From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ian Campbell Date: Fri, 27 Feb 2015 16:39:45 +0000 Subject: [U-Boot] [RFC] sunxi: Support uploading 'boot.scr' to RAM over USB OTG in FEL mode In-Reply-To: <1424746131-11740-1-git-send-email-siarhei.siamashka@gmail.com> References: <1424746131-11740-1-git-send-email-siarhei.siamashka@gmail.com> Message-ID: <1425055185.14641.249.camel@hellion.org.uk> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On Tue, 2015-02-24 at 04:48 +0200, Siarhei Siamashka wrote: > In order to fully support booting the whole system over USB OTG > without relying on anything else (MMC, SATA, USB sticks, ...), it > is possible to upload the 'boot.scr' file to DRAM using the 'fel' > tool. But U-Boot still needs to be able to pick it up there before > checking any other boot media. > > Signed-off-by: Siarhei Siamashka > --- > > The patch might be not the best way to implement this. But it would > be great if U-Boot had out of the box support for: > http://linux-sunxi.org/index.php?title=FEL/USBBoot&oldid=13134#Boot_the_whole_system_over_USB_.28u-boot_.2B_kernel_.2B_initramfs.29 > > One of the bad things about this patch is that the "scriptaddr" > variable needs to be hardcoded and protected agaist modifications > (if this address is to be used from the SPL). Perhaps use a separate dedicated/hardcoded address for the FEL boot script to avoid adding unusual semantics to $scriptaddr (which might surprise users not using fel)? If the FEL address has to be 0x43100000 for compatibility with existing instructions/tools that might mean moving the current scriptaddr elsewhere. I think we can live with that. > Also I'm not sure how this all could fit into the > "config_distro_bootcmd.h" model, so I even have not tried > that yet. Just at a quick glance, based on the PXE entry something like: #define BOOTENV_DEV_FEL(devtypeu, devtypel, instance) \ "bootcmd_fel=source ...\0" i.e. all the magic params are irrelevant in this case. Perhaps "bootcmd_"#devtypel"=...\0" but I don't think that's needed in this instance. BOOTENV_DEV_PXE doesn't bother at least. Then in BOOT_TARGET_DEVICES include "func(FEL, fel, na)" Ian.