> > IIRC, a similar buffer handling (via vmalloc) is used in video> > drivers. I suppose they don't work as well, right? Well, our FB driver is aware of the problem. I can't say much aboutother ones... > > DRM driver uses __vmalloc() with PAGE_KERNEL_NOCACHE, but it's only> > for PPC32 non-coherent. Hm. PPC with non-coherent cache? /* * Only on coherent architectures, we can mmap the status and the control records * for effcient data transfer. On others, we have to use HWSYNC ioctl... */#if defined(CONFIG_X86) || defined(CONFIG_PPC) || defined(CONFIG_ALPHA) ^^^^^^^^^^/* * mmap status record */static struct page * snd_pcm_mmap_status_nopage(struct vm_area_struct *area, unsigned long address, int *type) > x86 does it also, via its PAGE_AGP definition.> > There are not that many platforms that define PAGE_KERNEL_NOCACHE though,> so this gets a bit messy.. Oh, bloody hell, I haven't realised that! > Yeah, that's not sexy, but maybe the only working case right now> > (better with arch-specific ifdefs). The question is what ifdefs to use ;-) Because the cached/uncacheddecision must be consistent between snd_pcm_default_mmap() and bufferallocation... What a mess! ;-) Paweł _______________________________________________Alsa-devel mailing listAlsa-devel@xxxxxxxxxxxxxxxxxxxx://mailman.alsa-project.org/mailman/listinfo/alsa-devel
