* [PATCH v5 00/11] clk: Improve clock range handling
@ 2022-02-22 13:18 ` Maxime Ripard
0 siblings, 0 replies; 26+ messages in thread
From: Maxime Ripard @ 2022-02-22 13:18 UTC (permalink / raw)
To: Mike Turquette, Stephen Boyd
Cc: dri-devel, linux-clk, Dave Stevenson, Phil Elwell, Tim Gover,
Dom Cobley, Maxime Ripard
Hi,
This is a follow-up of the discussion here:
https://lore.kernel.org/linux-clk/20210319150355.xzw7ikwdaga2dwhv@gilmour/
and here:
https://lore.kernel.org/all/20210914093515.260031-1-maxime@cerno.tech/
While the initial proposal implemented a new API to temporarily raise and lower
clock rates based on consumer workloads, Stephen suggested an
alternative approach implemented here.
The main issue that needed to be addressed in our case was that in a
situation where we would have multiple calls to clk_set_rate_range, we
would end up with a clock at the maximum of the minimums being set. This
would be expected, but the issue was that if one of the users was to
relax or drop its requirements, the rate would be left unchanged, even
though the ideal rate would have changed.
So something like
clk_set_rate(user1_clk, 1000);
clk_set_min_rate(user1_clk, 2000);
clk_set_min_rate(user2_clk, 3000);
clk_set_min_rate(user2_clk, 1000);
Would leave the clock running at 3000Hz, while the minimum would now be
2000Hz.
This was mostly due to the fact that the core only triggers a rate
change in clk_set_rate_range() if the current rate is outside of the
boundaries, but not if it's within the new boundaries.
That series changes that and will trigger a rate change on every call,
with the former rate being tried again. This way, providers have a
chance to follow whatever policy they see fit for a given clock each
time the boundaries change.
This series also implements some kunit tests, first to test a few rate
related functions in the CCF, and then extends it to make sure that
behaviour has some test coverage.
Let me know what you think
Maxime
Changes from v4:
- Rename the test file
- Move all the tests to the first patch, and fix them up as fixes are done
- Improved the test conditions
- Added more tests
- Improved commit messages
- Fixed a regression where two disjoints clock ranges would now be accepted
Changes from v3:
- Renamed the test file and Kconfig option
- Add option to .kunitconfig
- Switch to kunit_kzalloc
- Use KUNIT_EXPECT_* instead of KUNIT_ASSERT_* where relevant
- Test directly relevant calls instead of going through a temporary variable
- Switch to more precise KUNIT_ASSERT_* macros where relevant
Changes from v2:
- Rebased on current next
- Rewrote the whole thing according to Stephen reviews
- Implemented some kunit tests
Changes from v1:
- Return NULL in clk_request_start if clk pointer is NULL
- Test for clk_req pointer in clk_request_done
- Add another user in vc4
- Rebased on top of v5.15-rc1
Maxime Ripard (11):
clk: Introduce Kunit Tests for the framework
clk: Enforce that disjoints limits are invalid
clk: Always clamp the rounded rate
clk: Use clamp instead of open-coding our own
clk: Always set the rate on clk_set_range_rate
clk: Add clk_drop_range
clk: bcm: rpi: Add variant structure
clk: bcm: rpi: Set a default minimum rate
clk: bcm: rpi: Run some clocks at the minimum rate allowed
drm/vc4: Add logging and comments
drm/vc4: hdmi: Remove clock rate initialization
drivers/clk/.kunitconfig | 1 +
drivers/clk/Kconfig | 7 +
drivers/clk/Makefile | 1 +
drivers/clk/bcm/clk-raspberrypi.c | 125 ++++-
drivers/clk/clk.c | 73 ++-
drivers/clk/clk_test.c | 790 ++++++++++++++++++++++++++++++
drivers/gpu/drm/vc4/vc4_hdmi.c | 13 -
drivers/gpu/drm/vc4/vc4_kms.c | 11 +
include/linux/clk.h | 11 +
9 files changed, 978 insertions(+), 54 deletions(-)
create mode 100644 drivers/clk/clk_test.c
--
2.35.1
^ permalink raw reply [flat|nested] 26+ messages in thread
* [PATCH v5 00/11] clk: Improve clock range handling
@ 2022-02-22 13:18 ` Maxime Ripard
0 siblings, 0 replies; 26+ messages in thread
From: Maxime Ripard @ 2022-02-22 13:18 UTC (permalink / raw)
To: Mike Turquette, Stephen Boyd
Cc: Dom Cobley, Tim Gover, Dave Stevenson, dri-devel, linux-clk,
Maxime Ripard, Phil Elwell
Hi,
This is a follow-up of the discussion here:
https://lore.kernel.org/linux-clk/20210319150355.xzw7ikwdaga2dwhv@gilmour/
and here:
https://lore.kernel.org/all/20210914093515.260031-1-maxime@cerno.tech/
While the initial proposal implemented a new API to temporarily raise and lower
clock rates based on consumer workloads, Stephen suggested an
alternative approach implemented here.
The main issue that needed to be addressed in our case was that in a
situation where we would have multiple calls to clk_set_rate_range, we
would end up with a clock at the maximum of the minimums being set. This
would be expected, but the issue was that if one of the users was to
relax or drop its requirements, the rate would be left unchanged, even
though the ideal rate would have changed.
So something like
clk_set_rate(user1_clk, 1000);
clk_set_min_rate(user1_clk, 2000);
clk_set_min_rate(user2_clk, 3000);
clk_set_min_rate(user2_clk, 1000);
Would leave the clock running at 3000Hz, while the minimum would now be
2000Hz.
This was mostly due to the fact that the core only triggers a rate
change in clk_set_rate_range() if the current rate is outside of the
boundaries, but not if it's within the new boundaries.
That series changes that and will trigger a rate change on every call,
with the former rate being tried again. This way, providers have a
chance to follow whatever policy they see fit for a given clock each
time the boundaries change.
This series also implements some kunit tests, first to test a few rate
related functions in the CCF, and then extends it to make sure that
behaviour has some test coverage.
Let me know what you think
Maxime
Changes from v4:
- Rename the test file
- Move all the tests to the first patch, and fix them up as fixes are done
- Improved the test conditions
- Added more tests
- Improved commit messages
- Fixed a regression where two disjoints clock ranges would now be accepted
Changes from v3:
- Renamed the test file and Kconfig option
- Add option to .kunitconfig
- Switch to kunit_kzalloc
- Use KUNIT_EXPECT_* instead of KUNIT_ASSERT_* where relevant
- Test directly relevant calls instead of going through a temporary variable
- Switch to more precise KUNIT_ASSERT_* macros where relevant
Changes from v2:
- Rebased on current next
- Rewrote the whole thing according to Stephen reviews
- Implemented some kunit tests
Changes from v1:
- Return NULL in clk_request_start if clk pointer is NULL
- Test for clk_req pointer in clk_request_done
- Add another user in vc4
- Rebased on top of v5.15-rc1
Maxime Ripard (11):
clk: Introduce Kunit Tests for the framework
clk: Enforce that disjoints limits are invalid
clk: Always clamp the rounded rate
clk: Use clamp instead of open-coding our own
clk: Always set the rate on clk_set_range_rate
clk: Add clk_drop_range
clk: bcm: rpi: Add variant structure
clk: bcm: rpi: Set a default minimum rate
clk: bcm: rpi: Run some clocks at the minimum rate allowed
drm/vc4: Add logging and comments
drm/vc4: hdmi: Remove clock rate initialization
drivers/clk/.kunitconfig | 1 +
drivers/clk/Kconfig | 7 +
drivers/clk/Makefile | 1 +
drivers/clk/bcm/clk-raspberrypi.c | 125 ++++-
drivers/clk/clk.c | 73 ++-
drivers/clk/clk_test.c | 790 ++++++++++++++++++++++++++++++
drivers/gpu/drm/vc4/vc4_hdmi.c | 13 -
drivers/gpu/drm/vc4/vc4_kms.c | 11 +
include/linux/clk.h | 11 +
9 files changed, 978 insertions(+), 54 deletions(-)
create mode 100644 drivers/clk/clk_test.c
--
2.35.1
^ permalink raw reply [flat|nested] 26+ messages in thread
* [PATCH v5 01/11] clk: Introduce Kunit Tests for the framework
2022-02-22 13:18 ` Maxime Ripard
@ 2022-02-22 13:18 ` Maxime Ripard
-1 siblings, 0 replies; 26+ messages in thread
From: Maxime Ripard @ 2022-02-22 13:18 UTC (permalink / raw)
To: Mike Turquette, Stephen Boyd
Cc: dri-devel, linux-clk, Dave Stevenson, Phil Elwell, Tim Gover,
Dom Cobley, Maxime Ripard, kunit-dev
Let's test various parts of the rate-related clock API with the kunit
testing framework.
Cc: kunit-dev@googlegroups.com
Suggested-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
---
drivers/clk/.kunitconfig | 1 +
drivers/clk/Kconfig | 7 +
drivers/clk/Makefile | 1 +
drivers/clk/clk_test.c | 786 +++++++++++++++++++++++++++++++++++++++
4 files changed, 795 insertions(+)
create mode 100644 drivers/clk/clk_test.c
diff --git a/drivers/clk/.kunitconfig b/drivers/clk/.kunitconfig
index 3754fdb9485a..cdbc7d7deba9 100644
--- a/drivers/clk/.kunitconfig
+++ b/drivers/clk/.kunitconfig
@@ -1,3 +1,4 @@
CONFIG_KUNIT=y
CONFIG_COMMON_CLK=y
+CONFIG_CLK_KUNIT_TEST=y
CONFIG_CLK_GATE_KUNIT_TEST=y
diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig
index 3cdf33470a75..2ef6eca297ff 100644
--- a/drivers/clk/Kconfig
+++ b/drivers/clk/Kconfig
@@ -429,6 +429,13 @@ source "drivers/clk/xilinx/Kconfig"
source "drivers/clk/zynqmp/Kconfig"
# Kunit test cases
+config CLK_KUNIT_TEST
+ tristate "Basic Clock Framework Kunit Tests" if !KUNIT_ALL_TESTS
+ depends on KUNIT
+ default KUNIT_ALL_TESTS
+ help
+ Kunit tests for the common clock framework.
+
config CLK_GATE_KUNIT_TEST
tristate "Basic gate type Kunit test" if !KUNIT_ALL_TESTS
depends on KUNIT
diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index 6a98291350b6..8f9b1daba411 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -2,6 +2,7 @@
# common clock types
obj-$(CONFIG_HAVE_CLK) += clk-devres.o clk-bulk.o clkdev.o
obj-$(CONFIG_COMMON_CLK) += clk.o
+obj-$(CONFIG_CLK_KUNIT_TEST) += clk_test.o
obj-$(CONFIG_COMMON_CLK) += clk-divider.o
obj-$(CONFIG_COMMON_CLK) += clk-fixed-factor.o
obj-$(CONFIG_COMMON_CLK) += clk-fixed-rate.o
diff --git a/drivers/clk/clk_test.c b/drivers/clk/clk_test.c
new file mode 100644
index 000000000000..8ddfd3b195e1
--- /dev/null
+++ b/drivers/clk/clk_test.c
@@ -0,0 +1,786 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Kunit test for clk rate management
+ */
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/slab.h>
+
+/* Needed for clk_hw_create_clk() */
+#include "clk.h"
+
+#include <kunit/test.h>
+
+#define DUMMY_CLOCK_INIT_RATE (42 * 1000 * 1000)
+#define DUMMY_CLOCK_RATE_1 (142 * 1000 * 1000)
+#define DUMMY_CLOCK_RATE_2 (242 * 1000 * 1000)
+
+struct clk_dummy_context {
+ struct clk_hw hw;
+ unsigned long rate;
+};
+
+static unsigned long clk_dummy_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct clk_dummy_context *ctx =
+ container_of(hw, struct clk_dummy_context, hw);
+
+ return ctx->rate;
+}
+
+static int clk_dummy_determine_rate(struct clk_hw *hw,
+ struct clk_rate_request *req)
+{
+ /* Just return the same rate without modifying it */
+ return 0;
+}
+
+static int clk_dummy_maximize_rate(struct clk_hw *hw,
+ struct clk_rate_request *req)
+{
+ /*
+ * If there's a maximum set, always run the clock at the maximum
+ * allowed.
+ */
+ if (req->max_rate < ULONG_MAX)
+ req->rate = req->max_rate;
+
+ return 0;
+}
+
+static int clk_dummy_minimize_rate(struct clk_hw *hw,
+ struct clk_rate_request *req)
+{
+ /*
+ * If there's a minimum set, always run the clock at the minimum
+ * allowed.
+ */
+ if (req->min_rate > 0)
+ req->rate = req->min_rate;
+
+ return 0;
+}
+
+static int clk_dummy_set_rate(struct clk_hw *hw,
+ unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct clk_dummy_context *ctx =
+ container_of(hw, struct clk_dummy_context, hw);
+
+ ctx->rate = rate;
+ return 0;
+}
+
+static const struct clk_ops clk_dummy_rate_ops = {
+ .recalc_rate = clk_dummy_recalc_rate,
+ .determine_rate = clk_dummy_determine_rate,
+ .set_rate = clk_dummy_set_rate,
+};
+
+static const struct clk_ops clk_dummy_maximize_rate_ops = {
+ .recalc_rate = clk_dummy_recalc_rate,
+ .determine_rate = clk_dummy_maximize_rate,
+ .set_rate = clk_dummy_set_rate,
+};
+
+static const struct clk_ops clk_dummy_minimize_rate_ops = {
+ .recalc_rate = clk_dummy_recalc_rate,
+ .determine_rate = clk_dummy_minimize_rate,
+ .set_rate = clk_dummy_set_rate,
+};
+
+static int clk_test_init_with_ops(struct kunit *test, const struct clk_ops *ops)
+{
+ struct clk_dummy_context *ctx;
+ struct clk_init_data init = { };
+ int ret;
+
+ ctx = kunit_kzalloc(test, sizeof(*ctx), GFP_KERNEL);
+ if (!ctx)
+ return -ENOMEM;
+ ctx->rate = DUMMY_CLOCK_INIT_RATE;
+ test->priv = ctx;
+
+ init.name = "test_dummy_rate";
+ init.ops = ops;
+ ctx->hw.init = &init;
+
+ ret = clk_hw_register(NULL, &ctx->hw);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+static int clk_test_init(struct kunit *test)
+{
+ return clk_test_init_with_ops(test, &clk_dummy_rate_ops);
+}
+
+static int clk_maximize_test_init(struct kunit *test)
+{
+ return clk_test_init_with_ops(test, &clk_dummy_maximize_rate_ops);
+}
+
+static int clk_minimize_test_init(struct kunit *test)
+{
+ return clk_test_init_with_ops(test, &clk_dummy_minimize_rate_ops);
+}
+
+static void clk_test_exit(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+
+ clk_hw_unregister(&ctx->hw);
+}
+
+/*
+ * Test that the actual rate matches what is returned by clk_get_rate()
+ */
+static void clk_test_get_rate(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *clk = hw->clk;
+ unsigned long rate;
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_TRUE(test, rate > 0);
+ KUNIT_EXPECT_EQ(test, rate, ctx->rate);
+}
+
+/*
+ * Test that, after a call to clk_set_rate(), the rate returned by
+ * clk_get_rate() matches.
+ *
+ * This assumes that clk_ops.determine_rate or clk_ops.round_rate won't
+ * modify the requested rate, which is our case in clk_dummy_rate_ops.
+ */
+static void clk_test_set_get_rate(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *clk = hw->clk;
+ unsigned long rate;
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate(clk, DUMMY_CLOCK_RATE_1),
+ 0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_1);
+}
+
+/*
+ * Test that, after several calls to clk_set_rate(), the rate returned
+ * by clk_get_rate() matches the last one.
+ *
+ * This assumes that clk_ops.determine_rate or clk_ops.round_rate won't
+ * modify the requested rate, which is our case in clk_dummy_rate_ops.
+ */
+static void clk_test_set_set_get_rate(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *clk = hw->clk;
+ unsigned long rate;
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate(clk, DUMMY_CLOCK_RATE_1),
+ 0);
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate(clk, DUMMY_CLOCK_RATE_2),
+ 0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_2);
+}
+
+/*
+ * Test that clk_round_rate and clk_set_rate are consitent and will
+ * return the same frequency.
+ */
+static void clk_test_round_set_get_rate(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *clk = hw->clk;
+ unsigned long rounded_rate, set_rate;
+
+ rounded_rate = clk_round_rate(clk, DUMMY_CLOCK_RATE_1);
+ KUNIT_ASSERT_GT(test, rounded_rate, 0);
+ KUNIT_EXPECT_EQ(test, rounded_rate, DUMMY_CLOCK_RATE_1);
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate(clk, DUMMY_CLOCK_RATE_1),
+ 0);
+
+ set_rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, set_rate, 0);
+ KUNIT_EXPECT_EQ(test, rounded_rate, set_rate);
+}
+
+static struct kunit_case clk_test_cases[] = {
+ KUNIT_CASE(clk_test_get_rate),
+ KUNIT_CASE(clk_test_set_get_rate),
+ KUNIT_CASE(clk_test_set_set_get_rate),
+ KUNIT_CASE(clk_test_round_set_get_rate),
+ {}
+};
+
+static struct kunit_suite clk_test_suite = {
+ .name = "clk-test",
+ .init = clk_test_init,
+ .exit = clk_test_exit,
+ .test_cases = clk_test_cases,
+};
+
+/*
+ * Test that clk_set_rate_range won't return an error for a valid range.
+ */
+static void clk_range_test_set_range(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *clk = hw->clk;
+ unsigned long rate;
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(clk,
+ DUMMY_CLOCK_RATE_1,
+ DUMMY_CLOCK_RATE_2),
+ 0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_GE(test, rate, DUMMY_CLOCK_RATE_1);
+ KUNIT_EXPECT_LE(test, rate, DUMMY_CLOCK_RATE_2);
+}
+
+/*
+ * Test that calling clk_set_rate_range with a minimum rate higher than
+ * the maximum rate returns an error.
+ */
+static void clk_range_test_set_range_invalid(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *clk = hw->clk;
+
+ KUNIT_EXPECT_LT(test,
+ clk_set_rate_range(clk,
+ DUMMY_CLOCK_RATE_1 + 1000,
+ DUMMY_CLOCK_RATE_1),
+ 0);
+}
+
+/*
+ * Test that users can't set multiple, disjoints, range that would be
+ * impossible to meet.
+ */
+static void clk_range_test_multiple_disjoints_range(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *user1, *user2;
+
+ user1 = clk_hw_create_clk(NULL, hw, NULL, NULL);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, user1);
+
+ user2 = clk_hw_create_clk(NULL, hw, NULL, NULL);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, user2);
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(user1, 1000, 2000),
+ 0);
+
+ KUNIT_EXPECT_LT(test,
+ clk_set_rate_range(user2, 3000, 4000),
+ 0);
+
+ clk_put(user2);
+ clk_put(user1);
+}
+
+/*
+ * Test that if our clock has some boundaries and we try to round a rate
+ * lower than the minimum, the returned rate won't be affected by the
+ * boundaries.
+ */
+static void clk_range_test_set_range_round_rate_lower(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *clk = hw->clk;
+ long rate;
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(clk,
+ DUMMY_CLOCK_RATE_1,
+ DUMMY_CLOCK_RATE_2),
+ 0);
+
+ rate = clk_round_rate(clk, DUMMY_CLOCK_RATE_1 - 1000);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_1 - 1000);
+}
+
+/*
+ * Test that if our clock has some boundaries and we try to set a rate
+ * lower than the minimum, we'll get an error.
+ */
+static void clk_range_test_set_range_set_rate_lower(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *clk = hw->clk;
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(clk,
+ DUMMY_CLOCK_RATE_1,
+ DUMMY_CLOCK_RATE_2),
+ 0);
+
+ KUNIT_ASSERT_LT(test,
+ clk_set_rate(clk, DUMMY_CLOCK_RATE_1 - 1000),
+ 0);
+}
+
+/*
+ * Test that if our clock has some boundaries and we try to round and
+ * set a rate lower than the minimum, the values won't be consistent
+ * between clk_round_rate() and clk_set_rate().
+ */
+static void clk_range_test_set_range_set_round_rate_consistent_lower(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *clk = hw->clk;
+ long rounded;
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(clk,
+ DUMMY_CLOCK_RATE_1,
+ DUMMY_CLOCK_RATE_2),
+ 0);
+
+ rounded = clk_round_rate(clk, DUMMY_CLOCK_RATE_1 - 1000);
+ KUNIT_ASSERT_GT(test, rounded, 0);
+
+ KUNIT_EXPECT_LT(test,
+ clk_set_rate(clk, DUMMY_CLOCK_RATE_1 - 1000),
+ 0);
+
+ KUNIT_EXPECT_NE(test, rounded, clk_get_rate(clk));
+}
+
+/*
+ * Test that if our clock has some boundaries and we try to round a rate
+ * higher than the maximum, the returned rate won't be affected by the
+ * boundaries.
+ */
+static void clk_range_test_set_range_round_rate_higher(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *clk = hw->clk;
+ long rate;
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(clk,
+ DUMMY_CLOCK_RATE_1,
+ DUMMY_CLOCK_RATE_2),
+ 0);
+
+ rate = clk_round_rate(clk, DUMMY_CLOCK_RATE_2 + 1000);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_2 + 1000);
+}
+
+/*
+ * Test that if our clock has some boundaries and we try to set a rate
+ * lower than the maximum, we'll get an error.
+ */
+static void clk_range_test_set_range_set_rate_higher(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *clk = hw->clk;
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(clk,
+ DUMMY_CLOCK_RATE_1,
+ DUMMY_CLOCK_RATE_2),
+ 0);
+
+ KUNIT_ASSERT_LT(test,
+ clk_set_rate(clk, DUMMY_CLOCK_RATE_2 + 1000),
+ 0);
+}
+
+/*
+ * Test that if our clock has some boundaries and we try to round and
+ * set a rate higher than the maximum, the values won't be consistent
+ * between clk_round_rate() and clk_set_rate().
+ */
+static void clk_range_test_set_range_set_round_rate_consistent_higher(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *clk = hw->clk;
+ long rounded;
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(clk,
+ DUMMY_CLOCK_RATE_1,
+ DUMMY_CLOCK_RATE_2),
+ 0);
+
+ rounded = clk_round_rate(clk, DUMMY_CLOCK_RATE_2 + 1000);
+ KUNIT_ASSERT_GT(test, rounded, 0);
+
+ KUNIT_EXPECT_LT(test,
+ clk_set_rate(clk, DUMMY_CLOCK_RATE_2 + 1000),
+ 0);
+
+ KUNIT_EXPECT_NE(test, rounded, clk_get_rate(clk));
+}
+
+/*
+ * Test that if our clock has a rate lower than the minimum set by a
+ * call to clk_set_rate_range(), the rate will be raised to match the
+ * new minimum.
+ *
+ * This assumes that clk_ops.determine_rate or clk_ops.round_rate won't
+ * modify the requested rate, which is our case in clk_dummy_rate_ops.
+ */
+static void clk_range_test_set_range_get_rate_raised(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *clk = hw->clk;
+ unsigned long rate;
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate(clk, DUMMY_CLOCK_RATE_1 - 1000),
+ 0);
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(clk,
+ DUMMY_CLOCK_RATE_1,
+ DUMMY_CLOCK_RATE_2),
+ 0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_1);
+}
+
+/*
+ * Test that if our clock has a rate higher than the maximum set by a
+ * call to clk_set_rate_range(), the rate will be lowered to match the
+ * new maximum.
+ *
+ * This assumes that clk_ops.determine_rate or clk_ops.round_rate won't
+ * modify the requested rate, which is our case in clk_dummy_rate_ops.
+ */
+static void clk_range_test_set_range_get_rate_lowered(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *clk = hw->clk;
+ unsigned long rate;
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate(clk, DUMMY_CLOCK_RATE_2 + 1000),
+ 0);
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(clk,
+ DUMMY_CLOCK_RATE_1,
+ DUMMY_CLOCK_RATE_2),
+ 0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_2);
+}
+
+static struct kunit_case clk_range_test_cases[] = {
+ KUNIT_CASE(clk_range_test_set_range),
+ KUNIT_CASE(clk_range_test_set_range_invalid),
+ KUNIT_CASE(clk_range_test_multiple_disjoints_range),
+ KUNIT_CASE(clk_range_test_set_range_round_rate_lower),
+ KUNIT_CASE(clk_range_test_set_range_set_rate_lower),
+ KUNIT_CASE(clk_range_test_set_range_set_round_rate_consistent_lower),
+ KUNIT_CASE(clk_range_test_set_range_round_rate_higher),
+ KUNIT_CASE(clk_range_test_set_range_set_rate_higher),
+ KUNIT_CASE(clk_range_test_set_range_set_round_rate_consistent_higher),
+ KUNIT_CASE(clk_range_test_set_range_get_rate_raised),
+ KUNIT_CASE(clk_range_test_set_range_get_rate_lowered),
+ {}
+};
+
+static struct kunit_suite clk_range_test_suite = {
+ .name = "clk-range-test",
+ .init = clk_test_init,
+ .exit = clk_test_exit,
+ .test_cases = clk_range_test_cases,
+};
+
+/*
+ * Test that if:
+ * - we have several subsequent calls to clk_set_rate_range();
+ * - and we have a round_rate ops that always return the maximum
+ * frequency allowed;
+ *
+ * The clock will run at the minimum of all maximum boundaries
+ * requested, even if those boundaries aren't there anymore.
+ */
+static void clk_range_test_set_range_rate_maximized(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *clk = hw->clk;
+ unsigned long rate;
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate(clk, DUMMY_CLOCK_RATE_2 + 1000),
+ 0);
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(clk,
+ DUMMY_CLOCK_RATE_1,
+ DUMMY_CLOCK_RATE_2),
+ 0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_2);
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(clk,
+ DUMMY_CLOCK_RATE_1,
+ DUMMY_CLOCK_RATE_2 - 1000),
+ 0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_2 - 1000);
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(clk,
+ DUMMY_CLOCK_RATE_1,
+ DUMMY_CLOCK_RATE_2),
+ 0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_2 - 1000);
+}
+
+/*
+ * Test that if:
+ * - we have several subsequent calls to clk_set_rate_range(), across
+ * multiple users;
+ * - and we have a round_rate ops that always return the maximum
+ * frequency allowed;
+ *
+ * The clock will run at the minimum of all maximum boundaries
+ * requested, even if those boundaries aren't there anymore.
+ */
+static void clk_range_test_multiple_set_range_rate_maximized(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *clk = hw->clk;
+ struct clk *user1, *user2;
+ unsigned long rate;
+
+ user1 = clk_hw_create_clk(NULL, hw, NULL, NULL);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, user1);
+
+ user2 = clk_hw_create_clk(NULL, hw, NULL, NULL);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, user2);
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate(clk, DUMMY_CLOCK_RATE_2 + 1000),
+ 0);
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(user1,
+ 0,
+ DUMMY_CLOCK_RATE_2),
+ 0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_2);
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(user2,
+ 0,
+ DUMMY_CLOCK_RATE_1),
+ 0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_1);
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(user2, 0, ULONG_MAX),
+ 0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_1);
+
+ clk_put(user2);
+ clk_put(user1);
+}
+
+static struct kunit_case clk_range_maximize_test_cases[] = {
+ KUNIT_CASE(clk_range_test_set_range_rate_maximized),
+ KUNIT_CASE(clk_range_test_multiple_set_range_rate_maximized),
+ {}
+};
+
+static struct kunit_suite clk_range_maximize_test_suite = {
+ .name = "clk-range-maximize-test",
+ .init = clk_maximize_test_init,
+ .exit = clk_test_exit,
+ .test_cases = clk_range_maximize_test_cases,
+};
+
+/*
+ * Test that if:
+ * - we have several subsequent calls to clk_set_rate_range()
+ * - and we have a round_rate ops that always return the minimum
+ * frequency allowed;
+ *
+ * The clock will run at the maximum of all minimum boundaries
+ * requested, even if those boundaries aren't there anymore.
+*/
+static void clk_range_test_set_range_rate_minimized(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *clk = hw->clk;
+ unsigned long rate;
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate(clk, DUMMY_CLOCK_RATE_1 - 1000),
+ 0);
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(clk,
+ DUMMY_CLOCK_RATE_1,
+ DUMMY_CLOCK_RATE_2),
+ 0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_1);
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(clk,
+ DUMMY_CLOCK_RATE_1 + 1000,
+ DUMMY_CLOCK_RATE_2),
+ 0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_1 + 1000);
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(clk,
+ DUMMY_CLOCK_RATE_1,
+ DUMMY_CLOCK_RATE_2),
+ 0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_1 + 1000);
+}
+
+/*
+ * Test that if:
+ * - we have several subsequent calls to clk_set_rate_range(), across
+ * multiple users;
+ * - and we have a round_rate ops that always return the minimum
+ * frequency allowed;
+ *
+ * The clock will run at the maximum of all minimum boundaries
+ * requested, even if those boundaries aren't there anymore.
+*/
+static void clk_range_test_multiple_set_range_rate_minimized(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *clk = hw->clk;
+ struct clk *user1, *user2;
+ unsigned long rate;
+
+ user1 = clk_hw_create_clk(NULL, hw, NULL, NULL);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, user1);
+
+ user2 = clk_hw_create_clk(NULL, hw, NULL, NULL);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, user2);
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(user1,
+ DUMMY_CLOCK_RATE_1,
+ ULONG_MAX),
+ 0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_1);
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(user2,
+ DUMMY_CLOCK_RATE_2,
+ ULONG_MAX),
+ 0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_2);
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(user2, 0, ULONG_MAX),
+ 0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_2);
+
+ clk_put(user2);
+ clk_put(user1);
+}
+
+static struct kunit_case clk_range_minimize_test_cases[] = {
+ KUNIT_CASE(clk_range_test_set_range_rate_minimized),
+ KUNIT_CASE(clk_range_test_multiple_set_range_rate_minimized),
+ {}
+};
+
+static struct kunit_suite clk_range_minimize_test_suite = {
+ .name = "clk-range-minimize-test",
+ .init = clk_minimize_test_init,
+ .exit = clk_test_exit,
+ .test_cases = clk_range_minimize_test_cases,
+};
+
+kunit_test_suites(
+ &clk_test_suite,
+ &clk_range_test_suite,
+ &clk_range_maximize_test_suite,
+ &clk_range_minimize_test_suite
+);
+MODULE_LICENSE("GPL v2");
--
2.35.1
^ permalink raw reply related [flat|nested] 26+ messages in thread
* [PATCH v5 01/11] clk: Introduce Kunit Tests for the framework
@ 2022-02-22 13:18 ` Maxime Ripard
0 siblings, 0 replies; 26+ messages in thread
From: Maxime Ripard @ 2022-02-22 13:18 UTC (permalink / raw)
To: Mike Turquette, Stephen Boyd
Cc: Dom Cobley, Tim Gover, Dave Stevenson, dri-devel, linux-clk,
Maxime Ripard, Phil Elwell, kunit-dev
Let's test various parts of the rate-related clock API with the kunit
testing framework.
Cc: kunit-dev@googlegroups.com
Suggested-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
---
drivers/clk/.kunitconfig | 1 +
drivers/clk/Kconfig | 7 +
drivers/clk/Makefile | 1 +
drivers/clk/clk_test.c | 786 +++++++++++++++++++++++++++++++++++++++
4 files changed, 795 insertions(+)
create mode 100644 drivers/clk/clk_test.c
diff --git a/drivers/clk/.kunitconfig b/drivers/clk/.kunitconfig
index 3754fdb9485a..cdbc7d7deba9 100644
--- a/drivers/clk/.kunitconfig
+++ b/drivers/clk/.kunitconfig
@@ -1,3 +1,4 @@
CONFIG_KUNIT=y
CONFIG_COMMON_CLK=y
+CONFIG_CLK_KUNIT_TEST=y
CONFIG_CLK_GATE_KUNIT_TEST=y
diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig
index 3cdf33470a75..2ef6eca297ff 100644
--- a/drivers/clk/Kconfig
+++ b/drivers/clk/Kconfig
@@ -429,6 +429,13 @@ source "drivers/clk/xilinx/Kconfig"
source "drivers/clk/zynqmp/Kconfig"
# Kunit test cases
+config CLK_KUNIT_TEST
+ tristate "Basic Clock Framework Kunit Tests" if !KUNIT_ALL_TESTS
+ depends on KUNIT
+ default KUNIT_ALL_TESTS
+ help
+ Kunit tests for the common clock framework.
+
config CLK_GATE_KUNIT_TEST
tristate "Basic gate type Kunit test" if !KUNIT_ALL_TESTS
depends on KUNIT
diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index 6a98291350b6..8f9b1daba411 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -2,6 +2,7 @@
# common clock types
obj-$(CONFIG_HAVE_CLK) += clk-devres.o clk-bulk.o clkdev.o
obj-$(CONFIG_COMMON_CLK) += clk.o
+obj-$(CONFIG_CLK_KUNIT_TEST) += clk_test.o
obj-$(CONFIG_COMMON_CLK) += clk-divider.o
obj-$(CONFIG_COMMON_CLK) += clk-fixed-factor.o
obj-$(CONFIG_COMMON_CLK) += clk-fixed-rate.o
diff --git a/drivers/clk/clk_test.c b/drivers/clk/clk_test.c
new file mode 100644
index 000000000000..8ddfd3b195e1
--- /dev/null
+++ b/drivers/clk/clk_test.c
@@ -0,0 +1,786 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Kunit test for clk rate management
+ */
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/slab.h>
+
+/* Needed for clk_hw_create_clk() */
+#include "clk.h"
+
+#include <kunit/test.h>
+
+#define DUMMY_CLOCK_INIT_RATE (42 * 1000 * 1000)
+#define DUMMY_CLOCK_RATE_1 (142 * 1000 * 1000)
+#define DUMMY_CLOCK_RATE_2 (242 * 1000 * 1000)
+
+struct clk_dummy_context {
+ struct clk_hw hw;
+ unsigned long rate;
+};
+
+static unsigned long clk_dummy_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct clk_dummy_context *ctx =
+ container_of(hw, struct clk_dummy_context, hw);
+
+ return ctx->rate;
+}
+
+static int clk_dummy_determine_rate(struct clk_hw *hw,
+ struct clk_rate_request *req)
+{
+ /* Just return the same rate without modifying it */
+ return 0;
+}
+
+static int clk_dummy_maximize_rate(struct clk_hw *hw,
+ struct clk_rate_request *req)
+{
+ /*
+ * If there's a maximum set, always run the clock at the maximum
+ * allowed.
+ */
+ if (req->max_rate < ULONG_MAX)
+ req->rate = req->max_rate;
+
+ return 0;
+}
+
+static int clk_dummy_minimize_rate(struct clk_hw *hw,
+ struct clk_rate_request *req)
+{
+ /*
+ * If there's a minimum set, always run the clock at the minimum
+ * allowed.
+ */
+ if (req->min_rate > 0)
+ req->rate = req->min_rate;
+
+ return 0;
+}
+
+static int clk_dummy_set_rate(struct clk_hw *hw,
+ unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct clk_dummy_context *ctx =
+ container_of(hw, struct clk_dummy_context, hw);
+
+ ctx->rate = rate;
+ return 0;
+}
+
+static const struct clk_ops clk_dummy_rate_ops = {
+ .recalc_rate = clk_dummy_recalc_rate,
+ .determine_rate = clk_dummy_determine_rate,
+ .set_rate = clk_dummy_set_rate,
+};
+
+static const struct clk_ops clk_dummy_maximize_rate_ops = {
+ .recalc_rate = clk_dummy_recalc_rate,
+ .determine_rate = clk_dummy_maximize_rate,
+ .set_rate = clk_dummy_set_rate,
+};
+
+static const struct clk_ops clk_dummy_minimize_rate_ops = {
+ .recalc_rate = clk_dummy_recalc_rate,
+ .determine_rate = clk_dummy_minimize_rate,
+ .set_rate = clk_dummy_set_rate,
+};
+
+static int clk_test_init_with_ops(struct kunit *test, const struct clk_ops *ops)
+{
+ struct clk_dummy_context *ctx;
+ struct clk_init_data init = { };
+ int ret;
+
+ ctx = kunit_kzalloc(test, sizeof(*ctx), GFP_KERNEL);
+ if (!ctx)
+ return -ENOMEM;
+ ctx->rate = DUMMY_CLOCK_INIT_RATE;
+ test->priv = ctx;
+
+ init.name = "test_dummy_rate";
+ init.ops = ops;
+ ctx->hw.init = &init;
+
+ ret = clk_hw_register(NULL, &ctx->hw);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+static int clk_test_init(struct kunit *test)
+{
+ return clk_test_init_with_ops(test, &clk_dummy_rate_ops);
+}
+
+static int clk_maximize_test_init(struct kunit *test)
+{
+ return clk_test_init_with_ops(test, &clk_dummy_maximize_rate_ops);
+}
+
+static int clk_minimize_test_init(struct kunit *test)
+{
+ return clk_test_init_with_ops(test, &clk_dummy_minimize_rate_ops);
+}
+
+static void clk_test_exit(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+
+ clk_hw_unregister(&ctx->hw);
+}
+
+/*
+ * Test that the actual rate matches what is returned by clk_get_rate()
+ */
+static void clk_test_get_rate(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *clk = hw->clk;
+ unsigned long rate;
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_TRUE(test, rate > 0);
+ KUNIT_EXPECT_EQ(test, rate, ctx->rate);
+}
+
+/*
+ * Test that, after a call to clk_set_rate(), the rate returned by
+ * clk_get_rate() matches.
+ *
+ * This assumes that clk_ops.determine_rate or clk_ops.round_rate won't
+ * modify the requested rate, which is our case in clk_dummy_rate_ops.
+ */
+static void clk_test_set_get_rate(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *clk = hw->clk;
+ unsigned long rate;
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate(clk, DUMMY_CLOCK_RATE_1),
+ 0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_1);
+}
+
+/*
+ * Test that, after several calls to clk_set_rate(), the rate returned
+ * by clk_get_rate() matches the last one.
+ *
+ * This assumes that clk_ops.determine_rate or clk_ops.round_rate won't
+ * modify the requested rate, which is our case in clk_dummy_rate_ops.
+ */
+static void clk_test_set_set_get_rate(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *clk = hw->clk;
+ unsigned long rate;
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate(clk, DUMMY_CLOCK_RATE_1),
+ 0);
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate(clk, DUMMY_CLOCK_RATE_2),
+ 0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_2);
+}
+
+/*
+ * Test that clk_round_rate and clk_set_rate are consitent and will
+ * return the same frequency.
+ */
+static void clk_test_round_set_get_rate(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *clk = hw->clk;
+ unsigned long rounded_rate, set_rate;
+
+ rounded_rate = clk_round_rate(clk, DUMMY_CLOCK_RATE_1);
+ KUNIT_ASSERT_GT(test, rounded_rate, 0);
+ KUNIT_EXPECT_EQ(test, rounded_rate, DUMMY_CLOCK_RATE_1);
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate(clk, DUMMY_CLOCK_RATE_1),
+ 0);
+
+ set_rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, set_rate, 0);
+ KUNIT_EXPECT_EQ(test, rounded_rate, set_rate);
+}
+
+static struct kunit_case clk_test_cases[] = {
+ KUNIT_CASE(clk_test_get_rate),
+ KUNIT_CASE(clk_test_set_get_rate),
+ KUNIT_CASE(clk_test_set_set_get_rate),
+ KUNIT_CASE(clk_test_round_set_get_rate),
+ {}
+};
+
+static struct kunit_suite clk_test_suite = {
+ .name = "clk-test",
+ .init = clk_test_init,
+ .exit = clk_test_exit,
+ .test_cases = clk_test_cases,
+};
+
+/*
+ * Test that clk_set_rate_range won't return an error for a valid range.
+ */
+static void clk_range_test_set_range(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *clk = hw->clk;
+ unsigned long rate;
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(clk,
+ DUMMY_CLOCK_RATE_1,
+ DUMMY_CLOCK_RATE_2),
+ 0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_GE(test, rate, DUMMY_CLOCK_RATE_1);
+ KUNIT_EXPECT_LE(test, rate, DUMMY_CLOCK_RATE_2);
+}
+
+/*
+ * Test that calling clk_set_rate_range with a minimum rate higher than
+ * the maximum rate returns an error.
+ */
+static void clk_range_test_set_range_invalid(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *clk = hw->clk;
+
+ KUNIT_EXPECT_LT(test,
+ clk_set_rate_range(clk,
+ DUMMY_CLOCK_RATE_1 + 1000,
+ DUMMY_CLOCK_RATE_1),
+ 0);
+}
+
+/*
+ * Test that users can't set multiple, disjoints, range that would be
+ * impossible to meet.
+ */
+static void clk_range_test_multiple_disjoints_range(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *user1, *user2;
+
+ user1 = clk_hw_create_clk(NULL, hw, NULL, NULL);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, user1);
+
+ user2 = clk_hw_create_clk(NULL, hw, NULL, NULL);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, user2);
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(user1, 1000, 2000),
+ 0);
+
+ KUNIT_EXPECT_LT(test,
+ clk_set_rate_range(user2, 3000, 4000),
+ 0);
+
+ clk_put(user2);
+ clk_put(user1);
+}
+
+/*
+ * Test that if our clock has some boundaries and we try to round a rate
+ * lower than the minimum, the returned rate won't be affected by the
+ * boundaries.
+ */
+static void clk_range_test_set_range_round_rate_lower(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *clk = hw->clk;
+ long rate;
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(clk,
+ DUMMY_CLOCK_RATE_1,
+ DUMMY_CLOCK_RATE_2),
+ 0);
+
+ rate = clk_round_rate(clk, DUMMY_CLOCK_RATE_1 - 1000);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_1 - 1000);
+}
+
+/*
+ * Test that if our clock has some boundaries and we try to set a rate
+ * lower than the minimum, we'll get an error.
+ */
+static void clk_range_test_set_range_set_rate_lower(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *clk = hw->clk;
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(clk,
+ DUMMY_CLOCK_RATE_1,
+ DUMMY_CLOCK_RATE_2),
+ 0);
+
+ KUNIT_ASSERT_LT(test,
+ clk_set_rate(clk, DUMMY_CLOCK_RATE_1 - 1000),
+ 0);
+}
+
+/*
+ * Test that if our clock has some boundaries and we try to round and
+ * set a rate lower than the minimum, the values won't be consistent
+ * between clk_round_rate() and clk_set_rate().
+ */
+static void clk_range_test_set_range_set_round_rate_consistent_lower(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *clk = hw->clk;
+ long rounded;
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(clk,
+ DUMMY_CLOCK_RATE_1,
+ DUMMY_CLOCK_RATE_2),
+ 0);
+
+ rounded = clk_round_rate(clk, DUMMY_CLOCK_RATE_1 - 1000);
+ KUNIT_ASSERT_GT(test, rounded, 0);
+
+ KUNIT_EXPECT_LT(test,
+ clk_set_rate(clk, DUMMY_CLOCK_RATE_1 - 1000),
+ 0);
+
+ KUNIT_EXPECT_NE(test, rounded, clk_get_rate(clk));
+}
+
+/*
+ * Test that if our clock has some boundaries and we try to round a rate
+ * higher than the maximum, the returned rate won't be affected by the
+ * boundaries.
+ */
+static void clk_range_test_set_range_round_rate_higher(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *clk = hw->clk;
+ long rate;
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(clk,
+ DUMMY_CLOCK_RATE_1,
+ DUMMY_CLOCK_RATE_2),
+ 0);
+
+ rate = clk_round_rate(clk, DUMMY_CLOCK_RATE_2 + 1000);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_2 + 1000);
+}
+
+/*
+ * Test that if our clock has some boundaries and we try to set a rate
+ * lower than the maximum, we'll get an error.
+ */
+static void clk_range_test_set_range_set_rate_higher(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *clk = hw->clk;
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(clk,
+ DUMMY_CLOCK_RATE_1,
+ DUMMY_CLOCK_RATE_2),
+ 0);
+
+ KUNIT_ASSERT_LT(test,
+ clk_set_rate(clk, DUMMY_CLOCK_RATE_2 + 1000),
+ 0);
+}
+
+/*
+ * Test that if our clock has some boundaries and we try to round and
+ * set a rate higher than the maximum, the values won't be consistent
+ * between clk_round_rate() and clk_set_rate().
+ */
+static void clk_range_test_set_range_set_round_rate_consistent_higher(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *clk = hw->clk;
+ long rounded;
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(clk,
+ DUMMY_CLOCK_RATE_1,
+ DUMMY_CLOCK_RATE_2),
+ 0);
+
+ rounded = clk_round_rate(clk, DUMMY_CLOCK_RATE_2 + 1000);
+ KUNIT_ASSERT_GT(test, rounded, 0);
+
+ KUNIT_EXPECT_LT(test,
+ clk_set_rate(clk, DUMMY_CLOCK_RATE_2 + 1000),
+ 0);
+
+ KUNIT_EXPECT_NE(test, rounded, clk_get_rate(clk));
+}
+
+/*
+ * Test that if our clock has a rate lower than the minimum set by a
+ * call to clk_set_rate_range(), the rate will be raised to match the
+ * new minimum.
+ *
+ * This assumes that clk_ops.determine_rate or clk_ops.round_rate won't
+ * modify the requested rate, which is our case in clk_dummy_rate_ops.
+ */
+static void clk_range_test_set_range_get_rate_raised(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *clk = hw->clk;
+ unsigned long rate;
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate(clk, DUMMY_CLOCK_RATE_1 - 1000),
+ 0);
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(clk,
+ DUMMY_CLOCK_RATE_1,
+ DUMMY_CLOCK_RATE_2),
+ 0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_1);
+}
+
+/*
+ * Test that if our clock has a rate higher than the maximum set by a
+ * call to clk_set_rate_range(), the rate will be lowered to match the
+ * new maximum.
+ *
+ * This assumes that clk_ops.determine_rate or clk_ops.round_rate won't
+ * modify the requested rate, which is our case in clk_dummy_rate_ops.
+ */
+static void clk_range_test_set_range_get_rate_lowered(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *clk = hw->clk;
+ unsigned long rate;
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate(clk, DUMMY_CLOCK_RATE_2 + 1000),
+ 0);
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(clk,
+ DUMMY_CLOCK_RATE_1,
+ DUMMY_CLOCK_RATE_2),
+ 0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_2);
+}
+
+static struct kunit_case clk_range_test_cases[] = {
+ KUNIT_CASE(clk_range_test_set_range),
+ KUNIT_CASE(clk_range_test_set_range_invalid),
+ KUNIT_CASE(clk_range_test_multiple_disjoints_range),
+ KUNIT_CASE(clk_range_test_set_range_round_rate_lower),
+ KUNIT_CASE(clk_range_test_set_range_set_rate_lower),
+ KUNIT_CASE(clk_range_test_set_range_set_round_rate_consistent_lower),
+ KUNIT_CASE(clk_range_test_set_range_round_rate_higher),
+ KUNIT_CASE(clk_range_test_set_range_set_rate_higher),
+ KUNIT_CASE(clk_range_test_set_range_set_round_rate_consistent_higher),
+ KUNIT_CASE(clk_range_test_set_range_get_rate_raised),
+ KUNIT_CASE(clk_range_test_set_range_get_rate_lowered),
+ {}
+};
+
+static struct kunit_suite clk_range_test_suite = {
+ .name = "clk-range-test",
+ .init = clk_test_init,
+ .exit = clk_test_exit,
+ .test_cases = clk_range_test_cases,
+};
+
+/*
+ * Test that if:
+ * - we have several subsequent calls to clk_set_rate_range();
+ * - and we have a round_rate ops that always return the maximum
+ * frequency allowed;
+ *
+ * The clock will run at the minimum of all maximum boundaries
+ * requested, even if those boundaries aren't there anymore.
+ */
+static void clk_range_test_set_range_rate_maximized(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *clk = hw->clk;
+ unsigned long rate;
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate(clk, DUMMY_CLOCK_RATE_2 + 1000),
+ 0);
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(clk,
+ DUMMY_CLOCK_RATE_1,
+ DUMMY_CLOCK_RATE_2),
+ 0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_2);
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(clk,
+ DUMMY_CLOCK_RATE_1,
+ DUMMY_CLOCK_RATE_2 - 1000),
+ 0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_2 - 1000);
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(clk,
+ DUMMY_CLOCK_RATE_1,
+ DUMMY_CLOCK_RATE_2),
+ 0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_2 - 1000);
+}
+
+/*
+ * Test that if:
+ * - we have several subsequent calls to clk_set_rate_range(), across
+ * multiple users;
+ * - and we have a round_rate ops that always return the maximum
+ * frequency allowed;
+ *
+ * The clock will run at the minimum of all maximum boundaries
+ * requested, even if those boundaries aren't there anymore.
+ */
+static void clk_range_test_multiple_set_range_rate_maximized(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *clk = hw->clk;
+ struct clk *user1, *user2;
+ unsigned long rate;
+
+ user1 = clk_hw_create_clk(NULL, hw, NULL, NULL);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, user1);
+
+ user2 = clk_hw_create_clk(NULL, hw, NULL, NULL);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, user2);
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate(clk, DUMMY_CLOCK_RATE_2 + 1000),
+ 0);
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(user1,
+ 0,
+ DUMMY_CLOCK_RATE_2),
+ 0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_2);
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(user2,
+ 0,
+ DUMMY_CLOCK_RATE_1),
+ 0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_1);
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(user2, 0, ULONG_MAX),
+ 0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_1);
+
+ clk_put(user2);
+ clk_put(user1);
+}
+
+static struct kunit_case clk_range_maximize_test_cases[] = {
+ KUNIT_CASE(clk_range_test_set_range_rate_maximized),
+ KUNIT_CASE(clk_range_test_multiple_set_range_rate_maximized),
+ {}
+};
+
+static struct kunit_suite clk_range_maximize_test_suite = {
+ .name = "clk-range-maximize-test",
+ .init = clk_maximize_test_init,
+ .exit = clk_test_exit,
+ .test_cases = clk_range_maximize_test_cases,
+};
+
+/*
+ * Test that if:
+ * - we have several subsequent calls to clk_set_rate_range()
+ * - and we have a round_rate ops that always return the minimum
+ * frequency allowed;
+ *
+ * The clock will run at the maximum of all minimum boundaries
+ * requested, even if those boundaries aren't there anymore.
+*/
+static void clk_range_test_set_range_rate_minimized(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *clk = hw->clk;
+ unsigned long rate;
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate(clk, DUMMY_CLOCK_RATE_1 - 1000),
+ 0);
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(clk,
+ DUMMY_CLOCK_RATE_1,
+ DUMMY_CLOCK_RATE_2),
+ 0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_1);
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(clk,
+ DUMMY_CLOCK_RATE_1 + 1000,
+ DUMMY_CLOCK_RATE_2),
+ 0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_1 + 1000);
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(clk,
+ DUMMY_CLOCK_RATE_1,
+ DUMMY_CLOCK_RATE_2),
+ 0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_1 + 1000);
+}
+
+/*
+ * Test that if:
+ * - we have several subsequent calls to clk_set_rate_range(), across
+ * multiple users;
+ * - and we have a round_rate ops that always return the minimum
+ * frequency allowed;
+ *
+ * The clock will run at the maximum of all minimum boundaries
+ * requested, even if those boundaries aren't there anymore.
+*/
+static void clk_range_test_multiple_set_range_rate_minimized(struct kunit *test)
+{
+ struct clk_dummy_context *ctx = test->priv;
+ struct clk_hw *hw = &ctx->hw;
+ struct clk *clk = hw->clk;
+ struct clk *user1, *user2;
+ unsigned long rate;
+
+ user1 = clk_hw_create_clk(NULL, hw, NULL, NULL);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, user1);
+
+ user2 = clk_hw_create_clk(NULL, hw, NULL, NULL);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, user2);
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(user1,
+ DUMMY_CLOCK_RATE_1,
+ ULONG_MAX),
+ 0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_1);
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(user2,
+ DUMMY_CLOCK_RATE_2,
+ ULONG_MAX),
+ 0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_2);
+
+ KUNIT_ASSERT_EQ(test,
+ clk_set_rate_range(user2, 0, ULONG_MAX),
+ 0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_2);
+
+ clk_put(user2);
+ clk_put(user1);
+}
+
+static struct kunit_case clk_range_minimize_test_cases[] = {
+ KUNIT_CASE(clk_range_test_set_range_rate_minimized),
+ KUNIT_CASE(clk_range_test_multiple_set_range_rate_minimized),
+ {}
+};
+
+static struct kunit_suite clk_range_minimize_test_suite = {
+ .name = "clk-range-minimize-test",
+ .init = clk_minimize_test_init,
+ .exit = clk_test_exit,
+ .test_cases = clk_range_minimize_test_cases,
+};
+
+kunit_test_suites(
+ &clk_test_suite,
+ &clk_range_test_suite,
+ &clk_range_maximize_test_suite,
+ &clk_range_minimize_test_suite
+);
+MODULE_LICENSE("GPL v2");
--
2.35.1
^ permalink raw reply related [flat|nested] 26+ messages in thread
* [PATCH v5 02/11] clk: Enforce that disjoints limits are invalid
2022-02-22 13:18 ` Maxime Ripard
@ 2022-02-22 13:18 ` Maxime Ripard
-1 siblings, 0 replies; 26+ messages in thread
From: Maxime Ripard @ 2022-02-22 13:18 UTC (permalink / raw)
To: Mike Turquette, Stephen Boyd
Cc: dri-devel, linux-clk, Dave Stevenson, Phil Elwell, Tim Gover,
Dom Cobley, Maxime Ripard
If we were to have two users of the same clock, doing something like:
clk_set_rate_range(user1, 1000, 2000);
clk_set_rate_range(user2, 3000, 4000);
The second call would fail with -EINVAL, preventing from getting in a
situation where we end up with impossible limits.
However, this is never explicitly checked against and enforced, and
works by relying on an undocumented behaviour of clk_set_rate().
Indeed, on the first clk_set_rate_range will make sure the current clock
rate is within the new range, so it will be between 1000 and 2000Hz. On
the second clk_set_rate_range(), it will consider (rightfully), that our
current clock is outside of the 3000-4000Hz range, and will call
clk_core_set_rate_nolock() to set it to 3000Hz.
clk_core_set_rate_nolock() will then call clk_calc_new_rates() that will
eventually check that our rate 3000Hz rate is outside the min 3000Hz max
2000Hz range, will bail out, the error will propagate and we'll
eventually return -EINVAL.
This solely relies on the fact that clk_calc_new_rates(), and in
particular clk_core_determine_round_nolock(), won't modify the new rate
allowing the error to be reported. That assumption won't be true for all
drivers, and most importantly we'll break that assumption in a later
patch.
It can also be argued that we shouldn't even reach the point where we're
calling clk_core_set_rate_nolock().
Let's make an explicit check for disjoints range before we're doing
anything.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
---
drivers/clk/clk.c | 24 ++++++++++++++++++++++++
1 file changed, 24 insertions(+)
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 8de6a22498e7..276188a6bc2a 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -632,6 +632,24 @@ static void clk_core_get_boundaries(struct clk_core *core,
*max_rate = min(*max_rate, clk_user->max_rate);
}
+static bool clk_core_check_boundaries(struct clk_core *core,
+ unsigned long min_rate,
+ unsigned long max_rate)
+{
+ struct clk *user;
+
+ lockdep_assert_held(&prepare_lock);
+
+ if (min_rate > core->max_rate || max_rate < core->min_rate)
+ return false;
+
+ hlist_for_each_entry(user, &core->clks, clks_node)
+ if (min_rate > user->max_rate || max_rate < user->min_rate)
+ return false;
+
+ return true;
+}
+
void clk_hw_set_rate_range(struct clk_hw *hw, unsigned long min_rate,
unsigned long max_rate)
{
@@ -2348,6 +2366,11 @@ int clk_set_rate_range(struct clk *clk, unsigned long min, unsigned long max)
clk->min_rate = min;
clk->max_rate = max;
+ if (!clk_core_check_boundaries(clk->core, min, max)) {
+ ret = -EINVAL;
+ goto out;
+ }
+
rate = clk_core_get_rate_nolock(clk->core);
if (rate < min || rate > max) {
/*
@@ -2376,6 +2399,7 @@ int clk_set_rate_range(struct clk *clk, unsigned long min, unsigned long max)
}
}
+out:
if (clk->exclusive_count)
clk_core_rate_protect(clk->core);
--
2.35.1
^ permalink raw reply related [flat|nested] 26+ messages in thread
* [PATCH v5 02/11] clk: Enforce that disjoints limits are invalid
@ 2022-02-22 13:18 ` Maxime Ripard
0 siblings, 0 replies; 26+ messages in thread
From: Maxime Ripard @ 2022-02-22 13:18 UTC (permalink / raw)
To: Mike Turquette, Stephen Boyd
Cc: Dom Cobley, Tim Gover, Dave Stevenson, dri-devel, linux-clk,
Maxime Ripard, Phil Elwell
If we were to have two users of the same clock, doing something like:
clk_set_rate_range(user1, 1000, 2000);
clk_set_rate_range(user2, 3000, 4000);
The second call would fail with -EINVAL, preventing from getting in a
situation where we end up with impossible limits.
However, this is never explicitly checked against and enforced, and
works by relying on an undocumented behaviour of clk_set_rate().
Indeed, on the first clk_set_rate_range will make sure the current clock
rate is within the new range, so it will be between 1000 and 2000Hz. On
the second clk_set_rate_range(), it will consider (rightfully), that our
current clock is outside of the 3000-4000Hz range, and will call
clk_core_set_rate_nolock() to set it to 3000Hz.
clk_core_set_rate_nolock() will then call clk_calc_new_rates() that will
eventually check that our rate 3000Hz rate is outside the min 3000Hz max
2000Hz range, will bail out, the error will propagate and we'll
eventually return -EINVAL.
This solely relies on the fact that clk_calc_new_rates(), and in
particular clk_core_determine_round_nolock(), won't modify the new rate
allowing the error to be reported. That assumption won't be true for all
drivers, and most importantly we'll break that assumption in a later
patch.
It can also be argued that we shouldn't even reach the point where we're
calling clk_core_set_rate_nolock().
Let's make an explicit check for disjoints range before we're doing
anything.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
---
drivers/clk/clk.c | 24 ++++++++++++++++++++++++
1 file changed, 24 insertions(+)
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 8de6a22498e7..276188a6bc2a 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -632,6 +632,24 @@ static void clk_core_get_boundaries(struct clk_core *core,
*max_rate = min(*max_rate, clk_user->max_rate);
}
+static bool clk_core_check_boundaries(struct clk_core *core,
+ unsigned long min_rate,
+ unsigned long max_rate)
+{
+ struct clk *user;
+
+ lockdep_assert_held(&prepare_lock);
+
+ if (min_rate > core->max_rate || max_rate < core->min_rate)
+ return false;
+
+ hlist_for_each_entry(user, &core->clks, clks_node)
+ if (min_rate > user->max_rate || max_rate < user->min_rate)
+ return false;
+
+ return true;
+}
+
void clk_hw_set_rate_range(struct clk_hw *hw, unsigned long min_rate,
unsigned long max_rate)
{
@@ -2348,6 +2366,11 @@ int clk_set_rate_range(struct clk *clk, unsigned long min, unsigned long max)
clk->min_rate = min;
clk->max_rate = max;
+ if (!clk_core_check_boundaries(clk->core, min, max)) {
+ ret = -EINVAL;
+ goto out;
+ }
+
rate = clk_core_get_rate_nolock(clk->core);
if (rate < min || rate > max) {
/*
@@ -2376,6 +2399,7 @@ int clk_set_rate_range(struct clk *clk, unsigned long min, unsigned long max)
}
}
+out:
if (clk->exclusive_count)
clk_core_rate_protect(clk->core);
--
2.35.1
^ permalink raw reply related [flat|nested] 26+ messages in thread
* [PATCH v5 03/11] clk: Always clamp the rounded rate
2022-02-22 13:18 ` Maxime Ripard
@ 2022-02-22 13:18 ` Maxime Ripard
-1 siblings, 0 replies; 26+ messages in thread
From: Maxime Ripard @ 2022-02-22 13:18 UTC (permalink / raw)
To: Mike Turquette, Stephen Boyd
Cc: dri-devel, linux-clk, Dave Stevenson, Phil Elwell, Tim Gover,
Dom Cobley, Maxime Ripard
The current core while setting the min and max rate properly in the
clk_request structure will not make sure that the requested rate is
within these boundaries, leaving it to each and every driver to make
sure it is.
It's not clear if this was on purpose or not, but this introduces some
inconsistencies within the API.
For example, a user setting a range and then calling clk_round_rate()
with a value outside of that range will get the same value back
(ignoring any driver adjustements), effectively ignoring the range that
was just set.
Another one, arguably worse, is that it also makes clk_round_rate() and
clk_set_rate() behave differently if there's a range and the rate being
used for both is outside that range. As we have seen, the rate will be
returned unchanged by clk_round_rate(), but clk_set_rate() will error
out returning -EINVAL.
Let's make sure the framework will always clamp the rate to the current
range found on the clock, which will fix both these inconsistencies.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
---
drivers/clk/clk.c | 2 ++
drivers/clk/clk_test.c | 46 +++++++++++++++++++++++++-----------------
2 files changed, 30 insertions(+), 18 deletions(-)
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 276188a6bc2a..9725bdc996b3 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -1348,6 +1348,8 @@ static int clk_core_determine_round_nolock(struct clk_core *core,
if (!core)
return 0;
+ req->rate = clamp(req->rate, req->min_rate, req->max_rate);
+
/*
* At this point, core protection will be disabled
* - if the provider is not protected at all
diff --git a/drivers/clk/clk_test.c b/drivers/clk/clk_test.c
index 8ddfd3b195e1..2b906c594328 100644
--- a/drivers/clk/clk_test.c
+++ b/drivers/clk/clk_test.c
@@ -309,8 +309,7 @@ static void clk_range_test_multiple_disjoints_range(struct kunit *test)
/*
* Test that if our clock has some boundaries and we try to round a rate
- * lower than the minimum, the returned rate won't be affected by the
- * boundaries.
+ * lower than the minimum, the returned rate will be within range.
*/
static void clk_range_test_set_range_round_rate_lower(struct kunit *test)
{
@@ -327,18 +326,19 @@ static void clk_range_test_set_range_round_rate_lower(struct kunit *test)
rate = clk_round_rate(clk, DUMMY_CLOCK_RATE_1 - 1000);
KUNIT_ASSERT_GT(test, rate, 0);
- KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_1 - 1000);
+ KUNIT_EXPECT_TRUE(test, rate >= DUMMY_CLOCK_RATE_1 && rate <= DUMMY_CLOCK_RATE_2);
}
/*
* Test that if our clock has some boundaries and we try to set a rate
- * lower than the minimum, we'll get an error.
+ * higher than the maximum, the new rate will be within range.
*/
static void clk_range_test_set_range_set_rate_lower(struct kunit *test)
{
struct clk_dummy_context *ctx = test->priv;
struct clk_hw *hw = &ctx->hw;
struct clk *clk = hw->clk;
+ unsigned long rate;
KUNIT_ASSERT_EQ(test,
clk_set_rate_range(clk,
@@ -346,15 +346,20 @@ static void clk_range_test_set_range_set_rate_lower(struct kunit *test)
DUMMY_CLOCK_RATE_2),
0);
- KUNIT_ASSERT_LT(test,
+ KUNIT_ASSERT_EQ(test,
clk_set_rate(clk, DUMMY_CLOCK_RATE_1 - 1000),
0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_TRUE(test, rate >= DUMMY_CLOCK_RATE_1 && rate <= DUMMY_CLOCK_RATE_2);
}
/*
* Test that if our clock has some boundaries and we try to round and
- * set a rate lower than the minimum, the values won't be consistent
- * between clk_round_rate() and clk_set_rate().
+ * set a rate lower than the minimum, the rate returned by
+ * clk_round_rate() will be consistent with the new rate set by
+ * clk_set_rate().
*/
static void clk_range_test_set_range_set_round_rate_consistent_lower(struct kunit *test)
{
@@ -372,17 +377,16 @@ static void clk_range_test_set_range_set_round_rate_consistent_lower(struct kuni
rounded = clk_round_rate(clk, DUMMY_CLOCK_RATE_1 - 1000);
KUNIT_ASSERT_GT(test, rounded, 0);
- KUNIT_EXPECT_LT(test,
+ KUNIT_ASSERT_EQ(test,
clk_set_rate(clk, DUMMY_CLOCK_RATE_1 - 1000),
0);
- KUNIT_EXPECT_NE(test, rounded, clk_get_rate(clk));
+ KUNIT_EXPECT_EQ(test, rounded, clk_get_rate(clk));
}
/*
* Test that if our clock has some boundaries and we try to round a rate
- * higher than the maximum, the returned rate won't be affected by the
- * boundaries.
+ * higher than the maximum, the returned rate will be within range.
*/
static void clk_range_test_set_range_round_rate_higher(struct kunit *test)
{
@@ -399,18 +403,19 @@ static void clk_range_test_set_range_round_rate_higher(struct kunit *test)
rate = clk_round_rate(clk, DUMMY_CLOCK_RATE_2 + 1000);
KUNIT_ASSERT_GT(test, rate, 0);
- KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_2 + 1000);
+ KUNIT_EXPECT_TRUE(test, rate >= DUMMY_CLOCK_RATE_1 && rate <= DUMMY_CLOCK_RATE_2);
}
/*
* Test that if our clock has some boundaries and we try to set a rate
- * lower than the maximum, we'll get an error.
+ * higher than the maximum, the new rate will be within range.
*/
static void clk_range_test_set_range_set_rate_higher(struct kunit *test)
{
struct clk_dummy_context *ctx = test->priv;
struct clk_hw *hw = &ctx->hw;
struct clk *clk = hw->clk;
+ unsigned long rate;
KUNIT_ASSERT_EQ(test,
clk_set_rate_range(clk,
@@ -418,15 +423,20 @@ static void clk_range_test_set_range_set_rate_higher(struct kunit *test)
DUMMY_CLOCK_RATE_2),
0);
- KUNIT_ASSERT_LT(test,
+ KUNIT_ASSERT_EQ(test,
clk_set_rate(clk, DUMMY_CLOCK_RATE_2 + 1000),
0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_TRUE(test, rate >= DUMMY_CLOCK_RATE_1 && rate <= DUMMY_CLOCK_RATE_2);
}
/*
* Test that if our clock has some boundaries and we try to round and
- * set a rate higher than the maximum, the values won't be consistent
- * between clk_round_rate() and clk_set_rate().
+ * set a rate higher than the maximum, the rate returned by
+ * clk_round_rate() will be consistent with the new rate set by
+ * clk_set_rate().
*/
static void clk_range_test_set_range_set_round_rate_consistent_higher(struct kunit *test)
{
@@ -444,11 +454,11 @@ static void clk_range_test_set_range_set_round_rate_consistent_higher(struct kun
rounded = clk_round_rate(clk, DUMMY_CLOCK_RATE_2 + 1000);
KUNIT_ASSERT_GT(test, rounded, 0);
- KUNIT_EXPECT_LT(test,
+ KUNIT_ASSERT_EQ(test,
clk_set_rate(clk, DUMMY_CLOCK_RATE_2 + 1000),
0);
- KUNIT_EXPECT_NE(test, rounded, clk_get_rate(clk));
+ KUNIT_EXPECT_EQ(test, rounded, clk_get_rate(clk));
}
/*
--
2.35.1
^ permalink raw reply related [flat|nested] 26+ messages in thread
* [PATCH v5 03/11] clk: Always clamp the rounded rate
@ 2022-02-22 13:18 ` Maxime Ripard
0 siblings, 0 replies; 26+ messages in thread
From: Maxime Ripard @ 2022-02-22 13:18 UTC (permalink / raw)
To: Mike Turquette, Stephen Boyd
Cc: Dom Cobley, Tim Gover, Dave Stevenson, dri-devel, linux-clk,
Maxime Ripard, Phil Elwell
The current core while setting the min and max rate properly in the
clk_request structure will not make sure that the requested rate is
within these boundaries, leaving it to each and every driver to make
sure it is.
It's not clear if this was on purpose or not, but this introduces some
inconsistencies within the API.
For example, a user setting a range and then calling clk_round_rate()
with a value outside of that range will get the same value back
(ignoring any driver adjustements), effectively ignoring the range that
was just set.
Another one, arguably worse, is that it also makes clk_round_rate() and
clk_set_rate() behave differently if there's a range and the rate being
used for both is outside that range. As we have seen, the rate will be
returned unchanged by clk_round_rate(), but clk_set_rate() will error
out returning -EINVAL.
Let's make sure the framework will always clamp the rate to the current
range found on the clock, which will fix both these inconsistencies.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
---
drivers/clk/clk.c | 2 ++
drivers/clk/clk_test.c | 46 +++++++++++++++++++++++++-----------------
2 files changed, 30 insertions(+), 18 deletions(-)
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 276188a6bc2a..9725bdc996b3 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -1348,6 +1348,8 @@ static int clk_core_determine_round_nolock(struct clk_core *core,
if (!core)
return 0;
+ req->rate = clamp(req->rate, req->min_rate, req->max_rate);
+
/*
* At this point, core protection will be disabled
* - if the provider is not protected at all
diff --git a/drivers/clk/clk_test.c b/drivers/clk/clk_test.c
index 8ddfd3b195e1..2b906c594328 100644
--- a/drivers/clk/clk_test.c
+++ b/drivers/clk/clk_test.c
@@ -309,8 +309,7 @@ static void clk_range_test_multiple_disjoints_range(struct kunit *test)
/*
* Test that if our clock has some boundaries and we try to round a rate
- * lower than the minimum, the returned rate won't be affected by the
- * boundaries.
+ * lower than the minimum, the returned rate will be within range.
*/
static void clk_range_test_set_range_round_rate_lower(struct kunit *test)
{
@@ -327,18 +326,19 @@ static void clk_range_test_set_range_round_rate_lower(struct kunit *test)
rate = clk_round_rate(clk, DUMMY_CLOCK_RATE_1 - 1000);
KUNIT_ASSERT_GT(test, rate, 0);
- KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_1 - 1000);
+ KUNIT_EXPECT_TRUE(test, rate >= DUMMY_CLOCK_RATE_1 && rate <= DUMMY_CLOCK_RATE_2);
}
/*
* Test that if our clock has some boundaries and we try to set a rate
- * lower than the minimum, we'll get an error.
+ * higher than the maximum, the new rate will be within range.
*/
static void clk_range_test_set_range_set_rate_lower(struct kunit *test)
{
struct clk_dummy_context *ctx = test->priv;
struct clk_hw *hw = &ctx->hw;
struct clk *clk = hw->clk;
+ unsigned long rate;
KUNIT_ASSERT_EQ(test,
clk_set_rate_range(clk,
@@ -346,15 +346,20 @@ static void clk_range_test_set_range_set_rate_lower(struct kunit *test)
DUMMY_CLOCK_RATE_2),
0);
- KUNIT_ASSERT_LT(test,
+ KUNIT_ASSERT_EQ(test,
clk_set_rate(clk, DUMMY_CLOCK_RATE_1 - 1000),
0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_TRUE(test, rate >= DUMMY_CLOCK_RATE_1 && rate <= DUMMY_CLOCK_RATE_2);
}
/*
* Test that if our clock has some boundaries and we try to round and
- * set a rate lower than the minimum, the values won't be consistent
- * between clk_round_rate() and clk_set_rate().
+ * set a rate lower than the minimum, the rate returned by
+ * clk_round_rate() will be consistent with the new rate set by
+ * clk_set_rate().
*/
static void clk_range_test_set_range_set_round_rate_consistent_lower(struct kunit *test)
{
@@ -372,17 +377,16 @@ static void clk_range_test_set_range_set_round_rate_consistent_lower(struct kuni
rounded = clk_round_rate(clk, DUMMY_CLOCK_RATE_1 - 1000);
KUNIT_ASSERT_GT(test, rounded, 0);
- KUNIT_EXPECT_LT(test,
+ KUNIT_ASSERT_EQ(test,
clk_set_rate(clk, DUMMY_CLOCK_RATE_1 - 1000),
0);
- KUNIT_EXPECT_NE(test, rounded, clk_get_rate(clk));
+ KUNIT_EXPECT_EQ(test, rounded, clk_get_rate(clk));
}
/*
* Test that if our clock has some boundaries and we try to round a rate
- * higher than the maximum, the returned rate won't be affected by the
- * boundaries.
+ * higher than the maximum, the returned rate will be within range.
*/
static void clk_range_test_set_range_round_rate_higher(struct kunit *test)
{
@@ -399,18 +403,19 @@ static void clk_range_test_set_range_round_rate_higher(struct kunit *test)
rate = clk_round_rate(clk, DUMMY_CLOCK_RATE_2 + 1000);
KUNIT_ASSERT_GT(test, rate, 0);
- KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_2 + 1000);
+ KUNIT_EXPECT_TRUE(test, rate >= DUMMY_CLOCK_RATE_1 && rate <= DUMMY_CLOCK_RATE_2);
}
/*
* Test that if our clock has some boundaries and we try to set a rate
- * lower than the maximum, we'll get an error.
+ * higher than the maximum, the new rate will be within range.
*/
static void clk_range_test_set_range_set_rate_higher(struct kunit *test)
{
struct clk_dummy_context *ctx = test->priv;
struct clk_hw *hw = &ctx->hw;
struct clk *clk = hw->clk;
+ unsigned long rate;
KUNIT_ASSERT_EQ(test,
clk_set_rate_range(clk,
@@ -418,15 +423,20 @@ static void clk_range_test_set_range_set_rate_higher(struct kunit *test)
DUMMY_CLOCK_RATE_2),
0);
- KUNIT_ASSERT_LT(test,
+ KUNIT_ASSERT_EQ(test,
clk_set_rate(clk, DUMMY_CLOCK_RATE_2 + 1000),
0);
+
+ rate = clk_get_rate(clk);
+ KUNIT_ASSERT_GT(test, rate, 0);
+ KUNIT_EXPECT_TRUE(test, rate >= DUMMY_CLOCK_RATE_1 && rate <= DUMMY_CLOCK_RATE_2);
}
/*
* Test that if our clock has some boundaries and we try to round and
- * set a rate higher than the maximum, the values won't be consistent
- * between clk_round_rate() and clk_set_rate().
+ * set a rate higher than the maximum, the rate returned by
+ * clk_round_rate() will be consistent with the new rate set by
+ * clk_set_rate().
*/
static void clk_range_test_set_range_set_round_rate_consistent_higher(struct kunit *test)
{
@@ -444,11 +454,11 @@ static void clk_range_test_set_range_set_round_rate_consistent_higher(struct kun
rounded = clk_round_rate(clk, DUMMY_CLOCK_RATE_2 + 1000);
KUNIT_ASSERT_GT(test, rounded, 0);
- KUNIT_EXPECT_LT(test,
+ KUNIT_ASSERT_EQ(test,
clk_set_rate(clk, DUMMY_CLOCK_RATE_2 + 1000),
0);
- KUNIT_EXPECT_NE(test, rounded, clk_get_rate(clk));
+ KUNIT_EXPECT_EQ(test, rounded, clk_get_rate(clk));
}
/*
--
2.35.1
^ permalink raw reply related [flat|nested] 26+ messages in thread
* [PATCH v5 04/11] clk: Use clamp instead of open-coding our own
2022-02-22 13:18 ` Maxime Ripard
@ 2022-02-22 13:18 ` Maxime Ripard
-1 siblings, 0 replies; 26+ messages in thread
From: Maxime Ripard @ 2022-02-22 13:18 UTC (permalink / raw)
To: Mike Turquette, Stephen Boyd
Cc: dri-devel, linux-clk, Dave Stevenson, Phil Elwell, Tim Gover,
Dom Cobley, Maxime Ripard
The code in clk_set_rate_range() will, if the current rate is outside of
the new range, will force it to the minimum or maximum.
Since it's running under the condition that the rate is either lower
than the minimum, or higher than the maximum, this is equivalent to
using clamp, while being less readable. Let's switch to using clamp
instead.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
---
drivers/clk/clk.c | 6 +-----
1 file changed, 1 insertion(+), 5 deletions(-)
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 9725bdc996b3..fd3daa11bfa4 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -2388,11 +2388,7 @@ int clk_set_rate_range(struct clk *clk, unsigned long min, unsigned long max)
* this corner case when determining the rate
*/
- if (rate < min)
- rate = min;
- else
- rate = max;
-
+ rate = clamp(clk->core->req_rate, min, max);
ret = clk_core_set_rate_nolock(clk->core, rate);
if (ret) {
/* rollback the changes */
--
2.35.1
^ permalink raw reply related [flat|nested] 26+ messages in thread
* [PATCH v5 04/11] clk: Use clamp instead of open-coding our own
@ 2022-02-22 13:18 ` Maxime Ripard
0 siblings, 0 replies; 26+ messages in thread
From: Maxime Ripard @ 2022-02-22 13:18 UTC (permalink / raw)
To: Mike Turquette, Stephen Boyd
Cc: Dom Cobley, Tim Gover, Dave Stevenson, dri-devel, linux-clk,
Maxime Ripard, Phil Elwell
The code in clk_set_rate_range() will, if the current rate is outside of
the new range, will force it to the minimum or maximum.
Since it's running under the condition that the rate is either lower
than the minimum, or higher than the maximum, this is equivalent to
using clamp, while being less readable. Let's switch to using clamp
instead.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
---
drivers/clk/clk.c | 6 +-----
1 file changed, 1 insertion(+), 5 deletions(-)
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 9725bdc996b3..fd3daa11bfa4 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -2388,11 +2388,7 @@ int clk_set_rate_range(struct clk *clk, unsigned long min, unsigned long max)
* this corner case when determining the rate
*/
- if (rate < min)
- rate = min;
- else
- rate = max;
-
+ rate = clamp(clk->core->req_rate, min, max);
ret = clk_core_set_rate_nolock(clk->core, rate);
if (ret) {
/* rollback the changes */
--
2.35.1
^ permalink raw reply related [flat|nested] 26+ messages in thread
* [PATCH v5 05/11] clk: Always set the rate on clk_set_range_rate
2022-02-22 13:18 ` Maxime Ripard
@ 2022-02-22 13:18 ` Maxime Ripard
-1 siblings, 0 replies; 26+ messages in thread
From: Maxime Ripard @ 2022-02-22 13:18 UTC (permalink / raw)
To: Mike Turquette, Stephen Boyd
Cc: dri-devel, linux-clk, Dave Stevenson, Phil Elwell, Tim Gover,
Dom Cobley, Maxime Ripard
When we change a clock minimum or maximum using clk_set_rate_range(),
clk_set_min_rate() or clk_set_max_rate(), the current code will only
trigger a new rate change if the rate is outside of the new boundaries.
However, a clock driver might want to always keep the clock rate to
one of its boundary, for example the minimum to keep the power
consumption as low as possible.
Since they don't always get called though, clock providers don't have the
opportunity to implement this behaviour.
Let's trigger a clk_set_rate() on the previous requested rate every time
clk_set_rate_range() is called. That way, providers that care about the
new boundaries have a chance to adjust the rate, while providers that
don't care about those new boundaries will return the same rate than
before, which will be ignored by clk_set_rate() and won't result in a
new rate change.
Suggested-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
---
drivers/clk/clk.c | 45 ++++++++++++++++----------------
drivers/clk/clk_test.c | 58 +++++++++++++++++++-----------------------
2 files changed, 49 insertions(+), 54 deletions(-)
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index fd3daa11bfa4..9ee9ef0601c5 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -2373,28 +2373,29 @@ int clk_set_rate_range(struct clk *clk, unsigned long min, unsigned long max)
goto out;
}
- rate = clk_core_get_rate_nolock(clk->core);
- if (rate < min || rate > max) {
- /*
- * FIXME:
- * We are in bit of trouble here, current rate is outside the
- * the requested range. We are going try to request appropriate
- * range boundary but there is a catch. It may fail for the
- * usual reason (clock broken, clock protected, etc) but also
- * because:
- * - round_rate() was not favorable and fell on the wrong
- * side of the boundary
- * - the determine_rate() callback does not really check for
- * this corner case when determining the rate
- */
-
- rate = clamp(clk->core->req_rate, min, max);
- ret = clk_core_set_rate_nolock(clk->core, rate);
- if (ret) {
- /* rollback the changes */
- clk->min_rate = old_min;
- clk->max_rate = old_max;
- }
+ /*
+ * Since the boundaries have been changed, let's give the
+ * opportunity to the provider to adjust the clock rate based on
+ * the new boundaries.
+ *
+ * We also need to handle the case where the clock is currently
+ * outside of the boundaries. Clamping the last requested rate
+ * to the current minimum and maximum will also handle this.
+ *
+ * FIXME:
+ * There is a catch. It may fail for the usual reason (clock
+ * broken, clock protected, etc) but also because:
+ * - round_rate() was not favorable and fell on the wrong
+ * side of the boundary
+ * - the determine_rate() callback does not really check for
+ * this corner case when determining the rate
+ */
+ rate = clamp(clk->core->req_rate, min, max);
+ ret = clk_core_set_rate_nolock(clk->core, rate);
+ if (ret) {
+ /* rollback the changes */
+ clk->min_rate = old_min;
+ clk->max_rate = old_max;
}
out:
diff --git a/drivers/clk/clk_test.c b/drivers/clk/clk_test.c
index 2b906c594328..b23859d1b460 100644
--- a/drivers/clk/clk_test.c
+++ b/drivers/clk/clk_test.c
@@ -544,13 +544,12 @@ static struct kunit_suite clk_range_test_suite = {
};
/*
- * Test that if:
- * - we have several subsequent calls to clk_set_rate_range();
- * - and we have a round_rate ops that always return the maximum
- * frequency allowed;
+ * Test that if we have several subsequent calls to
+ * clk_set_rate_range(), the core will reevaluate whether a new rate is
+ * needed each and every time.
*
- * The clock will run at the minimum of all maximum boundaries
- * requested, even if those boundaries aren't there anymore.
+ * With clk_dummy_maximize_rate_ops, this means that the the rate will
+ * trail along the maximum as it evolves.
*/
static void clk_range_test_set_range_rate_maximized(struct kunit *test)
{
@@ -591,18 +590,16 @@ static void clk_range_test_set_range_rate_maximized(struct kunit *test)
rate = clk_get_rate(clk);
KUNIT_ASSERT_GT(test, rate, 0);
- KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_2 - 1000);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_2);
}
/*
- * Test that if:
- * - we have several subsequent calls to clk_set_rate_range(), across
- * multiple users;
- * - and we have a round_rate ops that always return the maximum
- * frequency allowed;
+ * Test that if we have several subsequent calls to
+ * clk_set_rate_range(), across multiple users, the core will reevaluate
+ * whether a new rate is needed each and every time.
*
- * The clock will run at the minimum of all maximum boundaries
- * requested, even if those boundaries aren't there anymore.
+ * With clk_dummy_maximize_rate_ops, this means that the the rate will
+ * trail along the maximum as it evolves.
*/
static void clk_range_test_multiple_set_range_rate_maximized(struct kunit *test)
{
@@ -648,7 +645,7 @@ static void clk_range_test_multiple_set_range_rate_maximized(struct kunit *test)
rate = clk_get_rate(clk);
KUNIT_ASSERT_GT(test, rate, 0);
- KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_1);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_2);
clk_put(user2);
clk_put(user1);
@@ -668,14 +665,13 @@ static struct kunit_suite clk_range_maximize_test_suite = {
};
/*
- * Test that if:
- * - we have several subsequent calls to clk_set_rate_range()
- * - and we have a round_rate ops that always return the minimum
- * frequency allowed;
+ * Test that if we have several subsequent calls to
+ * clk_set_rate_range(), the core will reevaluate whether a new rate is
+ * needed each and every time.
*
- * The clock will run at the maximum of all minimum boundaries
- * requested, even if those boundaries aren't there anymore.
-*/
+ * With clk_dummy_minimize_rate_ops, this means that the the rate will
+ * trail along the minimum as it evolves.
+ */
static void clk_range_test_set_range_rate_minimized(struct kunit *test)
{
struct clk_dummy_context *ctx = test->priv;
@@ -715,19 +711,17 @@ static void clk_range_test_set_range_rate_minimized(struct kunit *test)
rate = clk_get_rate(clk);
KUNIT_ASSERT_GT(test, rate, 0);
- KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_1 + 1000);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_1);
}
/*
- * Test that if:
- * - we have several subsequent calls to clk_set_rate_range(), across
- * multiple users;
- * - and we have a round_rate ops that always return the minimum
- * frequency allowed;
+ * Test that if we have several subsequent calls to
+ * clk_set_rate_range(), across multiple users, the core will reevaluate
+ * whether a new rate is needed each and every time.
*
- * The clock will run at the maximum of all minimum boundaries
- * requested, even if those boundaries aren't there anymore.
-*/
+ * With clk_dummy_minimize_rate_ops, this means that the the rate will
+ * trail along the minimum as it evolves.
+ */
static void clk_range_test_multiple_set_range_rate_minimized(struct kunit *test)
{
struct clk_dummy_context *ctx = test->priv;
@@ -768,7 +762,7 @@ static void clk_range_test_multiple_set_range_rate_minimized(struct kunit *test)
rate = clk_get_rate(clk);
KUNIT_ASSERT_GT(test, rate, 0);
- KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_2);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_1);
clk_put(user2);
clk_put(user1);
--
2.35.1
^ permalink raw reply related [flat|nested] 26+ messages in thread
* [PATCH v5 05/11] clk: Always set the rate on clk_set_range_rate
@ 2022-02-22 13:18 ` Maxime Ripard
0 siblings, 0 replies; 26+ messages in thread
From: Maxime Ripard @ 2022-02-22 13:18 UTC (permalink / raw)
To: Mike Turquette, Stephen Boyd
Cc: Dom Cobley, Tim Gover, Dave Stevenson, dri-devel, linux-clk,
Maxime Ripard, Phil Elwell
When we change a clock minimum or maximum using clk_set_rate_range(),
clk_set_min_rate() or clk_set_max_rate(), the current code will only
trigger a new rate change if the rate is outside of the new boundaries.
However, a clock driver might want to always keep the clock rate to
one of its boundary, for example the minimum to keep the power
consumption as low as possible.
Since they don't always get called though, clock providers don't have the
opportunity to implement this behaviour.
Let's trigger a clk_set_rate() on the previous requested rate every time
clk_set_rate_range() is called. That way, providers that care about the
new boundaries have a chance to adjust the rate, while providers that
don't care about those new boundaries will return the same rate than
before, which will be ignored by clk_set_rate() and won't result in a
new rate change.
Suggested-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
---
drivers/clk/clk.c | 45 ++++++++++++++++----------------
drivers/clk/clk_test.c | 58 +++++++++++++++++++-----------------------
2 files changed, 49 insertions(+), 54 deletions(-)
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index fd3daa11bfa4..9ee9ef0601c5 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -2373,28 +2373,29 @@ int clk_set_rate_range(struct clk *clk, unsigned long min, unsigned long max)
goto out;
}
- rate = clk_core_get_rate_nolock(clk->core);
- if (rate < min || rate > max) {
- /*
- * FIXME:
- * We are in bit of trouble here, current rate is outside the
- * the requested range. We are going try to request appropriate
- * range boundary but there is a catch. It may fail for the
- * usual reason (clock broken, clock protected, etc) but also
- * because:
- * - round_rate() was not favorable and fell on the wrong
- * side of the boundary
- * - the determine_rate() callback does not really check for
- * this corner case when determining the rate
- */
-
- rate = clamp(clk->core->req_rate, min, max);
- ret = clk_core_set_rate_nolock(clk->core, rate);
- if (ret) {
- /* rollback the changes */
- clk->min_rate = old_min;
- clk->max_rate = old_max;
- }
+ /*
+ * Since the boundaries have been changed, let's give the
+ * opportunity to the provider to adjust the clock rate based on
+ * the new boundaries.
+ *
+ * We also need to handle the case where the clock is currently
+ * outside of the boundaries. Clamping the last requested rate
+ * to the current minimum and maximum will also handle this.
+ *
+ * FIXME:
+ * There is a catch. It may fail for the usual reason (clock
+ * broken, clock protected, etc) but also because:
+ * - round_rate() was not favorable and fell on the wrong
+ * side of the boundary
+ * - the determine_rate() callback does not really check for
+ * this corner case when determining the rate
+ */
+ rate = clamp(clk->core->req_rate, min, max);
+ ret = clk_core_set_rate_nolock(clk->core, rate);
+ if (ret) {
+ /* rollback the changes */
+ clk->min_rate = old_min;
+ clk->max_rate = old_max;
}
out:
diff --git a/drivers/clk/clk_test.c b/drivers/clk/clk_test.c
index 2b906c594328..b23859d1b460 100644
--- a/drivers/clk/clk_test.c
+++ b/drivers/clk/clk_test.c
@@ -544,13 +544,12 @@ static struct kunit_suite clk_range_test_suite = {
};
/*
- * Test that if:
- * - we have several subsequent calls to clk_set_rate_range();
- * - and we have a round_rate ops that always return the maximum
- * frequency allowed;
+ * Test that if we have several subsequent calls to
+ * clk_set_rate_range(), the core will reevaluate whether a new rate is
+ * needed each and every time.
*
- * The clock will run at the minimum of all maximum boundaries
- * requested, even if those boundaries aren't there anymore.
+ * With clk_dummy_maximize_rate_ops, this means that the the rate will
+ * trail along the maximum as it evolves.
*/
static void clk_range_test_set_range_rate_maximized(struct kunit *test)
{
@@ -591,18 +590,16 @@ static void clk_range_test_set_range_rate_maximized(struct kunit *test)
rate = clk_get_rate(clk);
KUNIT_ASSERT_GT(test, rate, 0);
- KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_2 - 1000);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_2);
}
/*
- * Test that if:
- * - we have several subsequent calls to clk_set_rate_range(), across
- * multiple users;
- * - and we have a round_rate ops that always return the maximum
- * frequency allowed;
+ * Test that if we have several subsequent calls to
+ * clk_set_rate_range(), across multiple users, the core will reevaluate
+ * whether a new rate is needed each and every time.
*
- * The clock will run at the minimum of all maximum boundaries
- * requested, even if those boundaries aren't there anymore.
+ * With clk_dummy_maximize_rate_ops, this means that the the rate will
+ * trail along the maximum as it evolves.
*/
static void clk_range_test_multiple_set_range_rate_maximized(struct kunit *test)
{
@@ -648,7 +645,7 @@ static void clk_range_test_multiple_set_range_rate_maximized(struct kunit *test)
rate = clk_get_rate(clk);
KUNIT_ASSERT_GT(test, rate, 0);
- KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_1);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_2);
clk_put(user2);
clk_put(user1);
@@ -668,14 +665,13 @@ static struct kunit_suite clk_range_maximize_test_suite = {
};
/*
- * Test that if:
- * - we have several subsequent calls to clk_set_rate_range()
- * - and we have a round_rate ops that always return the minimum
- * frequency allowed;
+ * Test that if we have several subsequent calls to
+ * clk_set_rate_range(), the core will reevaluate whether a new rate is
+ * needed each and every time.
*
- * The clock will run at the maximum of all minimum boundaries
- * requested, even if those boundaries aren't there anymore.
-*/
+ * With clk_dummy_minimize_rate_ops, this means that the the rate will
+ * trail along the minimum as it evolves.
+ */
static void clk_range_test_set_range_rate_minimized(struct kunit *test)
{
struct clk_dummy_context *ctx = test->priv;
@@ -715,19 +711,17 @@ static void clk_range_test_set_range_rate_minimized(struct kunit *test)
rate = clk_get_rate(clk);
KUNIT_ASSERT_GT(test, rate, 0);
- KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_1 + 1000);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_1);
}
/*
- * Test that if:
- * - we have several subsequent calls to clk_set_rate_range(), across
- * multiple users;
- * - and we have a round_rate ops that always return the minimum
- * frequency allowed;
+ * Test that if we have several subsequent calls to
+ * clk_set_rate_range(), across multiple users, the core will reevaluate
+ * whether a new rate is needed each and every time.
*
- * The clock will run at the maximum of all minimum boundaries
- * requested, even if those boundaries aren't there anymore.
-*/
+ * With clk_dummy_minimize_rate_ops, this means that the the rate will
+ * trail along the minimum as it evolves.
+ */
static void clk_range_test_multiple_set_range_rate_minimized(struct kunit *test)
{
struct clk_dummy_context *ctx = test->priv;
@@ -768,7 +762,7 @@ static void clk_range_test_multiple_set_range_rate_minimized(struct kunit *test)
rate = clk_get_rate(clk);
KUNIT_ASSERT_GT(test, rate, 0);
- KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_2);
+ KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_1);
clk_put(user2);
clk_put(user1);
--
2.35.1
^ permalink raw reply related [flat|nested] 26+ messages in thread
* [PATCH v5 06/11] clk: Add clk_drop_range
2022-02-22 13:18 ` Maxime Ripard
@ 2022-02-22 13:18 ` Maxime Ripard
-1 siblings, 0 replies; 26+ messages in thread
From: Maxime Ripard @ 2022-02-22 13:18 UTC (permalink / raw)
To: Mike Turquette, Stephen Boyd
Cc: dri-devel, linux-clk, Dave Stevenson, Phil Elwell, Tim Gover,
Dom Cobley, Maxime Ripard
In order to reset the range on a clock, we need to call
clk_set_rate_range with a minimum of 0 and a maximum of ULONG_MAX. Since
it's fairly inconvenient, let's introduce a clk_drop_range() function
that will do just this.
Suggested-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
---
drivers/clk/clk_test.c | 4 ++--
include/linux/clk.h | 11 +++++++++++
2 files changed, 13 insertions(+), 2 deletions(-)
diff --git a/drivers/clk/clk_test.c b/drivers/clk/clk_test.c
index b23859d1b460..f108e2dcc351 100644
--- a/drivers/clk/clk_test.c
+++ b/drivers/clk/clk_test.c
@@ -640,7 +640,7 @@ static void clk_range_test_multiple_set_range_rate_maximized(struct kunit *test)
KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_1);
KUNIT_ASSERT_EQ(test,
- clk_set_rate_range(user2, 0, ULONG_MAX),
+ clk_drop_range(user2),
0);
rate = clk_get_rate(clk);
@@ -757,7 +757,7 @@ static void clk_range_test_multiple_set_range_rate_minimized(struct kunit *test)
KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_2);
KUNIT_ASSERT_EQ(test,
- clk_set_rate_range(user2, 0, ULONG_MAX),
+ clk_drop_range(user2),
0);
rate = clk_get_rate(clk);
diff --git a/include/linux/clk.h b/include/linux/clk.h
index 266e8de3cb51..39faa54efe88 100644
--- a/include/linux/clk.h
+++ b/include/linux/clk.h
@@ -986,6 +986,17 @@ static inline void clk_bulk_disable_unprepare(int num_clks,
clk_bulk_unprepare(num_clks, clks);
}
+/**
+ * clk_drop_range - Reset any range set on that clock
+ * @clk: clock source
+ *
+ * Returns success (0) or negative errno.
+ */
+static inline int clk_drop_range(struct clk *clk)
+{
+ return clk_set_rate_range(clk, 0, ULONG_MAX);
+}
+
/**
* clk_get_optional - lookup and obtain a reference to an optional clock
* producer.
--
2.35.1
^ permalink raw reply related [flat|nested] 26+ messages in thread
* [PATCH v5 06/11] clk: Add clk_drop_range
@ 2022-02-22 13:18 ` Maxime Ripard
0 siblings, 0 replies; 26+ messages in thread
From: Maxime Ripard @ 2022-02-22 13:18 UTC (permalink / raw)
To: Mike Turquette, Stephen Boyd
Cc: Dom Cobley, Tim Gover, Dave Stevenson, dri-devel, linux-clk,
Maxime Ripard, Phil Elwell
In order to reset the range on a clock, we need to call
clk_set_rate_range with a minimum of 0 and a maximum of ULONG_MAX. Since
it's fairly inconvenient, let's introduce a clk_drop_range() function
that will do just this.
Suggested-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
---
drivers/clk/clk_test.c | 4 ++--
include/linux/clk.h | 11 +++++++++++
2 files changed, 13 insertions(+), 2 deletions(-)
diff --git a/drivers/clk/clk_test.c b/drivers/clk/clk_test.c
index b23859d1b460..f108e2dcc351 100644
--- a/drivers/clk/clk_test.c
+++ b/drivers/clk/clk_test.c
@@ -640,7 +640,7 @@ static void clk_range_test_multiple_set_range_rate_maximized(struct kunit *test)
KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_1);
KUNIT_ASSERT_EQ(test,
- clk_set_rate_range(user2, 0, ULONG_MAX),
+ clk_drop_range(user2),
0);
rate = clk_get_rate(clk);
@@ -757,7 +757,7 @@ static void clk_range_test_multiple_set_range_rate_minimized(struct kunit *test)
KUNIT_EXPECT_EQ(test, rate, DUMMY_CLOCK_RATE_2);
KUNIT_ASSERT_EQ(test,
- clk_set_rate_range(user2, 0, ULONG_MAX),
+ clk_drop_range(user2),
0);
rate = clk_get_rate(clk);
diff --git a/include/linux/clk.h b/include/linux/clk.h
index 266e8de3cb51..39faa54efe88 100644
--- a/include/linux/clk.h
+++ b/include/linux/clk.h
@@ -986,6 +986,17 @@ static inline void clk_bulk_disable_unprepare(int num_clks,
clk_bulk_unprepare(num_clks, clks);
}
+/**
+ * clk_drop_range - Reset any range set on that clock
+ * @clk: clock source
+ *
+ * Returns success (0) or negative errno.
+ */
+static inline int clk_drop_range(struct clk *clk)
+{
+ return clk_set_rate_range(clk, 0, ULONG_MAX);
+}
+
/**
* clk_get_optional - lookup and obtain a reference to an optional clock
* producer.
--
2.35.1
^ permalink raw reply related [flat|nested] 26+ messages in thread
* [PATCH v5 07/11] clk: bcm: rpi: Add variant structure
2022-02-22 13:18 ` Maxime Ripard
@ 2022-02-22 13:18 ` Maxime Ripard
-1 siblings, 0 replies; 26+ messages in thread
From: Maxime Ripard @ 2022-02-22 13:18 UTC (permalink / raw)
To: Mike Turquette, Stephen Boyd
Cc: dri-devel, linux-clk, Dave Stevenson, Phil Elwell, Tim Gover,
Dom Cobley, Maxime Ripard
We only export a bunch of firmware clocks, and some of them require
special treatment.
This has been do so far using some tests on the clock id in various
places, but this is fairly hard to extend and doesn't scale very well.
Since we'll need some more cases in the next patches, let's switch to a
variant structure that defines the behaviour we need to have for a given
clock.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
---
drivers/clk/bcm/clk-raspberrypi.c | 62 +++++++++++++++++++++++--------
1 file changed, 46 insertions(+), 16 deletions(-)
diff --git a/drivers/clk/bcm/clk-raspberrypi.c b/drivers/clk/bcm/clk-raspberrypi.c
index dd3b71eafabf..f7185d421085 100644
--- a/drivers/clk/bcm/clk-raspberrypi.c
+++ b/drivers/clk/bcm/clk-raspberrypi.c
@@ -56,6 +56,8 @@ static char *rpi_firmware_clk_names[] = {
#define RPI_FIRMWARE_STATE_ENABLE_BIT BIT(0)
#define RPI_FIRMWARE_STATE_WAIT_BIT BIT(1)
+struct raspberrypi_clk_variant;
+
struct raspberrypi_clk {
struct device *dev;
struct rpi_firmware *firmware;
@@ -66,10 +68,36 @@ struct raspberrypi_clk_data {
struct clk_hw hw;
unsigned int id;
+ struct raspberrypi_clk_variant *variant;
struct raspberrypi_clk *rpi;
};
+struct raspberrypi_clk_variant {
+ bool export;
+ char *clkdev;
+};
+
+static struct raspberrypi_clk_variant
+raspberrypi_clk_variants[RPI_FIRMWARE_NUM_CLK_ID] = {
+ [RPI_FIRMWARE_ARM_CLK_ID] = {
+ .export = true,
+ .clkdev = "cpu0",
+ },
+ [RPI_FIRMWARE_CORE_CLK_ID] = {
+ .export = true,
+ },
+ [RPI_FIRMWARE_M2MC_CLK_ID] = {
+ .export = true,
+ },
+ [RPI_FIRMWARE_V3D_CLK_ID] = {
+ .export = true,
+ },
+ [RPI_FIRMWARE_PIXEL_BVB_CLK_ID] = {
+ .export = true,
+ },
+};
+
/*
* Structure of the message passed to Raspberry Pi's firmware in order to
* change clock rates. The 'disable_turbo' option is only available to the ARM
@@ -183,7 +211,8 @@ static const struct clk_ops raspberrypi_firmware_clk_ops = {
static struct clk_hw *raspberrypi_clk_register(struct raspberrypi_clk *rpi,
unsigned int parent,
- unsigned int id)
+ unsigned int id,
+ struct raspberrypi_clk_variant *variant)
{
struct raspberrypi_clk_data *data;
struct clk_init_data init = {};
@@ -195,6 +224,7 @@ static struct clk_hw *raspberrypi_clk_register(struct raspberrypi_clk *rpi,
return ERR_PTR(-ENOMEM);
data->rpi = rpi;
data->id = id;
+ data->variant = variant;
init.name = devm_kasprintf(rpi->dev, GFP_KERNEL,
"fw-clk-%s",
@@ -228,9 +258,9 @@ static struct clk_hw *raspberrypi_clk_register(struct raspberrypi_clk *rpi,
clk_hw_set_rate_range(&data->hw, min_rate, max_rate);
- if (id == RPI_FIRMWARE_ARM_CLK_ID) {
+ if (variant->clkdev) {
ret = devm_clk_hw_register_clkdev(rpi->dev, &data->hw,
- NULL, "cpu0");
+ NULL, variant->clkdev);
if (ret) {
dev_err(rpi->dev, "Failed to initialize clkdev\n");
return ERR_PTR(ret);
@@ -264,27 +294,27 @@ static int raspberrypi_discover_clocks(struct raspberrypi_clk *rpi,
return ret;
while (clks->id) {
- struct clk_hw *hw;
+ struct raspberrypi_clk_variant *variant;
+
+ if (clks->id > RPI_FIRMWARE_NUM_CLK_ID) {
+ dev_err(rpi->dev, "Unknown clock id: %u", clks->id);
+ return -EINVAL;
+ }
+
+ variant = &raspberrypi_clk_variants[clks->id];
+ if (variant->export) {
+ struct clk_hw *hw;
- switch (clks->id) {
- case RPI_FIRMWARE_ARM_CLK_ID:
- case RPI_FIRMWARE_CORE_CLK_ID:
- case RPI_FIRMWARE_M2MC_CLK_ID:
- case RPI_FIRMWARE_V3D_CLK_ID:
- case RPI_FIRMWARE_PIXEL_BVB_CLK_ID:
hw = raspberrypi_clk_register(rpi, clks->parent,
- clks->id);
+ clks->id, variant);
if (IS_ERR(hw))
return PTR_ERR(hw);
data->hws[clks->id] = hw;
data->num = clks->id + 1;
- fallthrough;
-
- default:
- clks++;
- break;
}
+
+ clks++;
}
return 0;
--
2.35.1
^ permalink raw reply related [flat|nested] 26+ messages in thread
* [PATCH v5 07/11] clk: bcm: rpi: Add variant structure
@ 2022-02-22 13:18 ` Maxime Ripard
0 siblings, 0 replies; 26+ messages in thread
From: Maxime Ripard @ 2022-02-22 13:18 UTC (permalink / raw)
To: Mike Turquette, Stephen Boyd
Cc: Dom Cobley, Tim Gover, Dave Stevenson, dri-devel, linux-clk,
Maxime Ripard, Phil Elwell
We only export a bunch of firmware clocks, and some of them require
special treatment.
This has been do so far using some tests on the clock id in various
places, but this is fairly hard to extend and doesn't scale very well.
Since we'll need some more cases in the next patches, let's switch to a
variant structure that defines the behaviour we need to have for a given
clock.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
---
drivers/clk/bcm/clk-raspberrypi.c | 62 +++++++++++++++++++++++--------
1 file changed, 46 insertions(+), 16 deletions(-)
diff --git a/drivers/clk/bcm/clk-raspberrypi.c b/drivers/clk/bcm/clk-raspberrypi.c
index dd3b71eafabf..f7185d421085 100644
--- a/drivers/clk/bcm/clk-raspberrypi.c
+++ b/drivers/clk/bcm/clk-raspberrypi.c
@@ -56,6 +56,8 @@ static char *rpi_firmware_clk_names[] = {
#define RPI_FIRMWARE_STATE_ENABLE_BIT BIT(0)
#define RPI_FIRMWARE_STATE_WAIT_BIT BIT(1)
+struct raspberrypi_clk_variant;
+
struct raspberrypi_clk {
struct device *dev;
struct rpi_firmware *firmware;
@@ -66,10 +68,36 @@ struct raspberrypi_clk_data {
struct clk_hw hw;
unsigned int id;
+ struct raspberrypi_clk_variant *variant;
struct raspberrypi_clk *rpi;
};
+struct raspberrypi_clk_variant {
+ bool export;
+ char *clkdev;
+};
+
+static struct raspberrypi_clk_variant
+raspberrypi_clk_variants[RPI_FIRMWARE_NUM_CLK_ID] = {
+ [RPI_FIRMWARE_ARM_CLK_ID] = {
+ .export = true,
+ .clkdev = "cpu0",
+ },
+ [RPI_FIRMWARE_CORE_CLK_ID] = {
+ .export = true,
+ },
+ [RPI_FIRMWARE_M2MC_CLK_ID] = {
+ .export = true,
+ },
+ [RPI_FIRMWARE_V3D_CLK_ID] = {
+ .export = true,
+ },
+ [RPI_FIRMWARE_PIXEL_BVB_CLK_ID] = {
+ .export = true,
+ },
+};
+
/*
* Structure of the message passed to Raspberry Pi's firmware in order to
* change clock rates. The 'disable_turbo' option is only available to the ARM
@@ -183,7 +211,8 @@ static const struct clk_ops raspberrypi_firmware_clk_ops = {
static struct clk_hw *raspberrypi_clk_register(struct raspberrypi_clk *rpi,
unsigned int parent,
- unsigned int id)
+ unsigned int id,
+ struct raspberrypi_clk_variant *variant)
{
struct raspberrypi_clk_data *data;
struct clk_init_data init = {};
@@ -195,6 +224,7 @@ static struct clk_hw *raspberrypi_clk_register(struct raspberrypi_clk *rpi,
return ERR_PTR(-ENOMEM);
data->rpi = rpi;
data->id = id;
+ data->variant = variant;
init.name = devm_kasprintf(rpi->dev, GFP_KERNEL,
"fw-clk-%s",
@@ -228,9 +258,9 @@ static struct clk_hw *raspberrypi_clk_register(struct raspberrypi_clk *rpi,
clk_hw_set_rate_range(&data->hw, min_rate, max_rate);
- if (id == RPI_FIRMWARE_ARM_CLK_ID) {
+ if (variant->clkdev) {
ret = devm_clk_hw_register_clkdev(rpi->dev, &data->hw,
- NULL, "cpu0");
+ NULL, variant->clkdev);
if (ret) {
dev_err(rpi->dev, "Failed to initialize clkdev\n");
return ERR_PTR(ret);
@@ -264,27 +294,27 @@ static int raspberrypi_discover_clocks(struct raspberrypi_clk *rpi,
return ret;
while (clks->id) {
- struct clk_hw *hw;
+ struct raspberrypi_clk_variant *variant;
+
+ if (clks->id > RPI_FIRMWARE_NUM_CLK_ID) {
+ dev_err(rpi->dev, "Unknown clock id: %u", clks->id);
+ return -EINVAL;
+ }
+
+ variant = &raspberrypi_clk_variants[clks->id];
+ if (variant->export) {
+ struct clk_hw *hw;
- switch (clks->id) {
- case RPI_FIRMWARE_ARM_CLK_ID:
- case RPI_FIRMWARE_CORE_CLK_ID:
- case RPI_FIRMWARE_M2MC_CLK_ID:
- case RPI_FIRMWARE_V3D_CLK_ID:
- case RPI_FIRMWARE_PIXEL_BVB_CLK_ID:
hw = raspberrypi_clk_register(rpi, clks->parent,
- clks->id);
+ clks->id, variant);
if (IS_ERR(hw))
return PTR_ERR(hw);
data->hws[clks->id] = hw;
data->num = clks->id + 1;
- fallthrough;
-
- default:
- clks++;
- break;
}
+
+ clks++;
}
return 0;
--
2.35.1
^ permalink raw reply related [flat|nested] 26+ messages in thread
* [PATCH v5 08/11] clk: bcm: rpi: Set a default minimum rate
2022-02-22 13:18 ` Maxime Ripard
@ 2022-02-22 13:18 ` Maxime Ripard
-1 siblings, 0 replies; 26+ messages in thread
From: Maxime Ripard @ 2022-02-22 13:18 UTC (permalink / raw)
To: Mike Turquette, Stephen Boyd
Cc: dri-devel, linux-clk, Dave Stevenson, Phil Elwell, Tim Gover,
Dom Cobley, Maxime Ripard
The M2MC clock provides the state machine clock for both HDMI
controllers.
However, if no HDMI monitor is plugged in at boot, its clock rate will
be left at 0 by the firmware and will make any register access end up in
a CPU stall, even though the clock was enabled.
We had some code in the HDMI controller to deal with this before, but it
makes more sense to have it in the clock driver. Move it there.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
---
drivers/clk/bcm/clk-raspberrypi.c | 26 ++++++++++++++++++++++++++
1 file changed, 26 insertions(+)
diff --git a/drivers/clk/bcm/clk-raspberrypi.c b/drivers/clk/bcm/clk-raspberrypi.c
index f7185d421085..c879f2e9a4a7 100644
--- a/drivers/clk/bcm/clk-raspberrypi.c
+++ b/drivers/clk/bcm/clk-raspberrypi.c
@@ -76,6 +76,7 @@ struct raspberrypi_clk_data {
struct raspberrypi_clk_variant {
bool export;
char *clkdev;
+ unsigned long min_rate;
};
static struct raspberrypi_clk_variant
@@ -89,6 +90,18 @@ raspberrypi_clk_variants[RPI_FIRMWARE_NUM_CLK_ID] = {
},
[RPI_FIRMWARE_M2MC_CLK_ID] = {
.export = true,
+
+ /*
+ * If we boot without any cable connected to any of the
+ * HDMI connector, the firmware will skip the HSM
+ * initialization and leave it with a rate of 0,
+ * resulting in a bus lockup when we're accessing the
+ * registers even if it's enabled.
+ *
+ * Let's put a sensible default so that we don't end up
+ * in this situation.
+ */
+ .min_rate = 120000000,
},
[RPI_FIRMWARE_V3D_CLK_ID] = {
.export = true,
@@ -267,6 +280,19 @@ static struct clk_hw *raspberrypi_clk_register(struct raspberrypi_clk *rpi,
}
}
+ if (variant->min_rate) {
+ unsigned long rate;
+
+ clk_hw_set_rate_range(&data->hw, variant->min_rate, max_rate);
+
+ rate = raspberrypi_fw_get_rate(&data->hw, 0);
+ if (rate < variant->min_rate) {
+ ret = raspberrypi_fw_set_rate(&data->hw, variant->min_rate, 0);
+ if (ret)
+ return ERR_PTR(ret);
+ }
+ }
+
return &data->hw;
}
--
2.35.1
^ permalink raw reply related [flat|nested] 26+ messages in thread
* [PATCH v5 08/11] clk: bcm: rpi: Set a default minimum rate
@ 2022-02-22 13:18 ` Maxime Ripard
0 siblings, 0 replies; 26+ messages in thread
From: Maxime Ripard @ 2022-02-22 13:18 UTC (permalink / raw)
To: Mike Turquette, Stephen Boyd
Cc: Dom Cobley, Tim Gover, Dave Stevenson, dri-devel, linux-clk,
Maxime Ripard, Phil Elwell
The M2MC clock provides the state machine clock for both HDMI
controllers.
However, if no HDMI monitor is plugged in at boot, its clock rate will
be left at 0 by the firmware and will make any register access end up in
a CPU stall, even though the clock was enabled.
We had some code in the HDMI controller to deal with this before, but it
makes more sense to have it in the clock driver. Move it there.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
---
drivers/clk/bcm/clk-raspberrypi.c | 26 ++++++++++++++++++++++++++
1 file changed, 26 insertions(+)
diff --git a/drivers/clk/bcm/clk-raspberrypi.c b/drivers/clk/bcm/clk-raspberrypi.c
index f7185d421085..c879f2e9a4a7 100644
--- a/drivers/clk/bcm/clk-raspberrypi.c
+++ b/drivers/clk/bcm/clk-raspberrypi.c
@@ -76,6 +76,7 @@ struct raspberrypi_clk_data {
struct raspberrypi_clk_variant {
bool export;
char *clkdev;
+ unsigned long min_rate;
};
static struct raspberrypi_clk_variant
@@ -89,6 +90,18 @@ raspberrypi_clk_variants[RPI_FIRMWARE_NUM_CLK_ID] = {
},
[RPI_FIRMWARE_M2MC_CLK_ID] = {
.export = true,
+
+ /*
+ * If we boot without any cable connected to any of the
+ * HDMI connector, the firmware will skip the HSM
+ * initialization and leave it with a rate of 0,
+ * resulting in a bus lockup when we're accessing the
+ * registers even if it's enabled.
+ *
+ * Let's put a sensible default so that we don't end up
+ * in this situation.
+ */
+ .min_rate = 120000000,
},
[RPI_FIRMWARE_V3D_CLK_ID] = {
.export = true,
@@ -267,6 +280,19 @@ static struct clk_hw *raspberrypi_clk_register(struct raspberrypi_clk *rpi,
}
}
+ if (variant->min_rate) {
+ unsigned long rate;
+
+ clk_hw_set_rate_range(&data->hw, variant->min_rate, max_rate);
+
+ rate = raspberrypi_fw_get_rate(&data->hw, 0);
+ if (rate < variant->min_rate) {
+ ret = raspberrypi_fw_set_rate(&data->hw, variant->min_rate, 0);
+ if (ret)
+ return ERR_PTR(ret);
+ }
+ }
+
return &data->hw;
}
--
2.35.1
^ permalink raw reply related [flat|nested] 26+ messages in thread
* [PATCH v5 09/11] clk: bcm: rpi: Run some clocks at the minimum rate allowed
2022-02-22 13:18 ` Maxime Ripard
@ 2022-02-22 13:18 ` Maxime Ripard
-1 siblings, 0 replies; 26+ messages in thread
From: Maxime Ripard @ 2022-02-22 13:18 UTC (permalink / raw)
To: Mike Turquette, Stephen Boyd
Cc: dri-devel, linux-clk, Dave Stevenson, Phil Elwell, Tim Gover,
Dom Cobley, Maxime Ripard
The core clock and M2MC clocks are shared between some devices (Unicam
controllers and the HVS, and the HDMI controllers, respectively) that
will have various, varying, requirements depending on their current work
load.
Since those loads can require a fairly high clock rate in extreme
conditions (up to ~600MHz), we can end up running those clocks at their
maximum frequency even though we no longer require such a high rate.
Fortunately, those devices don't require an exact rate but a minimum
rate, and all the drivers are using clk_set_min_rate. Thus, we can just
rely on the fact that the clk_request minimum (which is the aggregated
minimum of all the clock users) is what we want at all times.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
---
drivers/clk/bcm/clk-raspberrypi.c | 37 +++++++++++++++++++++++++++++++
1 file changed, 37 insertions(+)
diff --git a/drivers/clk/bcm/clk-raspberrypi.c b/drivers/clk/bcm/clk-raspberrypi.c
index c879f2e9a4a7..9d09621549b9 100644
--- a/drivers/clk/bcm/clk-raspberrypi.c
+++ b/drivers/clk/bcm/clk-raspberrypi.c
@@ -77,6 +77,7 @@ struct raspberrypi_clk_variant {
bool export;
char *clkdev;
unsigned long min_rate;
+ bool minimize;
};
static struct raspberrypi_clk_variant
@@ -87,6 +88,18 @@ raspberrypi_clk_variants[RPI_FIRMWARE_NUM_CLK_ID] = {
},
[RPI_FIRMWARE_CORE_CLK_ID] = {
.export = true,
+
+ /*
+ * The clock is shared between the HVS and the CSI
+ * controllers, on the BCM2711 and will change depending
+ * on the pixels composited on the HVS and the capture
+ * resolution on Unicam.
+ *
+ * Since the rate can get quite large, and we need to
+ * coordinate between both driver instances, let's
+ * always use the minimum the drivers will let us.
+ */
+ .minimize = true,
},
[RPI_FIRMWARE_M2MC_CLK_ID] = {
.export = true,
@@ -102,6 +115,16 @@ raspberrypi_clk_variants[RPI_FIRMWARE_NUM_CLK_ID] = {
* in this situation.
*/
.min_rate = 120000000,
+
+ /*
+ * The clock is shared between the two HDMI controllers
+ * on the BCM2711 and will change depending on the
+ * resolution output on each. Since the rate can get
+ * quite large, and we need to coordinate between both
+ * driver instances, let's always use the minimum the
+ * drivers will let us.
+ */
+ .minimize = true,
},
[RPI_FIRMWARE_V3D_CLK_ID] = {
.export = true,
@@ -206,12 +229,26 @@ static int raspberrypi_fw_set_rate(struct clk_hw *hw, unsigned long rate,
static int raspberrypi_fw_dumb_determine_rate(struct clk_hw *hw,
struct clk_rate_request *req)
{
+ struct raspberrypi_clk_data *data =
+ container_of(hw, struct raspberrypi_clk_data, hw);
+ struct raspberrypi_clk_variant *variant = data->variant;
+
/*
* The firmware will do the rounding but that isn't part of
* the interface with the firmware, so we just do our best
* here.
*/
+
req->rate = clamp(req->rate, req->min_rate, req->max_rate);
+
+ /*
+ * We want to aggressively reduce the clock rate here, so let's
+ * just ignore the requested rate and return the bare minimum
+ * rate we can get away with.
+ */
+ if (variant->minimize && req->min_rate > 0)
+ req->rate = req->min_rate;
+
return 0;
}
--
2.35.1
^ permalink raw reply related [flat|nested] 26+ messages in thread
* [PATCH v5 09/11] clk: bcm: rpi: Run some clocks at the minimum rate allowed
@ 2022-02-22 13:18 ` Maxime Ripard
0 siblings, 0 replies; 26+ messages in thread
From: Maxime Ripard @ 2022-02-22 13:18 UTC (permalink / raw)
To: Mike Turquette, Stephen Boyd
Cc: Dom Cobley, Tim Gover, Dave Stevenson, dri-devel, linux-clk,
Maxime Ripard, Phil Elwell
The core clock and M2MC clocks are shared between some devices (Unicam
controllers and the HVS, and the HDMI controllers, respectively) that
will have various, varying, requirements depending on their current work
load.
Since those loads can require a fairly high clock rate in extreme
conditions (up to ~600MHz), we can end up running those clocks at their
maximum frequency even though we no longer require such a high rate.
Fortunately, those devices don't require an exact rate but a minimum
rate, and all the drivers are using clk_set_min_rate. Thus, we can just
rely on the fact that the clk_request minimum (which is the aggregated
minimum of all the clock users) is what we want at all times.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
---
drivers/clk/bcm/clk-raspberrypi.c | 37 +++++++++++++++++++++++++++++++
1 file changed, 37 insertions(+)
diff --git a/drivers/clk/bcm/clk-raspberrypi.c b/drivers/clk/bcm/clk-raspberrypi.c
index c879f2e9a4a7..9d09621549b9 100644
--- a/drivers/clk/bcm/clk-raspberrypi.c
+++ b/drivers/clk/bcm/clk-raspberrypi.c
@@ -77,6 +77,7 @@ struct raspberrypi_clk_variant {
bool export;
char *clkdev;
unsigned long min_rate;
+ bool minimize;
};
static struct raspberrypi_clk_variant
@@ -87,6 +88,18 @@ raspberrypi_clk_variants[RPI_FIRMWARE_NUM_CLK_ID] = {
},
[RPI_FIRMWARE_CORE_CLK_ID] = {
.export = true,
+
+ /*
+ * The clock is shared between the HVS and the CSI
+ * controllers, on the BCM2711 and will change depending
+ * on the pixels composited on the HVS and the capture
+ * resolution on Unicam.
+ *
+ * Since the rate can get quite large, and we need to
+ * coordinate between both driver instances, let's
+ * always use the minimum the drivers will let us.
+ */
+ .minimize = true,
},
[RPI_FIRMWARE_M2MC_CLK_ID] = {
.export = true,
@@ -102,6 +115,16 @@ raspberrypi_clk_variants[RPI_FIRMWARE_NUM_CLK_ID] = {
* in this situation.
*/
.min_rate = 120000000,
+
+ /*
+ * The clock is shared between the two HDMI controllers
+ * on the BCM2711 and will change depending on the
+ * resolution output on each. Since the rate can get
+ * quite large, and we need to coordinate between both
+ * driver instances, let's always use the minimum the
+ * drivers will let us.
+ */
+ .minimize = true,
},
[RPI_FIRMWARE_V3D_CLK_ID] = {
.export = true,
@@ -206,12 +229,26 @@ static int raspberrypi_fw_set_rate(struct clk_hw *hw, unsigned long rate,
static int raspberrypi_fw_dumb_determine_rate(struct clk_hw *hw,
struct clk_rate_request *req)
{
+ struct raspberrypi_clk_data *data =
+ container_of(hw, struct raspberrypi_clk_data, hw);
+ struct raspberrypi_clk_variant *variant = data->variant;
+
/*
* The firmware will do the rounding but that isn't part of
* the interface with the firmware, so we just do our best
* here.
*/
+
req->rate = clamp(req->rate, req->min_rate, req->max_rate);
+
+ /*
+ * We want to aggressively reduce the clock rate here, so let's
+ * just ignore the requested rate and return the bare minimum
+ * rate we can get away with.
+ */
+ if (variant->minimize && req->min_rate > 0)
+ req->rate = req->min_rate;
+
return 0;
}
--
2.35.1
^ permalink raw reply related [flat|nested] 26+ messages in thread
* [PATCH v5 10/11] drm/vc4: Add logging and comments
2022-02-22 13:18 ` Maxime Ripard
@ 2022-02-22 13:18 ` Maxime Ripard
-1 siblings, 0 replies; 26+ messages in thread
From: Maxime Ripard @ 2022-02-22 13:18 UTC (permalink / raw)
To: Mike Turquette, Stephen Boyd
Cc: dri-devel, linux-clk, Dave Stevenson, Phil Elwell, Tim Gover,
Dom Cobley, Maxime Ripard
The HVS core clock isn't really obvious, so let's add a bunch more
comments and some logging for easier debugging.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
---
drivers/gpu/drm/vc4/vc4_kms.c | 11 +++++++++++
1 file changed, 11 insertions(+)
diff --git a/drivers/gpu/drm/vc4/vc4_kms.c b/drivers/gpu/drm/vc4/vc4_kms.c
index 24de29bc1cda..6fe03fc17d73 100644
--- a/drivers/gpu/drm/vc4/vc4_kms.c
+++ b/drivers/gpu/drm/vc4/vc4_kms.c
@@ -389,8 +389,15 @@ static void vc4_atomic_commit_tail(struct drm_atomic_state *state)
500000000,
new_hvs_state->core_clock_rate);
+ drm_dbg(dev, "Raising the core clock at %lu Hz\n", core_rate);
+
+ /*
+ * Do a temporary request on the core clock during the
+ * modeset.
+ */
clk_set_min_rate(hvs->core_clk, core_rate);
}
+
drm_atomic_helper_commit_modeset_disables(dev, state);
vc4_ctm_commit(vc4, state);
@@ -416,6 +423,10 @@ static void vc4_atomic_commit_tail(struct drm_atomic_state *state)
drm_dbg(dev, "Running the core clock at %lu Hz\n",
new_hvs_state->core_clock_rate);
+ /*
+ * Request a clock rate based on the current HVS
+ * requirements.
+ */
clk_set_min_rate(hvs->core_clk, new_hvs_state->core_clock_rate);
}
}
--
2.35.1
^ permalink raw reply related [flat|nested] 26+ messages in thread
* [PATCH v5 10/11] drm/vc4: Add logging and comments
@ 2022-02-22 13:18 ` Maxime Ripard
0 siblings, 0 replies; 26+ messages in thread
From: Maxime Ripard @ 2022-02-22 13:18 UTC (permalink / raw)
To: Mike Turquette, Stephen Boyd
Cc: Dom Cobley, Tim Gover, Dave Stevenson, dri-devel, linux-clk,
Maxime Ripard, Phil Elwell
The HVS core clock isn't really obvious, so let's add a bunch more
comments and some logging for easier debugging.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
---
drivers/gpu/drm/vc4/vc4_kms.c | 11 +++++++++++
1 file changed, 11 insertions(+)
diff --git a/drivers/gpu/drm/vc4/vc4_kms.c b/drivers/gpu/drm/vc4/vc4_kms.c
index 24de29bc1cda..6fe03fc17d73 100644
--- a/drivers/gpu/drm/vc4/vc4_kms.c
+++ b/drivers/gpu/drm/vc4/vc4_kms.c
@@ -389,8 +389,15 @@ static void vc4_atomic_commit_tail(struct drm_atomic_state *state)
500000000,
new_hvs_state->core_clock_rate);
+ drm_dbg(dev, "Raising the core clock at %lu Hz\n", core_rate);
+
+ /*
+ * Do a temporary request on the core clock during the
+ * modeset.
+ */
clk_set_min_rate(hvs->core_clk, core_rate);
}
+
drm_atomic_helper_commit_modeset_disables(dev, state);
vc4_ctm_commit(vc4, state);
@@ -416,6 +423,10 @@ static void vc4_atomic_commit_tail(struct drm_atomic_state *state)
drm_dbg(dev, "Running the core clock at %lu Hz\n",
new_hvs_state->core_clock_rate);
+ /*
+ * Request a clock rate based on the current HVS
+ * requirements.
+ */
clk_set_min_rate(hvs->core_clk, new_hvs_state->core_clock_rate);
}
}
--
2.35.1
^ permalink raw reply related [flat|nested] 26+ messages in thread
* [PATCH v5 11/11] drm/vc4: hdmi: Remove clock rate initialization
2022-02-22 13:18 ` Maxime Ripard
@ 2022-02-22 13:18 ` Maxime Ripard
-1 siblings, 0 replies; 26+ messages in thread
From: Maxime Ripard @ 2022-02-22 13:18 UTC (permalink / raw)
To: Mike Turquette, Stephen Boyd
Cc: dri-devel, linux-clk, Dave Stevenson, Phil Elwell, Tim Gover,
Dom Cobley, Maxime Ripard
Now that the clock driver makes sure we never end up with a rate of 0,
the HDMI driver doesn't need to care anymore.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
---
drivers/gpu/drm/vc4/vc4_hdmi.c | 13 -------------
1 file changed, 13 deletions(-)
diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c
index 92b1530aa17b..21aff3ad96cf 100644
--- a/drivers/gpu/drm/vc4/vc4_hdmi.c
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
@@ -2576,19 +2576,6 @@ static int vc4_hdmi_bind(struct device *dev, struct device *master, void *data)
vc4_hdmi->disable_4kp60 = true;
}
- /*
- * If we boot without any cable connected to the HDMI connector,
- * the firmware will skip the HSM initialization and leave it
- * with a rate of 0, resulting in a bus lockup when we're
- * accessing the registers even if it's enabled.
- *
- * Let's put a sensible default at runtime_resume so that we
- * don't end up in this situation.
- */
- ret = clk_set_min_rate(vc4_hdmi->hsm_clock, HSM_MIN_CLOCK_FREQ);
- if (ret)
- goto err_put_ddc;
-
/*
* We need to have the device powered up at this point to call
* our reset hook and for the CEC init.
--
2.35.1
^ permalink raw reply related [flat|nested] 26+ messages in thread
* [PATCH v5 11/11] drm/vc4: hdmi: Remove clock rate initialization
@ 2022-02-22 13:18 ` Maxime Ripard
0 siblings, 0 replies; 26+ messages in thread
From: Maxime Ripard @ 2022-02-22 13:18 UTC (permalink / raw)
To: Mike Turquette, Stephen Boyd
Cc: Dom Cobley, Tim Gover, Dave Stevenson, dri-devel, linux-clk,
Maxime Ripard, Phil Elwell
Now that the clock driver makes sure we never end up with a rate of 0,
the HDMI driver doesn't need to care anymore.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
---
drivers/gpu/drm/vc4/vc4_hdmi.c | 13 -------------
1 file changed, 13 deletions(-)
diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c
index 92b1530aa17b..21aff3ad96cf 100644
--- a/drivers/gpu/drm/vc4/vc4_hdmi.c
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
@@ -2576,19 +2576,6 @@ static int vc4_hdmi_bind(struct device *dev, struct device *master, void *data)
vc4_hdmi->disable_4kp60 = true;
}
- /*
- * If we boot without any cable connected to the HDMI connector,
- * the firmware will skip the HSM initialization and leave it
- * with a rate of 0, resulting in a bus lockup when we're
- * accessing the registers even if it's enabled.
- *
- * Let's put a sensible default at runtime_resume so that we
- * don't end up in this situation.
- */
- ret = clk_set_min_rate(vc4_hdmi->hsm_clock, HSM_MIN_CLOCK_FREQ);
- if (ret)
- goto err_put_ddc;
-
/*
* We need to have the device powered up at this point to call
* our reset hook and for the CEC init.
--
2.35.1
^ permalink raw reply related [flat|nested] 26+ messages in thread
* Re: [PATCH v5 01/11] clk: Introduce Kunit Tests for the framework
2022-02-22 13:18 ` Maxime Ripard
@ 2022-02-23 2:25 ` kernel test robot
-1 siblings, 0 replies; 26+ messages in thread
From: kernel test robot @ 2022-02-23 2:25 UTC (permalink / raw)
To: Maxime Ripard, Mike Turquette, Stephen Boyd
Cc: kbuild-all, dri-devel, linux-clk, Dave Stevenson, Phil Elwell,
Tim Gover, Dom Cobley, Maxime Ripard, kunit-dev
Hi Maxime,
I love your patch! Yet something to improve:
[auto build test ERROR on clk/clk-next]
[also build test ERROR on next-20220217]
[cannot apply to drm-intel/for-linux-next drm-tip/drm-tip drm-exynos/exynos-drm-next drm/drm-next tegra-drm/drm/tegra/for-next linus/master airlied/drm-next v5.17-rc5]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/0day-ci/linux/commits/Maxime-Ripard/clk-Improve-clock-range-handling/20220222-212043
base: https://git.kernel.org/pub/scm/linux/kernel/git/clk/linux.git clk-next
config: mips-allmodconfig (https://download.01.org/0day-ci/archive/20220223/202202231024.8SBLRlyr-lkp@intel.com/config)
compiler: mips-linux-gcc (GCC) 11.2.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/0day-ci/linux/commit/377d67441dca4a3d5df1d3b5a5b63c9a29f9b8b0
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Maxime-Ripard/clk-Improve-clock-range-handling/20220222-212043
git checkout 377d67441dca4a3d5df1d3b5a5b63c9a29f9b8b0
# save the config file to linux build tree
mkdir build_dir
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross O=build_dir ARCH=mips SHELL=/bin/bash
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
All errors (new ones prefixed by >>, old ones prefixed by <<):
>> ERROR: modpost: "clk_hw_create_clk" [drivers/clk/clk_test.ko] undefined!
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
^ permalink raw reply [flat|nested] 26+ messages in thread
* Re: [PATCH v5 01/11] clk: Introduce Kunit Tests for the framework
@ 2022-02-23 2:25 ` kernel test robot
0 siblings, 0 replies; 26+ messages in thread
From: kernel test robot @ 2022-02-23 2:25 UTC (permalink / raw)
To: Maxime Ripard, Mike Turquette, Stephen Boyd
Cc: kbuild-all, Dom Cobley, Tim Gover, Dave Stevenson, dri-devel,
linux-clk, Maxime Ripard, Phil Elwell, kunit-dev
Hi Maxime,
I love your patch! Yet something to improve:
[auto build test ERROR on clk/clk-next]
[also build test ERROR on next-20220217]
[cannot apply to drm-intel/for-linux-next drm-tip/drm-tip drm-exynos/exynos-drm-next drm/drm-next tegra-drm/drm/tegra/for-next linus/master airlied/drm-next v5.17-rc5]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/0day-ci/linux/commits/Maxime-Ripard/clk-Improve-clock-range-handling/20220222-212043
base: https://git.kernel.org/pub/scm/linux/kernel/git/clk/linux.git clk-next
config: mips-allmodconfig (https://download.01.org/0day-ci/archive/20220223/202202231024.8SBLRlyr-lkp@intel.com/config)
compiler: mips-linux-gcc (GCC) 11.2.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/0day-ci/linux/commit/377d67441dca4a3d5df1d3b5a5b63c9a29f9b8b0
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Maxime-Ripard/clk-Improve-clock-range-handling/20220222-212043
git checkout 377d67441dca4a3d5df1d3b5a5b63c9a29f9b8b0
# save the config file to linux build tree
mkdir build_dir
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross O=build_dir ARCH=mips SHELL=/bin/bash
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
All errors (new ones prefixed by >>, old ones prefixed by <<):
>> ERROR: modpost: "clk_hw_create_clk" [drivers/clk/clk_test.ko] undefined!
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
^ permalink raw reply [flat|nested] 26+ messages in thread
end of thread, other threads:[~2022-02-23 2:26 UTC | newest]
Thread overview: 26+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-02-22 13:18 [PATCH v5 00/11] clk: Improve clock range handling Maxime Ripard
2022-02-22 13:18 ` Maxime Ripard
2022-02-22 13:18 ` [PATCH v5 01/11] clk: Introduce Kunit Tests for the framework Maxime Ripard
2022-02-22 13:18 ` Maxime Ripard
2022-02-23 2:25 ` kernel test robot
2022-02-23 2:25 ` kernel test robot
2022-02-22 13:18 ` [PATCH v5 02/11] clk: Enforce that disjoints limits are invalid Maxime Ripard
2022-02-22 13:18 ` Maxime Ripard
2022-02-22 13:18 ` [PATCH v5 03/11] clk: Always clamp the rounded rate Maxime Ripard
2022-02-22 13:18 ` Maxime Ripard
2022-02-22 13:18 ` [PATCH v5 04/11] clk: Use clamp instead of open-coding our own Maxime Ripard
2022-02-22 13:18 ` Maxime Ripard
2022-02-22 13:18 ` [PATCH v5 05/11] clk: Always set the rate on clk_set_range_rate Maxime Ripard
2022-02-22 13:18 ` Maxime Ripard
2022-02-22 13:18 ` [PATCH v5 06/11] clk: Add clk_drop_range Maxime Ripard
2022-02-22 13:18 ` Maxime Ripard
2022-02-22 13:18 ` [PATCH v5 07/11] clk: bcm: rpi: Add variant structure Maxime Ripard
2022-02-22 13:18 ` Maxime Ripard
2022-02-22 13:18 ` [PATCH v5 08/11] clk: bcm: rpi: Set a default minimum rate Maxime Ripard
2022-02-22 13:18 ` Maxime Ripard
2022-02-22 13:18 ` [PATCH v5 09/11] clk: bcm: rpi: Run some clocks at the minimum rate allowed Maxime Ripard
2022-02-22 13:18 ` Maxime Ripard
2022-02-22 13:18 ` [PATCH v5 10/11] drm/vc4: Add logging and comments Maxime Ripard
2022-02-22 13:18 ` Maxime Ripard
2022-02-22 13:18 ` [PATCH v5 11/11] drm/vc4: hdmi: Remove clock rate initialization Maxime Ripard
2022-02-22 13:18 ` Maxime Ripard
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