From mboxrd@z Thu Jan 1 00:00:00 1970 From: Julien Grall Subject: Re: XEN[ARM] Master not working on Allwinner A20 Date: Tue, 07 Jan 2014 14:44:53 +0000 Message-ID: <52CC12E5.1000202@linaro.org> References: <1387188577.20076.44.camel@kazak.uk.xensource.com> <1387199654.10247.30.camel@kazak.uk.xensource.com> <52B05913.2080300@linaro.org> <1389103098.12612.21.camel@kazak.uk.xensource.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: "karim.allah.ahmed@gmail.com" Cc: Anthony PERARD , peter , Ian Campbell , xen-devel@lists.xen.org List-Id: xen-devel@lists.xenproject.org On 01/07/2014 02:31 PM, karim.allah.ahmed@gmail.com wrote: > On Tue, Jan 7, 2014 at 1:58 PM, Ian Campbell wrote: >> On Sun, 2014-01-05 at 16:48 +0000, karim.allah.ahmed@gmail.com wrote: >> >>> If you still can't boot with any memory bigger than 128M, as a fast >>> workaround you can apply this patch. >> >> I wonder if it might be possible to work around this by more carefully >> selecting the load addresses for Xen+Linux+DTB+initrd, such that they >> are packed into the top end of RAM, leaving a larger contiguous chunk >> available at the beginning. e.g. if sizeof(Xen)=X and sizeof(Linux)=L >> and sizeof(DTB)=D (all rounded up to 2M boundary) then load things at: >> MEMMAX-X: Leave free for high relocation of hypervisor >> MEMMAX-X-L: Load Linux here >> MEMMAX-X-L-D: Load DTB here >> MEMMAX-X-L-D-X: Load initial Xen image here >> >> Ultimately this is because allocations need to be aligned to their size, >> so on a 1GB system there are only two possible 512MB allocations, if >> even one page is allocated in each half then it isn't possible to >> satisfy things. I don't think the core allocator gives us the option to >> do non-aligned allocations. > > What if we allocated the dom0 from the boot allocator instead (before > ditching it) ? If I remembered correctly, Anthony did this kind of modification for the first port of Xen on the Arndale. It's a too intrusive in the code. As I said previously, the best solution is having multiple bank support for dom0. It will take you less time to wrote a such patch. -- Julien Grall