From:   Jesse Taube <mr.bossman075@gmail.com>
To:     linux-riscv@lists.infradead.org
Cc:     linux-clk@vger.kernel.org, linux-kernel@vger.kernel.org,
        Jesse Taube <Mr.Bossman075@gmail.com>,
        Yimin Gu <ustcymgu@gmail.com>,
        Damien Le Moal <damien.lemoal@wdc.com>,
        Stephen Boyd <sboyd@kernel.org>,
        Michael Turquette <mturquette@baylibre.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 v3 2/3] riscv: Kconfig: Allow RV32 to build with no MMU
Date:   Tue, 28 Feb 2023 19:26:56 -0500
Message-Id: <20230301002657.352637-3-Mr.Bossman075@gmail.com>
In-Reply-To: <20230301002657.352637-1-Mr.Bossman075@gmail.com>
References: <20230301002657.352637-1-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>
---
V1->V2:
 - Fix typo in commit description
V2->V3:
 - No change
---
 arch/riscv/Kconfig | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index c5e42cc37604..d1f661425790 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -177,8 +177,8 @@ 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
@@ -279,7 +279,6 @@ 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