linux-clk.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Jerome Brunet <jbrunet@baylibre.com>
To: Stephen Boyd <sboyd@codeaurora.org>,
	Michael Turquette <mturquette@baylibre.com>
Cc: Jerome Brunet <jbrunet@baylibre.com>,
	linux-clk@vger.kernel.org, linux-kernel@vger.kernel.org,
	Russell King <linux@armlinux.org.uk>,
	Linus Walleij <linus.walleij@linaro.org>,
	Quentin Schulz <quentin.schulz@free-electrons.com>,
	Kevin Hilman <khilman@baylibre.com>
Subject: [PATCH v4 04/10] clk: rework calls to round and determine rate callbacks
Date: Sun, 24 Sep 2017 22:00:24 +0200	[thread overview]
Message-ID: <20170924200030.6227-5-jbrunet@baylibre.com> (raw)
In-Reply-To: <20170924200030.6227-1-jbrunet@baylibre.com>

Rework the way the callbacks round_rate() and determine_rate() are called.
The goal is to do this at a single point and make it easier to add
conditions before calling them.

Because of this factorization, rate returned by determine_rate() is also
checked against the min and max rate values

This rework is done to ease the integration of "protected" clock
functionality.

Acked-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Quentin Schulz <quentin.schulz@free-electrons.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
---
 drivers/clk/clk.c | 82 +++++++++++++++++++++++++++++++++++--------------------
 1 file changed, 52 insertions(+), 30 deletions(-)

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 0913688dacb0..0905139a1893 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -833,10 +833,9 @@ static int clk_disable_unused(void)
 }
 late_initcall_sync(clk_disable_unused);
 
-static int clk_core_round_rate_nolock(struct clk_core *core,
-				      struct clk_rate_request *req)
+static int clk_core_determine_round_nolock(struct clk_core *core,
+					   struct clk_rate_request *req)
 {
-	struct clk_core *parent;
 	long rate;
 
 	lockdep_assert_held(&prepare_lock);
@@ -844,15 +843,6 @@ static int clk_core_round_rate_nolock(struct clk_core *core,
 	if (!core)
 		return 0;
 
-	parent = core->parent;
-	if (parent) {
-		req->best_parent_hw = parent->hw;
-		req->best_parent_rate = parent->rate;
-	} else {
-		req->best_parent_hw = NULL;
-		req->best_parent_rate = 0;
-	}
-
 	if (core->ops->determine_rate) {
 		return core->ops->determine_rate(core->hw, req);
 	} else if (core->ops->round_rate) {
@@ -862,15 +852,58 @@ static int clk_core_round_rate_nolock(struct clk_core *core,
 			return rate;
 
 		req->rate = rate;
-	} else if (core->flags & CLK_SET_RATE_PARENT) {
-		return clk_core_round_rate_nolock(parent, req);
 	} else {
-		req->rate = core->rate;
+		return -EINVAL;
 	}
 
 	return 0;
 }
 
+static void clk_core_init_rate_req(struct clk_core * const core,
+				   struct clk_rate_request *req)
+{
+	struct clk_core *parent;
+
+	if (WARN_ON(!core || !req))
+		return;
+
+	parent = core->parent;
+	if (parent) {
+		req->best_parent_hw = parent->hw;
+		req->best_parent_rate = parent->rate;
+	} else {
+		req->best_parent_hw = NULL;
+		req->best_parent_rate = 0;
+	}
+}
+
+static bool clk_core_can_round(struct clk_core * const core)
+{
+	if (core->ops->determine_rate || core->ops->round_rate)
+		return true;
+
+	return false;
+}
+
+static int clk_core_round_rate_nolock(struct clk_core *core,
+				      struct clk_rate_request *req)
+{
+	lockdep_assert_held(&prepare_lock);
+
+	if (!core)
+		return 0;
+
+	clk_core_init_rate_req(core, req);
+
+	if (clk_core_can_round(core))
+		return clk_core_determine_round_nolock(core, req);
+	else if (core->flags & CLK_SET_RATE_PARENT)
+		return clk_core_round_rate_nolock(core->parent, req);
+
+	req->rate = core->rate;
+	return 0;
+}
+
 /**
  * __clk_determine_rate - get the closest rate actually supported by a clock
  * @hw: determine the rate of this clock
@@ -1356,34 +1389,23 @@ static struct clk_core *clk_calc_new_rates(struct clk_core *core,
 	clk_core_get_boundaries(core, &min_rate, &max_rate);
 
 	/* find the closest rate and parent clk/rate */
-	if (core->ops->determine_rate) {
+	if (clk_core_can_round(core)) {
 		struct clk_rate_request req;
 
 		req.rate = rate;
 		req.min_rate = min_rate;
 		req.max_rate = max_rate;
-		if (parent) {
-			req.best_parent_hw = parent->hw;
-			req.best_parent_rate = parent->rate;
-		} else {
-			req.best_parent_hw = NULL;
-			req.best_parent_rate = 0;
-		}
 
-		ret = core->ops->determine_rate(core->hw, &req);
+		clk_core_init_rate_req(core, &req);
+
+		ret = clk_core_determine_round_nolock(core, &req);
 		if (ret < 0)
 			return NULL;
 
 		best_parent_rate = req.best_parent_rate;
 		new_rate = req.rate;
 		parent = req.best_parent_hw ? req.best_parent_hw->core : NULL;
-	} else if (core->ops->round_rate) {
-		ret = core->ops->round_rate(core->hw, rate,
-					    &best_parent_rate);
-		if (ret < 0)
-			return NULL;
 
-		new_rate = ret;
 		if (new_rate < min_rate || new_rate > max_rate)
 			return NULL;
 	} else if (!parent || !(core->flags & CLK_SET_RATE_PARENT)) {
-- 
2.13.5

  parent reply	other threads:[~2017-09-24 20:00 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-09-24 20:00 [PATCH v4 00/10] clk: implement clock rate protection mechanism Jerome Brunet
2017-09-24 20:00 ` [PATCH v4 01/10] clk: fix incorrect usage of ENOSYS Jerome Brunet
2017-09-24 20:00 ` [PATCH v4 02/10] clk: take the prepare lock out of clk_core_set_parent Jerome Brunet
2017-09-24 20:00 ` [PATCH v4 03/10] clk: add clk_core_set_phase_nolock function Jerome Brunet
2017-09-24 20:00 ` Jerome Brunet [this message]
2017-09-24 20:00 ` [PATCH v4 05/10] clk: use round rate to bail out early in set_rate Jerome Brunet
2017-09-24 20:00 ` [PATCH v4 06/10] clk: add clock protection mechanism to clk core Jerome Brunet
2017-09-24 20:00 ` [PATCH v4 07/10] clk: cosmetic changes to clk_summary debugfs entry Jerome Brunet
2017-09-24 20:00 ` [PATCH v4 08/10] clk: fix CLK_SET_RATE_GATE with clock rate protection Jerome Brunet
2017-09-24 20:00 ` [PATCH v4 09/10] clk: add clk_rate_exclusive api Jerome Brunet
2017-10-26  5:26   ` Michael Turquette
2017-10-31 17:29     ` Jerome Brunet
2017-10-31 17:32       ` Michael Turquette
2017-09-24 20:00 ` [PATCH v4 10/10] clk: fix set_rate_range when current rate is out of range Jerome Brunet
2017-10-26  5:29 ` [PATCH v4 00/10] clk: implement clock rate protection mechanism Michael Turquette
2017-11-02  9:04   ` Maxime Ripard
2017-11-02  9:36     ` Jerome Brunet
2017-11-14  9:04       ` Maxime Ripard

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20170924200030.6227-5-jbrunet@baylibre.com \
    --to=jbrunet@baylibre.com \
    --cc=khilman@baylibre.com \
    --cc=linus.walleij@linaro.org \
    --cc=linux-clk@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux@armlinux.org.uk \
    --cc=mturquette@baylibre.com \
    --cc=quentin.schulz@free-electrons.com \
    --cc=sboyd@codeaurora.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).