Hi Lukas,
On Sat, Oct 20, 2018 at 6:10 AM Lukas Auer
wrote:
>
> RISC-V has two code models, medium low (medlow) and medium any (medany).
> Medlow limits addressable memory to a single 2 GiB range between the
> absolute addresses -2 GiB and +2 GiB. Medany limits addressable memory
> to any single 2 GiB address range.
> By default, medlow is selected on 32-bit systems and medany on 64-bit
> systems. This matches the configuration in Linux.
>
> The -mcmodel compiler flag is selected according to the Kconfig
> configuration.
>
> Signed-off-by: Lukas Auer
> ---
>
> arch/riscv/Kconfig | 19 +++
> arch/riscv/Makefile | 7 +--
> 2 files changed, 24 insertions(+), 2 deletions(-)
>
> diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
> index e15329c35e..ce07fb4b55 100644
> --- a/arch/riscv/Kconfig
> +++ b/arch/riscv/Kconfig
> @@ -38,6 +38,25 @@ config ARCH_RV64I
>
> endchoice
>
> +choice
> + prompt "Code Model"
> + default CMODEL_MEDLOW if 32BIT
> + default CMODEL_MEDANY if 64BIT
> +
> +config CMODEL_MEDLOW
> + bool "medium low code model"
> + help
> + U-Boot and its statically defined symbols must lie within a single
> 2 GiB
> + address range and must lie between absolute addresses -2 GiB and +2
> GiB.
> +
> +config CMODEL_MEDANY
> + bool "medium any code model"
> + help
> + U-Boot and its statically defined symbols must be within any single
> 2 GiB
> + address range.
> +
> +endchoice
> +
> config RISCV_ISA_C
> bool "Emit compressed instructions"
> default y
> diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile
> index 6fb292d0b4..da6e50bd14 100644
> --- a/arch/riscv/Makefile
> +++ b/arch/riscv/Makefile
> @@ -13,8 +13,11 @@ riscv-mabi-$(CONFIG_ARCH_RV32I) := ilp32
>
> arch-y := -march=$(riscv-march-y) -mabi=$(riscv-mabi-y)
>
> -PLATFORM_CPPFLAGS += $(arch-y)
> -CFLAGS_EFI += $(arch-y)
> +cmodel-$(CONFIG_CMODEL_MEDLOW) := -mcmodel=medlow
> +cmodel-$(CONFIG_CMODEL_MEDANY) := -mcmodel=medany
> +
> +PLATFORM_CPPFLAGS += $(arch-y) $(cmodel-y)
> +CFLAGS_EFI += $(arch-y) $(cmodel-y)
>
> head-y := arch/riscv/cpu/start.o
See my comments for patch [07/30]. We can do similar thing to the code model.
Regards,
Bin
___
U-Boot mailing list
U-Boot@lists.denx.de
https://lists.denx.de/listinfo/u-boot
