Hi Jan, On Thu, Oct 6, 2016 at 3:45 PM, Jan Remmet <J.Remmet@xxxxxxxxx> wrote: > On Thu, Oct 06, 2016 at 11:08:07AM +0200, Yegor Yefremov wrote: >> I've submitted a patch [1] to support our Baltos systems back in the >> May. There was an issue with dynamically detecting RAM size as the >> systems can have either 256MB or 512MB modules. >> >> So far u-boot was able to detect the RAM size dynamically. In order to >> do so it uses following code in arch/arm/cpu/armv7/am33xx/emif4.c: >> >> int dram_init(void) >> { >> >> #ifndef CONFIG_SKIP_LOWLEVEL_INIT >> sdram_init(); >> #endif >> >> /* dram_init must store complete ramsize in gd->ram_size */ >> gd->ram_size = get_ram_size( >> (void *)CONFIG_SYS_SDRAM_BASE, >> CONFIG_MAX_RAM_BANK_SIZE); >> return 0; >> } >> >> void dram_init_banksize(void) >> { >> gd->bd->bi_dram[0].start = CONFIG_SYS_SDRAM_BASE; >> gd->bd->bi_dram[0].size = gd->ram_size; >> } >> >> This peace of code will be excuted in u-boot.img (not in MLO). >> >> In Barebox we have get_ram_size(), that provides real RAM size and >> am335x_sdram_size(), that returns RAM controller settings. So far DDR >> controler will be configured for 512MB regardless of the module. Hence >> the return value from am335x_sdram_size() cannot be used for crating >> ram0 node. > On our am335x boards we use MLOs with individual RAM timings and EMIF config > values. So am335x_sdram_size works fine in barebox.bin. > Maybe get_ram_size works if the timing settings are equal? I've solved the problem the way Sascha proposed earlier (see the third version of my patch sent today). In MLO I setup memory controller to 512MB, then I check the real amount via get_ram_size() and if I have 256MB I just reinitialize the memory controller with values for 256Mb i.e. rows 14 instead of 15. With this done one can use am335x_sdram_size() in other parts of berebox. Thanks for the feedback. Yegor _______________________________________________ barebox mailing list barebox@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/barebox