add debugfs support for powerdebug

Change-Id: I1a2992f01cf10236c25d33feda2b289c2dbbbeb9
Reviewed-on: http://gerrit.lud.stericsson.com/gerrit/8549
Reviewed-by: QATOOLS
Reviewed-by: Vincent GUITTOT <vincent.guittot@stericsson.com>
Tested-by: Vincent GUITTOT <vincent.guittot@stericsson.com>
Reviewed-by: Linus WALLEIJ <linus.walleij@stericsson.com>
Signed-off-by: Vincent Guittot <vincent.guittot@stericsson.com>

2 files changed, 326 insertions, 1 deletions

diff --git a/arch/arm/mach-ux500/clock.c b/arch/arm/mach-ux500/clock.c
index 925937332d7..a4c73fef82e 100644
--- a/arch/arm/mach-ux500/clock.c
+++ b/arch/arm/mach-ux500/clock.c
@@ -11,10 +11,22 @@
 #include <linux/io.h>
 #include <linux/spinlock.h>
 #include <linux/mfd/ab8500/sysctrl.h>
+#ifdef CONFIG_DEBUG_FS
+#include <linux/clk.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+#include <linux/uaccess.h>	/* for copy_from_user */
+#include <linux/kernel.h>
+#endif
+
 #include <mach/prcmu-fw-api.h>
 
 #include "clock.h"
 
+#ifdef CONFIG_DEBUG_FS
+static LIST_HEAD(clk_list);
+#endif
+
 #define PRCC_PCKEN 0x0
 #define PRCC_PCKDIS 0x4
 #define PRCC_KCKEN 0x8
@@ -111,6 +123,16 @@ bus_parent_error:
 	return err;
 }
 
+static struct clk *__clk_get_parent(struct clk *clk)
+{
+	if (clk->parent != NULL)
+		return clk->parent;
+	else if ((clk->bus_parent != NULL))
+		return clk->bus_parent;
+
+	return NULL;
+}
+
 unsigned long __clk_get_rate(struct clk *clk, void *current_lock)
 {
 	unsigned long rate;
@@ -169,6 +191,15 @@ void clk_disable(struct clk *clk)
 }
 EXPORT_SYMBOL(clk_disable);
 
+struct clk *clk_get_parent(struct clk *clk)
+{
+	if (clk == NULL)
+		return ERR_PTR(-EINVAL);
+
+	return __clk_get_parent(clk);
+}
+EXPORT_SYMBOL(clk_get_parent);
+
 unsigned long clk_get_rate(struct clk *clk)
 {
 	if (clk == NULL)
@@ -357,8 +388,14 @@ void clks_register(struct clk_lookup *clks, size_t num)
 {
 	unsigned int i;
 
-	for (i = 0; i < num; i++)
+	for (i = 0; i < num; i++) {
 		clkdev_add(&clks[i]);
+#ifdef CONFIG_DEBUG_FS
+		/* Check that the clock has not been already registered */
+		if (!(clks[i].clk->list.prev != clks[i].clk->list.next))
+			list_add_tail(&clks[i].clk->list, &clk_list);
+#endif
+	}
 }
 
 int __init clk_init(void)
@@ -378,3 +415,287 @@ int __init clk_init(void)
 
 	return 0;
 }
+
+#ifdef CONFIG_DEBUG_FS
+/*
+ *	debugfs support to trace clock tree hierarchy and attributes with
+ *	powerdebug
+ */
+static struct dentry *clk_debugfs_root;
+
+#ifdef CONFIG_DEBUG_FS_WRITE
+static ssize_t enable_dbg_write(struct file *file, const char __user *buf,
+						 size_t size, loff_t *off)
+{
+	struct clk *clk = file->f_dentry->d_inode->i_private;
+
+	clk_enable(clk);
+	return size;
+}
+
+static ssize_t disable_dbg_write(struct file *file, const char __user *buf,
+						  size_t size, loff_t *off)
+{
+	struct clk *clk = file->f_dentry->d_inode->i_private;
+
+	clk_disable(clk);
+	return size;
+}
+
+static ssize_t rate_dbg_write(struct file *file, const char __user *buf,
+					   size_t size, loff_t *off)
+{
+	struct clk *clk = file->f_dentry->d_inode->i_private;
+	char crate[128];
+	unsigned long rate;
+
+	if (size < (sizeof(crate)-1)) {
+		if (copy_from_user(crate, buf, size))
+			return -EFAULT;
+		crate[size] = 0;
+		if (!strict_strtoul(crate, 10, &rate))
+			clk_set_rate(clk, rate);
+		return size;
+	}
+	return -EINVAL;
+}
+
+static ssize_t parent_dbg_write(struct file *file, const char __user *buf,
+						 size_t size, loff_t *off)
+{
+	struct clk *clk = file->f_dentry->d_inode->i_private;
+	char cname[128];
+	struct clk *pclk;
+
+	if (size < (sizeof(cname) - 1)) {
+		if (copy_from_user(cname, buf, size))
+			return -EFAULT;
+		cname[size] = 0;
+		pclk = clk_get_sys(cname, cname);
+		clk_set_parent(clk, pclk);
+		return size;
+	}
+	return -EINVAL;
+}
+#endif
+
+static ssize_t usecount_dbg_read(struct file *file, char __user *buf,
+						  size_t size, loff_t *off)
+{
+	struct clk *clk = file->f_dentry->d_inode->i_private;
+	char cusecount[128];
+	unsigned int len;
+
+	len = sprintf(cusecount, "%u\n", clk->enabled);
+	return simple_read_from_buffer(buf, size, off, cusecount, len);
+}
+
+static ssize_t rate_dbg_read(struct file *file, char __user *buf,
+					  size_t size, loff_t *off)
+{
+	struct clk *clk = file->f_dentry->d_inode->i_private;
+	char crate[128];
+	unsigned int rate;
+	unsigned int len;
+
+	rate = clk_get_rate(clk);
+	len = sprintf(crate, "%u\n", rate);
+	return simple_read_from_buffer(buf, size, off, crate, len);
+}
+
+static ssize_t parent_dbg_read(struct file *file, char __user *buf,
+						size_t size, loff_t *off)
+{
+	struct clk *clk = file->f_dentry->d_inode->i_private;
+	char cname[128];
+	struct clk *pclk;
+	unsigned int len;
+
+	pclk = clk_get_parent(clk);
+	if (pclk)
+		len = sprintf(cname, "%s\n", pclk->name);
+	else
+		len = sprintf(cname, "No parent\n");
+	return simple_read_from_buffer(buf, size, off, cname, len);
+}
+
+#ifdef CONFIG_DEBUG_FS_WRITE
+static const struct file_operations enable_fops = {
+	.write = enable_dbg_write,
+};
+
+static const struct file_operations disable_fops = {
+	.write = disable_dbg_write,
+};
+#endif
+
+static const struct file_operations usecount_fops = {
+	.read = usecount_dbg_read,
+};
+
+static const struct file_operations set_rate_fops = {
+#ifdef CONFIG_DEBUG_FS_WRITE
+	.write = rate_dbg_write,
+#endif
+	.read = rate_dbg_read,
+};
+
+static const struct file_operations set_parent_fops = {
+#ifdef CONFIG_DEBUG_FS_WRITE
+	.write = parent_dbg_write,
+#endif
+	.read = parent_dbg_read,
+};
+
+static struct dentry *clk_debugfs_register_dir(struct clk *c,
+						struct dentry *p_dentry)
+{
+	struct dentry *d, *clk_d, *child, *child_tmp;
+	char s[255];
+	char *p = s;
+
+	if (c->name == NULL)
+		p += sprintf(p, "BUG");
+	else
+		p += sprintf(p, "%s", c->name);
+
+	clk_d = debugfs_create_dir(s, p_dentry);
+	if (!clk_d)
+		return NULL;
+
+	d = debugfs_create_file("usecount", S_IRUGO,
+			clk_d, c, &usecount_fops);
+	if (!d)
+		goto err_out;
+#ifdef CONFIG_DEBUG_FS_WRITE
+	d = debugfs_create_file("enable", S_IWUGO,
+			clk_d, c, &enable_fops);
+	if (!d)
+		goto err_out;
+	d = debugfs_create_file("disable", S_IWUGO,
+			clk_d, c, &disable_fops);
+	if (!d)
+		goto err_out;
+	d = debugfs_create_file("rate", S_IRUGO | S_IWUGO,
+			clk_d, c, &set_rate_fops);
+	if (!d)
+		goto err_out;
+	d = debugfs_create_file("parent",  S_IRUGO | S_IWUGO,
+			clk_d, c, &set_parent_fops);
+	if (!d)
+		goto err_out;
+#else
+	d = debugfs_create_file("rate", S_IRUGO,
+			clk_d, c, &set_rate_fops);
+	if (!d)
+		goto err_out;
+	d = debugfs_create_file("parent",  S_IRUGO,
+			clk_d, c, &set_parent_fops);
+	if (!d)
+		goto err_out;
+#endif
+	/*
+	 * TODO : not currently available in ux500
+	 * d = debugfs_create_x32("flags", S_IRUGO, clk_d, (u32 *)&c->flags);
+	 * if (!d)
+	 *	goto err_out;
+	 */
+
+	return clk_d;
+
+err_out:
+	d = clk_d;
+	list_for_each_entry_safe(child, child_tmp, &d->d_subdirs, d_u.d_child)
+		debugfs_remove(child);
+	debugfs_remove(clk_d);
+	return NULL;
+}
+
+static void clk_debugfs_remove_dir(struct dentry *cdentry)
+{
+	struct dentry *d, *child, *child_tmp;
+
+	d = cdentry;
+	list_for_each_entry_safe(child, child_tmp, &d->d_subdirs, d_u.d_child)
+		debugfs_remove(child);
+	debugfs_remove(cdentry);
+	return ;
+}
+
+
+static int clk_debugfs_register_one(struct clk *c)
+{
+	struct clk *pa = c->parent;
+	struct clk *bpa = c->bus_parent;
+
+	if (!(bpa && !pa)) {
+		c->dent = clk_debugfs_register_dir(c,
+				pa ? pa->dent : clk_debugfs_root);
+		if (!c->dent)
+			return -ENOMEM;
+	}
+
+	if (bpa) {
+		c->dent_bus = clk_debugfs_register_dir(c,
+				bpa->dent_bus ? bpa->dent_bus : bpa->dent);
+		if ((!c->dent_bus) &&  (c->dent)) {
+			clk_debugfs_remove_dir(c->dent);
+			c->dent = NULL;
+			return -ENOMEM;
+		}
+	}
+	return 0;
+}
+
+static int clk_debugfs_register(struct clk *c)
+{
+	int err;
+	struct clk *pa = c->parent;
+	struct clk *bpa = c->bus_parent;
+
+	if (pa && (!pa->dent && !pa->dent_bus)) {
+		err = clk_debugfs_register(pa);
+		if (err)
+			return err;
+	}
+
+	if (bpa && (!bpa->dent && !bpa->dent_bus)) {
+		err = clk_debugfs_register(bpa);
+		if (err)
+			return err;
+	}
+
+	if ((!c->dent) && (!c->dent_bus)) {
+		err = clk_debugfs_register_one(c);
+		if (err)
+			return err;
+	}
+	return 0;
+}
+
+static int __init clk_debugfs_init(void)
+{
+	struct clk *c;
+	struct dentry *d;
+	int err;
+
+	d = debugfs_create_dir("clock", NULL);
+	if (!d)
+		return -ENOMEM;
+	clk_debugfs_root = d;
+
+	list_for_each_entry(c, &clk_list, list) {
+		err = clk_debugfs_register(c);
+		if (err)
+			goto err_out;
+	}
+	return 0;
+err_out:
+	debugfs_remove_recursive(clk_debugfs_root);
+	return err;
+}
+
+late_initcall(clk_debugfs_init);
+#endif /* defined(CONFIG_DEBUG_FS) */
+
+
diff --git a/arch/arm/mach-ux500/clock.h b/arch/arm/mach-ux500/clock.h
index e37e401b883..61d68b50007 100644
--- a/arch/arm/mach-ux500/clock.h
+++ b/arch/arm/mach-ux500/clock.h
@@ -47,6 +47,10 @@ struct clk {
 	struct clk **parents;
 	struct regulator *regulator;
 	struct list_head list;
+#if defined(CONFIG_DEBUG_FS)
+	struct dentry		*dent;	/* For visible tree hierarchy */
+	struct dentry		*dent_bus;	/* For visible tree hierarchy */
+#endif
 };
 
 /**