[PATCH 8/8] ARM: etm: Support multiple ETMs/PTMs.

["Arve Hjønnevåg" <arve@android.com>]

If more than one ETM or PTM are present, configure all of them
and enable the formatter in the ETB. This allows tracing on dual
core systems (e.g. omap4).

Signed-off-by: Arve Hjønnevåg <arve@android.com>
---
 arch/arm/include/asm/hardware/coresight.h |   16 ++-
 arch/arm/kernel/etm.c                     |  234 +++++++++++++++++++----------
 2 files changed, 166 insertions(+), 84 deletions(-)

diff --git a/arch/arm/include/asm/hardware/coresight.h b/arch/arm/include/asm/hardware/coresight.h
index 6ea507f..6643d6c 100644
--- a/arch/arm/include/asm/hardware/coresight.h
+++ b/arch/arm/include/asm/hardware/coresight.h
@@ -25,9 +25,9 @@
 
 #define TRACER_TIMEOUT 10000
 
-#define etm_writel(t, v, x) \
-	(__raw_writel((v), (t)->etm_regs + (x)))
-#define etm_readl(t, x) (__raw_readl((t)->etm_regs + (x)))
+#define etm_writel(t, id, v, x) \
+	(__raw_writel((v), (t)->etm_regs[(id)] + (x)))
+#define etm_readl(t, id, x) (__raw_readl((t)->etm_regs[(id)] + (x)))
 
 /* CoreSight Management Registers */
 #define CSMR_LOCKACCESS 0xfb0
@@ -126,6 +126,8 @@
 				ETMCTRL_BRANCH_OUTPUT | \
 				ETMCTRL_DO_CONTEXTID)
 
+#define ETMR_TRACEIDR		0x200
+
 /* ETM management registers, "ETM Architecture", 3.5.24 */
 #define ETMMR_OSLAR	0x300
 #define ETMMR_OSLSR	0x304
@@ -148,14 +150,16 @@
 #define ETBFF_TRIGIN		BIT(8)
 #define ETBFF_TRIGEVT		BIT(9)
 #define ETBFF_TRIGFL		BIT(10)
+#define ETBFF_STOPFL		BIT(12)
 
 #define etb_writel(t, v, x) \
 	(__raw_writel((v), (t)->etb_regs + (x)))
 #define etb_readl(t, x) (__raw_readl((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), UNLOCK_MAGIC, CSMR_LOCKACCESS); } while (0)
+#define etm_lock(t, id) \
+	do { etm_writel((t), (id), 0, CSMR_LOCKACCESS); } while (0)
+#define etm_unlock(t, id) \
+	do { etm_writel((t), (id), UNLOCK_MAGIC, CSMR_LOCKACCESS); } while (0)
 
 #define etb_lock(t) do { etb_writel((t), 0, CSMR_LOCKACCESS); } while (0)
 #define etb_unlock(t) \
diff --git a/arch/arm/kernel/etm.c b/arch/arm/kernel/etm.c
index 4ad1257..48de5a4 100644
--- a/arch/arm/kernel/etm.c
+++ b/arch/arm/kernel/etm.c
@@ -15,6 +15,7 @@
 #include <linux/init.h>
 #include <linux/types.h>
 #include <linux/io.h>
+#include <linux/slab.h>
 #include <linux/sysrq.h>
 #include <linux/device.h>
 #include <linux/clk.h>
@@ -36,10 +37,12 @@ MODULE_AUTHOR("Alexander Shishkin");
 struct tracectx {
 	unsigned int	etb_bufsz;
 	void __iomem	*etb_regs;
-	void __iomem	*etm_regs;
+	void __iomem	**etm_regs;
+	int		etm_regs_count;
 	unsigned long	flags;
 	int		ncmppairs;
 	int		etm_portsz;
+	u32		etb_fc;
 	unsigned long	range_start;
 	unsigned long	range_end;
 	unsigned long	data_range_start;
@@ -60,7 +63,7 @@ static inline bool trace_isrunning(struct tracectx *t)
 	return !!(t->flags & TRACER_RUNNING);
 }
 
-static int etm_setup_address_range(struct tracectx *t, int n,
+static int etm_setup_address_range(struct tracectx *t, int id, int n,
 		unsigned long start, unsigned long end, int exclude, int data)
 {
 	u32 flags = ETMAAT_ARM | ETMAAT_IGNCONTEXTID | ETMAAT_IGNSECURITY |
@@ -79,41 +82,31 @@ static int etm_setup_address_range(struct tracectx *t, int n,
 		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));
+	etm_writel(t, id, flags, ETMR_COMP_ACC_TYPE(n * 2));
+	etm_writel(t, id, 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));
+	etm_writel(t, id, flags, ETMR_COMP_ACC_TYPE(n * 2 + 1));
+	etm_writel(t, id, end, ETMR_COMP_VAL(n * 2 + 1));
 
 	if (data) {
 		flags = exclude ? ETMVDC3_EXCLONLY : 0;
 		if (exclude)
 			n += 8;
-		etm_writel(t, flags | BIT(n), ETMR_VIEWDATACTRL3);
+		etm_writel(t, id, flags | BIT(n), ETMR_VIEWDATACTRL3);
 	} else {
 		flags = exclude ? ETMTE_INCLEXCL : 0;
-		etm_writel(t, flags | (1 << n), ETMR_TRACEENCTRL);
+		etm_writel(t, id, flags | (1 << n), ETMR_TRACEENCTRL);
 	}
 
 	return 0;
 }
 
-static int trace_start(struct tracectx *t)
+static int trace_start_etm(struct tracectx *t, int id)
 {
 	u32 v;
 	unsigned long timeout = TRACER_TIMEOUT;
 
-	etb_unlock(t);
-
-	t->dump_initial_etb = false;
-	etb_writel(t, 0, ETBR_WRITEADDR);
-	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)
@@ -122,79 +115,122 @@ static int trace_start(struct tracectx *t)
 	if (t->flags & TRACER_TRACE_DATA)
 		v |= ETMCTRL_DATA_DO_ADDR;
 
-	etm_unlock(t);
+	etm_unlock(t, id);
 
-	etm_writel(t, v, ETMR_CTRL);
+	etm_writel(t, id, v, ETMR_CTRL);
 
-	while (!(etm_readl(t, ETMR_CTRL) & ETMCTRL_PROGRAM) && --timeout)
+	while (!(etm_readl(t, id, ETMR_CTRL) & ETMCTRL_PROGRAM) && --timeout)
 		;
 	if (!timeout) {
 		dev_dbg(t->dev, "Waiting for progbit to assert timed out\n");
-		etm_lock(t);
+		etm_lock(t, id);
 		return -EFAULT;
 	}
 
 	if (t->range_start || t->range_end)
-		etm_setup_address_range(t, 1,
+		etm_setup_address_range(t, id, 1,
 					t->range_start, t->range_end, 0, 0);
 	else
-		etm_writel(t, ETMTE_INCLEXCL, ETMR_TRACEENCTRL);
+		etm_writel(t, id, ETMTE_INCLEXCL, ETMR_TRACEENCTRL);
 
-	etm_writel(t, 0, ETMR_TRACEENCTRL2);
-	etm_writel(t, 0, ETMR_TRACESSCTRL);
-	etm_writel(t, 0x6f, ETMR_TRACEENEVT);
+	etm_writel(t, id, 0, ETMR_TRACEENCTRL2);
+	etm_writel(t, id, 0, ETMR_TRACESSCTRL);
+	etm_writel(t, id, 0x6f, ETMR_TRACEENEVT);
 
-	etm_writel(t, 0, ETMR_VIEWDATACTRL1);
-	etm_writel(t, 0, ETMR_VIEWDATACTRL2);
+	etm_writel(t, id, 0, ETMR_VIEWDATACTRL1);
+	etm_writel(t, id, 0, ETMR_VIEWDATACTRL2);
 
 	if (t->data_range_start || t->data_range_end)
-		etm_setup_address_range(t, 2, t->data_range_start,
+		etm_setup_address_range(t, id, 2, t->data_range_start,
 					t->data_range_end, 0, 1);
 	else
-		etm_writel(t, ETMVDC3_EXCLONLY, ETMR_VIEWDATACTRL3);
+		etm_writel(t, id, ETMVDC3_EXCLONLY, ETMR_VIEWDATACTRL3);
 
-	etm_writel(t, 0x6f, ETMR_VIEWDATAEVT);
+	etm_writel(t, id, 0x6f, ETMR_VIEWDATAEVT);
 
 	v &= ~ETMCTRL_PROGRAM;
 	v |= ETMCTRL_PORTSEL;
 
-	etm_writel(t, v, ETMR_CTRL);
+	etm_writel(t, id, v, ETMR_CTRL);
 
 	timeout = TRACER_TIMEOUT;
-	while (etm_readl(t, ETMR_CTRL) & ETMCTRL_PROGRAM && --timeout)
+	while (etm_readl(t, id, ETMR_CTRL) & ETMCTRL_PROGRAM && --timeout)
 		;
 	if (!timeout) {
 		dev_dbg(t->dev, "Waiting for progbit to deassert timed out\n");
-		etm_lock(t);
+		etm_lock(t, id);
 		return -EFAULT;
 	}
 
-	etm_lock(t);
+	etm_lock(t, id);
+	return 0;
+}
+
+static int trace_start(struct tracectx *t)
+{
+	int ret;
+	int id;
+	u32 etb_fc = t->etb_fc;
+
+	etb_unlock(t);
+
+	t->dump_initial_etb = false;
+	etb_writel(t, 0, ETBR_WRITEADDR);
+	etb_writel(t, etb_fc, ETBR_FORMATTERCTRL);
+	etb_writel(t, 1, ETBR_CTRL);
+
+	etb_lock(t);
+
+	/* configure etm(s) */
+	for (id = 0; id < t->etm_regs_count; id++) {
+		ret = trace_start_etm(t, id);
+		if (ret)
+			return ret;
+	}
 
 	t->flags |= TRACER_RUNNING;
 
 	return 0;
 }
 
-static int trace_stop(struct tracectx *t)
+static int trace_stop_etm(struct tracectx *t, int id)
 {
 	unsigned long timeout = TRACER_TIMEOUT;
 
-	etm_unlock(t);
+	etm_unlock(t, id);
 
-	etm_writel(t, 0x440, ETMR_CTRL);
-	while (!(etm_readl(t, ETMR_CTRL) & ETMCTRL_PROGRAM) && --timeout)
+	etm_writel(t, id, 0x440, ETMR_CTRL);
+	while (!(etm_readl(t, id, ETMR_CTRL) & ETMCTRL_PROGRAM) && --timeout)
 		;
 	if (!timeout) {
 		dev_dbg(t->dev, "Waiting for progbit to assert timed out\n");
-		etm_lock(t);
+		etm_lock(t, id);
 		return -EFAULT;
 	}
 
-	etm_lock(t);
+	etm_lock(t, id);
+	return 0;
+}
+
+static int trace_stop(struct tracectx *t)
+{
+	int id;
+	int ret;
+	unsigned long timeout = TRACER_TIMEOUT;
+	u32 etb_fc = t->etb_fc;
+
+	for (id = 0; id < t->etm_regs_count; id++) {
+		ret = trace_stop_etm(t, id);
+		if (ret)
+			return ret;
+	}
 
 	etb_unlock(t);
-	etb_writel(t, ETBFF_MANUAL_FLUSH, ETBR_FORMATTERCTRL);
+	if (etb_fc) {
+		etb_fc |= ETBFF_STOPFL;
+		etb_writel(t, t->etb_fc, ETBR_FORMATTERCTRL);
+	}
+	etb_writel(t, etb_fc | ETBFF_MANUAL_FLUSH, ETBR_FORMATTERCTRL);
 
 	timeout = TRACER_TIMEOUT;
 	while (etb_readl(t, ETBR_FORMATTERCTRL) &
@@ -389,6 +425,7 @@ static int __init etb_probe(struct amba_device *dev, struct amba_id *id)
 		goto out_release;
 	}
 
+	t->dev = &dev->dev;
 	t->dump_initial_etb = true;
 	amba_set_drvdata(dev, t);
 
@@ -507,6 +544,8 @@ static ssize_t trace_info_show(struct kobject *kobj,
 {
 	u32 etb_wa, etb_ra, etb_st, etb_fc, etm_ctrl, etm_st;
 	int datalen;
+	int id;
+	int ret;
 
 	mutex_lock(&tracer.mutex);
 	if (tracer.etb_regs) {
@@ -522,28 +561,33 @@ static ssize_t trace_info_show(struct kobject *kobj,
 		datalen = -1;
 	}
 
-	etm_unlock(&tracer);
-	etm_ctrl = etm_readl(&tracer, ETMR_CTRL);
-	etm_st = etm_readl(&tracer, ETMR_STATUS);
-	etm_lock(&tracer);
-	mutex_unlock(&tracer.mutex);
-
-	return sprintf(buf, "Trace buffer len: %d\nComparator pairs: %d\n"
+	ret = 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",
+			"ETBR_FORMATTERCTRL:\t%08x\n",
 			datalen,
 			tracer.ncmppairs,
 			etb_wa,
 			etb_ra,
 			etb_st,
-			etb_fc,
+			etb_fc
+			);
+
+	for (id = 0; id < tracer.etm_regs_count; id++) {
+		etm_unlock(&tracer, id);
+		etm_ctrl = etm_readl(&tracer, id, ETMR_CTRL);
+		etm_st = etm_readl(&tracer, id, ETMR_STATUS);
+		etm_lock(&tracer, id);
+		ret += sprintf(buf + ret, "ETMR_CTRL:\t%08x\n"
+			"ETMR_STATUS:\t%08x\n",
 			etm_ctrl,
 			etm_st
 			);
+	}
+	mutex_unlock(&tracer.mutex);
+
+	return ret;
 }
 
 static struct kobj_attribute trace_info_attr =
@@ -657,37 +701,46 @@ static int __init etm_probe(struct amba_device *dev, struct amba_id *id)
 {
 	struct tracectx *t = &tracer;
 	int ret = 0;
+	void __iomem **new_regs;
+	int new_count;
 
-	if (t->etm_regs) {
-		dev_dbg(&dev->dev, "ETM already initialized\n");
-		ret = -EBUSY;
+	mutex_lock(&t->mutex);
+	new_count = t->etm_regs_count + 1;
+	new_regs = krealloc(t->etm_regs,
+				sizeof(t->etm_regs[0]) * new_count, GFP_KERNEL);
+
+	if (!new_regs) {
+		dev_dbg(&dev->dev, "Failed to allocate ETM register array\n");
+		ret = -ENOMEM;
 		goto out;
 	}
+	t->etm_regs = new_regs;
 
 	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) {
+	t->etm_regs[t->etm_regs_count] =
+		ioremap_nocache(dev->res.start, resource_size(&dev->res));
+	if (!t->etm_regs[t->etm_regs_count]) {
 		ret = -ENOMEM;
 		goto out_release;
 	}
 
-	amba_set_drvdata(dev, t);
+	amba_set_drvdata(dev, t->etm_regs[t->etm_regs_count]);
 
-	t->dev = &dev->dev;
 	t->flags = TRACER_CYCLE_ACC | TRACER_TRACE_DATA;
 	t->etm_portsz = 1;
 
-	etm_unlock(t);
-	(void)etm_readl(t, ETMMR_PDSR);
+	etm_unlock(t, t->etm_regs_count);
+	(void)etm_readl(t, t->etm_regs_count, ETMMR_PDSR);
 	/* dummy first read */
-	(void)etm_readl(&tracer, ETMMR_OSSRR);
+	(void)etm_readl(&tracer, t->etm_regs_count, ETMMR_OSSRR);
 
-	t->ncmppairs = etm_readl(t, ETMR_CONFCODE) & 0xf;
-	etm_writel(t, 0x440, ETMR_CTRL);
-	etm_lock(t);
+	t->ncmppairs = etm_readl(t, t->etm_regs_count, ETMR_CONFCODE) & 0xf;
+	etm_writel(t, t->etm_regs_count, 0x440, ETMR_CTRL);
+	etm_writel(t, t->etm_regs_count, new_count, ETMR_TRACEIDR);
+	etm_lock(t, t->etm_regs_count);
 
 	ret = sysfs_create_file(&dev->dev.kobj,
 			&trace_running_attr.attr);
@@ -712,31 +765,34 @@ static int __init etm_probe(struct amba_device *dev, struct amba_id *id)
 		dev_dbg(&dev->dev,
 			"Failed to create trace_data_range in sysfs\n");
 
-	dev_dbg(t->dev, "ETM AMBA driver initialized.\n");
+	dev_dbg(&dev->dev, "ETM AMBA driver initialized.\n");
+
+	/* Enable formatter if there are multiple trace sources */
+	if (new_count > 1)
+		t->etb_fc = ETBFF_ENFCONT | ETBFF_ENFTC;
+
+	t->etm_regs_count = new_count;
 
 out:
+	mutex_unlock(&t->mutex);
 	return ret;
 
 out_unmap:
 	amba_set_drvdata(dev, NULL);
-	iounmap(t->etm_regs);
+	iounmap(t->etm_regs[t->etm_regs_count]);
 
 out_release:
 	amba_release_regions(dev);
 
+	mutex_unlock(&t->mutex);
 	return ret;
 }
 
 static int etm_remove(struct amba_device *dev)
 {
-	struct tracectx *t = amba_get_drvdata(dev);
-
-	amba_set_drvdata(dev, NULL);
-
-	iounmap(t->etm_regs);
-	t->etm_regs = NULL;
-
-	amba_release_regions(dev);
+	int i;
+	struct tracectx *t = &tracer;
+	void __iomem	*etm_regs = amba_get_drvdata(dev);
 
 	sysfs_remove_file(&dev->dev.kobj, &trace_running_attr.attr);
 	sysfs_remove_file(&dev->dev.kobj, &trace_info_attr.attr);
@@ -744,6 +800,24 @@ static int etm_remove(struct amba_device *dev)
 	sysfs_remove_file(&dev->dev.kobj, &trace_range_attr.attr);
 	sysfs_remove_file(&dev->dev.kobj, &trace_data_range_attr.attr);
 
+	amba_set_drvdata(dev, NULL);
+
+	mutex_lock(&t->mutex);
+	for (i = 0; i < t->etm_regs_count; i++)
+		if (t->etm_regs[i] == etm_regs)
+			break;
+	for (; i < t->etm_regs_count - 1; i++)
+		t->etm_regs[i] = t->etm_regs[i + 1];
+	t->etm_regs_count--;
+	if (!t->etm_regs_count) {
+		kfree(t->etm_regs);
+		t->etm_regs = NULL;
+	}
+	mutex_unlock(&t->mutex);
+
+	iounmap(etm_regs);
+	amba_release_regions(dev);
+
 	return 0;
 }
 
@@ -752,6 +826,10 @@ static struct amba_id etm_ids[] = {
 		.id	= 0x0003b921,
 		.mask	= 0x0007ffff,
 	},
+	{
+		.id	= 0x0003b950,
+		.mask	= 0x0007ffff,
+	},
 	{ 0, 0 },
 };
 
-- 
1.7.3.1