Increase in BIOS+firmware size increase with latest LiteX revision

[mithro]

As of 3350d33 (see timvideos/litex-buildenv#314) - the LiteX-BuildEnv is showing a lot of failures see https://travis-ci.com/timvideos/litex-buildenv/builds/146976853

This seems to be a result of BIOS / firmware seeming to use a lot more SRAM. This seems to affect all of lm32, mor1kx and vexriscv configurations;

lm32 example

cp /home/travis/build/timvideos/litex-buildenv/third_party/litex/litex/soc/software/bios/boot-helper-lm32.S boot-helper-lm32.S
 CC       boot-helper-lm32.o
 LD       firmware.elf
lm32-elf-ld: firmware.elf section `.bss' will not fit in region `sram'
lm32-elf-ld: region `sram' overflowed by 10136 bytes

vexriscv example

https://travis-ci.com/timvideos/litex-buildenv/jobs/282427202

 CC       /home/travis/build/timvideos/litex-buildenv/build/arty_base_vexriscv/software/include/../..//software/firmware/version_data.o
 CC       /home/travis/build/timvideos/litex-buildenv/build/arty_base_vexriscv/software/include/../..//software/firmware/hdmi_in1.o
cp /home/travis/build/timvideos/litex-buildenv/third_party/litex/litex/soc/software/bios/boot-helper-vexriscv.S boot-helper-vexriscv.S
 CC       boot-helper-vexriscv.o
 LD       firmware.elf
riscv32-unknown-elf-ld: firmware.elf section `.bss' will not fit in region `sram'
riscv32-unknown-elf-ld: region `sram' overflowed by 10136 bytes
/home/travis/build/timvideos/litex-buildenv/firmware/Makefile:93: recipe for target 'firmware.elf' failed
make[1]: *** [firmware.elf] Error 1

mor1kx example

https://travis-ci.com/timvideos/litex-buildenv/jobs/282427196

 CC       boot.o
 LD       bios.elf
or1k-elf-ld: bios.elf section `.text' will not fit in region `rom'
or1k-elf-ld: region `rom' overflowed by 6424 bytes
/home/travis/build/timvideos/litex-buildenv/third_party/litex/litex/soc/software/bios/Makefile:27: recipe for target 'bios.elf' failed
make[1]: *** [bios.elf] Error 1

[mithro]

The issue seems to actually be 83a7225 when combined with 7a05353 that causes this problem. The code in LiteX-BuildEnv does the following;

        if 'integrated_rom_size' not in kwargs:
            kwargs['integrated_rom_size']=0x8000
        if 'integrated_sram_size' not in kwargs:
            kwargs['integrated_sram_size']=0x8000

[enjoy-digital]

@mithro, @mateusz-holenko: is it now resolved in litex-buildenv?

[mateusz-holenko]

I prepared a PR that fixes buildenv's platforms after bumping to the current LiteX: timvideos/litex-buildenv#348.

It reworks the way LiteX-BuildEnv configures integrated rom/sram size and it should solve the issue.

[enjoy-digital]

From the recent discussions, it seems to be related to the way the arguments are handled in litex-buildenv, so we can probably close this.