[PATCH v2 1/2] drm/msm/gen_header: allow skipping the validation

[Dmitry Baryshkov]

We don't need to run the validation of the XML files if we are just
compiling the kernel. Skip the validation unless the user enables
corresponding Kconfig option. This removes a warning from gen_header.py
about lxml being not installed.

Reported-by: Stephen Rothwell <sfr at canb.auug.org.au>
Closes: https://lore.kernel.org/all/20240409120108.2303d0bd@canb.auug.org.au/
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov at linaro.org>
---
 drivers/gpu/drm/msm/Kconfig                 |  8 ++++++++
 drivers/gpu/drm/msm/Makefile                |  9 ++++++++-
 drivers/gpu/drm/msm/registers/gen_header.py | 14 +++++++++++---
 3 files changed, 27 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/msm/Kconfig b/drivers/gpu/drm/msm/Kconfig
index f202f26adab2..4c9bf237d4a2 100644
--- a/drivers/gpu/drm/msm/Kconfig
+++ b/drivers/gpu/drm/msm/Kconfig
@@ -54,6 +54,14 @@ config DRM_MSM_GPU_SUDO
 	  Only use this if you are a driver developer.  This should *not*
 	  be enabled for production kernels.  If unsure, say N.
 
+config DRM_MSM_VALIDATE_XML
+	bool "Validate XML register files against schema"
+	depends on DRM_MSM && EXPERT
+	depends on $(success,$(PYTHON3) -c "import lxml")
+	help
+	  Validate XML files with register definitions against rules-fd schema.
+	  This option is mostly targeting DRM MSM developers. If unsure, say N.
+
 config DRM_MSM_MDSS
 	bool
 	depends on DRM_MSM
diff --git a/drivers/gpu/drm/msm/Makefile b/drivers/gpu/drm/msm/Makefile
index c861de58286c..718968717ad5 100644
--- a/drivers/gpu/drm/msm/Makefile
+++ b/drivers/gpu/drm/msm/Makefile
@@ -156,8 +156,15 @@ msm-y += $(adreno-y) $(msm-display-y)
 
 obj-$(CONFIG_DRM_MSM)	+= msm.o
 
+ifeq (y,$(CONFIG_DRM_MSM_VALIDATE_XML))
+	headergen-opts += --validate
+else
+	headergen-opts += --no-validate
+endif
+
 quiet_cmd_headergen = GENHDR  $@
-      cmd_headergen = mkdir -p $(obj)/generated && $(PYTHON3) $(srctree)/$(src)/registers/gen_header.py --rnn $(srctree)/$(src)/registers --xml $< c-defines > $@
+      cmd_headergen = mkdir -p $(obj)/generated && $(PYTHON3) $(srctree)/$(src)/registers/gen_header.py \
+		      $(headergen-opts) --rnn $(srctree)/$(src)/registers --xml $< c-defines > $@
 
 $(obj)/generated/%.xml.h: $(src)/registers/adreno/%.xml \
 		$(src)/registers/adreno/adreno_common.xml \
diff --git a/drivers/gpu/drm/msm/registers/gen_header.py b/drivers/gpu/drm/msm/registers/gen_header.py
index 90d5c2991d05..fc3bfdc991d2 100644
--- a/drivers/gpu/drm/msm/registers/gen_header.py
+++ b/drivers/gpu/drm/msm/registers/gen_header.py
@@ -538,6 +538,9 @@ class Parser(object):
 		self.variants.add(reg.domain)
 
 	def do_validate(self, schemafile):
+		if self.validate == False:
+			return
+
 		try:
 			from lxml import etree
 
@@ -567,7 +570,10 @@ class Parser(object):
 			if not xmlschema.validate(xml_doc):
 				error_str = str(xmlschema.error_log.filter_from_errors()[0])
 				raise self.error("Schema validation failed for: " + filename + "\n" + error_str)
-		except ImportError:
+		except ImportError as e:
+			if self.validate:
+				raise e
+
 			print("lxml not found, skipping validation", file=sys.stderr)
 
 	def do_parse(self, filename):
@@ -586,9 +592,10 @@ class Parser(object):
 		self.stack.pop()
 		file.close()
 
-	def parse(self, rnn_path, filename):
+	def parse(self, rnn_path, filename, validate):
 		self.path = rnn_path
 		self.stack = []
+		self.validate = validate
 		self.do_parse(filename)
 
 	def parse_reg(self, attrs, bit_size):
@@ -853,7 +860,7 @@ def dump_c(args, guard, func):
 	p = Parser()
 
 	try:
-		p.parse(args.rnn, args.xml)
+		p.parse(args.rnn, args.xml, args.validate)
 	except Error as e:
 		print(e, file=sys.stderr)
 		exit(1)
@@ -941,6 +948,7 @@ def main():
 	parser = argparse.ArgumentParser()
 	parser.add_argument('--rnn', type=str, required=True)
 	parser.add_argument('--xml', type=str, required=True)
+	parser.add_argument('--validate', action=argparse.BooleanOptionalAction)
 
 	subparsers = parser.add_subparsers()
 	subparsers.required = True

-- 
2.39.2