Hi Stefano, On 12.11.2012 14:02, Stefano Babic wrote: > On 12/11/2012 12:35, Andreas Bießmann wrote:
<snip> >>> +Function that a board must implement >>> +------------------------------------ >>> + >>> +void spl_board_prepare_for_linux(void) : optional >>> + Called from SPL before starting the kernel >>> + >>> +spl_start_uboot() : required >>> + Returns "0" if SPL starts the kernel, "1" if U-Boot >>> + must be started. >> >> In which way interact the CONFIG_SPL_OS_BOOT_KEY with the >> spl_start_uboot()? Is both required, can one use one or the other? > > Really checking the implementation, it should be better to remove > CONFIG_SPL_OS_BOOT_KEY. There is not a weak function for > spl_start_uboot(), and I think it is better so. But > CONFIG_SPL_OS_BOOT_KEY is used only inside spl_start_uboot() in the > board's implementation. IMHO it will be better to use a local define for > the GPIOs inside board files, and drop CONFIG_SPL_OS_BOOT_KEY (in > another patch, I mean). sounds good to me. >>> +img : "atags" or "fdt" >>> +kernel_addr : kernel is loaded as part of the boot process, but it >>> is not started. >>> + This is the address where a kernel image is stored. >> -------------------------------------------------------------^ >> persistently? >> This is the place in mass storage, right? > > No, but it could be (for NOR flash, for example). It is the address > where a uImage can be found. It could be in RAM after loading it with > tftp, or in a NOR flash. > > In any case, the spl command does not call itself utilities to copy the > kernel from mass storage - such as "nand read" or "fatload", for example. Ok, thats what I thought. But on first read of this README it was not clear to me which address I should write there. The step by step example should have some 'nand read' in it to clarify. >>> +init_addr : optional for atags - the address where the parameters area is >>> generated into RAM >> how about the initrd_addr mentioned above? > > What is not clear ? init_addr is the destination address, where spl puts > its result. Is it not clear from the description ? Well, the usage() for spl does not have a 'init_addr' but an 'initrd_addr'. Also your example line states: ---8<--- Usage: spl export <img=atags|fdt> [kernel_addr] [initrd_addr] [fdt_addr if <img> = fdt] - export a kernel parameter image initrd_img can be set to "-" if fdt_addr without initrd img isused --->8--- So for me it is not clear where the 'init_addr' come from. BTW: I find your detailed description way better than current usage() of spl command. Would IMHO be useful to add it there in another patch. another BTW: is there a typo in usage() for spl cmd? One line states 'initrd_addr' but some later it says 'initrd_img'. And last: the spl puts its result at a self gained position. The position is defined at compile time or when generating the uImage but not at command line for 'spl export' (see spl_export(): gd->bd->bi_boot_params vs. images.ft_addr). Best regards Andreas Bießmann _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot