From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:45858) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1W02ie-0006x2-NV for qemu-devel@nongnu.org; Mon, 06 Jan 2014 00:27:25 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1W02ia-00019l-4C for qemu-devel@nongnu.org; Mon, 06 Jan 2014 00:27:20 -0500 Received: from [222.73.24.84] (port=63532 helo=song.cn.fujitsu.com) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1W02iZ-00018x-Po for qemu-devel@nongnu.org; Mon, 06 Jan 2014 00:27:16 -0500 Message-ID: <52CA3E19.90900@cn.fujitsu.com> Date: Mon, 06 Jan 2014 13:24:41 +0800 From: Li Guang MIME-Version: 1.0 References: <1388640940-12782-1-git-send-email-lig.fnst@cn.fujitsu.com> <52C52170.1040904@redhat.com> <52C5588B.30804@redhat.com> <52C9FE6B.4050408@cn.fujitsu.com> <52CA2922.1010308@cn.fujitsu.com> <52CA2FA1.6080002@cn.fujitsu.com> <52CA368B.2080506@cn.fujitsu.com> In-Reply-To: <52CA368B.2080506@cn.fujitsu.com> Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=ISO-8859-1; format=flowed Subject: Re: [Qemu-devel] [PATCH] hw/misc/blob-loader: add a generic blob loader List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Peter Crosthwaite Cc: Paolo Bonzini , "qemu-devel@nongnu.org Developers" , Peter Maydell Li Guang wrote: > Peter Crosthwaite wrote: >> On Mon, Jan 6, 2014 at 2:22 PM, Li Guang >> wrote: >>> Peter Crosthwaite wrote: >>>> On Mon, Jan 6, 2014 at 1:55 PM, Li Guang >>>> wrote: >>>> >>>>> Li Guang wrote: >>>>> >>>>>> Paolo Bonzini wrote: >>>>>> >>>>>>> Il 02/01/2014 11:51, Peter Crosthwaite ha scritto: >>>>>>> >>>>>>>>>> No, please use "realize" and avoid init. This way you can >>>>>>>>>> use an >>>>>>>>>> Error* >>>>>>>>>> to report the error. >>>>>>>>>> >>>>>>>>>> Also, the actual load_image_targphys call probably should be >>>>>>>>>> done in >>>>>>>>>> a >>>>>>>>>> reset handler, not at realize time. >>>>>>>>>> >>>>>>>>>> >>>>>>>> Ok I think that settles it. The actual blobbing needs to happen at >>>>>>>> reset time. Perhaps the correct approach is to do as much as >>>>>>>> possible >>>>>>>> (file-path / address sanitsation etc) at realize time, then >>>>>>>> only the >>>>>>>> actual blob load happens at reset. Going on what Paolo said, I >>>>>>>> think >>>>>>>> for this device ::init is actually a nop. >>>>>>>> >>>>>>> Yeah, also because init is in fact a legacy interface to realize. >>>>>>> >>>>>>> Paolo >>>>>>> >>>>>>> >>>>>> Ok, thanks! >>>>>> >>>>>> >>>>>> >>>>> Sorry, seems load blob at reset handler can't do the right job, >>>>> while the same action can play very well at init or realize. >>>>> >>>> What's the exact problem with the reset idea? >>>> >>>> >>>> >>> code snippet: >>> static void blob_loader_reset(DeviceState *dev) >>> { >>> BlobLoaderState *s = BLOB_LOADER(dev); >>> >>> if (load_image_targphys(s->file, s->hwaddr, MAX_BLOB_SIZE)< 0) { >>> error_report("can't load %s\n", s->file); >>> exit(1); >>> } >>> } >>> >>> if it is device reset handler, no result, >>> kernel doesn't find and parse blob, >>> if it is called at device realize phase, >>> it works. >>> >> Need to figure out why I think. There's no fundamental problem here >> AFAIK. It must be a bug somewhere. >> >>> Thanks! >>> >>> >>>>> any suggestion to figure out this problem? >> Run QEMU in GDB and break on your new reset function to see if it is >> ever called. If not have a look into QOM/qdev to see how resets work >> and how that plays with -device args. If yes, have a look into >> load_image_targphys and see why that's not working. >> >> > > reset handler definitely be called, and > load_image_targphys has no problem, > I guess it may be impacted by other RAM related codes, > just can't figure out it quickly. > Ok, I found the problem finally, load_image_targphys depends on rom_reset to take effect, if it's located at reset handler, rom_reset is called before it, it surely failed to do the right job. so, I have to write my own code to load blob into RAM. Thanks!