kwboot: UART booting with bin_hdr u-boot (Marvell Armada 385)

Sat Jan 14 22:43:59 CET 2023

On Saturday 14 January 2023 13:35:08 Tony Dinh wrote:
> Hi Pali,
> 
> On Fri, Jan 13, 2023 at 5:32 PM Pali Rohár <pali at kernel.org> wrote:
> >
> > On Wednesday 11 January 2023 21:56:41 Pali Rohár wrote:
> > > On Wednesday 11 January 2023 12:44:45 Tony Dinh wrote:
> > > > Hi Pali,
> > > >
> > > > On Wed, Jan 11, 2023 at 12:04 AM Pali Rohár <pali at kernel.org> wrote:
> > > > >
> > > > > On Tuesday 10 January 2023 21:07:45 Tony Dinh wrote:
> > > > > > Hi Pali,
> > > > > >
> > > > > > I got burned for being lazy :) it turned out that the mix of #ifdef
> > > > > > and #if defined was the problem. Just stepped away and came back for a
> > > > > > few minutes and I can see that I just need to define the CONFIG_DDR4
> > > > > > properly in arch/arm/mach-mvebu/Kconfig and build it to pass the
> > > > > > CONFIG_DDR4 stuff.
> > > > > >
> > > > > > One more small hurdle after that was CONFIG_USE_PRIVATE_LIBGCC must be
> > > > > > undefined for it to build (so I am using
> > > > > > /usr/lib/gcc/arm-linux-gnueabi/10/libgcc.a, and not using
> > > > > > arch/arm/lib/lib.a)
> > > > >
> > > > > Hello! It is normally a good idea to unset CONFIG_USE_PRIVATE_LIBGCC
> > > > > unless you have compiled gcc for target CPU.
> > > >
> > > > CONFIG_USE_PRIVATE_LIBGCC was set as a default for ARM target, since
> > > > u-boot has arch/arm/lib/lib.a. But using arch/arm/lib/lib.a I got
> > > > several build errors like these:
> > > >
> > > > ld.bfd: drivers/ddr/marvell/a38x/mv_ddr4_training_calibration.o: in
> > > > function `mv_ddr4_copt_get':
> > > > /usr/src/u-boot/drivers/ddr/marvell/a38x/mv_ddr4_training_calibration.c:809:
> > > > undefined reference to `__aeabi_i2d'
> > > > ld.bfd: /usr/src/u-boot/drivers/ddr/marvell/a38x/mv_ddr4_training_calibration.c:809:
> > > > undefined reference to `__aeabi_dmul'
> > > > ld.bfd: /usr/src/u-boot/drivers/ddr/marvell/a38x/mv_ddr4_training_calibration.c:809:
> > > > undefined reference to `__aeabi_d2uiz'
> > >
> > > This looks like a bug in that training code. I would need to see source
> > > code, so I can figure out how to fix it.
> >
> > Have you solved this issue? Or if not, can you show what you had on that
> > problematic line 809?
> 
> No, I have not and actually have no idea what that code does! And I
> thought you recognized the error, so I submitted the DDR4 patch so you
> can compile and see the error. Here is the code snipet, the error is
> now at 717.
> 
> # grep -n10 PBS_VALUE_FACTOR
> /usr/src/u-boot-master/drivers/ddr/marvell/a38x/mv_ddr4_training_calibration.c
> 704- u8 copt_val;
> 705- u8 dq_idx;
> 706- u8 center_zone_max_low = 0;
> 707- u8 center_zone_min_high = 128;
> 708- u8 vw_zone_max_low = 0;
> 709- u8 vw_zone_min_high = 128;
> 710- u8 min_vw = 63; /* minimum valid window between all bits */
> 711- u8 center_low_el;
> 712- u8 center_high_el;
> 713-
> 714: /* lambda calculated as D * PBS_VALUE_FACTOR / d */
> 715- //printf("Copt::Debug::\t");
> 716- for (dq_idx = 0; dq_idx < 8; dq_idx++) {
> 717- center_per_dq[dq_idx] = 0.5 * (vw_h[dq_idx] + vw_l[dq_idx]);
> 718- vw_per_dq[dq_idx] = 1 + (vw_h[dq_idx] - vw_l[dq_idx]);
> 719- if (min_vw > vw_per_dq[dq_idx])
> 720- min_vw = vw_per_dq[dq_idx];
> 721- }
> 722-
> 723- /* calculate center zone */
> 724- for (dq_idx = 0; dq_idx < 8; dq_idx++) {

Haha! That is pretty simple. On line 717 you have fractional number 0.5
which is represented by floating point and all numeric operation on that
line are done as floating point.

U-Boot and kernel does not floating point HW and instruct compiler to
replace all floating point operations by function calls (which implement
software floating point support).

U-Boot (for very good reasons) do not implement any floating point
operations.

Fix should be very simple, use only integer operations. So replace

  0.5 * something

by:

  something / 2

And check if it compiles and if it works.

I'm surprised that Marvell was trying to do floating point...

> Here are the build errors with the current code.
> 
> <BEGIN ERRORS BUILD LOG >
>   rm -f spl/common/spl/built-in.o; ar cDPrsT spl/common/spl/built-in.o
> spl/common/spl/spl.o spl/common/spl/spl_bootrom.o
> spl/common/spl/spl_spi.o
>   ( cd spl && ld.bfd  -T u-boot-spl.lds --gc-sections -Bstatic
> --gc-sections  --no-dynamic-linker --build-id=none -Ttext 0x40000030
> arch/arm/cpu/armv7/start.o --whole-archive
> arch/arm/mach-mvebu/built-in.o arch/arm/cpu/armv7/built-in.o
> arch/arm/cpu/built-in.o arch/arm/lib/built-in.o
> board/thecus/n2350/built-in.o common/spl/built-in.o
> common/init/built-in.o boot/built-in.o common/built-in.o
> cmd/built-in.o env/built-in.o lib/built-in.o disk/built-in.o
> drivers/built-in.o dts/built-in.o fs/built-in.o  --no-whole-archive
> arch/arm/lib/eabi_compat.o arch/arm/lib/lib.a -Map u-boot-spl.map -o
> u-boot-spl )
> ld.bfd: drivers/ddr/marvell/a38x/mv_ddr4_training_calibration.o: in
> function `mv_ddr4_copt_get':
> /usr/src/u-boot-master/drivers/ddr/marvell/a38x/mv_ddr4_training_calibration.c:717:
> undefined reference to `__aeabi_i2d'
> ld.bfd: /usr/src/u-boot-master/drivers/ddr/marvell/a38x/mv_ddr4_training_calibration.c:717:
> undefined reference to `__aeabi_dmul'
> ld.bfd: /usr/src/u-boot-master/drivers/ddr/marvell/a38x/mv_ddr4_training_calibration.c:717:
> undefined reference to `__aeabi_d2uiz'
> ld.bfd: /usr/src/u-boot-master/drivers/ddr/marvell/a38x/mv_ddr4_training_calibration.c:757:
> undefined reference to `__aeabi_i2d'
> ld.bfd: /usr/src/u-boot-master/drivers/ddr/marvell/a38x/mv_ddr4_training_calibration.c:757:
> undefined reference to `__aeabi_i2d'
> ld.bfd: /usr/src/u-boot-master/drivers/ddr/marvell/a38x/mv_ddr4_training_calibration.c:757:
> undefined reference to `__aeabi_dmul'
> ld.bfd: /usr/src/u-boot-master/drivers/ddr/marvell/a38x/mv_ddr4_training_calibration.c:757:
> undefined reference to `__aeabi_i2d'
> ld.bfd: /usr/src/u-boot-master/drivers/ddr/marvell/a38x/mv_ddr4_training_calibration.c:757:
> undefined reference to `__aeabi_dadd'
> ld.bfd: /usr/src/u-boot-master/drivers/ddr/marvell/a38x/mv_ddr4_training_calibration.c:757:
> undefined reference to `__aeabi_dcmpgt'
> ld.bfd: /usr/src/u-boot-master/drivers/ddr/marvell/a38x/mv_ddr4_training_calibration.c:758:
> undefined reference to `__aeabi_dsub'
> ld.bfd: /usr/src/u-boot-master/drivers/ddr/marvell/a38x/mv_ddr4_training_calibration.c:758:
> undefined reference to `__aeabi_d2uiz'
> ld.bfd: /usr/src/u-boot-master/drivers/ddr/marvell/a38x/mv_ddr4_training_calibration.c:770:
> undefined reference to `__aeabi_i2d'
> ld.bfd: /usr/src/u-boot-master/drivers/ddr/marvell/a38x/mv_ddr4_training_calibration.c:770:
> undefined reference to `__aeabi_dadd'
> ld.bfd: /usr/src/u-boot-master/drivers/ddr/marvell/a38x/mv_ddr4_training_calibration.c:770:
> undefined reference to `__aeabi_d2uiz'
> ld.bfd: drivers/ddr/marvell/a38x/mv_ddr4_training_calibration.o: in
> function `mv_ddr4_tap_tuning':
> /usr/src/u-boot-master/drivers/ddr/marvell/a38x/mv_ddr4_training_calibration.c:1124:
> undefined reference to `__aeabi_ui2d'
> ld.bfd: /usr/src/u-boot-master/drivers/ddr/marvell/a38x/mv_ddr4_training_calibration.c:1124:
> undefined reference to `__aeabi_dmul'
> ld.bfd: /usr/src/u-boot-master/drivers/ddr/marvell/a38x/mv_ddr4_training_calibration.c:1124:
> undefined reference to `__aeabi_dsub'
> ld.bfd: /usr/src/u-boot-master/drivers/ddr/marvell/a38x/mv_ddr4_training_calibration.c:1124:
> undefined reference to `__aeabi_ddiv'
> ld.bfd: /usr/src/u-boot-master/drivers/ddr/marvell/a38x/mv_ddr4_training_calibration.c:1124:
> undefined reference to `__aeabi_d2uiz'
> make[1]: *** [scripts/Makefile.spl:527: spl/u-boot-spl] Error 1
> <END ERRORS BUILD LOG >
> 
> And the config option that's relevant here is
> CONFIG_USE_PRIVATE_LIBGCC (default is Y) which enabled the usage of
> arch/arm/lib/lib.a, and caused the build errors.
> 
> # grep GCC .config
> CONFIG_CC_IS_GCC=y
> CONFIG_GCC_VERSION=100201
> CONFIG_HAVE_PRIVATE_LIBGCC=y
> CONFIG_USE_PRIVATE_LIBGCC=y
> 
> When I unset CONFIG_USE_PRIVATE_LIBGCC, the GGC library used is
> /usr/lib/gcc/arm-linux-gnueabi/10 and everything built.
> 
> # grep CONFIG_USE_PRIVATE_LIBGCC .config
> # CONFIG_USE_PRIVATE_LIBGCC is not set
> 
> <BEGIN GOOD BUILD LOG>
>    rm -f spl/common/spl/built-in.o; ar cDPrsT
> spl/common/spl/built-in.o spl/common/spl/spl.o
> spl/common/spl/spl_bootrom.o spl/common/spl/spl_spi.o
>   ( cd spl && ld.bfd  -T u-boot-spl.lds --gc-sections -Bstatic
> --gc-sections  --no-dynamic-linker --build-id=none -Ttext 0x40000030
> arch/arm/cpu/armv7/start.o --whole-archive
> arch/arm/mach-mvebu/built-in.o arch/arm/cpu/armv7/built-in.o
> arch/arm/cpu/built-in.o arch/arm/lib/built-in.o
> board/thecus/n2350/built-in.o common/spl/built-in.o
> common/init/built-in.o boot/built-in.o common/built-in.o
> cmd/built-in.o env/built-in.o lib/built-in.o disk/built-in.o
> drivers/built-in.o dts/built-in.o fs/built-in.o  --no-whole-archive
> arch/arm/lib/eabi_compat.o -L /usr/lib/gcc/arm-linux-gnueabi/10 -lgcc
> -Map u-boot-spl.map -o u-boot-spl )
> ld.bfd: warning:
> /usr/lib/gcc/arm-linux-gnueabi/10/libgcc.a(_udivmoddi4.o) uses 4-byte
> wchar_t yet the output is to use 2-byte wchar_t; use of wchar_t values
> across objects may fail
>   objcopy -j .text -j .secure_text -j .secure_data -j .rodata -j .hash
> -j .data -j .got -j .got.plt -j __u_boot_list -j .rel.dyn -j
> .binman_sym_table -j .text_rest -j .dtb.init.rodata -j .efi_runtime -j
> .efi_runtime_rel  -O binary  spl/u-boot-spl spl/u-boot-spl-nodtb.bin
>   objdump -t spl/u-boot-spl > spl/u-boot-spl.sym
>   cat spl/u-boot-spl-nodtb.bin spl/u-boot-spl-pad.bin
> spl/u-boot-spl.dtb > spl/u-boot-spl-dtb.bin
>   cp spl/u-boot-spl-dtb.bin spl/u-boot-spl.bin
>   ./tools/mkimage -n ./arch/arm/mach-mvebu/kwbimage.cfg -T kwbimage -a
> 0x00800000 -e 0x00800000  -d u-boot.bin u-boot-with-spl.kwb >/dev/null
>  && cat /dev/null
>   ./scripts/check-of.sh .config ./scripts/of_allowlist.txt
> make: Leaving directory '/usr/src/u-boot-master'
> + /bin/ls -lh u-boot-with-spl.kwb
> -rw-r--r-- 1 root root 581K Jan 14 13:12 u-boot-with-spl.kwb
> <END LOG>
> 
> I can also send you the whole log if you want. I'm preparing the
> Thecus N2350 patch and will send it within a few days.
> 
> Thanks,
> Tony