Hi Bin,
On Mon, 2018-10-22 at 15:21 +0800, Bin Meng wrote:
Hi Lukas,
On Sat, Oct 20, 2018 at 6:09 AM Lukas Auer lukas.auer@aisec.fraunhofer.de wrote:
Use the new Kconfig entries to construct the ISA string for the -march compiler flag. The -mabi compiler flag is selected based on the base integer instruction set.
With this change, the C (compressed instructions) ISA extension is now enabled for all boards with CONFIG_RISCV_ISA_C set. Buildman reports a decrease in binary size of 71590 bytes.
Signed-off-by: Lukas Auer lukas.auer@aisec.fraunhofer.de
arch/riscv/Makefile | 13 +++++++++++++ arch/riscv/config.mk | 4 ---- 2 files changed, 13 insertions(+), 4 deletions(-)
diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile index 8fb6a889d8..6fb292d0b4 100644 --- a/arch/riscv/Makefile +++ b/arch/riscv/Makefile @@ -3,6 +3,19 @@ # Copyright (C) 2017 Andes Technology Corporation. # Rick Chen, Andes Technology Corporation rick@andestech.com
+riscv-march-$(CONFIG_ARCH_RV32I) := rv32im +riscv-march-$(CONFIG_ARCH_RV64I) := rv64im +riscv-march-$(CONFIG_RISCV_ISA_A) := $(riscv-march-y)a +riscv-march-$(CONFIG_RISCV_ISA_C) := $(riscv-march-y)c
+riscv-mabi-$(CONFIG_ARCH_RV64I) := lp64 +riscv-mabi-$(CONFIG_ARCH_RV32I) := ilp32
+arch-y := -march=$(riscv-march-y) -mabi=$(riscv-mabi-y)
+PLATFORM_CPPFLAGS += $(arch-y) +CFLAGS_EFI += $(arch-y)
The concept of this patch is good. However the usage of := is a bit odd, since it makes people think the latter will override the former one, however it is not.
Can we get rid of these riscv-mach-xxx, instead using something like this:
ifeq ($(CONFIG_RISCV_ISA_A),y) ARCH_A = a endif ifeq ($(CONFIG_RISCV_ISA_C),y) ARCH_C = c endif
ifeq ($(CONFIG_ARCH_RV32I),y) BITS = 32 ABI_I = i endif ifeq ($(CONFIG_ARCH_RV64I),y) BITS = 64 endif
PLATFORM_CPPFLAGS += -march=rv$(BITS)im$(ARCH_A)$(ARCH_C) -mabi=$(ABI_I)lp$(BITS)
That makes sense. Yes I can change it to something like that. One small change I would do is to try and keep any constant ISA / ABI strings (so rv and im) out of PLATFORM_CPPFLAGS to keep the configuration more in one place. So something like this. What do you think?
ifeq ($(CONFIG_ARCH_RV32I),y) ARCH_BASE = rv32im ABI = ilp32 endif ifeq ($(CONFIG_ARCH_RV64I),y) ARCH_BASE = rv64im ABI = lp64 endif
PLATFORM_CPPFLAGS += -march=$(ARCH_BASE)$(ARCH_A)$(ARCH_C) -mabi=$(ABI)
Thanks, Lukas
head-y := arch/riscv/cpu/start.o
libs-y += arch/riscv/cpu/ diff --git a/arch/riscv/config.mk b/arch/riscv/config.mk index ed9eb0c24c..9088b9ef2c 100644 --- a/arch/riscv/config.mk +++ b/arch/riscv/config.mk @@ -14,16 +14,12 @@ 64bit-emul := elf64lriscv
ifdef CONFIG_32BIT -PLATFORM_CPPFLAGS += -march=rv32ima -mabi=ilp32 PLATFORM_LDFLAGS += -m $(32bit-emul) -CFLAGS_EFI += -march=rv32ima -mabi=ilp32 EFI_LDS := elf_riscv32_efi.lds endif
ifdef CONFIG_64BIT -PLATFORM_CPPFLAGS += -march=rv64ima -mabi=lp64 PLATFORM_LDFLAGS += -m $(64bit-emul) -CFLAGS_EFI += -march=rv64ima -mabi=lp64 EFI_LDS := elf_riscv64_efi.lds endif
--
Regards, Bin