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

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: Mathieu Poirier <mathieu.poirier@linaro.org>

3 files changed, 2 insertions, 657 deletions

diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile
index 38ddd9f83d0e..9e80b984219a 100644
--- a/arch/arm/kernel/Makefile
+++ b/arch/arm/kernel/Makefile
@@ -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
diff --git a/arch/arm/kernel/etm.c b/arch/arm/kernel/etm.c
deleted file mode 100644
index 131a6ab5f355..000000000000
--- a/arch/arm/kernel/etm.c
+++ /dev/null
@@ -1,654 +0,0 @@
-/*
- * 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);
-
diff --git a/arch/arm/kernel/hw_breakpoint.c b/arch/arm/kernel/hw_breakpoint.c
index b5b452f90f76..7fc70ae21185 100644
--- a/arch/arm/kernel/hw_breakpoint.c
+++ b/arch/arm/kernel/hw_breakpoint.c
@@ -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();
 
 	/*