Of all the gin joints in all the towns in all the world, Carsey, Jaben had to walk into mine at 17:26:07 on Wednesday 05 March 2014 and say:
> A driver is able to do this, but whether your driver gets loaded and run is > a platform policy decision and may be different for your tablet. Can you elaborate? Where is the policy controlled from? I know that some UEFI firmware implementations have a setup menu option to enable/disable loading of option ROMs, but it's not clear to me if this applies only to BIOS option ROMs -- usually it affects whether or not the PXE ROM is loaded. And the setup menu on this tablet is very limited -- I'm pretty sure it didn't have any option to configure this. > If you go ahead with it, you may borrow some code from the shell's BCFG > command for BOOTXXXX variable manipulation. Oh I already know how to handle this with gBS->SetVariable(). (That's what got me into this mess in the first place.) -Bill > -Jaben > > -----Original Message----- > From: Bill Paul [mailto:wp...@windriver.com] > Sent: Wednesday, March 05, 2014 5:12 PM > To: edk2-devel@lists.sourceforge.net > Subject: [edk2] Question about firmware startup order of events > > You may recall that I mentioned that due to a mishap with some UEFI OS > loader code I was developing, I managed to brick my UEFI-based tablet by > setting an improperly formatted boot path variable as the default boot > path. > > Unfortunately unplugging the internal SSD drive didn't have any effect, and > I haven't been able to think of a way to directly re-whack the NVRAM, and > I don't have a way to hook my JTAG probe to it. I did think of one > potential way around the problem, but there's something I need to clarify > first. > > The tablet has wifi support, in the form of an Atheros mini-PCIe adapter > which is plugged into the main board. This adapter can be easily unplugged > and replaced. > > What I'm considering is using the EDK2 to cobble together a UEFI driver > with just enough code in it to erase the BootXXXX and BootOrder variables > and flashing it to some device which I can fit into this mini-PCIe slot, > in the hopes that I can get the firmware to run this code for me. > > But this will only work if the driver is loaded and executed before the > firmware gets to the boot device selection code. Conceptually it would > seem that this would be the case (I mean, you need to load the drivers for > devices before you can use them as boot paths, right?) but I'm not > positive if this so. > > Can anyone tell me if this idea has a chance of working? It costs me > nothing to tinker around with the EDK2, but it would cost me a little do > obtain a suitable PCIe device, so I want to check before I end up spending > money for nothing. > > -Bill > > -- > =========================================================================== > == -Bill Paul (510) 749-2329 | Senior Member of Technical Staff, > wp...@windriver.com | Master of Unix-Fu - Wind River Systems > ========================================================================== > === "I put a dollar in a change machine. Nothing changed." - George Carlin > ========================================================================== > === > > --------------------------------------------------------------------------- > --- Subversion Kills Productivity. Get off Subversion & Make the Move to > Perforce. With Perforce, you get hassle-free workflows. Merge that > actually works. Faster operations. Version large binaries. Built-in WAN > optimization and the freedom to use Git, Perforce or both. Make the move > to Perforce. > http://pubads.g.doubleclick.net/gampad/clk?id=122218951&iu=/4140/ostg.clkt > rk _______________________________________________ > edk2-devel mailing list > edk2-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/edk2-devel > > --------------------------------------------------------------------------- > --- Subversion Kills Productivity. Get off Subversion & Make the Move to > Perforce. With Perforce, you get hassle-free workflows. Merge that > actually works. Faster operations. Version large binaries. Built-in WAN > optimization and the freedom to use Git, Perforce or both. Make the move > to Perforce. > http://pubads.g.doubleclick.net/gampad/clk?id=122218951&iu=/4140/ostg.clktr > k _______________________________________________ > edk2-devel mailing list > edk2-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/edk2-devel -- ============================================================================= -Bill Paul (510) 749-2329 | Senior Member of Technical Staff, wp...@windriver.com | Master of Unix-Fu - Wind River Systems ============================================================================= "I put a dollar in a change machine. Nothing changed." - George Carlin ============================================================================= ------------------------------------------------------------------------------ Subversion Kills Productivity. Get off Subversion & Make the Move to Perforce. With Perforce, you get hassle-free workflows. Merge that actually works. Faster operations. Version large binaries. Built-in WAN optimization and the freedom to use Git, Perforce or both. Make the move to Perforce. http://pubads.g.doubleclick.net/gampad/clk?id=122218951&iu=/4140/ostg.clktrk _______________________________________________ edk2-devel mailing list edk2-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/edk2-devel
