arch/mips/include/asm/vga.h

Source file repositories/reference/linux-study-clean/arch/mips/include/asm/vga.h

File Facts

System
Linux kernel
Corpus path
arch/mips/include/asm/vga.h
Extension
.h
Size
1142 bytes
Lines
53
Domain
Architecture Layer
Bucket
arch/mips
Inferred role
Architecture Layer: implementation source
Status
source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

#ifndef _ASM_VGA_H
#define _ASM_VGA_H

#include <linux/string.h>
#include <asm/addrspace.h>
#include <asm/byteorder.h>

/*
 *	On the PC, we can just recalculate addresses and then
 *	access the videoram directly without any black magic.
 */

#define VGA_MAP_MEM(x, s)	CKSEG1ADDR(0x10000000L + (unsigned long)(x))

#define vga_readb(x)	(*(x))
#define vga_writeb(x, y)	(*(y) = (x))

#define VT_BUF_HAVE_RW
/*
 *  These are only needed for supporting VGA or MDA text mode, which use little
 *  endian byte ordering.
 *  In other cases, we can optimize by using native byte ordering and
 *  <linux/vt_buffer.h> has already done the right job for us.
 */

#undef scr_writew
#undef scr_readw

static inline void scr_writew(u16 val, volatile u16 *addr)
{
	*addr = cpu_to_le16(val);
}

static inline u16 scr_readw(volatile const u16 *addr)
{
	return le16_to_cpu(*addr);
}

static inline void scr_memsetw(u16 *s, u16 v, unsigned int count)
{
	memset16(s, cpu_to_le16(v), count / 2);
}

#define VT_BUF_HAVE_MEMSETW

#endif /* _ASM_VGA_H */

Annotation

Implementation Notes