Hi Rajdeep, On Wed, 10 Jul 2013 15:04:12 +0530, Rajdeep Vaghasia <[email protected]> wrote:
> Waiting for a reply. Well, maybe if you had not e-mailed your 8:32 AM answer to me but to the list... :) Here it is, with my comments. > On Tue, Jul 9, 2013 at 5:31 PM, Albert ARIBAUD > <[email protected]>wrote: > > > Hi Rajdeep, > > > > On Tue, 9 Jul 2013 16:12:14 +0530, Rajdeep Vaghasia > > <[email protected]> wrote: > > > > > Hi > > > I am working on one board with an arm11 based cpu, NOR flash and DDR2 > > SDRAM. > > > When I compile u-boot source code, I get u-boot.bin image generated. > > > This image has primary(second stage) and secondary(third stage) > > bootloader > > > combined. > > > > > > I have following queries: > > > 1) The question that still eats me everyday is, How can I compile > > > primary(Master) boot loader and secondary boot loader separately? > > > 2) I want to Flash only initial 4kb of code (Master boot loader or second > > > stage). The remaining code I want to keep at another partition in the > > > Flash. How can I achieve this? > > > 3) Is there any separate code available for Master boot loader, which > > > copies the third stage bootloader to SDRAM and then transfers control to > > > that third stage boot loader(u-boot)? > > > > > > I am unable to find a way to do this. > > > > > > Can anyone help me please? > > > > Since you do not indicate exactly which target you're building, I'll > > assume it is one with SPL (what you describe as master or second stage, > > with third stage being u-boot itself). > > > > I don't know of a way to build SPL alone. > > > > As for building separate U-Boot and SPL, you'll find them in ELF format > > in file ./u-boot and ./spl/u-boot-spl. You can then use > > $(CROSS_COMPILE)objcopy to convert from ELF to .bin. > > > > Note that your target may need a specific format different from the > > pure binary that objcopy can produce. > > > > Can you tell us more about your target? > > > > Amicalement, > > -- > > Albert. > > > > Sorry, My target board is not with SPL. Then your question does not make sense, since a target without SPL has no "second" and "third" stage, only a single standalone U-Boot stage. > According to my understanding, SPL is required when we want to use NAND or > oneNAND flash. And even in that case, the image generated, is combined of > u-boot.bin+nand_driver. This is quite reductive and partly wrong. SPL is required when you cannot directly boot into U-boot, one of the cases being when you boot from NAND as it usually only allows very small binaries; but NAND is far from the only case where SPL is needed or useful. Also, as I said, the image generated in the SPL case is not "u-boot + NAND driver", it is "complete SPL + complete U-Boot" (although you can have them separate as I explained), and the "complete SPL" part is not itself an "U-Boot plus NAND driver". > I am using NOR flash. Ok. > Actually, I am building firmware upgrade procedure. > For that I need 3 partitions for u-boot. > One with master u-boot. > Other two with u-boot-1 and u-boot-2. (One contains current working u-boot, > whereas another is with upgraded u-boot code). > For that I need one Master uboot which contains code that initializes the > SDRAM, choses one of the 2 secondary u-boot with the help of an environment > variable (Or fixed jump to the start address of u-boot-1 or u-boot-2) and > then copies u-boot(Secondary boot loader) to SDRAM and executes it from > there. Ok, so "secondary" is a concept specific to your design. No wonder I could not understand it properly until you explained. > These steps of initializing SDRAM and copying of u-boot code there, are > already implemented in u-boot code. I just want to separate it from the > main source code and want to generate binary of that much code only. > > Is there any way to achieve this? Several; and then there is an infinity of other possible approaches, depending, not on *what* you want to do, but on *why* you want to do it. Can you give more details on why your firmware upgrade procedure needs to boot two different U-Boots ? > or > Is there any resource of information available which can help me to > understand this? The source code and the Denx website, at this point; once you explain the goal you are trying to reach, people on the list might point you to more specific resources. > Rajdeep. Amicalement, -- Albert. _______________________________________________ U-Boot mailing list [email protected] http://lists.denx.de/mailman/listinfo/u-boot
