[deliverable/linux.git] / drivers / hwtracing / coresight / coresight-etb10.c

/* 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 <linux/kernel.h>
#include <linux/module.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 "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.
 * @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 clk		*atclk;
	struct coresight_device	*csdev;
	struct miscdevice	miscdev;
	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)
{
	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)
{
	struct etb_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
	unsigned long flags;

	pm_runtime_get_sync(drvdata->dev);

	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);

	pm_runtime_put(drvdata->dev);

	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: %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);
	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)
{
	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);

	pm_runtime_get_sync(drvdata->dev);
	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);

	pm_runtime_put(drvdata->dev);

	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);

	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;
	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_kzalloc(dev,
				    drvdata->buffer_depth * 4, GFP_KERNEL);
	if (!drvdata->buf) {
		dev_err(dev, "Failed to allocate %u bytes for buffer data\n",
			drvdata->buffer_depth * 4);
		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;
}

#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 struct amba_id etb_ids[] = {
	{
		.id	= 0x0003b907,
		.mask	= 0x0003ffff,
	},
	{ 0, 0},
};

static struct amba_driver etb_driver = {
	.drv = {
		.name	= "coresight-etb10",
		.owner	= THIS_MODULE,
		.pm	= &etb_dev_pm_ops,

	},
	.probe		= etb_probe,
	.remove		= etb_remove,
	.id_table	= etb_ids,
};

module_amba_driver(etb_driver);

MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("CoreSight Embedded Trace Buffer driver");
Commit	Line	Data
fdfc0d8a PP	1	/* Copyright (c) 2011-2012, The Linux Foundation. All rights reserved.
	2	*
	3	* This program is free software; you can redistribute it and/or modify
	4	* it under the terms of the GNU General Public License version 2 and
	5	* only version 2 as published by the Free Software Foundation.
	6	*
	7	* This program is distributed in the hope that it will be useful,
	8	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	9	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	10	* GNU General Public License for more details.
	11	*/
	12
	13	#include <linux/kernel.h>
	14	#include <linux/module.h>
	15	#include <linux/init.h>
	16	#include <linux/types.h>
	17	#include <linux/device.h>
	18	#include <linux/io.h>
	19	#include <linux/err.h>
	20	#include <linux/fs.h>
	21	#include <linux/miscdevice.h>
	22	#include <linux/uaccess.h>
	23	#include <linux/slab.h>
	24	#include <linux/spinlock.h>
1b19f59d	25	#include <linux/pm_runtime.h>
fdfc0d8a PP	26	#include <linux/seq_file.h>
	27	#include <linux/coresight.h>
	28	#include <linux/amba/bus.h>
267b2c23	29	#include <linux/clk.h>
fdfc0d8a PP	30
	31	#include "coresight-priv.h"
	32
	33	#define ETB_RAM_DEPTH_REG 0x004
	34	#define ETB_STATUS_REG 0x00c
	35	#define ETB_RAM_READ_DATA_REG 0x010
	36	#define ETB_RAM_READ_POINTER 0x014
	37	#define ETB_RAM_WRITE_POINTER 0x018
	38	#define ETB_TRG 0x01c
	39	#define ETB_CTL_REG 0x020
	40	#define ETB_RWD_REG 0x024
	41	#define ETB_FFSR 0x300
	42	#define ETB_FFCR 0x304
	43	#define ETB_ITMISCOP0 0xee0
	44	#define ETB_ITTRFLINACK 0xee4
	45	#define ETB_ITTRFLIN 0xee8
	46	#define ETB_ITATBDATA0 0xeeC
	47	#define ETB_ITATBCTR2 0xef0
	48	#define ETB_ITATBCTR1 0xef4
	49	#define ETB_ITATBCTR0 0xef8
	50
	51	/* register description */
	52	/* STS - 0x00C */
	53	#define ETB_STATUS_RAM_FULL BIT(0)
	54	/* CTL - 0x020 */
	55	#define ETB_CTL_CAPT_EN BIT(0)
	56	/* FFCR - 0x304 */
	57	#define ETB_FFCR_EN_FTC BIT(0)
	58	#define ETB_FFCR_FON_MAN BIT(6)
	59	#define ETB_FFCR_STOP_FI BIT(12)
	60	#define ETB_FFCR_STOP_TRIGGER BIT(13)
	61
	62	#define ETB_FFCR_BIT 6
	63	#define ETB_FFSR_BIT 1
	64	#define ETB_FRAME_SIZE_WORDS 4
	65
	66	/**
	67	* struct etb_drvdata - specifics associated to an ETB component
	68	* @base: memory mapped base address for this component.
	69	* @dev: the device entity associated to this component.
267b2c23	70	* @atclk: optional clock for the core parts of the ETB.
fdfc0d8a PP	71	* @csdev: component vitals needed by the framework.
fdfc0d8a PP	72	* @miscdev: specifics to handle "/dev/xyz.etb" entry.
fdfc0d8a PP	73	* @spinlock: only one at a time pls.
	74	* @in_use: synchronise user space access to etb buffer.
	75	* @buf: area of memory where ETB buffer content gets sent.
	76	* @buffer_depth: size of @buf.
	77	* @enable: this ETB is being used.
	78	* @trigger_cntr: amount of words to store after a trigger.
	79	*/
	80	struct etb_drvdata {
	81	void __iomem *base;
	82	struct device *dev;
267b2c23	83	struct clk *atclk;
fdfc0d8a PP	84	struct coresight_device *csdev;
fdfc0d8a PP	85	struct miscdevice miscdev;
fdfc0d8a PP	86	spinlock_t spinlock;
	87	atomic_t in_use;
	88	u8 *buf;
	89	u32 buffer_depth;
	90	bool enable;
	91	u32 trigger_cntr;
	92	};
	93
	94	static unsigned int etb_get_buffer_depth(struct etb_drvdata *drvdata)
	95	{
fdfc0d8a PP	96	u32 depth = 0;
fdfc0d8a PP	97
1b19f59d	98	pm_runtime_get_sync(drvdata->dev);
fdfc0d8a PP	99
	100	/* RO registers don't need locking */
	101	depth = readl_relaxed(drvdata->base + ETB_RAM_DEPTH_REG);
	102
1b19f59d	103	pm_runtime_put(drvdata->dev);
fdfc0d8a PP	104	return depth;
	105	}
	106
	107	static void etb_enable_hw(struct etb_drvdata *drvdata)
	108	{
	109	int i;
	110	u32 depth;
	111
	112	CS_UNLOCK(drvdata->base);
	113
	114	depth = drvdata->buffer_depth;
	115	/* reset write RAM pointer address */
	116	writel_relaxed(0x0, drvdata->base + ETB_RAM_WRITE_POINTER);
	117	/* clear entire RAM buffer */
	118	for (i = 0; i < depth; i++)
	119	writel_relaxed(0x0, drvdata->base + ETB_RWD_REG);
	120
	121	/* reset write RAM pointer address */
	122	writel_relaxed(0x0, drvdata->base + ETB_RAM_WRITE_POINTER);
	123	/* reset read RAM pointer address */
	124	writel_relaxed(0x0, drvdata->base + ETB_RAM_READ_POINTER);
	125
	126	writel_relaxed(drvdata->trigger_cntr, drvdata->base + ETB_TRG);
	127	writel_relaxed(ETB_FFCR_EN_FTC \| ETB_FFCR_STOP_TRIGGER,
	128	drvdata->base + ETB_FFCR);
	129	/* ETB trace capture enable */
	130	writel_relaxed(ETB_CTL_CAPT_EN, drvdata->base + ETB_CTL_REG);
	131
	132	CS_LOCK(drvdata->base);
	133	}
	134
	135	static int etb_enable(struct coresight_device *csdev)
	136	{
	137	struct etb_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
fdfc0d8a PP	138	unsigned long flags;
fdfc0d8a PP	139
1b19f59d	140	pm_runtime_get_sync(drvdata->dev);
fdfc0d8a PP	141
	142	spin_lock_irqsave(&drvdata->spinlock, flags);
	143	etb_enable_hw(drvdata);
	144	drvdata->enable = true;
	145	spin_unlock_irqrestore(&drvdata->spinlock, flags);
	146
	147	dev_info(drvdata->dev, "ETB enabled\n");
	148	return 0;
	149	}
	150
	151	static void etb_disable_hw(struct etb_drvdata *drvdata)
	152	{
	153	u32 ffcr;
	154
	155	CS_UNLOCK(drvdata->base);
	156
	157	ffcr = readl_relaxed(drvdata->base + ETB_FFCR);
	158	/* stop formatter when a stop has completed */
	159	ffcr \|= ETB_FFCR_STOP_FI;
	160	writel_relaxed(ffcr, drvdata->base + ETB_FFCR);
	161	/* manually generate a flush of the system */
	162	ffcr \|= ETB_FFCR_FON_MAN;
	163	writel_relaxed(ffcr, drvdata->base + ETB_FFCR);
	164
	165	if (coresight_timeout(drvdata->base, ETB_FFCR, ETB_FFCR_BIT, 0)) {
	166	dev_err(drvdata->dev,
	167	"timeout observed when probing at offset %#x\n",
	168	ETB_FFCR);
	169	}
	170
	171	/* disable trace capture */
	172	writel_relaxed(0x0, drvdata->base + ETB_CTL_REG);
	173
	174	if (coresight_timeout(drvdata->base, ETB_FFSR, ETB_FFSR_BIT, 1)) {
	175	dev_err(drvdata->dev,
	176	"timeout observed when probing at offset %#x\n",
	177	ETB_FFCR);
	178	}
	179
	180	CS_LOCK(drvdata->base);
	181	}
	182
	183	static void etb_dump_hw(struct etb_drvdata *drvdata)
	184	{
	185	int i;
	186	u8 *buf_ptr;
	187	u32 read_data, depth;
	188	u32 read_ptr, write_ptr;
	189	u32 frame_off, frame_endoff;
	190
	191	CS_UNLOCK(drvdata->base);
	192
	193	read_ptr = readl_relaxed(drvdata->base + ETB_RAM_READ_POINTER);
	194	write_ptr = readl_relaxed(drvdata->base + ETB_RAM_WRITE_POINTER);
	195
	196	frame_off = write_ptr % ETB_FRAME_SIZE_WORDS;
	197	frame_endoff = ETB_FRAME_SIZE_WORDS - frame_off;
	198	if (frame_off) {
	199	dev_err(drvdata->dev,
	200	"write_ptr: %lu not aligned to formatter frame size\n",
	201	(unsigned long)write_ptr);
	202	dev_err(drvdata->dev, "frameoff: %lu, frame_endoff: %lu\n",
	203	(unsigned long)frame_off, (unsigned long)frame_endoff);
	204	write_ptr += frame_endoff;
205	}
206
207	if ((readl_relaxed(drvdata->base + ETB_STATUS_REG)
208	& ETB_STATUS_RAM_FULL) == 0)
209	writel_relaxed(0x0, drvdata->base + ETB_RAM_READ_POINTER);
210	else
211	writel_relaxed(write_ptr, drvdata->base + ETB_RAM_READ_POINTER);
212
213	depth = drvdata->buffer_depth;
214	buf_ptr = drvdata->buf;
215	for (i = 0; i < depth; i++) {
216	read_data = readl_relaxed(drvdata->base +
217	ETB_RAM_READ_DATA_REG);
218	*buf_ptr++ = read_data >> 0;
219	*buf_ptr++ = read_data >> 8;
220	*buf_ptr++ = read_data >> 16;
221	*buf_ptr++ = read_data >> 24;
222	}
223
224	if (frame_off) {
225	buf_ptr -= (frame_endoff * 4);
226	for (i = 0; i < frame_endoff; i++) {
227	*buf_ptr++ = 0x0;
228	*buf_ptr++ = 0x0;
229	*buf_ptr++ = 0x0;
230	*buf_ptr++ = 0x0;
231	}
232	}
233
234	writel_relaxed(read_ptr, drvdata->base + ETB_RAM_READ_POINTER);
235
236	CS_LOCK(drvdata->base);
237	}
238
239	static void etb_disable(struct coresight_device *csdev)
240	{
241	struct etb_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
242	unsigned long flags;
243
244	spin_lock_irqsave(&drvdata->spinlock, flags);
245	etb_disable_hw(drvdata);
246	etb_dump_hw(drvdata);
247	drvdata->enable = false;
248	spin_unlock_irqrestore(&drvdata->spinlock, flags);
249
1b19f59d	250	pm_runtime_put(drvdata->dev);
fdfc0d8a PP	251
	252	dev_info(drvdata->dev, "ETB disabled\n");
	253	}
	254
	255	static const struct coresight_ops_sink etb_sink_ops = {
	256	.enable = etb_enable,
	257	.disable = etb_disable,
	258	};
	259
	260	static const struct coresight_ops etb_cs_ops = {
	261	.sink_ops = &etb_sink_ops,
	262	};
	263
	264	static void etb_dump(struct etb_drvdata *drvdata)
	265	{
	266	unsigned long flags;
	267
	268	spin_lock_irqsave(&drvdata->spinlock, flags);
	269	if (drvdata->enable) {
	270	etb_disable_hw(drvdata);
	271	etb_dump_hw(drvdata);
	272	etb_enable_hw(drvdata);
	273	}
	274	spin_unlock_irqrestore(&drvdata->spinlock, flags);
	275
	276	dev_info(drvdata->dev, "ETB dumped\n");
	277	}
	278
	279	static int etb_open(struct inode inode, struct file file)
	280	{
	281	struct etb_drvdata *drvdata = container_of(file->private_data,
	282	struct etb_drvdata, miscdev);
	283
	284	if (atomic_cmpxchg(&drvdata->in_use, 0, 1))
	285	return -EBUSY;
	286
	287	dev_dbg(drvdata->dev, "%s: successfully opened\n", __func__);
	288	return 0;
	289	}
	290
	291	static ssize_t etb_read(struct file file, char __user data,
	292	size_t len, loff_t *ppos)
	293	{
	294	u32 depth;
	295	struct etb_drvdata *drvdata = container_of(file->private_data,
	296	struct etb_drvdata, miscdev);
	297
	298	etb_dump(drvdata);
	299
	300	depth = drvdata->buffer_depth;
	301	if (ppos + len > depth 4)
	302	len = depth * 4 - *ppos;
	303
	304	if (copy_to_user(data, drvdata->buf + *ppos, len)) {
	305	dev_dbg(drvdata->dev, "%s: copy_to_user failed\n", __func__);
	306	return -EFAULT;
	307	}
	308
	309	*ppos += len;
	310
72f641fe MP	311	dev_dbg(drvdata->dev, "%s: %zu bytes copied, %d bytes left\n",
72f641fe MP	312	__func__, len, (int)(depth * 4 - *ppos));
fdfc0d8a PP	313	return len;
	314	}
	315
	316	static int etb_release(struct inode inode, struct file file)
	317	{
	318	struct etb_drvdata *drvdata = container_of(file->private_data,
	319	struct etb_drvdata, miscdev);
	320	atomic_set(&drvdata->in_use, 0);
	321
	322	dev_dbg(drvdata->dev, "%s: released\n", __func__);
	323	return 0;
	324	}
	325
	326	static const struct file_operations etb_fops = {
	327	.owner = THIS_MODULE,
	328	.open = etb_open,
	329	.read = etb_read,
	330	.release = etb_release,
	331	.llseek = no_llseek,
	332	};
	333
	334	static ssize_t status_show(struct device *dev,
	335	struct device_attribute attr, char buf)
	336	{
fdfc0d8a PP	337	unsigned long flags;
	338	u32 etb_rdr, etb_sr, etb_rrp, etb_rwp;
	339	u32 etb_trg, etb_cr, etb_ffsr, etb_ffcr;
	340	struct etb_drvdata *drvdata = dev_get_drvdata(dev->parent);
	341
1b19f59d	342	pm_runtime_get_sync(drvdata->dev);
fdfc0d8a PP	343	spin_lock_irqsave(&drvdata->spinlock, flags);
	344	CS_UNLOCK(drvdata->base);
	345
	346	etb_rdr = readl_relaxed(drvdata->base + ETB_RAM_DEPTH_REG);
	347	etb_sr = readl_relaxed(drvdata->base + ETB_STATUS_REG);
	348	etb_rrp = readl_relaxed(drvdata->base + ETB_RAM_READ_POINTER);
	349	etb_rwp = readl_relaxed(drvdata->base + ETB_RAM_WRITE_POINTER);
	350	etb_trg = readl_relaxed(drvdata->base + ETB_TRG);
	351	etb_cr = readl_relaxed(drvdata->base + ETB_CTL_REG);
	352	etb_ffsr = readl_relaxed(drvdata->base + ETB_FFSR);
	353	etb_ffcr = readl_relaxed(drvdata->base + ETB_FFCR);
	354
	355	CS_LOCK(drvdata->base);
	356	spin_unlock_irqrestore(&drvdata->spinlock, flags);
	357
1b19f59d	358	pm_runtime_put(drvdata->dev);
fdfc0d8a PP	359
	360	return sprintf(buf,
	361	"Depth:\t\t0x%x\n"
	362	"Status:\t\t0x%x\n"
	363	"RAM read ptr:\t0x%x\n"
	364	"RAM wrt ptr:\t0x%x\n"
	365	"Trigger cnt:\t0x%x\n"
	366	"Control:\t0x%x\n"
	367	"Flush status:\t0x%x\n"
	368	"Flush ctrl:\t0x%x\n",
	369	etb_rdr, etb_sr, etb_rrp, etb_rwp,
	370	etb_trg, etb_cr, etb_ffsr, etb_ffcr);
1b19f59d	371
fdfc0d8a PP	372	return -EINVAL;
	373	}
	374	static DEVICE_ATTR_RO(status);
	375
	376	static ssize_t trigger_cntr_show(struct device *dev,
	377	struct device_attribute attr, char buf)
	378	{
	379	struct etb_drvdata *drvdata = dev_get_drvdata(dev->parent);
	380	unsigned long val = drvdata->trigger_cntr;
	381
	382	return sprintf(buf, "%#lx\n", val);
	383	}
	384
	385	static ssize_t trigger_cntr_store(struct device *dev,
	386	struct device_attribute *attr,
	387	const char *buf, size_t size)
	388	{
	389	int ret;
	390	unsigned long val;
	391	struct etb_drvdata *drvdata = dev_get_drvdata(dev->parent);
	392
	393	ret = kstrtoul(buf, 16, &val);
	394	if (ret)
	395	return ret;
	396
	397	drvdata->trigger_cntr = val;
	398	return size;
	399	}
	400	static DEVICE_ATTR_RW(trigger_cntr);
	401
	402	static struct attribute *coresight_etb_attrs[] = {
	403	&dev_attr_trigger_cntr.attr,
	404	&dev_attr_status.attr,
	405	NULL,
	406	};
	407	ATTRIBUTE_GROUPS(coresight_etb);
	408
	409	static int etb_probe(struct amba_device adev, const struct amba_id id)
	410	{
	411	int ret;
	412	void __iomem *base;
	413	struct device *dev = &adev->dev;
	414	struct coresight_platform_data *pdata = NULL;
	415	struct etb_drvdata *drvdata;
	416	struct resource *res = &adev->res;
	417	struct coresight_desc *desc;
	418	struct device_node *np = adev->dev.of_node;
	419
	420	if (np) {
	421	pdata = of_get_coresight_platform_data(dev, np);
	422	if (IS_ERR(pdata))
	423	return PTR_ERR(pdata);
	424	adev->dev.platform_data = pdata;
	425	}
	426
	427	drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
	428	if (!drvdata)
	429	return -ENOMEM;
	430
	431	drvdata->dev = &adev->dev;
267b2c23 LW	432	drvdata->atclk = devm_clk_get(&adev->dev, "atclk"); /* optional */
	433	if (!IS_ERR(drvdata->atclk)) {
	434	ret = clk_prepare_enable(drvdata->atclk);
	435	if (ret)
	436	return ret;
	437	}
fdfc0d8a PP	438	dev_set_drvdata(dev, drvdata);
	439
	440	/* validity for the resource is already checked by the AMBA core */
	441	base = devm_ioremap_resource(dev, res);
	442	if (IS_ERR(base))
	443	return PTR_ERR(base);
	444
	445	drvdata->base = base;
	446
	447	spin_lock_init(&drvdata->spinlock);
	448
d786a47d	449	drvdata->buffer_depth = etb_get_buffer_depth(drvdata);
1b19f59d	450	pm_runtime_put(&adev->dev);
fdfc0d8a	451
f5da7cb2	452	if (drvdata->buffer_depth & 0x80000000)
fdfc0d8a PP	453	return -EINVAL;
	454
	455	drvdata->buf = devm_kzalloc(dev,
	456	drvdata->buffer_depth * 4, GFP_KERNEL);
cc545449 MB	457	if (!drvdata->buf) {
	458	dev_err(dev, "Failed to allocate %u bytes for buffer data\n",
	459	drvdata->buffer_depth * 4);
fdfc0d8a	460	return -ENOMEM;
cc545449	461	}
fdfc0d8a PP	462
	463	desc = devm_kzalloc(dev, sizeof(*desc), GFP_KERNEL);
	464	if (!desc)
	465	return -ENOMEM;
	466
	467	desc->type = CORESIGHT_DEV_TYPE_SINK;
	468	desc->subtype.sink_subtype = CORESIGHT_DEV_SUBTYPE_SINK_BUFFER;
	469	desc->ops = &etb_cs_ops;
	470	desc->pdata = pdata;
	471	desc->dev = dev;
	472	desc->groups = coresight_etb_groups;
	473	drvdata->csdev = coresight_register(desc);
	474	if (IS_ERR(drvdata->csdev))
	475	return PTR_ERR(drvdata->csdev);
	476
	477	drvdata->miscdev.name = pdata->name;
	478	drvdata->miscdev.minor = MISC_DYNAMIC_MINOR;
	479	drvdata->miscdev.fops = &etb_fops;
	480	ret = misc_register(&drvdata->miscdev);
	481	if (ret)
	482	goto err_misc_register;
	483
	484	dev_info(dev, "ETB initialized\n");
	485	return 0;
	486
	487	err_misc_register:
	488	coresight_unregister(drvdata->csdev);
	489	return ret;
	490	}
	491
	492	static int etb_remove(struct amba_device *adev)
	493	{
	494	struct etb_drvdata *drvdata = amba_get_drvdata(adev);
	495
	496	misc_deregister(&drvdata->miscdev);
	497	coresight_unregister(drvdata->csdev);
	498	return 0;
	499	}
	500
267b2c23 LW	501	#ifdef CONFIG_PM
	502	static int etb_runtime_suspend(struct device *dev)
	503	{
	504	struct etb_drvdata *drvdata = dev_get_drvdata(dev);
	505
	506	if (drvdata && !IS_ERR(drvdata->atclk))
	507	clk_disable_unprepare(drvdata->atclk);
	508
	509	return 0;
	510	}
	511
	512	static int etb_runtime_resume(struct device *dev)
	513	{
	514	struct etb_drvdata *drvdata = dev_get_drvdata(dev);
	515
	516	if (drvdata && !IS_ERR(drvdata->atclk))
	517	clk_prepare_enable(drvdata->atclk);
	518
	519	return 0;
	520	}
	521	#endif
	522
	523	static const struct dev_pm_ops etb_dev_pm_ops = {
	524	SET_RUNTIME_PM_OPS(etb_runtime_suspend, etb_runtime_resume, NULL)
	525	};
	526
fdfc0d8a PP	527	static struct amba_id etb_ids[] = {
	528	{
	529	.id = 0x0003b907,
	530	.mask = 0x0003ffff,
	531	},
	532	{ 0, 0},
	533	};
	534
	535	static struct amba_driver etb_driver = {
	536	.drv = {
	537	.name = "coresight-etb10",
	538	.owner = THIS_MODULE,
267b2c23 LW	539	.pm = &etb_dev_pm_ops,
267b2c23 LW	540
fdfc0d8a PP	541	},
	542	.probe = etb_probe,
	543	.remove = etb_remove,
	544	.id_table = etb_ids,
	545	};
	546
52d6bbb9	547	module_amba_driver(etb_driver);
fdfc0d8a PP	548
	549	MODULE_LICENSE("GPL v2");
	550	MODULE_DESCRIPTION("CoreSight Embedded Trace Buffer driver");