Commit 8f8eaa1b authored by Thomas Zimmermann's avatar Thomas Zimmermann
Browse files

fbdev: Move framebuffer I/O helpers into <asm/fb.h> 



Implement framebuffer I/O helpers, such as fb_read*() and fb_write*(),
in the architecture's <asm/fb.h> header file or the generic one.

The common case has been the use of regular I/O functions, such as
__raw_readb() or memset_io(). A few architectures used plain system-
memory reads and writes. Sparc used helpers for its SBus.

The architectures that used special cases provide the same code in
their __raw_*() I/O helpers. So the patch replaces this code with the
__raw_*() functions and moves it to <asm-generic/fb.h> for all
architectures.

v8:
	* remove garbage after commit-message tags
v6:
	* fix fb_readq()/fb_writeq() on 64-bit mips (kernel test robot)
v5:
	* include <linux/io.h> in <asm-generic/fb>; fix s390 build
v4:
	* ia64, loongarch, sparc64: add fb_mem*() to arch headers
	  to keep current semantics (Arnd)
v3:
	* implement all architectures with generic helpers
	* support reordering and native byte order (Geert, Arnd)

Signed-off-by: default avatarThomas Zimmermann <tzimmermann@suse.de>
Tested-by: default avatarSui Jingfeng <suijingfeng@loongson.cn>
Reviewed-by: default avatarArnd Bergmann <arnd@arndb.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20230512102444.5438-7-tzimmermann@suse.de
parent 8ff1541d

arch/ia64/include/asm/fb.h

+20 −0
Original line number Diff line number Diff line
@@ -2,7 +2,9 @@ 
#ifndef _ASM_FB_H_

#define _ASM_FB_H_



#include <linux/compiler.h>

#include <linux/efi.h>

#include <linux/string.h>



#include <asm/page.h>
@@ -18,6 +20,24 @@ static inline void fb_pgprotect(struct file *file, struct vm_area_struct *vma, 
}

#define fb_pgprotect fb_pgprotect



static inline void fb_memcpy_fromfb(void *to, const volatile void __iomem *from, size_t n)

{

	memcpy(to, (void __force *)from, n);

}

#define fb_memcpy_fromfb fb_memcpy_fromfb



static inline void fb_memcpy_tofb(volatile void __iomem *to, const void *from, size_t n)

{

	memcpy((void __force *)to, from, n);

}

#define fb_memcpy_tofb fb_memcpy_tofb



static inline void fb_memset(volatile void __iomem *addr, int c, size_t n)

{

	memset((void __force *)addr, c, n);

}

#define fb_memset fb_memset



#include <asm-generic/fb.h>



#endif /* _ASM_FB_H_ */

arch/loongarch/include/asm/fb.h

+21 −0
Original line number Diff line number Diff line
@@ -5,6 +5,27 @@ 
#ifndef _ASM_FB_H_

#define _ASM_FB_H_



#include <linux/compiler.h>

#include <linux/string.h>



static inline void fb_memcpy_fromfb(void *to, const volatile void __iomem *from, size_t n)

{

	memcpy(to, (void __force *)from, n);

}

#define fb_memcpy_fromfb fb_memcpy_fromfb



static inline void fb_memcpy_tofb(volatile void __iomem *to, const void *from, size_t n)

{

	memcpy((void __force *)to, from, n);

}

#define fb_memcpy_tofb fb_memcpy_tofb



static inline void fb_memset(volatile void __iomem *addr, int c, size_t n)

{

	memset((void __force *)addr, c, n);

}

#define fb_memset fb_memset



#include <asm-generic/fb.h>



#endif /* _ASM_FB_H_ */

arch/mips/include/asm/fb.h

+22 −0
Original line number Diff line number Diff line
@@ -12,6 +12,28 @@ static inline void fb_pgprotect(struct file *file, struct vm_area_struct *vma, 
}

#define fb_pgprotect fb_pgprotect



/*

 * MIPS doesn't define __raw_ I/O macros, so the helpers

 * in <asm-generic/fb.h> don't generate fb_readq() and

 * fb_write(). We have to provide them here.

 *

 * TODO: Convert MIPS to generic I/O. The helpers below can

 *       then be removed.

 */

#ifdef CONFIG_64BIT

static inline u64 fb_readq(const volatile void __iomem *addr)

{

	return __raw_readq(addr);

}

#define fb_readq fb_readq



static inline void fb_writeq(u64 b, volatile void __iomem *addr)

{

	__raw_writeq(b, addr);

}

#define fb_writeq fb_writeq

#endif



#include <asm-generic/fb.h>



#endif /* _ASM_FB_H_ */

arch/sparc/include/asm/fb.h

+20 −0
Original line number Diff line number Diff line
@@ -2,6 +2,8 @@ 
#ifndef _SPARC_FB_H_

#define _SPARC_FB_H_



#include <linux/io.h>



struct fb_info;

struct file;

struct vm_area_struct;
@@ -16,6 +18,24 @@ static inline void fb_pgprotect(struct file *file, struct vm_area_struct *vma, 
int fb_is_primary_device(struct fb_info *info);

#define fb_is_primary_device fb_is_primary_device



static inline void fb_memcpy_fromfb(void *to, const volatile void __iomem *from, size_t n)

{

	sbus_memcpy_fromio(to, from, n);

}

#define fb_memcpy_fromfb fb_memcpy_fromfb



static inline void fb_memcpy_tofb(volatile void __iomem *to, const void *from, size_t n)

{

	sbus_memcpy_toio(to, from, n);

}

#define fb_memcpy_tofb fb_memcpy_tofb



static inline void fb_memset(volatile void __iomem *addr, int c, size_t n)

{

	sbus_memset_io(addr, c, n);

}

#define fb_memset fb_memset



#include <asm-generic/fb.h>



#endif /* _SPARC_FB_H_ */

include/asm-generic/fb.h

+102 −0
Original line number Diff line number Diff line
@@ -7,6 +7,7 @@ 
 * Only include this header file from your architecture's <asm/fb.h>.

 */



#include <linux/io.h>

#include <linux/mm_types.h>

#include <linux/pgtable.h>
@@ -30,4 +31,105 @@ static inline int fb_is_primary_device(struct fb_info *info) 
}

#endif



/*

 * I/O helpers for the framebuffer. Prefer these functions over their

 * regular counterparts. The regular I/O functions provide in-order

 * access and swap bytes to/from little-endian ordering. Neither is

 * required for framebuffers. Instead, the helpers read and write

 * raw framebuffer data. Independent operations can be reordered for

 * improved performance.

 */



#ifndef fb_readb

static inline u8 fb_readb(const volatile void __iomem *addr)

{

	return __raw_readb(addr);

}

#define fb_readb fb_readb

#endif



#ifndef fb_readw

static inline u16 fb_readw(const volatile void __iomem *addr)

{

	return __raw_readw(addr);

}

#define fb_readw fb_readw

#endif



#ifndef fb_readl

static inline u32 fb_readl(const volatile void __iomem *addr)

{

	return __raw_readl(addr);

}

#define fb_readl fb_readl

#endif



#ifndef fb_readq

#if defined(__raw_readq)

static inline u64 fb_readq(const volatile void __iomem *addr)

{

	return __raw_readq(addr);

}

#define fb_readq fb_readq

#endif

#endif



#ifndef fb_writeb

static inline void fb_writeb(u8 b, volatile void __iomem *addr)

{

	__raw_writeb(b, addr);

}

#define fb_writeb fb_writeb

#endif



#ifndef fb_writew

static inline void fb_writew(u16 b, volatile void __iomem *addr)

{

	__raw_writew(b, addr);

}

#define fb_writew fb_writew

#endif



#ifndef fb_writel

static inline void fb_writel(u32 b, volatile void __iomem *addr)

{

	__raw_writel(b, addr);

}

#define fb_writel fb_writel

#endif



#ifndef fb_writeq

#if defined(__raw_writeq)

static inline void fb_writeq(u64 b, volatile void __iomem *addr)

{

	__raw_writeq(b, addr);

}

#define fb_writeq fb_writeq

#endif

#endif



#ifndef fb_memcpy_fromfb

static inline void fb_memcpy_fromfb(void *to, const volatile void __iomem *from, size_t n)

{

	memcpy_fromio(to, from, n);

}

#define fb_memcpy_fromfb fb_memcpy_fromfb

#endif



#ifndef fb_memcpy_tofb

static inline void fb_memcpy_tofb(volatile void __iomem *to, const void *from, size_t n)

{

	memcpy_toio(to, from, n);

}

#define fb_memcpy_tofb fb_memcpy_tofb

#endif



#ifndef fb_memset

static inline void fb_memset(volatile void __iomem *addr, int c, size_t n)

{

	memset_io(addr, c, n);

}

#define fb_memset fb_memset

#endif



#endif /* __ASM_GENERIC_FB_H_ */