Documentation/coding_style: Issues not mentioned and cleanup patches

This patch adds a bit of a "preamble" to the coding style to provide
guideance on how it should be applied and how style questions that
aren't mentioned should be handled.

Signed-off-by: Julius Werner <jwerner@chromium.org>
Change-Id: I88efd5f1006bd1fd82cea14ea65422d9958dc197
Reviewed-on: https://review.coreboot.org/c/coreboot/+/50966
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Nico Huber <nico.h@gmx.de>

1 files changed, 20 insertions, 6 deletions

diff --git a/Documentation/contributing/coding_style.md b/Documentation/contributing/coding_style.md
index f6a0f540b8..a8c7356bfe 100644
--- a/Documentation/contributing/coding_style.md
+++ b/Documentation/contributing/coding_style.md
@@ -5,12 +5,26 @@ coreboot project. It is in many ways exactly the same as the Linux
 kernel coding style. In fact, most of this document has been copied from
 the [Linux kernel coding style](http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/plain/Documentation/CodingStyle?id=HEAD)
 
-Please at least consider the points made here.
-
-First off, I'd suggest printing out a copy of the GNU coding standards,
-and NOT read it. Burn them, it's a great symbolic gesture.
-
-Anyway, here goes:
+The guidelines in this file should be seen as a strong suggestion, and
+should overrule personal preference. But they may be ignored in
+individual instances when there are good practical reasons to do so, and
+reviewers are in agreement.
+
+Any style questions that are not mentioned in here should be decided
+between the author and reviewers on a case-by-case basis. When modifying
+existing files, authors should try to match the prevalent style in that
+file -- otherwise, they should try to match similar existing files in
+coreboot.
+
+Bulk style changes to existing code ("cleanup patches") should avoid
+changing existing style choices unless they actually violate this style
+guide, or there is broad consensus that the new version is an
+improvement. By default the style choices of the original author should
+be honored. (Note that `checkpatch.pl` is not part of this style guide,
+and neither is `clang-format`. These tools can be useful to find
+potential issues or simplify formatting in new submissions, but they
+were not designed to directly match this guide and may have false
+positives. They should not be bulk-applied to change existing code.)
 
 ## Indentation