Unverified Commit e5577937 authored by Atish Patra's avatar Atish Patra Committed by Palmer Dabbelt
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RISC-V: Fix maximum allowed phsyical memory for RV32 



Linux kernel can only map 1GB of address space for RV32 as the page offset
is set to 0xC0000000. The current description in the Kconfig is confusing
as it indicates that RV32 can support 2GB of physical memory. That is
simply not true for current kernel. In future, a 2GB split support can be
added to allow 2GB physical address space.

Reviewed-by: default avatarAnup Patel <anup@brainfault.org>
Signed-off-by: default avatarAtish Patra <atish.patra@wdc.com>
Signed-off-by: default avatarPalmer Dabbelt <palmerdabbelt@google.com>
parent abb8e86b

arch/riscv/Kconfig

+4 −2
Original line number Diff line number Diff line
@@ -137,7 +137,7 @@ config PA_BITS 


config PAGE_OFFSET

	hex

	default 0xC0000000 if 32BIT && MAXPHYSMEM_2GB

	default 0xC0000000 if 32BIT && MAXPHYSMEM_1GB

	default 0x80000000 if 64BIT && !MMU

	default 0xffffffff80000000 if 64BIT && MAXPHYSMEM_2GB

	default 0xffffffe000000000 if 64BIT && MAXPHYSMEM_128GB
@@ -247,10 +247,12 @@ config MODULE_SECTIONS 


choice

	prompt "Maximum Physical Memory"

	default MAXPHYSMEM_2GB if 32BIT

	default MAXPHYSMEM_1GB if 32BIT

	default MAXPHYSMEM_2GB if 64BIT && CMODEL_MEDLOW

	default MAXPHYSMEM_128GB if 64BIT && CMODEL_MEDANY



	config MAXPHYSMEM_1GB

		bool "1GiB"

	config MAXPHYSMEM_2GB

		bool "2GiB"

	config MAXPHYSMEM_128GB