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Commit 91282246 authored by Mathieu Poirier's avatar Mathieu Poirier
Browse files

ARM: removing support for etb/etm in "arch/arm/kernel/" 



Removing minimal support for etb/etm to favour an implementation
that is more flexible, extensible and capable of handling more
platforms.

Also removing the only client of the old driver.  That code can
easily be replaced by entries for etb/etm in the device tree.

Signed-off-by: default avatarMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit 184901a06a366d40386e07307bcadc9eeaabbd39)
Signed-off-by: default avatarMathieu Poirier <mathieu.poirier@linaro.org>

Conflicts:
	arch/arm/include/asm/hardware/coresight.h
	arch/arm/kernel/Makefile
	arch/arm/kernel/etm.c
	arch/arm/mach-omap2/Kconfig
parent 7695bef8

arch/arm/Kconfig.debug

+0 −8
Original line number Diff line number Diff line
@@ -1297,14 +1297,6 @@ config EARLY_PRINTK 
	  kernel low-level debugging functions. Add earlyprintk to your

	  kernel parameters to enable this console.



config OC_ETM

	bool "On-chip ETM and ETB"

	depends on ARM_AMBA

	help

	  Enables the on-chip embedded trace macrocell and embedded trace

	  buffer driver that will allow you to collect traces of the

	  kernel code.



config ARM_KPROBES_TEST

	tristate "Kprobes test module"

	depends on KPROBES && MODULES

arch/arm/include/asm/hardware/coresight.h

deleted100644 → 0
+0 −157
Original line number Diff line number Diff line 
/*

 * linux/arch/arm/include/asm/hardware/coresight.h

 *

 * CoreSight components' registers

 *

 * Copyright (C) 2009 Nokia Corporation.

 * Alexander Shishkin

 *

 * 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.

 */



#ifndef __ASM_HARDWARE_CORESIGHT_H

#define __ASM_HARDWARE_CORESIGHT_H



#define TRACER_ACCESSED_BIT	0

#define TRACER_RUNNING_BIT	1

#define TRACER_CYCLE_ACC_BIT	2

#define TRACER_ACCESSED		BIT(TRACER_ACCESSED_BIT)

#define TRACER_RUNNING		BIT(TRACER_RUNNING_BIT)

#define TRACER_CYCLE_ACC	BIT(TRACER_CYCLE_ACC_BIT)



#define TRACER_TIMEOUT 10000



#define etm_writel(t, v, x) \

	(writel_relaxed((v), (t)->etm_regs + (x)))

#define etm_readl(t, x) (readl_relaxed((t)->etm_regs + (x)))



/* CoreSight Management Registers */

#define CSMR_LOCKACCESS 0xfb0

#define CSMR_LOCKSTATUS 0xfb4

#define CSMR_AUTHSTATUS 0xfb8

#define CSMR_DEVID	0xfc8

#define CSMR_DEVTYPE	0xfcc

/* CoreSight Component Registers */

#define CSCR_CLASS	0xff4



#define CS_LAR_KEY	0xc5acce55



/* ETM control register, "ETM Architecture", 3.3.1 */

#define ETMR_CTRL		0

#define ETMCTRL_POWERDOWN	1

#define ETMCTRL_PROGRAM		(1 << 10)

#define ETMCTRL_PORTSEL		(1 << 11)

#define ETMCTRL_DO_CONTEXTID	(3 << 14)

#define ETMCTRL_PORTMASK1	(7 << 4)

#define ETMCTRL_PORTMASK2	(1 << 21)

#define ETMCTRL_PORTMASK	(ETMCTRL_PORTMASK1 | ETMCTRL_PORTMASK2)

#define ETMCTRL_PORTSIZE(x) ((((x) & 7) << 4) | (!!((x) & 8)) << 21)

#define ETMCTRL_DO_CPRT		(1 << 1)

#define ETMCTRL_DATAMASK	(3 << 2)

#define ETMCTRL_DATA_DO_DATA	(1 << 2)

#define ETMCTRL_DATA_DO_ADDR	(1 << 3)

#define ETMCTRL_DATA_DO_BOTH	(ETMCTRL_DATA_DO_DATA | ETMCTRL_DATA_DO_ADDR)

#define ETMCTRL_BRANCH_OUTPUT	(1 << 8)

#define ETMCTRL_CYCLEACCURATE	(1 << 12)



/* ETM configuration code register */

#define ETMR_CONFCODE		(0x04)



/* ETM trace start/stop resource control register */

#define ETMR_TRACESSCTRL	(0x18)



/* ETM trigger event register */

#define ETMR_TRIGEVT		(0x08)



/* address access type register bits, "ETM architecture",

 * table 3-27 */

/* - access type */

#define ETMAAT_IFETCH		0

#define ETMAAT_IEXEC		1

#define ETMAAT_IEXECPASS	2

#define ETMAAT_IEXECFAIL	3

#define ETMAAT_DLOADSTORE	4

#define ETMAAT_DLOAD		5

#define ETMAAT_DSTORE		6

/* - comparison access size */

#define ETMAAT_JAVA		(0 << 3)

#define ETMAAT_THUMB		(1 << 3)

#define ETMAAT_ARM		(3 << 3)

/* - data value comparison control */

#define ETMAAT_NOVALCMP		(0 << 5)

#define ETMAAT_VALMATCH		(1 << 5)

#define ETMAAT_VALNOMATCH	(3 << 5)

/* - exact match */

#define ETMAAT_EXACTMATCH	(1 << 7)

/* - context id comparator control */

#define ETMAAT_IGNCONTEXTID	(0 << 8)

#define ETMAAT_VALUE1		(1 << 8)

#define ETMAAT_VALUE2		(2 << 8)

#define ETMAAT_VALUE3		(3 << 8)

/* - security level control */

#define ETMAAT_IGNSECURITY	(0 << 10)

#define ETMAAT_NSONLY		(1 << 10)

#define ETMAAT_SONLY		(2 << 10)



#define ETMR_COMP_VAL(x)	(0x40 + (x) * 4)

#define ETMR_COMP_ACC_TYPE(x)	(0x80 + (x) * 4)



/* ETM status register, "ETM Architecture", 3.3.2 */

#define ETMR_STATUS		(0x10)

#define ETMST_OVERFLOW		BIT(0)

#define ETMST_PROGBIT		BIT(1)

#define ETMST_STARTSTOP		BIT(2)

#define ETMST_TRIGGER		BIT(3)



#define etm_progbit(t)		(etm_readl((t), ETMR_STATUS) & ETMST_PROGBIT)

#define etm_started(t)		(etm_readl((t), ETMR_STATUS) & ETMST_STARTSTOP)

#define etm_triggered(t)	(etm_readl((t), ETMR_STATUS) & ETMST_TRIGGER)



#define ETMR_TRACEENCTRL2	0x1c

#define ETMR_TRACEENCTRL	0x24

#define ETMTE_INCLEXCL		BIT(24)

#define ETMR_TRACEENEVT		0x20

#define ETMCTRL_OPTS		(ETMCTRL_DO_CPRT | \

				ETMCTRL_DATA_DO_ADDR | \

				ETMCTRL_BRANCH_OUTPUT | \

				ETMCTRL_DO_CONTEXTID)



/* ETM management registers, "ETM Architecture", 3.5.24 */

#define ETMMR_OSLAR	0x300

#define ETMMR_OSLSR	0x304

#define ETMMR_OSSRR	0x308

#define ETMMR_PDSR	0x314



/* ETB registers, "CoreSight Components TRM", 9.3 */

#define ETBR_DEPTH		0x04

#define ETBR_STATUS		0x0c

#define ETBR_READMEM		0x10

#define ETBR_READADDR		0x14

#define ETBR_WRITEADDR		0x18

#define ETBR_TRIGGERCOUNT	0x1c

#define ETBR_CTRL		0x20

#define ETBR_FORMATTERCTRL	0x304

#define ETBFF_ENFTC		1

#define ETBFF_ENFCONT		BIT(1)

#define ETBFF_FONFLIN		BIT(4)

#define ETBFF_MANUAL_FLUSH	BIT(6)

#define ETBFF_TRIGIN		BIT(8)

#define ETBFF_TRIGEVT		BIT(9)

#define ETBFF_TRIGFL		BIT(10)



#define etb_writel(t, v, x) \

	(writel_relaxed((v), (t)->etb_regs + (x)))

#define etb_readl(t, x) (readl_relaxed((t)->etb_regs + (x)))



#define etm_lock(t) do { etm_writel((t), 0, CSMR_LOCKACCESS); } while (0)

#define etm_unlock(t) \

	do { etm_writel((t), CS_LAR_KEY, CSMR_LOCKACCESS); } while (0)



#define etb_lock(t) do { etb_writel((t), 0, CSMR_LOCKACCESS); } while (0)

#define etb_unlock(t) \

	do { etb_writel((t), CS_LAR_KEY, CSMR_LOCKACCESS); } while (0)



#endif /* __ASM_HARDWARE_CORESIGHT_H */

arch/arm/kernel/Makefile

+0 −1
Original line number Diff line number Diff line
@@ -30,7 +30,6 @@ else 
obj-y		+= entry-armv.o

endif



obj-$(CONFIG_OC_ETM)		+= etm.o

obj-$(CONFIG_CPU_IDLE)		+= cpuidle.o

obj-$(CONFIG_ISA_DMA_API)	+= dma.o

obj-$(CONFIG_FIQ)		+= fiq.o fiqasm.o

arch/arm/kernel/etm.c

deleted100644 → 0
+0 −654
Original line number Diff line number Diff line 
/*

 * linux/arch/arm/kernel/etm.c

 *

 * Driver for ARM's Embedded Trace Macrocell and Embedded Trace Buffer.

 *

 * Copyright (C) 2009 Nokia Corporation.

 * Alexander Shishkin

 *

 * 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.

 */



#include <linux/kernel.h>

#include <linux/init.h>

#include <linux/types.h>

#include <linux/io.h>

#include <linux/sysrq.h>

#include <linux/device.h>

#include <linux/clk.h>

#include <linux/amba/bus.h>

#include <linux/fs.h>

#include <linux/uaccess.h>

#include <linux/miscdevice.h>

#include <linux/vmalloc.h>

#include <linux/mutex.h>

#include <linux/module.h>

#include <asm/hardware/coresight.h>

#include <asm/sections.h>



MODULE_LICENSE("GPL");

MODULE_AUTHOR("Alexander Shishkin");



/*

 * ETM tracer state

 */

struct tracectx {

	unsigned int	etb_bufsz;

	void __iomem	*etb_regs;

	void __iomem	*etm_regs;

	unsigned long	flags;

	int		ncmppairs;

	int		etm_portsz;

	struct device	*dev;

	struct clk	*emu_clk;

	struct mutex	mutex;

};



static struct tracectx tracer;



static inline bool trace_isrunning(struct tracectx *t)

{

	return !!(t->flags & TRACER_RUNNING);

}



static int etm_setup_address_range(struct tracectx *t, int n,

		unsigned long start, unsigned long end, int exclude, int data)

{

	u32 flags = ETMAAT_ARM | ETMAAT_IGNCONTEXTID | ETMAAT_NSONLY | \

		    ETMAAT_NOVALCMP;



	if (n < 1 || n > t->ncmppairs)

		return -EINVAL;



	/* comparators and ranges are numbered starting with 1 as opposed

	 * to bits in a word */

	n--;



	if (data)

		flags |= ETMAAT_DLOADSTORE;

	else

		flags |= ETMAAT_IEXEC;



	/* first comparator for the range */

	etm_writel(t, flags, ETMR_COMP_ACC_TYPE(n * 2));

	etm_writel(t, start, ETMR_COMP_VAL(n * 2));



	/* second comparator is right next to it */

	etm_writel(t, flags, ETMR_COMP_ACC_TYPE(n * 2 + 1));

	etm_writel(t, end, ETMR_COMP_VAL(n * 2 + 1));



	flags = exclude ? ETMTE_INCLEXCL : 0;

	etm_writel(t, flags | (1 << n), ETMR_TRACEENCTRL);



	return 0;

}



static int trace_start(struct tracectx *t)

{

	u32 v;

	unsigned long timeout = TRACER_TIMEOUT;



	etb_unlock(t);



	etb_writel(t, 0, ETBR_FORMATTERCTRL);

	etb_writel(t, 1, ETBR_CTRL);



	etb_lock(t);



	/* configure etm */

	v = ETMCTRL_OPTS | ETMCTRL_PROGRAM | ETMCTRL_PORTSIZE(t->etm_portsz);



	if (t->flags & TRACER_CYCLE_ACC)

		v |= ETMCTRL_CYCLEACCURATE;



	etm_unlock(t);



	etm_writel(t, v, ETMR_CTRL);



	while (!(etm_readl(t, ETMR_CTRL) & ETMCTRL_PROGRAM) && --timeout)

		;

	if (!timeout) {

		dev_dbg(t->dev, "Waiting for progbit to assert timed out\n");

		etm_lock(t);

		return -EFAULT;

	}



	etm_setup_address_range(t, 1, (unsigned long)_stext,

			(unsigned long)_etext, 0, 0);

	etm_writel(t, 0, ETMR_TRACEENCTRL2);

	etm_writel(t, 0, ETMR_TRACESSCTRL);

	etm_writel(t, 0x6f, ETMR_TRACEENEVT);



	v &= ~ETMCTRL_PROGRAM;

	v |= ETMCTRL_PORTSEL;



	etm_writel(t, v, ETMR_CTRL);



	timeout = TRACER_TIMEOUT;

	while (etm_readl(t, ETMR_CTRL) & ETMCTRL_PROGRAM && --timeout)

		;

	if (!timeout) {

		dev_dbg(t->dev, "Waiting for progbit to deassert timed out\n");

		etm_lock(t);

		return -EFAULT;

	}



	etm_lock(t);



	t->flags |= TRACER_RUNNING;



	return 0;

}



static int trace_stop(struct tracectx *t)

{

	unsigned long timeout = TRACER_TIMEOUT;



	etm_unlock(t);



	etm_writel(t, 0x440, ETMR_CTRL);

	while (!(etm_readl(t, ETMR_CTRL) & ETMCTRL_PROGRAM) && --timeout)

		;

	if (!timeout) {

		dev_dbg(t->dev, "Waiting for progbit to assert timed out\n");

		etm_lock(t);

		return -EFAULT;

	}



	etm_lock(t);



	etb_unlock(t);

	etb_writel(t, ETBFF_MANUAL_FLUSH, ETBR_FORMATTERCTRL);



	timeout = TRACER_TIMEOUT;

	while (etb_readl(t, ETBR_FORMATTERCTRL) &

			ETBFF_MANUAL_FLUSH && --timeout)

		;

	if (!timeout) {

		dev_dbg(t->dev, "Waiting for formatter flush to commence "

				"timed out\n");

		etb_lock(t);

		return -EFAULT;

	}



	etb_writel(t, 0, ETBR_CTRL);



	etb_lock(t);



	t->flags &= ~TRACER_RUNNING;



	return 0;

}



static int etb_getdatalen(struct tracectx *t)

{

	u32 v;

	int rp, wp;



	v = etb_readl(t, ETBR_STATUS);



	if (v & 1)

		return t->etb_bufsz;



	rp = etb_readl(t, ETBR_READADDR);

	wp = etb_readl(t, ETBR_WRITEADDR);



	if (rp > wp) {

		etb_writel(t, 0, ETBR_READADDR);

		etb_writel(t, 0, ETBR_WRITEADDR);



		return 0;

	}



	return wp - rp;

}



/* sysrq+v will always stop the running trace and leave it at that */

static void etm_dump(void)

{

	struct tracectx *t = &tracer;

	u32 first = 0;

	int length;



	if (!t->etb_regs) {

		printk(KERN_INFO "No tracing hardware found\n");

		return;

	}



	if (trace_isrunning(t))

		trace_stop(t);



	etb_unlock(t);



	length = etb_getdatalen(t);



	if (length == t->etb_bufsz)

		first = etb_readl(t, ETBR_WRITEADDR);



	etb_writel(t, first, ETBR_READADDR);



	printk(KERN_INFO "Trace buffer contents length: %d\n", length);

	printk(KERN_INFO "--- ETB buffer begin ---\n");

	for (; length; length--)

		printk("%08x", cpu_to_be32(etb_readl(t, ETBR_READMEM)));

	printk(KERN_INFO "\n--- ETB buffer end ---\n");



	/* deassert the overflow bit */

	etb_writel(t, 1, ETBR_CTRL);

	etb_writel(t, 0, ETBR_CTRL);



	etb_writel(t, 0, ETBR_TRIGGERCOUNT);

	etb_writel(t, 0, ETBR_READADDR);

	etb_writel(t, 0, ETBR_WRITEADDR);



	etb_lock(t);

}



static void sysrq_etm_dump(int key)

{

	dev_dbg(tracer.dev, "Dumping ETB buffer\n");

	etm_dump();

}



static struct sysrq_key_op sysrq_etm_op = {

	.handler = sysrq_etm_dump,

	.help_msg = "etm-buffer-dump(v)",

	.action_msg = "etm",

};



static int etb_open(struct inode *inode, struct file *file)

{

	if (!tracer.etb_regs)

		return -ENODEV;



	file->private_data = &tracer;



	return nonseekable_open(inode, file);

}



static ssize_t etb_read(struct file *file, char __user *data,

		size_t len, loff_t *ppos)

{

	int total, i;

	long length;

	struct tracectx *t = file->private_data;

	u32 first = 0;

	u32 *buf;



	mutex_lock(&t->mutex);



	if (trace_isrunning(t)) {

		length = 0;

		goto out;

	}



	etb_unlock(t);



	total = etb_getdatalen(t);

	if (total == t->etb_bufsz)

		first = etb_readl(t, ETBR_WRITEADDR);



	etb_writel(t, first, ETBR_READADDR);



	length = min(total * 4, (int)len);

	buf = vmalloc(length);



	dev_dbg(t->dev, "ETB buffer length: %d\n", total);

	dev_dbg(t->dev, "ETB status reg: %x\n", etb_readl(t, ETBR_STATUS));

	for (i = 0; i < length / 4; i++)

		buf[i] = etb_readl(t, ETBR_READMEM);



	/* the only way to deassert overflow bit in ETB status is this */

	etb_writel(t, 1, ETBR_CTRL);

	etb_writel(t, 0, ETBR_CTRL);



	etb_writel(t, 0, ETBR_WRITEADDR);

	etb_writel(t, 0, ETBR_READADDR);

	etb_writel(t, 0, ETBR_TRIGGERCOUNT);



	etb_lock(t);



	length -= copy_to_user(data, buf, length);

	vfree(buf);



out:

	mutex_unlock(&t->mutex);



	return length;

}



static int etb_release(struct inode *inode, struct file *file)

{

	/* there's nothing to do here, actually */

	return 0;

}



static const struct file_operations etb_fops = {

	.owner = THIS_MODULE,

	.read = etb_read,

	.open = etb_open,

	.release = etb_release,

	.llseek = no_llseek,

};



static struct miscdevice etb_miscdev = {

	.name = "tracebuf",

	.minor = 0,

	.fops = &etb_fops,

};



static int etb_probe(struct amba_device *dev, const struct amba_id *id)

{

	struct tracectx *t = &tracer;

	int ret = 0;



	ret = amba_request_regions(dev, NULL);

	if (ret)

		goto out;



	t->etb_regs = ioremap_nocache(dev->res.start, resource_size(&dev->res));

	if (!t->etb_regs) {

		ret = -ENOMEM;

		goto out_release;

	}



	amba_set_drvdata(dev, t);



	etb_miscdev.parent = &dev->dev;



	ret = misc_register(&etb_miscdev);

	if (ret)

		goto out_unmap;



	t->emu_clk = clk_get(&dev->dev, "emu_src_ck");

	if (IS_ERR(t->emu_clk)) {

		dev_dbg(&dev->dev, "Failed to obtain emu_src_ck.\n");

		return -EFAULT;

	}



	clk_enable(t->emu_clk);



	etb_unlock(t);

	t->etb_bufsz = etb_readl(t, ETBR_DEPTH);

	dev_dbg(&dev->dev, "Size: %x\n", t->etb_bufsz);



	/* make sure trace capture is disabled */

	etb_writel(t, 0, ETBR_CTRL);

	etb_writel(t, 0x1000, ETBR_FORMATTERCTRL);

	etb_lock(t);



	dev_dbg(&dev->dev, "ETB AMBA driver initialized.\n");



out:

	return ret;



out_unmap:

	iounmap(t->etb_regs);



out_release:

	amba_release_regions(dev);



	return ret;

}



static int etb_remove(struct amba_device *dev)

{

	struct tracectx *t = amba_get_drvdata(dev);



	iounmap(t->etb_regs);

	t->etb_regs = NULL;



	clk_disable(t->emu_clk);

	clk_put(t->emu_clk);



	amba_release_regions(dev);



	return 0;

}



static struct amba_id etb_ids[] = {

	{

		.id	= 0x0003b907,

		.mask	= 0x0007ffff,

	},

	{ 0, 0 },

};



static struct amba_driver etb_driver = {

	.drv		= {

		.name	= "etb",

		.owner	= THIS_MODULE,

	},

	.probe		= etb_probe,

	.remove		= etb_remove,

	.id_table	= etb_ids,

};



/* use a sysfs file "trace_running" to start/stop tracing */

static ssize_t trace_running_show(struct kobject *kobj,

				  struct kobj_attribute *attr,

				  char *buf)

{

	return sprintf(buf, "%x\n", trace_isrunning(&tracer));

}



static ssize_t trace_running_store(struct kobject *kobj,

				   struct kobj_attribute *attr,

				   const char *buf, size_t n)

{

	unsigned int value;

	int ret;



	if (sscanf(buf, "%u", &value) != 1)

		return -EINVAL;



	mutex_lock(&tracer.mutex);

	ret = value ? trace_start(&tracer) : trace_stop(&tracer);

	mutex_unlock(&tracer.mutex);



	return ret ? : n;

}



static struct kobj_attribute trace_running_attr =

	__ATTR(trace_running, 0644, trace_running_show, trace_running_store);



static ssize_t trace_info_show(struct kobject *kobj,

				  struct kobj_attribute *attr,

				  char *buf)

{

	u32 etb_wa, etb_ra, etb_st, etb_fc, etm_ctrl, etm_st;

	int datalen;



	etb_unlock(&tracer);

	datalen = etb_getdatalen(&tracer);

	etb_wa = etb_readl(&tracer, ETBR_WRITEADDR);

	etb_ra = etb_readl(&tracer, ETBR_READADDR);

	etb_st = etb_readl(&tracer, ETBR_STATUS);

	etb_fc = etb_readl(&tracer, ETBR_FORMATTERCTRL);

	etb_lock(&tracer);



	etm_unlock(&tracer);

	etm_ctrl = etm_readl(&tracer, ETMR_CTRL);

	etm_st = etm_readl(&tracer, ETMR_STATUS);

	etm_lock(&tracer);



	return sprintf(buf, "Trace buffer len: %d\nComparator pairs: %d\n"

			"ETBR_WRITEADDR:\t%08x\n"

			"ETBR_READADDR:\t%08x\n"

			"ETBR_STATUS:\t%08x\n"

			"ETBR_FORMATTERCTRL:\t%08x\n"

			"ETMR_CTRL:\t%08x\n"

			"ETMR_STATUS:\t%08x\n",

			datalen,

			tracer.ncmppairs,

			etb_wa,

			etb_ra,

			etb_st,

			etb_fc,

			etm_ctrl,

			etm_st

			);

}



static struct kobj_attribute trace_info_attr =

	__ATTR(trace_info, 0444, trace_info_show, NULL);



static ssize_t trace_mode_show(struct kobject *kobj,

				  struct kobj_attribute *attr,

				  char *buf)

{

	return sprintf(buf, "%d %d\n",

			!!(tracer.flags & TRACER_CYCLE_ACC),

			tracer.etm_portsz);

}



static ssize_t trace_mode_store(struct kobject *kobj,

				   struct kobj_attribute *attr,

				   const char *buf, size_t n)

{

	unsigned int cycacc, portsz;



	if (sscanf(buf, "%u %u", &cycacc, &portsz) != 2)

		return -EINVAL;



	mutex_lock(&tracer.mutex);

	if (cycacc)

		tracer.flags |= TRACER_CYCLE_ACC;

	else

		tracer.flags &= ~TRACER_CYCLE_ACC;



	tracer.etm_portsz = portsz & 0x0f;

	mutex_unlock(&tracer.mutex);



	return n;

}



static struct kobj_attribute trace_mode_attr =

	__ATTR(trace_mode, 0644, trace_mode_show, trace_mode_store);



static int etm_probe(struct amba_device *dev, const struct amba_id *id)

{

	struct tracectx *t = &tracer;

	int ret = 0;



	if (t->etm_regs) {

		dev_dbg(&dev->dev, "ETM already initialized\n");

		ret = -EBUSY;

		goto out;

	}



	ret = amba_request_regions(dev, NULL);

	if (ret)

		goto out;



	t->etm_regs = ioremap_nocache(dev->res.start, resource_size(&dev->res));

	if (!t->etm_regs) {

		ret = -ENOMEM;

		goto out_release;

	}



	amba_set_drvdata(dev, t);



	mutex_init(&t->mutex);

	t->dev = &dev->dev;

	t->flags = TRACER_CYCLE_ACC;

	t->etm_portsz = 1;



	etm_unlock(t);

	(void)etm_readl(t, ETMMR_PDSR);

	/* dummy first read */

	(void)etm_readl(&tracer, ETMMR_OSSRR);



	t->ncmppairs = etm_readl(t, ETMR_CONFCODE) & 0xf;

	etm_writel(t, 0x440, ETMR_CTRL);

	etm_lock(t);



	ret = sysfs_create_file(&dev->dev.kobj,

			&trace_running_attr.attr);

	if (ret)

		goto out_unmap;



	/* failing to create any of these two is not fatal */

	ret = sysfs_create_file(&dev->dev.kobj, &trace_info_attr.attr);

	if (ret)

		dev_dbg(&dev->dev, "Failed to create trace_info in sysfs\n");



	ret = sysfs_create_file(&dev->dev.kobj, &trace_mode_attr.attr);

	if (ret)

		dev_dbg(&dev->dev, "Failed to create trace_mode in sysfs\n");



	dev_dbg(t->dev, "ETM AMBA driver initialized.\n");



out:

	return ret;



out_unmap:

	iounmap(t->etm_regs);



out_release:

	amba_release_regions(dev);



	return ret;

}



static int etm_remove(struct amba_device *dev)

{

	struct tracectx *t = amba_get_drvdata(dev);



	iounmap(t->etm_regs);

	t->etm_regs = NULL;



	amba_release_regions(dev);



	sysfs_remove_file(&dev->dev.kobj, &trace_running_attr.attr);

	sysfs_remove_file(&dev->dev.kobj, &trace_info_attr.attr);

	sysfs_remove_file(&dev->dev.kobj, &trace_mode_attr.attr);



	return 0;

}



static struct amba_id etm_ids[] = {

	{

		.id	= 0x0003b921,

		.mask	= 0x0007ffff,

	},

	{ 0, 0 },

};



static struct amba_driver etm_driver = {

	.drv		= {

		.name   = "etm",

		.owner  = THIS_MODULE,

	},

	.probe		= etm_probe,

	.remove		= etm_remove,

	.id_table	= etm_ids,

};



static int __init etm_init(void)

{

	int retval;



	retval = amba_driver_register(&etb_driver);

	if (retval) {

		printk(KERN_ERR "Failed to register etb\n");

		return retval;

	}



	retval = amba_driver_register(&etm_driver);

	if (retval) {

		amba_driver_unregister(&etb_driver);

		printk(KERN_ERR "Failed to probe etm\n");

		return retval;

	}



	/* not being able to install this handler is not fatal */

	(void)register_sysrq_key('v', &sysrq_etm_op);



	return 0;

}



device_initcall(etm_init);

arch/arm/kernel/hw_breakpoint.c

+2 −2
Original line number Diff line number Diff line
@@ -29,6 +29,7 @@ 
#include <linux/hw_breakpoint.h>

#include <linux/smp.h>

#include <linux/cpu_pm.h>

#include <linux/coresight.h>



#include <asm/cacheflush.h>

#include <asm/cputype.h>
@@ -36,7 +37,6 @@ 
#include <asm/hw_breakpoint.h>

#include <asm/kdebug.h>

#include <asm/traps.h>

#include <asm/hardware/coresight.h>



/* Breakpoint currently in use for each BRP. */

static DEFINE_PER_CPU(struct perf_event *, bp_on_reg[ARM_MAX_BRP]);
@@ -976,7 +976,7 @@ static void reset_ctrl_regs(void *unused) 
	 * Unconditionally clear the OS lock by writing a value

	 * other than CS_LAR_KEY to the access register.

	 */

	ARM_DBG_WRITE(c1, c0, 4, ~CS_LAR_KEY);

	ARM_DBG_WRITE(c1, c0, 4, ~CORESIGHT_UNLOCK);

	isb();



	/*