *drvdata = dev_get_drvdata(dev->parent); + + ret = clk_prepare_enable(drvdata->clk); + if (ret) + goto out; + + spin_lock_irqsave(&drvdata->spinlock, flags); + CS_UNLOCK(drvdata->base); + + etb_rdr = readl_relaxed(drvdata->base + ETB_RAM_DEPTH_REG); + etb_sr = readl_relaxed(drvdata->base + ETB_STATUS_REG); + etb_rrp = readl_relaxed(drvdata->base + ETB_RAM_READ_POINTER); + etb_rwp = readl_relaxed(drvdata->base + ETB_RAM_WRITE_POINTER); + etb_trg = readl_relaxed(drvdata->base + ETB_TRG); + etb_cr = readl_relaxed(drvdata->base + ETB_CTL_REG); + etb_ffsr = readl_relaxed(drvdata->base + ETB_FFSR); + etb_ffcr = readl_relaxed(drvdata->base + ETB_FFCR); + + CS_LOCK(drvdata->base); + spin_unlock_irqrestore(&drvdata->spinlock, flags); + + clk_disable_unprepare(drvdata->clk); + + return sprintf(buf, + "Depth:\t\t0x%x\n" + "Status:\t\t0x%x\n" + "RAM read ptr:\t0x%x\n" + "RAM wrt ptr:\t0x%x\n" + "Trigger cnt:\t0x%x\n" + "Control:\t0x%x\n" + "Flush status:\t0x%x\n" + "Flush ctrl:\t0x%x\n", + etb_rdr, etb_sr, etb_rrp, etb_rwp, + etb_trg, etb_cr, etb_ffsr, etb_ffcr); +out: + return -EINVAL; +} +static DEVICE_ATTR_RO(status); + +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, + &dev_attr_status.attr, + NULL, +}; +ATTRIBUTE_GROUPS(coresight_etb); + +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; + 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; + 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->clk = adev->pclk; + ret = clk_prepare_enable(drvdata->clk); + if (ret) + return ret; + + drvdata->buffer_depth = etb_get_buffer_depth(drvdata); + clk_disable_unprepare(drvdata->clk); + + if (drvdata->buffer_depth < 0) + return -EINVAL; + + drvdata->buf = devm_kzalloc(dev, + drvdata->buffer_depth * 4, GFP_KERNEL); + if (!drvdata->buf) + return -ENOMEM; + + desc = devm_kzalloc(dev, sizeof(*desc), GFP_KERNEL); + if (!desc) + 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; + + dev_info(dev, "ETB initialized\n"); + return 0; + +err_misc_register: + coresight_unregister(drvdata->csdev); + return ret; +} + +static int etb_remove(struct amba_device *adev) +{ + struct etb_drvdata *drvdata = amba_get_drvdata(adev); + + misc_deregister(&drvdata->miscdev); + coresight_unregister(drvdata->csdev); + return 0; +} + +static struct amba_id etb_ids[] = { + { + .id = 0x0003b907, + .mask = 0x0003ffff, + }, + { 0, 0}, +}; + +static struct amba_driver etb_driver = { + .drv = { + .name = "coresight-etb10", + .owner = THIS_MODULE, + }, + .probe = etb_probe, + .remove = etb_remove, + .id_table = etb_ids, +}; + +static int __init etb_init(void) +{ + return amba_driver_register(&etb_driver); +} +module_init(etb_init); + +static void __exit etb_exit(void) +{ + amba_driver_unregister(&etb_driver); +} +module_exit(etb_exit); + +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("CoreSight Embedded Trace Buffer driver"); 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