qemu/pc-bios/optionrom/Makefile
Marcus Hähnel 48972f8cad optionrom: add a DMA-enabled multiboot ROM
Add a new option rom for the multiboot loader, using DMA transfers to copy
data instead of "rep insb".

This significantly lowers QEMU's startup latency by a factor of about 40,
for example, going from 30sec to 0.8sec when loading modules of 120MB
in size.

Signed-off-by: Marcus Hähnel <marcus.haehnel@kernkonzept.com>
Signed-off-by: Adam Lackorzynski <adam@l4re.org>
[Modified to keep the non-DMA code depending on #ifdef USE_FW_CFG_DMA;
 do not write below stack. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-11-02 15:57:27 +01:00

70 lines
2.2 KiB
Makefile

include config.mak
SRC_DIR := $(TOPSRC_DIR)/pc-bios/optionrom
VPATH = $(SRC_DIR)
all: multiboot.bin multiboot_dma.bin linuxboot.bin linuxboot_dma.bin kvmvapic.bin pvh.bin
# Dummy command so that make thinks it has done something
@true
include ../../config-host.mak
CFLAGS = -O2 -g
quiet-command = $(if $(V),$1,$(if $(2),@printf " %-7s %s\n" $2 $3 && $1, @$1))
cc-option = $(if $(shell $(CC) $1 -c -o /dev/null -xc /dev/null >/dev/null 2>&1 && echo OK), $1, $2)
override CFLAGS += -march=i486 -Wall
# Flags for dependency generation
override CPPFLAGS += -MMD -MP -MT $@ -MF $(@D)/$(*F).d
override CFLAGS += $(filter -W%, $(QEMU_CFLAGS))
override CFLAGS += $(CFLAGS_NOPIE) -ffreestanding -I$(TOPSRC_DIR)/include
override CFLAGS += $(call cc-option, -fno-stack-protector)
override CFLAGS += $(call cc-option, -m16)
ifeq ($(filter -m16, $(CFLAGS)),)
# Attempt to work around compilers that lack -m16 (GCC <= 4.8, clang <= ??)
# On GCC we add -fno-toplevel-reorder to keep the order of asm blocks with
# respect to the rest of the code. clang does not have -fno-toplevel-reorder,
# but it places all asm blocks at the beginning and we're relying on it for
# the option ROM header. So just force clang not to use the integrated
# assembler, which doesn't support .code16gcc.
override CFLAGS += $(call cc-option, -fno-toplevel-reorder)
override CFLAGS += $(call cc-option, -no-integrated-as)
override CFLAGS += -m32 -include $(SRC_DIR)/code16gcc.h
endif
Wa = -Wa,
override ASFLAGS += -32
override CFLAGS += $(call cc-option, $(Wa)-32)
LD_I386_EMULATION ?= elf_i386
override LDFLAGS = -m $(LD_I386_EMULATION) -T $(SRC_DIR)/flat.lds
pvh.img: pvh.o pvh_main.o
%.o: %.S
$(call quiet-command,$(CPP) $(CPPFLAGS) -c -o - $< | $(AS) $(ASFLAGS) -o $@,"AS","$@")
%.o: %.c
$(call quiet-command,$(CC) $(CPPFLAGS) $(CFLAGS) -c $< -o $@,"CC","$@")
%.img: %.o
$(call quiet-command,$(LD) $(LDFLAGS) -s -o $@ $^,"BUILD","$@")
%.raw: %.img
$(call quiet-command,$(OBJCOPY) -O binary -j .text $< $@,"BUILD","$@")
%.bin: %.raw
$(call quiet-command,$(PYTHON) $(TOPSRC_DIR)/scripts/signrom.py $< $@,"SIGN","$@")
include $(wildcard *.d)
clean:
rm -f *.o *.d *.raw *.img *.bin *~
# suppress auto-removal of intermediate files
.SECONDARY:
.PHONY: all clean