xbmk: make all projects multi-tree

we currently distinguish, by virtue of logic, multi-
and single-tree projects. this introduces a lot of
complexity, so the following patch has removed this
distinction. all single-tree projects are now multi
tree, but with only one tree.

other design changes:

config/git removed. rev/tree now handled with mkhelper
and target configs. this allows per-tree remote handling,
so we could (for example) add the mrchromebox coreboot
fork easily, for specific chromebook models.

config/project is now config/module/project. this
cleans up the main config/ directory.

cfgname variable: .config no longer hardcoded when
doing configs in projects. it is configurable with
this variable. if unset, the previous .cfg is used

noconfig variable: set this in target/mkhelper
configs, and config/module/project/tree/config/ is
unused; instead, make is called without config copying.
a "noconfig" placeholder is used. this enables cleaner
usage of previously single-tree projects in the new
multi-tree-only structure.

cfgvars: variables reinitialised in project config are
cleaned more reliably. in particular, several variables
e.g. autogenargs were not being reset between projects,
although the autogenargs variable is currently unused.

general cleanup has been conducted across the build
system, as part of this redesign. several parts of the
build system more over-engineered as a result of the
previous design, and the new design enabled a severe
reduction in sloccount (75 lines reduced in lbmk).

yes, this change *adds features* but there are fewer
lines of code than before. this is the best kind of
change. way better than the 3-line-diff. yes.

rev= and tree= are set more centrally in configs. the
mkhelper config can be used to set url/url_bkup, but
individual trees can override them.

configs have been cleaned up, with several variables
now much more heavily centralised. config/git/ was
used before to first download the bare repository, and
then the real clone was made with patches. this allows
git repositories to be cached for future re-builds.

with config/git/ gone, the download logic for projects
is more centrally implemented. a separate call to ./mk -f
is no longer performed, and in fact ./mk -f never needs
to be used anymore as a result. ./mk -f now is basically
the same thing as -b, just without any action performed.

this change will allow rapid expansion of the libreboot
project. i want to add hundreds of chromebooks to the
project, using mrchromebox, but the previous design did
not permit this. this change means that i can easily have
unlimited upstreams per project. coreboot will, in some
follow-up changes, have the following upstreams:

coreboot/default: coreboot.org
coreboot/fam15h: 15h.org fork
coreboot/chromebook: mrchromebox fork

this can now be done freely without massive changes to
the build system. under the previous design, i worked on
a now-abandoned patch to do N remotes per project, reading
repo links from a file. this meant that i'd have coreboot.org
first (main and backup), then mrchromebox. this meant that
lbmk would failover through to mrchromebox, wasting time
for the user.

this new design is much cleaner, and will enable the
project to be maintained much more easily.

Signed-off-by: Leah Rowe <leah@libreboot.org>

1 files changed, 61 insertions, 0 deletions

diff --git a/config/module/coreboot/default/patches/0029-src-intel-skylake-Disable-stack-overflow-debug-optio.patch b/config/module/coreboot/default/patches/0029-src-intel-skylake-Disable-stack-overflow-debug-optio.patch
new file mode 100644
index 00000000..78ccf785
--- /dev/null
+++ b/config/module/coreboot/default/patches/0029-src-intel-skylake-Disable-stack-overflow-debug-optio.patch
@@ -0,0 +1,61 @@
+From 95a0af0eea56e1bddcb243ed135835448b90fa56 Mon Sep 17 00:00:00 2001
+From: Leah Rowe <leah@libreboot.org>
+Date: Mon, 6 Jan 2025 01:36:23 +0000
+Subject: [PATCH 29/48] src/intel/skylake: Disable stack overflow debug options
+
+The option was appearing in T480/3050micro configs of lbmk,
+after updating on the coreboot/next uprev for 20241206 rev8:
+
+CONFIG_DEBUG_STACK_OVERFLOW_BREAKPOINTS=y
+
+I did some digging. See coreboot commit:
+
+commit 51cc2bacb6b07279b97e9934d079060475481fb6
+Author: Subrata Banik <subratabanik@google.com>
+Date:   Fri Dec 13 13:07:28 2024 +0530
+
+    soc/intel/pantherlake: Disable stack overflow debug options
+
+Well now:
+
+I'm disabling this behaviour on Skylake, for the same
+behaviour, because I want as few behaviour changes in general,
+as possible, for the rev8 release.
+
+According to Subrata's patch, which was for Pantherlake,
+without this change, stack corruption can occur on verstage
+and romstage early on. Please look at that coreboot patch,
+referenced above, for clarity.
+
+I see no harm in disabling this option for Skylake, since
+the behaviour that it otherwise enables was not present
+before.
+
+Signed-off-by: Leah Rowe <leah@libreboot.org>
+---
+ src/soc/intel/skylake/Kconfig | 9 +++++++++
+ 1 file changed, 9 insertions(+)
+
+diff --git a/src/soc/intel/skylake/Kconfig b/src/soc/intel/skylake/Kconfig
+index 7c530f2c75..70c2a7643c 100644
+--- a/src/soc/intel/skylake/Kconfig
++++ b/src/soc/intel/skylake/Kconfig
+@@ -131,6 +131,15 @@ config DCACHE_RAM_SIZE
+ 	  The size of the cache-as-ram region required during bootblock
+ 	  and/or romstage.
+ 
++# Override DEBUG Kconfig to avoid false alarm about stack overflow.
++config DEBUG_STACK_OVERFLOW_BREAKPOINTS
++	bool
++	default n
++
++config DEBUG_STACK_OVERFLOW_BREAKPOINTS_IN_ALL_STAGES
++	bool
++	default n
++
+ config DCACHE_BSP_STACK_SIZE
+ 	hex
+ 	default 0x20400 if FSP_USES_CB_STACK
+-- 
+2.47.3
+