![Alexey Brodkin](/assets/img/avatar_default.png)
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>
20 lines
372 B
C
20 lines
372 B
C
#ifndef _ASM_FB_H_
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#define _ASM_FB_H_
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#include <linux/fb.h>
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#include <linux/fs.h>
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#include <asm/page.h>
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static inline void fb_pgprotect(struct file *file, struct vm_area_struct *vma,
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unsigned long off)
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{
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vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
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}
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static inline int fb_is_primary_device(struct fb_info *info)
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{
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return 0;
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}
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#endif /* _ASM_FB_H_ */
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