[PATCH] clk: debug clock tree
From: Mike Turquette <hidden>
Date: 2012-12-13 16:28:10
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On Wed, Dec 12, 2012 at 7:49 PM, Prashant Gaikwad [off-list ref] wrote:
Adds debug file "clock_tree" in /sys/kernel/debug/clk dir. It helps to view all the clock registered in tree format.
Prashant, Thanks for submitting this. We've been talking about having a single file for representing the tree for some time. Regarding the output format had you considered using a well known format which can be parsed using well known parsing libs? This avoids needing a custom parser just for this one file. JSON springs to mind as something lightweight and well-understood.
quoted hunk ↗ jump to hunk
For example: clock enable_cnt prepare_cnt rate --------------------------------------------------------------------- i2s0_sync 0 0 24000000 spdif_in_sync 0 0 24000000 spdif_mux 0 0 24000000 spdif 0 0 24000000 spdif_doubler 0 0 48000000 spdif_div 0 0 48000000 spdif_2x 0 0 48000000 clk_32k 2 2 32768 blink_override 1 1 32768 blink 1 1 32768 clk_m 2 2 12000000 clk_out_3_mux 0 0 12000000 clk_out_3 0 0 12000000 pll_ref 3 3 12000000 pll_e_mux 0 0 12000000 pll_e 0 0 100000000 cml0 0 0 100000000 cml1 0 0 100000000 pciex 0 0 100000000 pll_d2 0 0 1000000 pll_d2_out0 0 0 500000 pll_d 0 0 1000000 pll_d_out0 0 0 500000 dsib_mux 0 0 500000 dsib 0 0 500000 dsia 0 0 500000 Signed-off-by: Prashant Gaikwad <pgaikwad@nvidia.com> --- drivers/clk/clk.c | 59 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 59 insertions(+), 0 deletions(-)diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index 56e4495e..7daf201 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c@@ -34,6 +34,59 @@ static struct dentry *rootdir; static struct dentry *orphandir; static int inited = 0; +static void clk_tree_show_one(struct seq_file *s, struct clk *c, int level) +{ + if (!c) + return; + + seq_printf(s, "%*s%-*s %-11d %-12d %-10lu", + level * 3 + 1, "", + 30 - level * 3, c->name, + c->enable_count, c->prepare_count, c->rate); + seq_printf(s, "\n"); +} + +static void clk_tree_show_subtree(struct seq_file *s, struct clk *c, int level) +{ + struct clk *child; + struct hlist_node *tmp; + + if (!c) + return; + + clk_tree_show_one(s, c, level); + + hlist_for_each_entry(child, tmp, &c->children, child_node) + clk_tree_show_subtree(s, child, level + 1); +} + +static int clk_tree_show(struct seq_file *s, void *data) +{ + struct clk *c; + struct hlist_node *tmp; + + seq_printf(s, " clock enable_cnt prepare_cnt rate\n"); + seq_printf(s, "---------------------------------------------------------------------\n"); +
If we want this to be machine readable then we can probably drop the heading and line of dashes altogether.
quoted hunk ↗ jump to hunk
+ hlist_for_each_entry(c, tmp, &clk_root_list, child_node) + clk_tree_show_subtree(s, c, 0); + + return 0; +} + + +static int clk_tree_open(struct inode *inode, struct file *file) +{ + return single_open(file, clk_tree_show, inode->i_private); +} + +static const struct file_operations clk_tree_fops = { + .open = clk_tree_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + /* caller must hold prepare_lock */ static int clk_debug_create_one(struct clk *clk, struct dentry *pdentry) {@@ -167,12 +220,18 @@ static int __init clk_debug_init(void) { struct clk *clk; struct hlist_node *tmp; + struct dentry *d; rootdir = debugfs_create_dir("clk", NULL); if (!rootdir) return -ENOMEM; + d = debugfs_create_file("clock_tree", S_IRUGO, rootdir, NULL, + &clk_tree_fops);
I prefer "clk_tree" versus "clock_tree". If we only spell clock one way then users won't have to spend as much time trying to remember specific spellings of the word. This also brings up the question of whether or not we should keep the directory-based debugfs representation around. I personally don't care and I'm happy to deprecate it and remove at a future date if others do not object. However if you have some tooling based around the existing clk debugfs stuff then please speak up and I'll keep both around. Thanks, Mike
+ if (!d)
+ return -ENOMEM;
+
orphandir = debugfs_create_dir("orphans", rootdir);
if (!orphandir)
--
1.7.4.1