John, On Saturday 08 January 2011 12:16 PM, John Rigby wrote: > On Fri, Jan 7, 2011 at 11:33 PM, Aneesh V<ane...@ti.com> wrote: >> Hi John, >> >> On Tuesday 28 December 2010 06:17 AM, John Rigby wrote: >>> >>> Signed-off-by: John Rigby<john.ri...@linaro.org> >>> + >>> +void board_init_f(unsigned long bootflag) >>> +{ >>> + nand_boot(); >>> +} >>> + >> >> I see that you have added a call to nand_boot() in start.S too. >> Which is the intended one? >> If we jump to nand_boot() here bss will not be cleared, right? >> >> Also, I see potential issues in start.S that will prevent bss setup for >> PRELOADERs. I will correct these in my patch. >> >> Best regards, >> Aneesh >> > > The call to nand_boot in board_init_f makes sense for platforms where > the spl code does not need to be relocated because it has been loaded > into SRAM by a mask boot rom. The later nand_boot called from start.S > is for the traditional nand_spl case where you are typically running > in a 4K nand controller buffer so the code needs to be relocated to > dram after dram init. > > Of course my only testing has been on OMAP3 which fits the first case. > I'm not sure if the second case even matters. The arm7 platforms I > know about all have rom boot loaders and large enough SRAM to run the > spl u-boot in (OMAP[34]) or have boot headers that can be used to init > dram before loading a full u-boot into dram (i.mx5[13]). > > Also, I was thinking that BSS would not be used in PRELOADERs but of > the large SRAM case it certainly would be useful to have BSS. >
Agree. So, how about this? 1. Call relocate_code() in board_init_f() with destination address same as TEXT_BASE 2. start.S skips the relocation, clears the bss(this needs to be fixed) and calls board_init_r 3. Call nand_boot() in board_init_r This is what I am planning to do for OMAP4 preloader. > This is all new territory since previously all platforms using > nand_spl were of the small sram variety. > > John Thanks, Aneesh _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot