On Fri, Feb 26, 2016 at 06:08:46PM +0100, Laurent Vivier wrote:
> This patch allows to build tests for ppc64 little endian target
> (ppc64le) on big and little endian hosts.
>
> We add a new parameter to configure to select the endianness of the
> tests (--endian=little or --endian=big).
>
> I have built and tested big and little endian tests on a little
> endian host, a big endian host, with kvm_hv and kvm_pr, and on
> x86_64 with ppc64 as a TCG target.
>
> Signed-off-by: Laurent Vivier <lvivier@xxxxxxxxxx>
> ---
> v2: replace FIXUP_ENDIAN from linux by a home made version
> (B_BE and RETURN_FROM_BE)
>
> Makefile | 11 ++++++-----
> configure | 6 ++++++
> lib/powerpc/asm/ppc_asm.h | 36 ++++++++++++++++++++++++++++++++++++
> lib/ppc64/asm/io.h | 8 ++++++++
> lib/ppc64/asm/ppc_asm.h | 1 +
> powerpc/Makefile | 2 +-
> powerpc/Makefile.big | 21 +++++++++++++++++++++
> powerpc/Makefile.common | 18 ++++++++++--------
> powerpc/Makefile.little | 21 +++++++++++++++++++++
> powerpc/Makefile.ppc64 | 22 ----------------------
> powerpc/cstart64.S | 14 ++++++++++----
By renaming Makefile.ppc64 to Makefile.{little,big} we lose the
'ppc64' information. Since you've defined the ENDIAN config
variable, then how about just doing
ifeq ($(ENDIAN),little)
CFLAGS = -mlittle-endian
LDFLAGS = -EL
else
CFLAGS = -mbig-endian
LDFLAGS = -EB
endif
Or even just substitute $(ENDIAN) when you want "big"/"little",
such as in the CFLAGS.
> 11 files changed, 120 insertions(+), 40 deletions(-)
> create mode 100644 lib/powerpc/asm/ppc_asm.h
> create mode 100644 lib/ppc64/asm/ppc_asm.h
> create mode 100644 powerpc/Makefile.big
> create mode 100644 powerpc/Makefile.little
> delete mode 100644 powerpc/Makefile.ppc64
>
> diff --git a/Makefile b/Makefile
> index ddba941..8ed244a 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -40,12 +40,13 @@ include $(TEST_DIR)/Makefile
> cc-option = $(shell if $(CC) $(1) -S -o /dev/null -xc /dev/null \
> > /dev/null 2>&1; then echo "$(1)"; else echo "$(2)"; fi ;)
>
> -CFLAGS += -g
> -CFLAGS += $(autodepend-flags) -Wall
> -CFLAGS += $(call cc-option, -fomit-frame-pointer, "")
> -CFLAGS += $(call cc-option, -fno-stack-protector, "")
> -CFLAGS += $(call cc-option, -fno-stack-protector-all, "")
> +main_CFLAGS = -g
> +main_CFLAGS += $(autodepend-flags) -Wall
> +main_CFLAGS += $(call cc-option, -fomit-frame-pointer, "")
> +main_CFLAGS += $(call cc-option, -fno-stack-protector, "")
> +main_CFLAGS += $(call cc-option, -fno-stack-protector-all, "")
I guess this is because cc-option doesn't work well with cross-endian
compiling? Can we fix the function instead? In any case, do we have
drop '-g -Wall and -MMD -MF $(dir $*).$(notdir $*).d' too?
>
> +CFLAGS += $(main_CFLAGS)
> CXXFLAGS += $(CFLAGS)
>
> autodepend-flags = -MMD -MF $(dir $*).$(notdir $*).d
> diff --git a/configure b/configure
> index a685cca..0043ee9 100755
> --- a/configure
> +++ b/configure
> @@ -10,6 +10,7 @@ ar=ar
> arch=`uname -m | sed -e 's/i.86/i386/;s/arm.*/arm/;s/ppc64.*/ppc64/'`
> host=$arch
> cross_prefix=
> +endian=big # default for ppc64, the only user
If we default to 'little', then we don't have to worry about the current
architectures using it. Is big the better default for some reason? Also,
as both big and little work on both big and little, then maybe we should
require it to be explicitly added (to make sure the user knows which
they're using).
>
> usage() {
> cat <<-EOF
> @@ -23,6 +24,7 @@ usage() {
> --ld=LD ld linker to use ($ld)
> --prefix=PREFIX where to install things ($prefix)
> --kerneldir=DIR kernel build directory for kvm.h ($kerneldir)
> + --endian=ENDIAN endianness to compile for (little or big)
> EOF
> exit 1
> }
> @@ -50,6 +52,9 @@ while [[ "$1" = -* ]]; do
> --cross-prefix)
> cross_prefix="$arg"
> ;;
> + --endian)
> + endian="$arg"
> + ;;
Looks like a inconsistent whitespace here (should use tabs).
> --cc)
> cc="$arg"
> ;;
> @@ -139,4 +144,5 @@ AR=$cross_prefix$ar
> API=$api
> TEST_DIR=$testdir
> FIRMWARE=$firmware
> +ENDIAN=$endian
> EOF
> diff --git a/lib/powerpc/asm/ppc_asm.h b/lib/powerpc/asm/ppc_asm.h
> new file mode 100644
> index 0000000..f0ab241
> --- /dev/null
> +++ b/lib/powerpc/asm/ppc_asm.h
> @@ -0,0 +1,36 @@
> +#ifndef _ASMPOWERPC_PPC_ASM_H
> +#define _ASMPOWERPC_PPC_ASM_H
Adding this file is a good idea, we should probably move
LOAD_REG_IMMEDIATE and LOAD_REG_ADDR here too.
> +
> +#if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
> +
> +#define B_BE(addr) \
> + mtctr addr; \
> + nop; \
> + bctr
> +
> +#define RETURN_FROM_BE
> +
> +#elif __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
> +
> +#define B_BE(addr) \
> + mfmsr r11; \
> + xori r11,r11,1; \
> + mtsrr0 addr; \
> + mtsrr1 r11; \
> + rfid; \
> + b .
> +
> +#define RETURN_FROM_BE \
> + .long 0x05000048; /* bl . + 4 */ \
> + .long 0xa602487d; /* mflr r10 */ \
> + .long 0x20004a39; /* addi r10,r10,32 */ \
> + .long 0xa600607d; /* mfmsr r11 */ \
> + .long 0x01006b69; /* xori r11,r11,1 */ \
> + .long 0xa6035a7d; /* mtsrr0 r10 */ \
> + .long 0xa6037b7d; /* mtsrr1 r11 */ \
> + .long 0x2400004c; /* rfid */ \
> + .long 0x00000048; /* b . */ \
I think we only need RETURN_FROM_BE. B_BE is currently only used
in enter_rtas, where it's fine now, but based on some of David's
comments, I think we may eventually want to change even more
state before the rtas call, which means the BE version will need
the rfid anyway. Thus we can just drop the LE version straight into
enter_rtas, replacing the xor with explicitly setting BE mode.
> +
> +#endif /* __BYTE_ORDER__ */
> +
> +#endif /* _ASMPOWERPC_PPC_ASM_H */
> diff --git a/lib/ppc64/asm/io.h b/lib/ppc64/asm/io.h
> index c0801d4..4f2c31b 100644
> --- a/lib/ppc64/asm/io.h
> +++ b/lib/ppc64/asm/io.h
> @@ -1,5 +1,13 @@
> #ifndef _ASMPPC64_IO_H_
> #define _ASMPPC64_IO_H_
> +
> +#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
> +#define __cpu_is_be() (0)
> +#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
> #define __cpu_is_be() (1)
> +#else
> +#error Undefined byte order
> +#endif
> +
> #include <asm-generic/io.h>
> #endif
> diff --git a/lib/ppc64/asm/ppc_asm.h b/lib/ppc64/asm/ppc_asm.h
> new file mode 100644
> index 0000000..e3929ee
> --- /dev/null
> +++ b/lib/ppc64/asm/ppc_asm.h
> @@ -0,0 +1 @@
> +#include "../../powerpc/asm/ppc_asm.h"
> diff --git a/powerpc/Makefile b/powerpc/Makefile
> index 369a38b..cc39a09 100644
> --- a/powerpc/Makefile
> +++ b/powerpc/Makefile
> @@ -1 +1 @@
> -include $(TEST_DIR)/Makefile.$(ARCH)
> +include $(TEST_DIR)/Makefile.$(ENDIAN)
> diff --git a/powerpc/Makefile.big b/powerpc/Makefile.big
> new file mode 100644
> index 0000000..d81c52d
> --- /dev/null
> +++ b/powerpc/Makefile.big
> @@ -0,0 +1,21 @@
> +#
> +# ppc64 big-endian makefile
> +#
> +# Authors: Andrew Jones <drjones@xxxxxxxxxx>
> +#
> +bits = 64
> +
> +arch_CFLAGS = -mbig-endian
> +arch_LDFLAGS = -EB
> +
> +cstart.o = $(TEST_DIR)/cstart64.o
> +reloc.o = $(TEST_DIR)/reloc64.o
> +cflatobjs += lib/ppc64/spinlock.o
> +
> +# ppc64 specific tests
> +tests =
> +
> +include $(TEST_DIR)/Makefile.common
> +
> +arch_clean: powerpc_clean
> + $(RM) lib/ppc64/.*.d
> diff --git a/powerpc/Makefile.common b/powerpc/Makefile.common
> index cc27ac8..b088af6 100644
> --- a/powerpc/Makefile.common
> +++ b/powerpc/Makefile.common
> @@ -11,14 +11,15 @@ all: $(TEST_DIR)/boot_rom.bin test_cases
>
> ##################################################################
>
> -CFLAGS += $(arch_CFLAGS)
> -CFLAGS += -std=gnu99
> -CFLAGS += -ffreestanding
> -CFLAGS += -Wextra
> -CFLAGS += -O2
> -CFLAGS += -I lib -I lib/libfdt
> -CFLAGS += -Wa,-mregnames
> -CFLAGS += -fpie
> +common_CFLAGS = -std=gnu99
> +common_CFLAGS += -ffreestanding
> +common_CFLAGS += -Wextra
> +common_CFLAGS += -O2
> +common_CFLAGS += -I lib -I lib/libfdt
> +common_CFLAGS += -Wa,-mregnames
> +common_CFLAGS += -fpie
> +
> +CFLAGS += $(arch_CFLAGS) $(common_CFLAGS)
I'm not sure what we gain by renaming to common_CFLAGS. Doesn't just
%.elf: CFLAGS += $(arch_CFLAGS)
work?
>
> asm-offsets = lib/$(ARCH)/asm-offsets.h
> include scripts/asm-offsets.mak
> @@ -48,6 +49,7 @@ $(TEST_DIR)/boot_rom.bin: $(TEST_DIR)/boot_rom.elf
> dd if=/dev/zero of=$@ bs=256 count=1
> $(OBJCOPY) -O binary $^ >(cat - >>$@)
>
> +$(TEST_DIR)/boot_rom.elf: CFLAGS = -mbig-endian $(common_CFLAGS) $(main_CFLAGS)
And just
$(TEST_DIR)/boot_rom.elf: CFLAGS += -mbig-endian
> $(TEST_DIR)/boot_rom.elf: $(TEST_DIR)/boot_rom.o
> $(LD) -EB -nostdlib -Ttext=0x100 --entry=start --build-id=none -o $@ $<
>
> diff --git a/powerpc/Makefile.little b/powerpc/Makefile.little
> new file mode 100644
> index 0000000..c37d2fc
> --- /dev/null
> +++ b/powerpc/Makefile.little
> @@ -0,0 +1,21 @@
> +#
> +# ppc64 little-endian makefile
> +#
> +# Authors: Andrew Jones <drjones@xxxxxxxxxx>
> +#
> +bits = 64
> +
> +arch_CFLAGS = -mlittle-endian
> +arch_LDFLAGS = -EL
> +
> +cstart.o = $(TEST_DIR)/cstart64.o
> +reloc.o = $(TEST_DIR)/reloc64.o
> +cflatobjs += lib/ppc64/spinlock.o
> +
> +# ppc64 specific tests
> +tests =
> +
> +include $(TEST_DIR)/Makefile.common
> +
> +arch_clean: powerpc_clean
> + $(RM) lib/ppc64/.*.d
> diff --git a/powerpc/Makefile.ppc64 b/powerpc/Makefile.ppc64
> deleted file mode 100644
> index 1cf277e..0000000
> --- a/powerpc/Makefile.ppc64
> +++ /dev/null
> @@ -1,22 +0,0 @@
> -#
> -# ppc64 makefile
> -#
> -# Authors: Andrew Jones <drjones@xxxxxxxxxx>
> -#
> -bits = 64
> -ldarch = elf64-powerpc
> -
> -arch_CFLAGS = -mbig-endian
> -arch_LDFLAGS = -EB
> -
> -cstart.o = $(TEST_DIR)/cstart64.o
> -reloc.o = $(TEST_DIR)/reloc64.o
> -cflatobjs += lib/ppc64/spinlock.o
> -
> -# ppc64 specific tests
> -tests =
> -
> -include $(TEST_DIR)/Makefile.common
> -
> -arch_clean: powerpc_clean
> - $(RM) lib/ppc64/.*.d
> diff --git a/powerpc/cstart64.S b/powerpc/cstart64.S
> index f5530fb..60557a9 100644
> --- a/powerpc/cstart64.S
> +++ b/powerpc/cstart64.S
> @@ -7,6 +7,7 @@
> */
> #define __ASSEMBLY__
> #include <asm/hcall.h>
> +#include <asm/ppc_asm.h>
>
> #define LOAD_REG_IMMEDIATE(reg,expr) \
> lis reg,(expr)@highest; \
> @@ -25,6 +26,7 @@
> */
> .globl start
> start:
> + RETURN_FROM_BE
> /*
> * We were loaded at QEMU's kernel load address, but we're not
> * allowed to link there due to how QEMU deals with linker VMAs,
> @@ -93,11 +95,15 @@ halt:
> enter_rtas:
> mflr r0
> std r0, 16(r1)
> +
> + LOAD_REG_ADDR(r10,rtas_return_loc)
> + mtlr r10
> +
> LOAD_REG_ADDR(r10, rtas_blob)
> -//FIXME: change this bctrl to an rtas-prep, rfid, rtas-return sequence
> - mtctr r10
> - nop
> - bctrl
> + B_BE(r10)
> +
> +rtas_return_loc:
> + RETURN_FROM_BE
> ld r0, 16(r1)
> mtlr r0
> blr
Besides my earlier comment about always needing rfid to prep for the
rtas call (which my FIXUP comment here poorly indicated), then this
looks good to me. Although I'm not sure I like the name RETURN_FROM_BE,
as sometimes we're returning to LE, and sometimes we're not. In the
not case, it's a bit confusing.
Thanks,
drew
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