[PATCH v2] clk: Add hardware-enable column to clk summary

From: Dmitry Osipenko
Date: Sun Nov 15 2020 - 15:45:39 EST


Add "hardware enable" column to the clk summary in order to show actual
hardware enable-state of all clocks. The possible states are "Y/N/?",
where question mark means that state is unknown, i.e. clock isn't a
mux and clk-driver doesn't support is_enabled() callback for this clock.

In conjunction with clk_ignore_unused, this tells us what unused clocks
are left enabled after bootloader. This is also useful a useful aid for
debugging interactions with firmware which changes clock states without
notifying kernel.

Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx>
---

Changelog:

v2: - Renamed "enable state" column to "hardware enable" and changed
reported values to Y/N/?

- Improved commit message.

drivers/clk/clk.c | 15 +++++++++++----
1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index f83dac54ed85..c2cbf3618680 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -2931,7 +2931,14 @@ static void clk_summary_show_one(struct seq_file *s, struct clk_core *c,
else
seq_puts(s, "-----");

- seq_printf(s, " %6d\n", clk_core_get_scaled_duty_cycle(c, 100000));
+ seq_printf(s, " %6d", clk_core_get_scaled_duty_cycle(c, 100000));
+
+ if (c->ops->is_enabled)
+ seq_printf(s, " %9c\n", clk_core_is_enabled(c) ? 'Y' : 'N');
+ else if (!c->ops->enable)
+ seq_printf(s, " %9c\n", 'Y');
+ else
+ seq_printf(s, " %9c\n", '?');
}

static void clk_summary_show_subtree(struct seq_file *s, struct clk_core *c,
@@ -2950,9 +2957,9 @@ static int clk_summary_show(struct seq_file *s, void *data)
struct clk_core *c;
struct hlist_head **lists = (struct hlist_head **)s->private;

- seq_puts(s, " enable prepare protect duty\n");
- seq_puts(s, " clock count count count rate accuracy phase cycle\n");
- seq_puts(s, "---------------------------------------------------------------------------------------------\n");
+ seq_puts(s, " enable prepare protect duty hardware\n");
+ seq_puts(s, " clock count count count rate accuracy phase cycle enable\n");
+ seq_puts(s, "-------------------------------------------------------------------------------------------------------\n");

clk_prepare_lock();

--
2.29.2