Commit 63c93fac authored by Thomas Huth's avatar Thomas Huth
Browse files

pc-bios/s390-ccw: Optimize the s390-netboot.img for size 



The -O2 optimization flag is passed via CFLAGS to the firmware Makefile,
but in netbook.mak, we've got some rules that only use QEMU_CFLAGS for
compiling the libc and libnet from SLOF, so these files get compiled
without optimization so far. Use CFLAGS here, too, to create faster
and smaller code.

We can additionally save some more bytes in the firmware images by compi-
ling the code with -fno-asynchronous-unwind-tables. This will omit some
ELF sections (used for stack unwinding for example) from the image that
we do not need in the firmware.

Acked-by: default avatarChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: default avatarThomas Huth <thuth@redhat.com>
parent 0d8261b5

pc-bios/s390-ccw/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -15,6 +15,7 @@ OBJECTS = start.o main.o bootmap.o jump2ipl.o sclp.o menu.o \ 
QEMU_CFLAGS := $(filter -W%, $(QEMU_CFLAGS))

QEMU_CFLAGS += -ffreestanding -fno-delete-null-pointer-checks -msoft-float

QEMU_CFLAGS += -march=z900 -fPIE -fno-strict-aliasing

QEMU_CFLAGS += -fno-asynchronous-unwind-tables

QEMU_CFLAGS += $(call cc-option, $(QEMU_CFLAGS), -fno-stack-protector)

LDFLAGS += -Wl,-pie -nostdlib

pc-bios/s390-ccw/netboot.mak

+2 −2
Original line number Diff line number Diff line
@@ -19,7 +19,7 @@ s390-netboot.img: s390-netboot.elf 


# libc files:



LIBC_CFLAGS :=  $(QEMU_CFLAGS) $(LIBC_INC) $(LIBNET_INC)

LIBC_CFLAGS :=  $(QEMU_CFLAGS) $(CFLAGS) $(LIBC_INC) $(LIBNET_INC)



CTYPE_OBJS = isdigit.o isxdigit.o toupper.o

%.o : $(SLOF_DIR)/lib/libc/ctype/%.c
@@ -52,7 +52,7 @@ libc.a: $(LIBCOBJS) 


LIBNETOBJS := args.o dhcp.o dns.o icmpv6.o ipv6.o tcp.o udp.o bootp.o \

	      dhcpv6.o ethernet.o ipv4.o ndp.o tftp.o pxelinux.o

LIBNETCFLAGS := $(QEMU_CFLAGS) -DDHCPARCH=0x1F $(LIBC_INC) $(LIBNET_INC)

LIBNETCFLAGS := $(QEMU_CFLAGS) $(CFLAGS) -DDHCPARCH=0x1F $(LIBC_INC) $(LIBNET_INC)



%.o : $(SLOF_DIR)/lib/libnet/%.c

	$(call quiet-command,$(CC) $(LIBNETCFLAGS) -c -o $@ $<,"CC","$(TARGET_DIR)$@")