On 10/18/2012 02:58 PM, Stephen Warren wrote: > On 10/18/2012 02:36 PM, Albert ARIBAUD wrote: >> Hi Stephen, >> >> On Wed, 17 Oct 2012 21:17:45 -0600, Stephen Warren >> <swar...@wwwdotorg.org> wrote: >> >>> On 10/17/2012 05:58 PM, Simon Glass wrote: >>>> Hi Stephen, >>>> >>>> On Tue, Oct 16, 2012 at 2:50 PM, Stephen Warren <swar...@wwwdotorg.org> >>>> wrote: >>>>> From: Stephen Warren <swar...@nvidia.com> >>>>> >>>>> When -ffunction-sections or -fdata-section are used, symbols are placed >>>>> into sections such as .data.eserial1_device and .bss.serial_current. >>>>> Update the linker script to explicitly include these. Without this >>>>> change (at least with my gcc-4.5.3 built using crosstool-ng), I see that >>>>> the sections do end up being included, but __bss_end__ gets set to the >>>>> same value as __bss_start. >>>>> >>>>> Signed-off-by: Stephen Warren <swar...@nvidia.com> >>>>> --- >>>>> This series fixes an SPL size overflow problem on Tegra. Tom Warren is >>>>> out on vacation until Oct 25th, so he certainly won't be able to review >>>>> this. Perhaps it could be applied directly to the ARM tree if enough >>>>> Tegra people ack the series? >>>>> >>>>> Note that this series is not enough to make Tegra support work; either >>>>> you must hack ./arch/arm/cpu/arm720t/tegra-common/spl.c to call >>>>> serial_initialize() right before serial_init() in preloader_console_init() >>>>> or wait for Allen Martin to rework Tegra's SPL support using the common >>>>> SPL code. >>>> >>>> Are you going to submit a patch to enable function-sections, or is >>>> that a separate discussion? >>> >>> For the SPL on Tegra, those flags were already on; this patch fixes a >>> bug rather than prepares for new functionality. >>> >>>>> diff --git a/arch/arm/cpu/u-boot.lds b/arch/arm/cpu/u-boot.lds >>> >>>>> - .u_boot_cmd : { *(.u_boot_cmd) } >>>>> + .u_boot_cmd : { *(.u_boot_cmd*) } >>>> >>>> I don't think this line is needed? >>>> >>> ... >>>>> - *(.dynsym) >>>>> + *(.dynsym*) >>>> >>>> Nor this one? >>> >>> Possibly. I changed all the section names to be future-proof. Perhaps a >>> more targeted patch is warranted. >> >> Has this been (at least build-)tested on all boards which have >> -ffunction-sections or -fdata-sections? > > Yes; those flags both appear to be turned on when building the SPL for > Tegra (although strangely, not when building the main U-Boot): > > xxx-gcc -M -g -Os -fno-common -ffixed-r8 -msoft-float -D__KERNEL__ > -ffunction-sections -fdata-sections -DCONFIG_SYS_TEXT_BASE=0x0010c000 > -DCONFIG_SPL_TEXT_BASE=0x00108000 -DCONFIG_SPL_BUILD > -I/home/swarren/shared/git_wa/u-boot/include -fno-builtin -ffreestanding > -nostdinc -isystem xxx -pipe -DCONFIG_ARM -D__ARM__ -marm > -mno-thumb-interwork -mabi=aapcs-linux -march=armv4 -mtune=arm7tdmi -MQ > xxx/spl/arch/arm/cpu/arm720t/interrupts.o interrupts.c > > xxx/spl/arch/arm/cpu/arm720t/.depend.interrupts
I tried to test this more widely. I found that only arch/arm/cpu/ixp/config.mk enables this on ARM, with the comment: > # -fdata-sections triggers "section .bss overlaps section .rel.dyn" linker > error > PLATFORM_RELFLAGS += -ffunction-sections > LDFLAGS_u-boot += --gc-sections Indeed, if I edit arch/arm/cpu/armv7/config.mk to enable both -ffunction-sections -fdata-sections, I do see that same section overlap error building for Tegra. Then, if I apply the .lds patch we're discussing, Tegra builds (and runs) OK with those linker flags enabled. So, this patch seems to fix two issues not just one - bonus:-) _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot