Re: [U-Boot] [PATCH] riscv: add Kconfig entries for the F and D ISA extensions support

Hi Eric,

On Tue, May 21, 2019 at 3:18 PM Eric Lin tesheng@andestech.com wrote:

This patch add Kconfig entries for the F (Single-Precision)

adds

and D (Double-Precision) floating point instruction-set extensions.

Could you please provide reason that why U-Boot has to be compiled using F/D extension?

Signed-off-by: Eric Lin tesheng@andestech.com

arch/riscv/Kconfig | 8 ++++++++ arch/riscv/Makefile | 12 ++++++++---- 2 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 362f3cdc65..a8031fa230 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -91,6 +91,14 @@ config RISCV_ISA_C when building U-Boot, which results in compressed instructions in the U-Boot binary.

+config RISCV_ISA_F

•   bool "Emit Floating-point instructions"
  

•   default n
  

this can be dropped as default is n

•   help
  

•     Adds "F" to the ISA subsets that the toolchain is allowed to emit
  

•     when building U-Boot, which results in Single and Double-precision instructions
  

This does not match what the config name says. The config name is for F and it cannot indicate both F and D here.

•     in the U-Boot binary.
  

config RISCV_ISA_A def_bool y

diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile index 0b80eb8d86..87ec0ea4b5 100644 --- a/arch/riscv/Makefile +++ b/arch/riscv/Makefile @@ -5,15 +5,19 @@

ifeq ($(CONFIG_ARCH_RV64I),y) ARCH_BASE = rv64im

•   ABI = lp64
  

•   ABI := lp64
  

endif ifeq ($(CONFIG_ARCH_RV32I),y) ARCH_BASE = rv32im

•   ABI = ilp32
  

•   ABI := ilp32
  

endif ifeq ($(CONFIG_RISCV_ISA_A),y) ARCH_A = a endif +ifeq ($(CONFIG_RISCV_ISA_F),y)

•   ARCH_F = fd
  

•   ABI := $(ABI)d
  

+endif ifeq ($(CONFIG_RISCV_ISA_C),y) ARCH_C = c endif @@ -24,8 +28,8 @@ ifeq ($(CONFIG_CMODEL_MEDANY),y) CMODEL = medany endif

-ARCH_FLAGS = -march=$(ARCH_BASE)$(ARCH_A)$(ARCH_C) -mabi=$(ABI) \

•        -mcmodel=$(CMODEL)
  

+ARCH_FLAGS = -march=$(ARCH_BASE)$(ARCH_A)$(ARCH_F)$(ARCH_C) -mabi=$(ABI) \

•                            -mcmodel=$(CMODEL)
  
  

PLATFORM_CPPFLAGS += $(ARCH_FLAGS) CFLAGS_EFI += $(ARCH_FLAGS) --

Regards, Bin