diff options
| author |   Alexey Brodkin <Alexey.Brodkin@synopsys.com> | 2016-03-28 14:36:38 +0300 |
|---|---|---|
| committer |   Vineet Gupta <vgupta@synopsys.com> | 2016-04-07 14:59:09 +0530 |
| commit | e5e0a65cd20a7a892a87e6bd73bdc3d83726d725 (patch) | |
| tree | 52b6bbcef2d992c6127ab156ff59567dfae780f9 /arch | |
| parent | ARC: Don't source drivers/pci/pcie/Kconfig ourselves (diff) | |
| download | linux-dev-e5e0a65cd20a7a892a87e6bd73bdc3d83726d725.tar.xz linux-dev-e5e0a65cd20a7a892a87e6bd73bdc3d83726d725.zip | |
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')
| -rw-r--r-- | arch/arc/include/asm/fb.h | 19 |
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_ */ |