On Wed, 2008-05-07 at 11:49 +0200, Matthias Welwarsky wrote: > steven.zhang wrote: > > On Wed, 2008-05-07 at 10:36 +0200, Vladimir Pantelic wrote: > > > > > steven.zhang wrote: > > > > > > > So many thanks!Vladimir. > > > > But why 720*480 succeeded?Its size is 2488320 byte, which exceeds 2M > > > > already. > > > > I have checked the CONSISTENT_DMA_SIZE of my arch.Its value is 14M, that > > > > should be enough. > > > > > > > yes, I saw that after sending the mail > > > > > > > > > > any other suggestion? > > > > > > > well, the kernel tries to find such a big contiguous piece of memory, > > > maybe the > > > memory is already too fragmented at that time? > > > > > > > > Yes, I think, we should not allocate frame buffer memory dynamic.Map a fix > > memory area before kernel start? > > > > I'm afraid so, yes. I've been trying to use dma_alloc_coherent() > dynamically, but it's not very flexible. Especially if you use it a > lot on memory blocks not sized 2^n, it's causing a lot of > fragmentation by itself. It's implemented using get_free_pages(), but > this is only allocating sized 2^n blocks of memory. So > dma_alloc_coherent() allocates the next bigger 2^n block and then > free's the excess pages one by one. That isn't really helping with > keeping the memory pool in shape. > And your suggestion? Is there a better API to allocation the DMA memory?Thanks.
> -- > Matthias Welwarsky > Project Manager Software > Germany > > > > ______________________________________________________________________ > This email and any files transmitted with it are confidential and are > intended solely for the use of the individual or entity to which they > are addressed. Access to this e-mail by anyone else is unauthorised. > If you are not the intended recipient, any disclosure, copying, > distribution or any action taken or omitted to be taken in reliance on > it, is prohibited. E-mail messages are not necessarily secure. Archos > does not accept responsibility for any changes made to this message > after it was sent. > > _______________________________________________ Davinci-linux-open-source mailing list [email protected] http://linux.davincidsp.com/mailman/listinfo/davinci-linux-open-source
