diff mbox series

[6/6] of: Add KUnit test to confirm DTB is loaded

Message ID 20240112200750.4062441-7-sboyd@kernel.org
State New
Headers show
Series of: populate of_root node if bootloader doesn't | expand

Commit Message

Stephen Boyd Jan. 12, 2024, 8:07 p.m. UTC
Add a KUnit test that confirms a DTB has been loaded, i.e. there is a
root node, and that the of_have_populated_dt() API works properly.

Cc: Rob Herring <robh+dt@kernel.org>
Cc: Frank Rowand <frowand.list@gmail.com>
Cc: David Gow <davidgow@google.com>
Cc: Brendan Higgins <brendan.higgins@linux.dev>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
---
 drivers/of/.kunitconfig |  3 ++
 drivers/of/Kconfig      |  9 ++++
 drivers/of/Makefile     |  2 +
 drivers/of/of_test.c    | 98 +++++++++++++++++++++++++++++++++++++++++
 4 files changed, 112 insertions(+)
 create mode 100644 drivers/of/.kunitconfig
 create mode 100644 drivers/of/of_test.c

Comments

David Gow Jan. 16, 2024, 5:03 a.m. UTC | #1
On Sat, 13 Jan 2024 at 04:07, Stephen Boyd <sboyd@kernel.org> wrote:
>
> Add a KUnit test that confirms a DTB has been loaded, i.e. there is a
> root node, and that the of_have_populated_dt() API works properly.
>
> Cc: Rob Herring <robh+dt@kernel.org>
> Cc: Frank Rowand <frowand.list@gmail.com>
> Cc: David Gow <davidgow@google.com>
> Cc: Brendan Higgins <brendan.higgins@linux.dev>
> Signed-off-by: Stephen Boyd <sboyd@kernel.org>
> ---

I won't pretend to be a devicetree expert, but this looks good to me
from a KUnit point of view, and passes comfortably here.

checkpatch seems to have one complaint about the kconfig help text.
Personally, I think the brief description is fine.

Reviewed-by: David Gow <davidgow@google.com>

Cheers,
-- David

>  drivers/of/.kunitconfig |  3 ++
>  drivers/of/Kconfig      |  9 ++++
>  drivers/of/Makefile     |  2 +
>  drivers/of/of_test.c    | 98 +++++++++++++++++++++++++++++++++++++++++
>  4 files changed, 112 insertions(+)
>  create mode 100644 drivers/of/.kunitconfig
>  create mode 100644 drivers/of/of_test.c
>
> diff --git a/drivers/of/.kunitconfig b/drivers/of/.kunitconfig
> new file mode 100644
> index 000000000000..5a8fee11978c
> --- /dev/null
> +++ b/drivers/of/.kunitconfig
> @@ -0,0 +1,3 @@
> +CONFIG_KUNIT=y
> +CONFIG_OF=y
> +CONFIG_OF_KUNIT_TEST=y
> diff --git a/drivers/of/Kconfig b/drivers/of/Kconfig
> index 9628e48baa15..a527ba8451d9 100644
> --- a/drivers/of/Kconfig
> +++ b/drivers/of/Kconfig
> @@ -37,6 +37,15 @@ config OF_UNITTEST
>
>           If unsure, say N here. This option is not safe to enable.
>
> +config OF_KUNIT_TEST
> +       tristate "Devicetree KUnit DTB Test" if !KUNIT_ALL_TESTS
> +       depends on KUNIT
> +       default KUNIT_ALL_TESTS
> +       help
> +         This option builds KUnit unit tests for device tree infrastructure.
> +
> +         If unsure, say N here, but this option is safe to enable.
> +

FYI:
WARNING: please write a help paragraph that fully describes the config symbol
#111: FILE: drivers/of/Kconfig:40:

>  config OF_ALL_DTBS
>         bool "Build all Device Tree Blobs"
>         depends on COMPILE_TEST
> diff --git a/drivers/of/Makefile b/drivers/of/Makefile
> index df305348d1cb..251d33532148 100644
> --- a/drivers/of/Makefile
> +++ b/drivers/of/Makefile
> @@ -19,4 +19,6 @@ obj-y += kexec.o
>  endif
>  endif
>
> +obj-$(CONFIG_OF_KUNIT_TEST) += of_test.o
> +
>  obj-$(CONFIG_OF_UNITTEST) += unittest-data/
> diff --git a/drivers/of/of_test.c b/drivers/of/of_test.c
> new file mode 100644
> index 000000000000..7609ad3081b9
> --- /dev/null
> +++ b/drivers/of/of_test.c
> @@ -0,0 +1,98 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * KUnit tests for OF APIs
> + */
> +#include <linux/module.h>
> +#include <linux/of.h>
> +
> +#include <kunit/test.h>
> +
> +/*
> + * Test that the root node "/" exists.
> + */
> +static void dtb_root_node_found_by_path(struct kunit *test)
> +{
> +       struct device_node *np;
> +
> +       np = of_find_node_by_path("/");
> +       KUNIT_EXPECT_NOT_ERR_OR_NULL(test, np);
> +       of_node_put(np);
> +}
> +
> +/*
> + * Test that the of_root global variable is always populated when DT
> + * code is enabled.
> + */
> +static void dtb_root_node_populates_of_root(struct kunit *test)
> +{
> +       KUNIT_EXPECT_NOT_ERR_OR_NULL(test, of_root);
> +}
> +
> +static struct kunit_case dtb_test_cases[] = {
> +       KUNIT_CASE(dtb_root_node_found_by_path),
> +       KUNIT_CASE(dtb_root_node_populates_of_root),
> +       {}
> +};
> +
> +/*
> + * Test suite to confirm a live DTB is loaded.
> + */
> +static struct kunit_suite dtb_suite = {
> +       .name = "dtb",
> +       .test_cases = dtb_test_cases,
> +};
> +
> +/*
> + * Test that calling of_have_populated_dt() returns false when
> + * the OF_EMPTY_ROOT flag isn't set.
> + */
> +static void of_have_populated_dt_false_when_flag_set(struct kunit *test)
> +{
> +       bool was_set;
> +
> +       KUNIT_ASSERT_NOT_ERR_OR_NULL(test, of_root);
> +
> +       was_set = of_node_test_and_set_flag(of_root, OF_EMPTY_ROOT);
> +       KUNIT_EXPECT_FALSE(test, of_have_populated_dt());
> +
> +       if (!was_set)
> +               of_node_clear_flag(of_root, OF_EMPTY_ROOT);
> +}
> +
> +/*
> + * Test that calling of_have_populated_dt() returns false when
> + * the OF_EMPTY_ROOT flag isn't set.
> + */
> +static void of_have_populated_dt_true_when_flag_clear(struct kunit *test)
> +{
> +       bool was_set;
> +
> +       KUNIT_ASSERT_NOT_ERR_OR_NULL(test, of_root);
> +
> +       was_set = of_node_check_flag(of_root, OF_EMPTY_ROOT);
> +       of_node_set_flag(of_root, OF_EMPTY_ROOT);
> +       KUNIT_EXPECT_FALSE(test, of_have_populated_dt());
> +
> +       if (was_set)
> +               of_node_set_flag(of_root, OF_EMPTY_ROOT);
> +}
> +
> +static struct kunit_case of_have_populated_dt_test_cases[] = {
> +       KUNIT_CASE(of_have_populated_dt_false_when_flag_set),
> +       KUNIT_CASE(of_have_populated_dt_true_when_flag_clear),
> +       {}
> +};
> +
> +/*
> + * Test suite to confirm behavior of of_have_populated_dt().
> + */
> +static struct kunit_suite of_have_populated_dt_suite = {
> +       .name = "of_have_populated_dt",
> +       .test_cases = of_have_populated_dt_test_cases,
> +};
> +
> +kunit_test_suites(
> +       &dtb_suite,
> +       &of_have_populated_dt_suite,
> +);
> +MODULE_LICENSE("GPL");
> --
> https://git.kernel.org/pub/scm/linux/kernel/git/clk/linux.git/
> https://git.kernel.org/pub/scm/linux/kernel/git/sboyd/spmi.git
>
Stephen Boyd Jan. 22, 2024, 10:48 p.m. UTC | #2
Quoting David Gow (2024-01-15 21:03:12)
> On Sat, 13 Jan 2024 at 04:07, Stephen Boyd <sboyd@kernel.org> wrote:
> >
> > Add a KUnit test that confirms a DTB has been loaded, i.e. there is a
> > root node, and that the of_have_populated_dt() API works properly.
> >
> > Cc: Rob Herring <robh+dt@kernel.org>
> > Cc: Frank Rowand <frowand.list@gmail.com>
> > Cc: David Gow <davidgow@google.com>
> > Cc: Brendan Higgins <brendan.higgins@linux.dev>
> > Signed-off-by: Stephen Boyd <sboyd@kernel.org>
> > ---
> 
> I won't pretend to be a devicetree expert, but this looks good to me
> from a KUnit point of view, and passes comfortably here.
> 
> checkpatch seems to have one complaint about the kconfig help text.
> Personally, I think the brief description is fine.
> 
> Reviewed-by: David Gow <davidgow@google.com>
> 

Thanks! I noticed that x86 has some devicetree init code. Did you happen
to try on an x86 kvm instance? Or only run on UML?

----8<----
diff --git a/arch/x86/kernel/devicetree.c b/arch/x86/kernel/devicetree.c
index afd09924094e..650752d112a6 100644
--- a/arch/x86/kernel/devicetree.c
+++ b/arch/x86/kernel/devicetree.c
@@ -283,22 +283,24 @@ void __init x86_flattree_get_config(void)
 	u32 size, map_len;
 	void *dt;
 
-	if (!initial_dtb)
-		return;
+	if (initial_dtb) {
+		map_len = max(PAGE_SIZE - (initial_dtb & ~PAGE_MASK), (u64)128);
 
-	map_len = max(PAGE_SIZE - (initial_dtb & ~PAGE_MASK), (u64)128);
+		dt = early_memremap(initial_dtb, map_len);
+		size = fdt_totalsize(dt);
+		if (map_len < size) {
+			early_memunmap(dt, map_len);
+			dt = early_memremap(initial_dtb, size);
+			map_len = size;
+		}
 
-	dt = early_memremap(initial_dtb, map_len);
-	size = fdt_totalsize(dt);
-	if (map_len < size) {
-		early_memunmap(dt, map_len);
-		dt = early_memremap(initial_dtb, size);
-		map_len = size;
+		early_init_dt_verify(dt);
 	}
 
-	early_init_dt_verify(dt);
 	unflatten_and_copy_device_tree();
-	early_memunmap(dt, map_len);
+
+	if (initial_dtb)
+		early_memunmap(dt, map_len);
 }
 #endif
David Gow Jan. 24, 2024, 7:25 a.m. UTC | #3
On Tue, 23 Jan 2024 at 06:48, Stephen Boyd <sboyd@kernel.org> wrote:
>
> Quoting David Gow (2024-01-15 21:03:12)
> > On Sat, 13 Jan 2024 at 04:07, Stephen Boyd <sboyd@kernel.org> wrote:
> > >
> > > Add a KUnit test that confirms a DTB has been loaded, i.e. there is a
> > > root node, and that the of_have_populated_dt() API works properly.
> > >
> > > Cc: Rob Herring <robh+dt@kernel.org>
> > > Cc: Frank Rowand <frowand.list@gmail.com>
> > > Cc: David Gow <davidgow@google.com>
> > > Cc: Brendan Higgins <brendan.higgins@linux.dev>
> > > Signed-off-by: Stephen Boyd <sboyd@kernel.org>
> > > ---
> >
> > I won't pretend to be a devicetree expert, but this looks good to me
> > from a KUnit point of view, and passes comfortably here.
> >
> > checkpatch seems to have one complaint about the kconfig help text.
> > Personally, I think the brief description is fine.
> >
> > Reviewed-by: David Gow <davidgow@google.com>
> >
>
> Thanks! I noticed that x86 has some devicetree init code. Did you happen
> to try on an x86 kvm instance? Or only run on UML?
>

I admit, I only tested on UML, plus a quick check that the default
kunitconfig wasn't broken on anything else.

A further look is showing:
aarch64: PASSED
UML: PASSED
UML LLVM: PASSED
powerpc64: PASSED
m68k: FAILED
i386: FAILED
x86_64: FAILED
x86_64 KASAN: FAILED

The failures are all of the form:
> [15:18:34] ============ of_have_populated_dt (2 subtests) =============
> [15:18:34] # of_have_populated_dt_false_when_flag_set: ASSERTION FAILED at drivers/of/of_test.c:53
> [15:18:34] Expected of_root is not null, but is
> [15:18:34] [FAILED] of_have_populated_dt_false_when_flag_set
> [15:18:34] # of_have_populated_dt_true_when_flag_clear: ASSERTION FAILED at drivers/of/of_test.c:70
> [15:18:34] Expected of_root is not null, but is
> [15:18:34] [FAILED] of_have_populated_dt_true_when_flag_clear
> [15:18:34]     # module: of_test
> [15:18:34] # of_have_populated_dt: pass:0 fail:2 skip:0 total:2
> [15:18:34] # Totals: pass:0 fail:2 skip:0 total:2
> [15:18:34] ============== [FAILED] of_have_populated_dt ===============

-- David

> ----8<----
> diff --git a/arch/x86/kernel/devicetree.c b/arch/x86/kernel/devicetree.c
> index afd09924094e..650752d112a6 100644
> --- a/arch/x86/kernel/devicetree.c
> +++ b/arch/x86/kernel/devicetree.c
> @@ -283,22 +283,24 @@ void __init x86_flattree_get_config(void)
>         u32 size, map_len;
>         void *dt;
>
> -       if (!initial_dtb)
> -               return;
> +       if (initial_dtb) {
> +               map_len = max(PAGE_SIZE - (initial_dtb & ~PAGE_MASK), (u64)128);
>
> -       map_len = max(PAGE_SIZE - (initial_dtb & ~PAGE_MASK), (u64)128);
> +               dt = early_memremap(initial_dtb, map_len);
> +               size = fdt_totalsize(dt);
> +               if (map_len < size) {
> +                       early_memunmap(dt, map_len);
> +                       dt = early_memremap(initial_dtb, size);
> +                       map_len = size;
> +               }
>
> -       dt = early_memremap(initial_dtb, map_len);
> -       size = fdt_totalsize(dt);
> -       if (map_len < size) {
> -               early_memunmap(dt, map_len);
> -               dt = early_memremap(initial_dtb, size);
> -               map_len = size;
> +               early_init_dt_verify(dt);
>         }
>
> -       early_init_dt_verify(dt);
>         unflatten_and_copy_device_tree();
> -       early_memunmap(dt, map_len);
> +
> +       if (initial_dtb)
> +               early_memunmap(dt, map_len);
>  }
>  #endif
diff mbox series

Patch

diff --git a/drivers/of/.kunitconfig b/drivers/of/.kunitconfig
new file mode 100644
index 000000000000..5a8fee11978c
--- /dev/null
+++ b/drivers/of/.kunitconfig
@@ -0,0 +1,3 @@ 
+CONFIG_KUNIT=y
+CONFIG_OF=y
+CONFIG_OF_KUNIT_TEST=y
diff --git a/drivers/of/Kconfig b/drivers/of/Kconfig
index 9628e48baa15..a527ba8451d9 100644
--- a/drivers/of/Kconfig
+++ b/drivers/of/Kconfig
@@ -37,6 +37,15 @@  config OF_UNITTEST
 
 	  If unsure, say N here. This option is not safe to enable.
 
+config OF_KUNIT_TEST
+	tristate "Devicetree KUnit DTB Test" if !KUNIT_ALL_TESTS
+	depends on KUNIT
+	default KUNIT_ALL_TESTS
+	help
+	  This option builds KUnit unit tests for device tree infrastructure.
+
+	  If unsure, say N here, but this option is safe to enable.
+
 config OF_ALL_DTBS
 	bool "Build all Device Tree Blobs"
 	depends on COMPILE_TEST
diff --git a/drivers/of/Makefile b/drivers/of/Makefile
index df305348d1cb..251d33532148 100644
--- a/drivers/of/Makefile
+++ b/drivers/of/Makefile
@@ -19,4 +19,6 @@  obj-y	+= kexec.o
 endif
 endif
 
+obj-$(CONFIG_OF_KUNIT_TEST) += of_test.o
+
 obj-$(CONFIG_OF_UNITTEST) += unittest-data/
diff --git a/drivers/of/of_test.c b/drivers/of/of_test.c
new file mode 100644
index 000000000000..7609ad3081b9
--- /dev/null
+++ b/drivers/of/of_test.c
@@ -0,0 +1,98 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * KUnit tests for OF APIs
+ */
+#include <linux/module.h>
+#include <linux/of.h>
+
+#include <kunit/test.h>
+
+/*
+ * Test that the root node "/" exists.
+ */
+static void dtb_root_node_found_by_path(struct kunit *test)
+{
+	struct device_node *np;
+
+	np = of_find_node_by_path("/");
+	KUNIT_EXPECT_NOT_ERR_OR_NULL(test, np);
+	of_node_put(np);
+}
+
+/*
+ * Test that the of_root global variable is always populated when DT
+ * code is enabled.
+ */
+static void dtb_root_node_populates_of_root(struct kunit *test)
+{
+	KUNIT_EXPECT_NOT_ERR_OR_NULL(test, of_root);
+}
+
+static struct kunit_case dtb_test_cases[] = {
+	KUNIT_CASE(dtb_root_node_found_by_path),
+	KUNIT_CASE(dtb_root_node_populates_of_root),
+	{}
+};
+
+/*
+ * Test suite to confirm a live DTB is loaded.
+ */
+static struct kunit_suite dtb_suite = {
+	.name = "dtb",
+	.test_cases = dtb_test_cases,
+};
+
+/*
+ * Test that calling of_have_populated_dt() returns false when
+ * the OF_EMPTY_ROOT flag isn't set.
+ */
+static void of_have_populated_dt_false_when_flag_set(struct kunit *test)
+{
+	bool was_set;
+
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, of_root);
+
+	was_set = of_node_test_and_set_flag(of_root, OF_EMPTY_ROOT);
+	KUNIT_EXPECT_FALSE(test, of_have_populated_dt());
+
+	if (!was_set)
+		of_node_clear_flag(of_root, OF_EMPTY_ROOT);
+}
+
+/*
+ * Test that calling of_have_populated_dt() returns false when
+ * the OF_EMPTY_ROOT flag isn't set.
+ */
+static void of_have_populated_dt_true_when_flag_clear(struct kunit *test)
+{
+	bool was_set;
+
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, of_root);
+
+	was_set = of_node_check_flag(of_root, OF_EMPTY_ROOT);
+	of_node_set_flag(of_root, OF_EMPTY_ROOT);
+	KUNIT_EXPECT_FALSE(test, of_have_populated_dt());
+
+	if (was_set)
+		of_node_set_flag(of_root, OF_EMPTY_ROOT);
+}
+
+static struct kunit_case of_have_populated_dt_test_cases[] = {
+	KUNIT_CASE(of_have_populated_dt_false_when_flag_set),
+	KUNIT_CASE(of_have_populated_dt_true_when_flag_clear),
+	{}
+};
+
+/*
+ * Test suite to confirm behavior of of_have_populated_dt().
+ */
+static struct kunit_suite of_have_populated_dt_suite = {
+	.name = "of_have_populated_dt",
+	.test_cases = of_have_populated_dt_test_cases,
+};
+
+kunit_test_suites(
+	&dtb_suite,
+	&of_have_populated_dt_suite,
+);
+MODULE_LICENSE("GPL");