| Message ID | 1459164999-11850-5-git-send-email-abrodkin@synopsys.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi Vineet, > From: Alexey Brodkin [abrodkin@synopsys.com] > Sent: Monday, March 28, 2016 2:36 PM > To: dri-devel@lists.freedesktop.org > Cc: linux-kernel@vger.kernel.org; Alexey Brodkin; Vineet Gupta; linux-snps-arc@lists.infradead.org > Subject: [PATCH 4/5 v5] arc: Add our own implementation of fb_pgprotect() > > During mmaping of frame-buffer pages to user-space > fb_protect() is called to set proper page settings. > > In case of ARC we need to mark pages that are mmaped to > user as uncached because of 2 reasons: > * Huge amount of data if passing through data cache will > thrash cache a lot making cache almost useless for other > less traffic hungry processes. > * Data written by user in FB will be immediately available for > hardware (such as PGU etc) without requirements to flush data > cache regularly. > > Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com> > Cc: Vineet Gupta <vgupta@synopsys.com> > Cc: linux-snps-arc@lists.infradead.org Could you please pick up this patch in your tree so in DRM-related series won't be external dependencies any longer? -Alexey
diff --git a/arch/arc/include/asm/fb.h b/arch/arc/include/asm/fb.h new file mode 100644 index 0000000..bd3f68c --- /dev/null +++ b/arch/arc/include/asm/fb.h @@ -0,0 +1,19 @@ +#ifndef _ASM_FB_H_ +#define _ASM_FB_H_ + +#include <linux/fb.h> +#include <linux/fs.h> +#include <asm/page.h> + +static inline void fb_pgprotect(struct file *file, struct vm_area_struct *vma, + unsigned long off) +{ + vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); +} + +static inline int fb_is_primary_device(struct fb_info *info) +{ + return 0; +} + +#endif /* _ASM_FB_H_ */
During mmaping of frame-buffer pages to user-space fb_protect() is called to set proper page settings. In case of ARC we need to mark pages that are mmaped to user as uncached because of 2 reasons: * Huge amount of data if passing through data cache will thrash cache a lot making cache almost useless for other less traffic hungry processes. * Data written by user in FB will be immediately available for hardware (such as PGU etc) without requirements to flush data cache regularly. Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: linux-snps-arc@lists.infradead.org --- No changes v4 -> v5. Changes v3 -> v4: * This change was introduced only in v4. arch/arc/include/asm/fb.h | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) create mode 100644 arch/arc/include/asm/fb.h