[PATCH v2 1/3] riscv: nommu: remove PAGE_OFFSET hardcoding

Jisheng Zhang
2024-04-06T11:35:30Z

Currently, PAGE_OFFSET is hardcoded as 0x8000_0000, it works fine since
there's only one nommu platform in the mainline. However, there are
many cases where the (S)DRAM base address isn't 0x8000_0000, so remove
the hardcoding value, and introduce DRAM_BASE which will be set by
users during configuring. DRAM_BASE is 0x8000_0000 by default.

Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
---
arch/riscv/Kconfig | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index 7895c77545f1..b4af1df86352 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -247,10 +247,16 @@ config MMU
Select if you want MMU-based virtualised addressing space
support by paged memory management. If unsure, say 'Y'.

+if !MMU
+config DRAM_BASE
+ hex '(S)DRAM Base Address'
+ default 0x80000000
+endif
+
config PAGE_OFFSET
hex
default 0xC0000000 if 32BIT && MMU
- default 0x80000000 if !MMU
+ default DRAM_BASE if !MMU
default 0xff60000000000000 if 64BIT

config KASAN_SHADOW_OFFSET