[Buildroot] [git commit branch/2022.05.x] arch/Config.in.riscv: lp64f ABI is only supported if MMU is enabled

[Peter Korsgaard]

commit: https://git.buildroot.net/buildroot/commit/?id=cf0491ebcdff57f64fd3e25da4528612bc7b7529
branch: https://git.buildroot.net/buildroot/commit/?id=refs/heads/2022.05.x

Even though that seems weird, the LP64F ABI is only supported when MMU
support is enabled. Indeed, as per commit
9a51381cedc16e6d70cb85e1144f6e0fa89af69a ("package/uclibc: prevent
config with unsupported RISC-V float ABI"), uClibc does not support
LP64F. But uClibc is the only C library that support RISC-V 64-bit
noMMU.

So the selection of LP64F and !MMU is impossible. Right now this
selection causes a build failure as no C library is enabled.

This commit fixes this by ensuring we cannot use LP64F when MMU
support is not available.

Fixes:

  http://autobuild.buildroot.net/results/6320dcc655f1871eb8bf6a9689bddde7447385f5/

Signed-off-by: Thomas Petazzoni <thomas.petazzoni at bootlin.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998 at free.fr>
(cherry picked from commit f7d60ee57d7d5155d4b3ac5f5ca12b7445faf95c)
Signed-off-by: Peter Korsgaard <peter at korsgaard.com>
---
 arch/Config.in.riscv | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/Config.in.riscv b/arch/Config.in.riscv
index 288ed833eb..30bdcaa80b 100644
--- a/arch/Config.in.riscv
+++ b/arch/Config.in.riscv
@@ -108,6 +108,7 @@ config BR2_RISCV_ABI_LP64
 config BR2_RISCV_ABI_LP64F
 	bool "lp64f"
 	depends on BR2_ARCH_IS_64 && BR2_RISCV_ISA_RVF
+	depends on BR2_USE_MMU
 
 config BR2_RISCV_ABI_LP64D
 	bool "lp64d"