diff mbox series

[RFC,2/2] kselftest: Add Devicetree unprobed devices test

Message ID 20230810202413.1780286-3-nfraprado@collabora.com (mailing list archive)
State New
Headers show
Series Add a test to catch unprobed Devicetree devices | expand

Commit Message

Nícolas F. R. A. Prado Aug. 10, 2023, 8:23 p.m. UTC
Introduce a new kselftest to detect devices that were declared in the
Devicetree, and are expected to be probed by a driver, but weren't.

The test uses two lists: a list of compatibles that can match a
Devicetree device to a driver, and a list of compatibles that should be
ignored. The first is automatically generated from a script that parses
the kernel source using Coccinelle, and will be run as part of building
this test, therefore Coccinelle is a build-time dependency for this
test. The list of compatibles to ignore is a hand-crafted list to
capture the few exceptions of compatibles that are expected to match a
driver but not be bound to it.

Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
---

 tools/testing/selftests/Makefile              |  1 +
 tools/testing/selftests/dt/.gitignore         |  1 +
 tools/testing/selftests/dt/Makefile           | 17 ++++++
 .../selftests/dt/compatible_ignore_list       |  3 +
 .../selftests/dt/test_unprobed_devices.sh     | 58 +++++++++++++++++++
 5 files changed, 80 insertions(+)
 create mode 100644 tools/testing/selftests/dt/.gitignore
 create mode 100644 tools/testing/selftests/dt/Makefile
 create mode 100644 tools/testing/selftests/dt/compatible_ignore_list
 create mode 100755 tools/testing/selftests/dt/test_unprobed_devices.sh

Comments

Mark Brown Aug. 11, 2023, 1:54 p.m. UTC | #1
On Thu, Aug 10, 2023 at 04:23:51PM -0400, Nícolas F. R. A. Prado wrote:
> Introduce a new kselftest to detect devices that were declared in the
> Devicetree, and are expected to be probed by a driver, but weren't.
> 
> The test uses two lists: a list of compatibles that can match a
> Devicetree device to a driver, and a list of compatibles that should be
> ignored. The first is automatically generated from a script that parses
> the kernel source using Coccinelle, and will be run as part of building
> this test, therefore Coccinelle is a build-time dependency for this
> test. The list of compatibles to ignore is a hand-crafted list to
> capture the few exceptions of compatibles that are expected to match a
> driver but not be bound to it.

This doesn't appear to produce KTAP output which is going to make it
less useful for generic kselftest runners.
Nícolas F. R. A. Prado Aug. 11, 2023, 2:16 p.m. UTC | #2
On Fri, Aug 11, 2023 at 02:54:56PM +0100, Mark Brown wrote:
> On Thu, Aug 10, 2023 at 04:23:51PM -0400, Nícolas F. R. A. Prado wrote:
> > Introduce a new kselftest to detect devices that were declared in the
> > Devicetree, and are expected to be probed by a driver, but weren't.
> > 
> > The test uses two lists: a list of compatibles that can match a
> > Devicetree device to a driver, and a list of compatibles that should be
> > ignored. The first is automatically generated from a script that parses
> > the kernel source using Coccinelle, and will be run as part of building
> > this test, therefore Coccinelle is a build-time dependency for this
> > test. The list of compatibles to ignore is a hand-crafted list to
> > capture the few exceptions of compatibles that are expected to match a
> > driver but not be bound to it.
> 
> This doesn't appear to produce KTAP output which is going to make it
> less useful for generic kselftest runners.

Right, I'm going to need to rewrite it in C for that, but since I already had
the shell script done, I decided to send it as is for the RFC, since I wanted to
get feedback on the general approach more than anything.

Thanks,
Nícolas
Mark Brown Aug. 17, 2023, 12:26 p.m. UTC | #3
On Fri, Aug 11, 2023 at 10:16:52AM -0400, Nícolas F. R. A. Prado wrote:
> On Fri, Aug 11, 2023 at 02:54:56PM +0100, Mark Brown wrote:

> > This doesn't appear to produce KTAP output which is going to make it
> > less useful for generic kselftest runners.

> Right, I'm going to need to rewrite it in C for that, but since I already had
> the shell script done, I decided to send it as is for the RFC, since I wanted to
> get feedback on the general approach more than anything.

I'm not clear why KTAP would require C?
Nícolas F. R. A. Prado Aug. 17, 2023, 4:17 p.m. UTC | #4
On Thu, Aug 17, 2023 at 01:26:05PM +0100, Mark Brown wrote:
> On Fri, Aug 11, 2023 at 10:16:52AM -0400, Nícolas F. R. A. Prado wrote:
> > On Fri, Aug 11, 2023 at 02:54:56PM +0100, Mark Brown wrote:
> 
> > > This doesn't appear to produce KTAP output which is going to make it
> > > less useful for generic kselftest runners.
> 
> > Right, I'm going to need to rewrite it in C for that, but since I already had
> > the shell script done, I decided to send it as is for the RFC, since I wanted to
> > get feedback on the general approach more than anything.
> 
> I'm not clear why KTAP would require C?

When going through the documentation there was only mention of the C headers for
the kselftest framework which outputs using the KTAP format, so I thought that
was the only acceptable option.

But in the meantime while looking through the other tests I saw you've recently
added ktap output to ftrace/ftracetest. The newly added test in
net/mptcp/mptcp_lib.sh also has its own helpers for outputting in KTAP. There
are also a couple other cases of this in python.

So I can definitely do the same for this test.

Thanks,
Nícolas
Mark Brown Aug. 17, 2023, 5:39 p.m. UTC | #5
On Thu, Aug 17, 2023 at 12:17:38PM -0400, Nícolas F. R. A. Prado wrote:
> On Thu, Aug 17, 2023 at 01:26:05PM +0100, Mark Brown wrote:

> > I'm not clear why KTAP would require C?

> When going through the documentation there was only mention of the C headers for
> the kselftest framework which outputs using the KTAP format, so I thought that
> was the only acceptable option.

> But in the meantime while looking through the other tests I saw you've recently
> added ktap output to ftrace/ftracetest. The newly added test in
> net/mptcp/mptcp_lib.sh also has its own helpers for outputting in KTAP. There
> are also a couple other cases of this in python.

> So I can definitely do the same for this test.

Right, KTAP is a format specification for what appears on stdout - how
that output is generated is immaterial.  It's just that most tests are
written in C so that's where the helpers are.
diff mbox series

Patch

diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile
index 8dca8acdb671..2fe992ca9294 100644
--- a/tools/testing/selftests/Makefile
+++ b/tools/testing/selftests/Makefile
@@ -16,6 +16,7 @@  TARGETS += drivers/dma-buf
 TARGETS += drivers/s390x/uvdevice
 TARGETS += drivers/net/bonding
 TARGETS += drivers/net/team
+TARGETS += dt
 TARGETS += efivarfs
 TARGETS += exec
 TARGETS += fchmodat2
diff --git a/tools/testing/selftests/dt/.gitignore b/tools/testing/selftests/dt/.gitignore
new file mode 100644
index 000000000000..f6476c9f2884
--- /dev/null
+++ b/tools/testing/selftests/dt/.gitignore
@@ -0,0 +1 @@ 
+compatible_list
diff --git a/tools/testing/selftests/dt/Makefile b/tools/testing/selftests/dt/Makefile
new file mode 100644
index 000000000000..fa5f3c12a659
--- /dev/null
+++ b/tools/testing/selftests/dt/Makefile
@@ -0,0 +1,17 @@ 
+COCCI = $(shell which spatch 2>/dev/null)
+
+ifneq ($(COCCI),)
+TEST_PROGS := test_unprobed_devices.sh
+TEST_GEN_FILES := compatible_list
+TEST_FILES := compatible_ignore_list
+
+include ../lib.mk
+
+$(OUTPUT)/compatible_list:
+	cd $(top_srcdir) && ./scripts/dtc/extract-matchable-dt-compatibles > $(OUTPUT)/compatible_list
+
+else
+
+all:
+
+endif
diff --git a/tools/testing/selftests/dt/compatible_ignore_list b/tools/testing/selftests/dt/compatible_ignore_list
new file mode 100644
index 000000000000..5d7fc6229428
--- /dev/null
+++ b/tools/testing/selftests/dt/compatible_ignore_list
@@ -0,0 +1,3 @@ 
+fixed-factor-clock
+fixed-clock
+simple-mfd
diff --git a/tools/testing/selftests/dt/test_unprobed_devices.sh b/tools/testing/selftests/dt/test_unprobed_devices.sh
new file mode 100755
index 000000000000..4741bedefd1f
--- /dev/null
+++ b/tools/testing/selftests/dt/test_unprobed_devices.sh
@@ -0,0 +1,58 @@ 
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+#
+# Copyright (c) 2023 Collabora Ltd
+#
+# Based on Frank Rowand's dt_stat script.
+#
+# This script tests for devices that were declared on the Devicetree and are
+# expected to bind to a driver, but didn't.
+#
+# To achieve this, two lists are used:
+# * a list of the compatibles that can be matched by a Devicetree node
+# * a list of compatibles that should be ignored
+#
+PDT=/proc/device-tree/
+COMPAT_LIST=compatible_list
+IGNORE_LIST=compatible_ignore_list
+
+nodes_compatible=$(
+	for node_compat in $(find ${PDT} -name compatible); do
+		node=$(dirname "${node_compat}")
+		# Check if node is available
+		[[ -e "${node}"/status && $(tr -d '\000' < "${node}"/status) != "okay" ]] && continue
+		echo "${node}" | sed -e 's|\/proc\/device-tree||'
+	done | sort
+	)
+
+nodes_dev_bound=$(
+	IFS=$'\n'
+	for uevent in $(find /sys/devices -name uevent); do
+		if [[ -d "$(dirname "${uevent}")"/driver ]]; then
+			grep '^OF_FULLNAME=' "${uevent}" | sed -e 's|OF_FULLNAME=||'
+		fi
+	done
+	)
+
+retval=0
+for node in ${nodes_compatible}; do
+	if ! echo "${nodes_dev_bound}" | grep -E -q "(^| )${node}( |\$)"; then
+		compatibles=$(tr '\000' '\n' < "${PDT}"/"${node}"/compatible)
+
+		for compatible in ${compatibles}; do
+			if grep -x -q "${compatible}" "$IGNORE_LIST"; then
+				echo "DEBUG: Ignoring " "${node}"
+				continue
+			fi
+
+			if grep -x -q "${compatible}" "$COMPAT_LIST"; then
+				echo "BROKEN: " "${node}"
+				retval=1
+				continue 2
+			fi
+		done
+		echo "DEBUG: Skipping " "${node}"
+	fi
+done
+
+exit $retval