CircleCI: optimize toolchain sharing across Dasharo boards

Reorganize CircleCI workflow to properly share toolchains:

1. Each toolchain version now has a dedicated first build that creates
   the crossgcc toolchain, which subsequent boards then reuse:
   - librem_14: 24.02.01 toolchain (purism)
   - novacustom-nv4x_adl: 24.12 toolchain (dasharo_nv4x, dasharo_msi_*)
   - novacustom-v560tu: 25.03 toolchain (dasharo_v56)
   - EOL_t480-hotp-maximized: 25.09 toolchain

2. Update cache paths to include all coreboot versions and Dasharo forks:
   - Added: coreboot-4.20.1, coreboot-4.22.01, coreboot-24.12, coreboot-25.03
   - Replaced coreboot-dasharo with version-specific directories:
     coreboot-dasharo_v56, coreboot-dasharo_nv4x,
     coreboot-dasharo_msi_z790, coreboot-dasharo_msi_z690

3. Fixed dependency chain:
   - novacustom-v540tu now depends on novacustom-v560tu (25.03 toolchain)
   - UNTESTED_msi_z790p_ddr4 depends on novacustom-nv4x_adl (24.12 toolchain)
   - All 24.12-based boards now chain from novacustom-nv4x_adl

This reduces build time by avoiding redundant toolchain rebuilds.

Signed-off-by: Thierry Laurion <insurgo@riseup.net>

Author: tlaurion

.circleci/config.yml

@@ -196,13 +196,25 @@ jobs:
           # CircleCI removed their wildcard support, so we have to list precise versions to cache in directory names
           key: nix-docker-heads-coreboot-musl-cross-make-{{ checksum "./tmpDir/coreboot_musl-cross-make.sha256sums" }}{{ .Environment.CACHE_VERSION }}
           paths:
+            # ppc64
             - build/ppc64/coreboot-talos_2
             - build/ppc64/musl-cross-make-fd6be58297ee21fcba89216ccd0d4aca1e3f1c5c
+            # x86
             - build/x86/coreboot-4.11
+            - build/x86/coreboot-4.20.1
+            - build/x86/coreboot-4.22.01
             - build/x86/coreboot-24.02.01
+            - build/x86/coreboot-24.12
+            - build/x86/coreboot-25.03
             - build/x86/coreboot-25.09
-            - build/x86/coreboot-dasharo
+            # Dasharo forks (coreboot git checkouts, not releases)
+            - build/x86/coreboot-dasharo_v56
+            - build/x86/coreboot-dasharo_nv4x
+            - build/x86/coreboot-dasharo_msi_z790
+            - build/x86/coreboot-dasharo_msi_z690
             - build/x86/coreboot-purism
+            - build/x86/coreboot-talos_2
+            # musl-cross-make
             - build/x86/musl-cross-make-fd6be58297ee21fcba89216ccd0d4aca1e3f1c5c
             - crossgcc
             - packages
@@ -239,34 +251,44 @@ workflows:
           requires:
             - prep_env
 
-      # Below, sequentially build one board for each coreboot version.
-      # The last board in the sequence is the dependency for the parallel boards built at the end, and also save_cache.
+      # Below, sequentially build one board for each coreboot version/toolchain.
+      # The first board of each toolchain version builds the crossgcc toolchain.
+      # Subsequent boards using the same toolchain depend on that first board.
 
-      # coreboot 24.02.01
+      # Toolchain: 24.02.01 (used by purism)
+      # coreboot purism: based on coreboot 24.02.01, reuse crossgcc from 24.02.01
+      - build_and_persist:
+          name: librem_14
+          target: librem_14
+          subcommand: ""
+          requires:
+            - x86-musl-cross-make
+
+      # Toolchain: 24.12 (used by dasharo_nv4x, dasharo_msi_z690, dasharo_msi_z790)
       - build_and_persist:
           name: novacustom-nv4x_adl
           target: novacustom-nv4x_adl
           subcommand: ""
           requires:
             - x86-musl-cross-make
 
-      # coreboot purism: based on coreboot 24.02.01, reuse dasharo 24.02.01 crossgcc
+      # Toolchain: 25.03 (used by dasharo_v56)
       - build_and_persist:
-          name: librem_14
-          target: librem_14
+          name: novacustom-v560tu
+          target: novacustom-v560tu
           subcommand: ""
           requires:
-            - novacustom-nv4x_adl
+            - x86-musl-cross-make
 
-      # t480 is based on 25.09 coreboot release, not sharing any buildstack from now, depend on muscl-cross cache
+      # Toolchain: 25.09 (used by t480)
       - build_and_persist:
           name: EOL_t480-hotp-maximized
           target: EOL_t480-hotp-maximized
           subcommand: ""
           requires:
             - x86-musl-cross-make
 
-      # coreboot talos_2
+      # coreboot talos_2 (ppc64)
       - build_and_persist:
           name: UNTESTED_talos-2
           arch: ppc64
@@ -283,22 +305,20 @@ workflows:
           requires:
             - x86-musl-cross-make
 
-      # dasharo_msi
-      - build_and_persist:
-          name: UNTESTED_msi_z690a_ddr4
-          target: UNTESTED_msi_z690a_ddr4
-          subcommand: ""
-          requires:
-            - x86-musl-cross-make
-
       # Cache one workspace per architecture
       # Make sure workspace caches are chainloaded and the last in chain for an arch is saved
       - save_cache:
           requires:
             - UNTESTED_talos-2
             - EOL_t480-hotp-maximized
 
-      # Those onboarding new boards should add their entries below.
+      #======================================================================
+      # Parallel board builds - depend on toolchain providers above
+      #======================================================================
+
+      #----------------------------------------
+      # Toolchain 25.09 (t480 and variants)
+      #----------------------------------------
       # coreboot 25.09 boards
       - build:
           name: EOL_x220-hotp-maximized
@@ -562,47 +582,57 @@ workflows:
           requires:
             - EOL_t480-hotp-maximized
 
-      # dasharo release, share 24.02.01 utils/crossgcc
+      #----------------------------------------
+      # Toolchain 24.12 (dasharo_nv4x, dasharo_msi_z690, dasharo_msi_z790)
+      #----------------------------------------
+      # These boards share the 24.12 toolchain from novacustom-nv4x_adl
+
+      # dasharo_nv4x: NV4x ADL / NS50
       - build:
           name: UNTESTED_nitropad-ns50
           target: UNTESTED_nitropad-ns50
           subcommand: ""
           requires:
             - novacustom-nv4x_adl
 
-      #NovaCustom v56 boards are based on coreboot 24.02.01 fork, so depend on nv4x_adl
+      # dasharo_msi_z690: MSI Z690 boards
       - build:
-          name: novacustom-v560tu
-          target: novacustom-v560tu
-          subcommand: ""
-          requires:
-            - novacustom-nv4x_adl
-
-      - build:
-          name: novacustom-v540tu
-          target: novacustom-v540tu
+          name: UNTESTED_msi_z690a_ddr4
+          target: UNTESTED_msi_z690a_ddr4
           subcommand: ""
           requires:
             - novacustom-nv4x_adl
 
-      # dasharo_msi
       - build:
           name: UNTESTED_msi_z690a_ddr5
           target: UNTESTED_msi_z690a_ddr5
           subcommand: ""
           requires:
             - UNTESTED_msi_z690a_ddr4
 
+      # dasharo_msi_z790: MSI Z790 boards
       - build:
           name: UNTESTED_msi_z790p_ddr4
           target: UNTESTED_msi_z790p_ddr4
           subcommand: ""
           requires:
-            - UNTESTED_msi_z690a_ddr4
+            - novacustom-nv4x_adl
 
       - build:
           name: msi_z790p_ddr5
           target: msi_z790p_ddr5
           subcommand: ""
           requires:
-            - UNTESTED_msi_z690a_ddr4
+            - UNTESTED_msi_z790p_ddr4
+
+      #----------------------------------------
+      # Toolchain 25.03 (dasharo_v56)
+      #----------------------------------------
+      # These boards share the 25.03 toolchain from novacustom-v560tu
+
+      - build:
+          name: novacustom-v540tu
+          target: novacustom-v540tu
+          subcommand: ""
+          requires:
+            - novacustom-v560tu