> Would it be possible to tell the case/path, where L_PTE_CACHEABLE/L_PTE_BUFFERABLE is set with VM_IO/VM_RESERVED ? Currently, display driver maps the video buffers to userspace with VM_RESERVED flag and pgprot_writecombine(). We are considering changing pgprot_writecombine() to pgprot_noncached() to eliminate the need of all cache maintenance overheads for video buffers. Regarding Felipe's comment: > L_PTE_BUFFERABLE is obsolete, isn't it? L_PTE_MT_BUFFERABLE should be used instead. I was working on 2.6.27.10, and agree that this needs to be updated for newer kernels. Regards, Sripal -----Original Message----- From: Hiroshi DOYU [mailto:Hiroshi.DOYU@xxxxxxxxx] Sent: Thursday, June 11, 2009 2:16 AM To: Ramirez Luna, Omar Cc: felipe.contreras@xxxxxxxxx; ameya.palande@xxxxxxxxx; Menon, Nishanth; Bagadia, Sripal; Kanigeri, Hari; linux-omap@xxxxxxxxxxxxxxx Subject: Re: [RFC][PATCH] DSPBRIDGE: Video Playback Cache Optimization From: Hiroshi DOYU <Hiroshi.DOYU@xxxxxxxxx> Subject: Re: [RFC][PATCH] DSPBRIDGE: Video Playback Cache Optimization Date: Wed, 10 Jun 2009 10:25:39 +0300 (EEST) > From: "ext Ramirez Luna, Omar" <omar.ramirez@xxxxxx> > Subject: RE: [RFC][PATCH] DSPBRIDGE: Video Playback Cache Optimization > Date: Wed, 10 Jun 2009 01:18:29 +0200 > > > Hi, > > > > [sending as plain text to l-o] > > > > Could you please comment on this patch. > > > > From: Sripal Bagadia <bagadia@xxxxxx> > > Date: Tue, 9 Jun 2009 16:05:09 -0500 > > Subject: [PATCH] DSPBRIDGE: Video Playback Cache Optimization > > > > Avoid get_user_pages cache flush overheads for uncached & reserved > > buffers (e.g. display & camera buffers). > > Would it be possible to tell the case/path, where no > L_PTE_CACHEABLE/L_PTE_BUFFERABLE is set with VM_IO/VM_RESERVED ? To be correct, "where L_PTE_CACHEABLE/L_PTE_BUFFERABLE is set with VM_IO/VM_RESERVED" > > > > Signed-off-by: Sripal Bagadia <bagadia@xxxxxx> > > --- > > drivers/dsp/bridge/wmd/tiomap3430.c | 4 +++- > > 1 files changed, 3 insertions(+), 1 deletions(-) > > > > diff --git a/drivers/dsp/bridge/wmd/tiomap3430.c > > b/drivers/dsp/bridge/wmd/tiomap3430.c > > index 7a9603d..a2f32e8 100644 > > --- a/drivers/dsp/bridge/wmd/tiomap3430.c > > +++ b/drivers/dsp/bridge/wmd/tiomap3430.c > > @@ -1461,7 +1461,9 @@ static DSP_STATUS WMD_BRD_MemMap(struct > > WMD_DEV_CONTEXT *hDevContext, > > goto func_cont; > > } > > > > - if (vma->vm_flags & VM_IO) { > > + if ((vma->vm_flags & VM_IO) | ((vma->vm_flags & VM_RESERVED) > > +&& > > + (~pgprot_val(vma->vm_page_prot) & L_PTE_CACHEABLE) > > +&& > > + (~pgprot_val(vma->vm_page_prot) & > > +L_PTE_BUFFERABLE))) { > > numUsrPgs = ulNumBytes / PG_SIZE_4K; > > mpuAddr = ulMpuAddr; > > DBG_Trace(DBG_LEVEL4, "WMD_BRD_MemMap:numOfActualTabEntries=%d," > > -- > > 1.6.2.4 > > -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
