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authorAlexey Brodkin <Alexey.Brodkin@synopsys.com>2016-03-28 14:36:38 +0300
committerVineet Gupta <vgupta@synopsys.com>2016-04-07 14:59:09 +0530
commite5e0a65cd20a7a892a87e6bd73bdc3d83726d725 (patch)
tree52b6bbcef2d992c6127ab156ff59567dfae780f9 /arch/arc
parent732dc97baec006c118bf49d52dd1c0b91b388497 (diff)
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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: linux-snps-arc@lists.infradead.org Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Diffstat (limited to 'arch/arc')
-rw-r--r--arch/arc/include/asm/fb.h19
1 files changed, 19 insertions, 0 deletions
diff --git a/arch/arc/include/asm/fb.h b/arch/arc/include/asm/fb.h
new file mode 100644
index 000000000000..bd3f68c9ddfc
--- /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_ */