From:   Jesse Taube <mr.bossman075@gmail.com>
To:     linux-riscv@lists.infradead.org
Cc:     linux-kernel@vger.kernel.org,
        Jesse Taube <Mr.Bossman075@gmail.com>,
        Yimin Gu <ustcymgu@gmail.com>,
        Waldemar Brodkorb <wbx@openadk.org>,
        Albert Ou <aou@eecs.berkeley.edu>,
        Palmer Dabbelt <palmer@dabbelt.com>,
        Paul Walmsley <paul.walmsley@sifive.com>
Subject: [PATCH v2 2/3] riscv: Kconfig: Allow RV32 to build with no MMU
Date:   Sun, 12 Feb 2023 15:55:05 -0500
Message-Id: <20230212205506.1992714-3-Mr.Bossman075@gmail.com>
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From: Yimin Gu <ustcymgu@gmail.com>

Some RISC-V 32bit cores do not have an MMU, and the kernel should be
able to build for them. This patch enables the RV32 to be built with
no MMU support.

Signed-off-by: Yimin Gu <ustcymgu@gmail.com>
CC: Jesse Taube <Mr.Bossman075@gmail.com>
Tested-by: Waldemar Brodkorb <wbx@openadk.org>
Signed-off-by: Jesse Taube <Mr.Bossman075@gmail.com>
---
 arch/riscv/Kconfig | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index 59d18881f35b..49759dbe6a8f 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -163,8 +163,8 @@ config MMU
 
 config PAGE_OFFSET
 	hex
-	default 0xC0000000 if 32BIT
-	default 0x80000000 if 64BIT && !MMU
+	default 0xC0000000 if 32BIT && MMU
+	default 0x80000000 if !MMU
 	default 0xff60000000000000 if 64BIT
 
 config KASAN_SHADOW_OFFSET
@@ -262,7 +262,6 @@ config ARCH_RV32I
 	select GENERIC_LIB_ASHRDI3
 	select GENERIC_LIB_LSHRDI3
 	select GENERIC_LIB_UCMPDI2
-	select MMU
 
 config ARCH_RV64I
 	bool "RV64I"
-- 
2.39.0