drivers/hwtracing/coresight/coresight-tmc-etr.c - linux - Git at Google

 /*
  * Copyright(C) 2016 Linaro Limited. All rights reserved.
  * Author: Mathieu Poirier <mathieu.poirier@linaro.org>
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License 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.
  *
  * You should have received a copy of the GNU General Public License along with
  * this program.  If not, see <http://www.gnu.org/licenses/>.
  */

 #include <linux/coresight.h>
 #include <linux/dma-mapping.h>
 #include "coresight-priv.h"
 #include "coresight-tmc.h"

 static void tmc_etr_enable_hw(struct tmc_drvdata *drvdata)
 {
 	u32 axictl;

 	/* Zero out the memory to help with debug */
 	memset(drvdata->vaddr, 0, drvdata->size);

 	CS_UNLOCK(drvdata->base);

 	/* Wait for TMCSReady bit to be set */
 	tmc_wait_for_tmcready(drvdata);

 	writel_relaxed(drvdata->size / 4, drvdata->base + TMC_RSZ);
 	writel_relaxed(TMC_MODE_CIRCULAR_BUFFER, drvdata->base + TMC_MODE);

 	axictl = readl_relaxed(drvdata->base + TMC_AXICTL);
 	axictl |= TMC_AXICTL_WR_BURST_16;
 	writel_relaxed(axictl, drvdata->base + TMC_AXICTL);
 	axictl &= ~TMC_AXICTL_SCT_GAT_MODE;
 	writel_relaxed(axictl, drvdata->base + TMC_AXICTL);
 	axictl = (axictl &
 		  ~(TMC_AXICTL_PROT_CTL_B0 | TMC_AXICTL_PROT_CTL_B1)) |
 		  TMC_AXICTL_PROT_CTL_B1;
 	writel_relaxed(axictl, drvdata->base + TMC_AXICTL);

 	writel_relaxed(drvdata->paddr, drvdata->base + TMC_DBALO);
 	writel_relaxed(0x0, drvdata->base + TMC_DBAHI);
 	writel_relaxed(TMC_FFCR_EN_FMT | TMC_FFCR_EN_TI |
 		       TMC_FFCR_FON_FLIN | TMC_FFCR_FON_TRIG_EVT |
 		       TMC_FFCR_TRIGON_TRIGIN,
 		       drvdata->base + TMC_FFCR);
 	writel_relaxed(drvdata->trigger_cntr, drvdata->base + TMC_TRG);
 	tmc_enable_hw(drvdata);

 	CS_LOCK(drvdata->base);
 }

 static void tmc_etr_dump_hw(struct tmc_drvdata *drvdata)
 {
 	u32 rwp, val;

 	rwp = readl_relaxed(drvdata->base + TMC_RWP);
 	val = readl_relaxed(drvdata->base + TMC_STS);

 	/*
 	 * Adjust the buffer to point to the beginning of the trace data
 	 * and update the available trace data.
 	 */
 	if (val & TMC_STS_FULL) {
 		drvdata->buf = drvdata->vaddr + rwp - drvdata->paddr;
 		drvdata->len = drvdata->size;
 	} else {
 		drvdata->buf = drvdata->vaddr;
 		drvdata->len = rwp - drvdata->paddr;
 	}
 }

 static void tmc_etr_disable_hw(struct tmc_drvdata *drvdata)
 {
 	CS_UNLOCK(drvdata->base);

 	tmc_flush_and_stop(drvdata);
 	/*
 	 * When operating in sysFS mode the content of the buffer needs to be
 	 * read before the TMC is disabled.
 	 */
 	if (drvdata->mode == CS_MODE_SYSFS)
 		tmc_etr_dump_hw(drvdata);
 	tmc_disable_hw(drvdata);

 	CS_LOCK(drvdata->base);
 }

 static int tmc_enable_etr_sink_sysfs(struct coresight_device *csdev)
 {
 	int ret = 0;
 	bool used = false;
 	unsigned long flags;
 	void __iomem *vaddr = NULL;
 	dma_addr_t paddr;
 	struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);


 	/*
 	 * If we don't have a buffer release the lock and allocate memory.
 	 * Otherwise keep the lock and move along.
 	 */
 	spin_lock_irqsave(&drvdata->spinlock, flags);
 	if (!drvdata->vaddr) {
 		spin_unlock_irqrestore(&drvdata->spinlock, flags);

 		/*
 		 * Contiguous  memory can't be allocated while a spinlock is
 		 * held.  As such allocate memory here and free it if a buffer
 		 * has already been allocated (from a previous session).
 		 */
 		vaddr = dma_alloc_coherent(drvdata->dev, drvdata->size,
 					   &paddr, GFP_KERNEL);
 		if (!vaddr)
 			return -ENOMEM;

 		/* Let's try again */
 		spin_lock_irqsave(&drvdata->spinlock, flags);
 	}

 	if (drvdata->reading) {
 		ret = -EBUSY;
 		goto out;
 	}

 	/*
 	 * In sysFS mode we can have multiple writers per sink.  Since this
 	 * sink is already enabled no memory is needed and the HW need not be
 	 * touched.
 	 */
 	if (drvdata->mode == CS_MODE_SYSFS)
 		goto out;

 	/*
 	 * If drvdata::buf == NULL, use the memory allocated above.
 	 * Otherwise a buffer still exists from a previous session, so
 	 * simply use that.
 	 */
 	if (drvdata->buf == NULL) {
 		used = true;
 		drvdata->vaddr = vaddr;
 		drvdata->paddr = paddr;
 		drvdata->buf = drvdata->vaddr;
 	}

 	drvdata->mode = CS_MODE_SYSFS;
 	tmc_etr_enable_hw(drvdata);
 out:
 	spin_unlock_irqrestore(&drvdata->spinlock, flags);

 	/* Free memory outside the spinlock if need be */
 	if (!used && vaddr)
 		dma_free_coherent(drvdata->dev, drvdata->size, vaddr, paddr);

 	if (!ret)
 		dev_info(drvdata->dev, "TMC-ETR enabled\n");

 	return ret;
 }

 static int tmc_enable_etr_sink_perf(struct coresight_device *csdev)
 {
 	int ret = 0;
 	unsigned long flags;
 	struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);

 	spin_lock_irqsave(&drvdata->spinlock, flags);
 	if (drvdata->reading) {
 		ret = -EINVAL;
 		goto out;
 	}

 	/*
 	 * In Perf mode there can be only one writer per sink.  There
 	 * is also no need to continue if the ETR is already operated
 	 * from sysFS.
 	 */
 	if (drvdata->mode != CS_MODE_DISABLED) {
 		ret = -EINVAL;
 		goto out;
 	}

 	drvdata->mode = CS_MODE_PERF;
 	tmc_etr_enable_hw(drvdata);
 out:
 	spin_unlock_irqrestore(&drvdata->spinlock, flags);

 	return ret;
 }

 static int tmc_enable_etr_sink(struct coresight_device *csdev, u32 mode)
 {
 	switch (mode) {
 	case CS_MODE_SYSFS:
 		return tmc_enable_etr_sink_sysfs(csdev);
 	case CS_MODE_PERF:
 		return tmc_enable_etr_sink_perf(csdev);
 	}

 	/* We shouldn't be here */
 	return -EINVAL;
 }

 static void tmc_disable_etr_sink(struct coresight_device *csdev)
 {
 	unsigned long flags;
 	struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);

 	spin_lock_irqsave(&drvdata->spinlock, flags);
 	if (drvdata->reading) {
 		spin_unlock_irqrestore(&drvdata->spinlock, flags);
 		return;
 	}

 	/* Disable the TMC only if it needs to */
 	if (drvdata->mode != CS_MODE_DISABLED) {
 		tmc_etr_disable_hw(drvdata);
 		drvdata->mode = CS_MODE_DISABLED;
 	}

 	spin_unlock_irqrestore(&drvdata->spinlock, flags);

 	dev_info(drvdata->dev, "TMC-ETR disabled\n");
 }

 static const struct coresight_ops_sink tmc_etr_sink_ops = {
 	.enable		= tmc_enable_etr_sink,
 	.disable	= tmc_disable_etr_sink,
 };

 const struct coresight_ops tmc_etr_cs_ops = {
 	.sink_ops	= &tmc_etr_sink_ops,
 };

 int tmc_read_prepare_etr(struct tmc_drvdata *drvdata)
 {
 	int ret = 0;
 	unsigned long flags;

 	/* config types are set a boot time and never change */
 	if (WARN_ON_ONCE(drvdata->config_type != TMC_CONFIG_TYPE_ETR))
 		return -EINVAL;

 	spin_lock_irqsave(&drvdata->spinlock, flags);
 	if (drvdata->reading) {
 		ret = -EBUSY;
 		goto out;
 	}

 	/* Don't interfere if operated from Perf */
 	if (drvdata->mode == CS_MODE_PERF) {
 		ret = -EINVAL;
 		goto out;
 	}

 	/* If drvdata::buf is NULL the trace data has been read already */
 	if (drvdata->buf == NULL) {
 		ret = -EINVAL;
 		goto out;
 	}

 	/* Disable the TMC if need be */
 	if (drvdata->mode == CS_MODE_SYSFS)
 		tmc_etr_disable_hw(drvdata);

 	drvdata->reading = true;
 out:
 	spin_unlock_irqrestore(&drvdata->spinlock, flags);

 	return ret;
 }

 int tmc_read_unprepare_etr(struct tmc_drvdata *drvdata)
 {
 	unsigned long flags;
 	dma_addr_t paddr;
 	void __iomem *vaddr = NULL;

 	/* config types are set a boot time and never change */
 	if (WARN_ON_ONCE(drvdata->config_type != TMC_CONFIG_TYPE_ETR))
 		return -EINVAL;

 	spin_lock_irqsave(&drvdata->spinlock, flags);

 	/* RE-enable the TMC if need be */
 	if (drvdata->mode == CS_MODE_SYSFS) {
 		/*
 		 * The trace run will continue with the same allocated trace
 		 * buffer. The trace buffer is cleared in tmc_etr_enable_hw(),
 		 * so we don't have to explicitly clear it. Also, since the
 		 * tracer is still enabled drvdata::buf can't be NULL.
 		 */
 		tmc_etr_enable_hw(drvdata);
 	} else {
 		/*
 		 * The ETR is not tracing and the buffer was just read.
 		 * As such prepare to free the trace buffer.
 		 */
 		vaddr = drvdata->vaddr;
 		paddr = drvdata->paddr;
 		drvdata->buf = drvdata->vaddr = NULL;
 	}

 	drvdata->reading = false;
 	spin_unlock_irqrestore(&drvdata->spinlock, flags);

 	/* Free allocated memory out side of the spinlock */
 	if (vaddr)
 		dma_free_coherent(drvdata->dev, drvdata->size, vaddr, paddr);

 	return 0;
 }
	/*
	* Copyright(C) 2016 Linaro Limited. All rights reserved.
	* Author: Mathieu Poirier <mathieu.poirier@linaro.org>
	*
	* This program is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License 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.
	*
	* You should have received a copy of the GNU General Public License along with
	* this program. If not, see <http://www.gnu.org/licenses/>.
	*/

	#include <linux/coresight.h>
	#include <linux/dma-mapping.h>
	#include "coresight-priv.h"
	#include "coresight-tmc.h"

	static void tmc_etr_enable_hw(struct tmc_drvdata *drvdata)
	{
	u32 axictl;

	/* Zero out the memory to help with debug */
	memset(drvdata->vaddr, 0, drvdata->size);

	CS_UNLOCK(drvdata->base);

	/* Wait for TMCSReady bit to be set */
	tmc_wait_for_tmcready(drvdata);

	writel_relaxed(drvdata->size / 4, drvdata->base + TMC_RSZ);
	writel_relaxed(TMC_MODE_CIRCULAR_BUFFER, drvdata->base + TMC_MODE);

	axictl = readl_relaxed(drvdata->base + TMC_AXICTL);
	axictl \|= TMC_AXICTL_WR_BURST_16;
	writel_relaxed(axictl, drvdata->base + TMC_AXICTL);
	axictl &= ~TMC_AXICTL_SCT_GAT_MODE;
	writel_relaxed(axictl, drvdata->base + TMC_AXICTL);
	axictl = (axictl &
	~(TMC_AXICTL_PROT_CTL_B0 \| TMC_AXICTL_PROT_CTL_B1)) \|
	TMC_AXICTL_PROT_CTL_B1;
	writel_relaxed(axictl, drvdata->base + TMC_AXICTL);

	writel_relaxed(drvdata->paddr, drvdata->base + TMC_DBALO);
	writel_relaxed(0x0, drvdata->base + TMC_DBAHI);
	writel_relaxed(TMC_FFCR_EN_FMT \| TMC_FFCR_EN_TI \|
	TMC_FFCR_FON_FLIN \| TMC_FFCR_FON_TRIG_EVT \|
	TMC_FFCR_TRIGON_TRIGIN,
	drvdata->base + TMC_FFCR);
	writel_relaxed(drvdata->trigger_cntr, drvdata->base + TMC_TRG);
	tmc_enable_hw(drvdata);

	CS_LOCK(drvdata->base);
	}

	static void tmc_etr_dump_hw(struct tmc_drvdata *drvdata)
	{
	u32 rwp, val;

	rwp = readl_relaxed(drvdata->base + TMC_RWP);
	val = readl_relaxed(drvdata->base + TMC_STS);

	/*
	* Adjust the buffer to point to the beginning of the trace data
	* and update the available trace data.
	*/
	if (val & TMC_STS_FULL) {
	drvdata->buf = drvdata->vaddr + rwp - drvdata->paddr;
	drvdata->len = drvdata->size;
	} else {
	drvdata->buf = drvdata->vaddr;
	drvdata->len = rwp - drvdata->paddr;
	}
	}

	static void tmc_etr_disable_hw(struct tmc_drvdata *drvdata)
	{
	CS_UNLOCK(drvdata->base);

	tmc_flush_and_stop(drvdata);
	/*
	* When operating in sysFS mode the content of the buffer needs to be
	* read before the TMC is disabled.
	*/
	if (drvdata->mode == CS_MODE_SYSFS)
	tmc_etr_dump_hw(drvdata);
	tmc_disable_hw(drvdata);

	CS_LOCK(drvdata->base);
	}

	static int tmc_enable_etr_sink_sysfs(struct coresight_device *csdev)
	{
	int ret = 0;
	bool used = false;
	unsigned long flags;
	void __iomem *vaddr = NULL;
	dma_addr_t paddr;
	struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);


	/*
	* If we don't have a buffer release the lock and allocate memory.
	* Otherwise keep the lock and move along.
	*/
	spin_lock_irqsave(&drvdata->spinlock, flags);
	if (!drvdata->vaddr) {
	spin_unlock_irqrestore(&drvdata->spinlock, flags);

	/*
	* Contiguous memory can't be allocated while a spinlock is
	* held. As such allocate memory here and free it if a buffer
	* has already been allocated (from a previous session).
	*/
	vaddr = dma_alloc_coherent(drvdata->dev, drvdata->size,
	&paddr, GFP_KERNEL);
	if (!vaddr)
	return -ENOMEM;

	/* Let's try again */
	spin_lock_irqsave(&drvdata->spinlock, flags);
	}

	if (drvdata->reading) {
	ret = -EBUSY;
	goto out;
	}

	/*
	* In sysFS mode we can have multiple writers per sink. Since this
	* sink is already enabled no memory is needed and the HW need not be
	* touched.
	*/
	if (drvdata->mode == CS_MODE_SYSFS)
	goto out;

	/*
	* If drvdata::buf == NULL, use the memory allocated above.
	* Otherwise a buffer still exists from a previous session, so
	* simply use that.
	*/
	if (drvdata->buf == NULL) {
	used = true;
	drvdata->vaddr = vaddr;
	drvdata->paddr = paddr;
	drvdata->buf = drvdata->vaddr;
	}

	drvdata->mode = CS_MODE_SYSFS;
	tmc_etr_enable_hw(drvdata);
	out:
	spin_unlock_irqrestore(&drvdata->spinlock, flags);

	/* Free memory outside the spinlock if need be */
	if (!used && vaddr)
	dma_free_coherent(drvdata->dev, drvdata->size, vaddr, paddr);

	if (!ret)
	dev_info(drvdata->dev, "TMC-ETR enabled\n");

	return ret;
	}

	static int tmc_enable_etr_sink_perf(struct coresight_device *csdev)
	{
	int ret = 0;
	unsigned long flags;
	struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);

	spin_lock_irqsave(&drvdata->spinlock, flags);
	if (drvdata->reading) {
	ret = -EINVAL;
	goto out;
	}

	/*
	* In Perf mode there can be only one writer per sink. There
	* is also no need to continue if the ETR is already operated
	* from sysFS.
	*/
	if (drvdata->mode != CS_MODE_DISABLED) {
	ret = -EINVAL;
	goto out;
	}

	drvdata->mode = CS_MODE_PERF;
	tmc_etr_enable_hw(drvdata);
	out:
	spin_unlock_irqrestore(&drvdata->spinlock, flags);

	return ret;
	}

	static int tmc_enable_etr_sink(struct coresight_device *csdev, u32 mode)
	{
	switch (mode) {
	case CS_MODE_SYSFS:
	return tmc_enable_etr_sink_sysfs(csdev);
	case CS_MODE_PERF:
	return tmc_enable_etr_sink_perf(csdev);
	}

	/* We shouldn't be here */
	return -EINVAL;
	}

	static void tmc_disable_etr_sink(struct coresight_device *csdev)
	{
	unsigned long flags;
	struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);

	spin_lock_irqsave(&drvdata->spinlock, flags);
	if (drvdata->reading) {
	spin_unlock_irqrestore(&drvdata->spinlock, flags);
	return;
	}

	/* Disable the TMC only if it needs to */
	if (drvdata->mode != CS_MODE_DISABLED) {
	tmc_etr_disable_hw(drvdata);
	drvdata->mode = CS_MODE_DISABLED;
	}

	spin_unlock_irqrestore(&drvdata->spinlock, flags);

	dev_info(drvdata->dev, "TMC-ETR disabled\n");
	}

	static const struct coresight_ops_sink tmc_etr_sink_ops = {
	.enable = tmc_enable_etr_sink,
	.disable = tmc_disable_etr_sink,
	};

	const struct coresight_ops tmc_etr_cs_ops = {
	.sink_ops = &tmc_etr_sink_ops,
	};

	int tmc_read_prepare_etr(struct tmc_drvdata *drvdata)
	{
	int ret = 0;
	unsigned long flags;

	/* config types are set a boot time and never change */
	if (WARN_ON_ONCE(drvdata->config_type != TMC_CONFIG_TYPE_ETR))
	return -EINVAL;

	spin_lock_irqsave(&drvdata->spinlock, flags);
	if (drvdata->reading) {
	ret = -EBUSY;
	goto out;
	}

	/* Don't interfere if operated from Perf */
	if (drvdata->mode == CS_MODE_PERF) {
	ret = -EINVAL;
	goto out;
	}

	/* If drvdata::buf is NULL the trace data has been read already */
	if (drvdata->buf == NULL) {
	ret = -EINVAL;
	goto out;
	}

	/* Disable the TMC if need be */
	if (drvdata->mode == CS_MODE_SYSFS)
	tmc_etr_disable_hw(drvdata);

	drvdata->reading = true;
	out:
	spin_unlock_irqrestore(&drvdata->spinlock, flags);

	return ret;
	}

	int tmc_read_unprepare_etr(struct tmc_drvdata *drvdata)
	{
	unsigned long flags;
	dma_addr_t paddr;
	void __iomem *vaddr = NULL;

	/* config types are set a boot time and never change */
	if (WARN_ON_ONCE(drvdata->config_type != TMC_CONFIG_TYPE_ETR))
	return -EINVAL;

	spin_lock_irqsave(&drvdata->spinlock, flags);

	/* RE-enable the TMC if need be */
	if (drvdata->mode == CS_MODE_SYSFS) {
	/*
	* The trace run will continue with the same allocated trace
	* buffer. The trace buffer is cleared in tmc_etr_enable_hw(),
	* so we don't have to explicitly clear it. Also, since the
	* tracer is still enabled drvdata::buf can't be NULL.
	*/
	tmc_etr_enable_hw(drvdata);
	} else {
	/*
	* The ETR is not tracing and the buffer was just read.
	* As such prepare to free the trace buffer.
	*/
	vaddr = drvdata->vaddr;
	paddr = drvdata->paddr;
	drvdata->buf = drvdata->vaddr = NULL;
	}

	drvdata->reading = false;
	spin_unlock_irqrestore(&drvdata->spinlock, flags);

	/* Free allocated memory out side of the spinlock */
	if (vaddr)
	dma_free_coherent(drvdata->dev, drvdata->size, vaddr, paddr);

	return 0;
	}