arch: add option to disable internal toolchain backend

Some architectures or specific cores do not have support in upstream
gcc. Currently, they are individually listed as exclusions in the
toolchain choice.

This poses a maintainance burden, as the knowledge about what gcc
version supports what architecture is split across many places: the
toolchain choice, the gcc version choice, the external toolchains.

As a first step, add a blind option that architectures or individual
cores may select to indicate they lack support in our internal backend.

Actual use of the option will come in followup patches.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Arnout Vandecappelle <arnout@mind.be>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

diff --git a/arch/Config.in b/arch/Config.in
index f385745e47a0136e02d35d935f2ca699e908c654..caf5a318ab5af0679d46941f6d2cac6ab3851999 100644 (file)
--- a/arch/Config.in
+++ b/arch/Config.in
@@ -250,6 +250,16 @@ config BR2_xtensa
 
 endchoice
 
+# For some architectures or specific cores, our internal toolchain
+# backend is not suitable (like, missing support in upstream gcc, or
+# no ChipCo fork exists...)
+config BR2_ARCH_HAS_NO_TOOLCHAIN_BUILDROOT
+       bool
+
+config BR2_ARCH_HAS_TOOLCHAIN_BUILDROOT
+       bool
+       default y if !BR2_ARCH_HAS_NO_TOOLCHAIN_BUILDROOT
+
 # The following string values are defined by the individual
 # Config.in.$ARCH files
 config BR2_ARCH

diff --git a/toolchain/Config.in b/toolchain/Config.in
index 584d053058bfaeb92831d200ff29755f40bd7070..8866b7da75f8bd2cdedffa126fcca526ef6a3fb1 100644 (file)
--- a/toolchain/Config.in
+++ b/toolchain/Config.in
@@ -43,6 +43,7 @@ choice
 config BR2_TOOLCHAIN_BUILDROOT
        bool "Buildroot toolchain"
        select BR2_TOOLCHAIN_HAS_SHADOW_PASSWORDS
+       depends on BR2_ARCH_HAS_TOOLCHAIN_BUILDROOT
        depends on !BR2_bf606
        depends on !BR2_bf607
        depends on !BR2_bf608