arch/nios2/include/asm/io.h

Source file repositories/reference/linux-study-clean/arch/nios2/include/asm/io.h

File Facts

System
Linux kernel
Corpus path
arch/nios2/include/asm/io.h
Extension
.h
Size
1222 bytes
Lines
41
Domain
Architecture Layer
Bucket
arch/nios2
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_NIOS2_IO_H
#define _ASM_NIOS2_IO_H

#include <linux/types.h>
#include <asm/pgtable-bits.h>

/* PCI is not supported in nios2, set this to 0. */
#define IO_SPACE_LIMIT 0

#define readb_relaxed(addr)	readb(addr)
#define readw_relaxed(addr)	readw(addr)
#define readl_relaxed(addr)	readl(addr)

#define writeb_relaxed(x, addr)	writeb(x, addr)
#define writew_relaxed(x, addr)	writew(x, addr)
#define writel_relaxed(x, addr)	writel(x, addr)

void __iomem *ioremap(unsigned long physaddr, unsigned long size);
void iounmap(void __iomem *addr);

/* Macros used for converting between virtual and physical mappings. */
#define phys_to_virt(vaddr)	\
	((void *)((unsigned long)(vaddr) | CONFIG_NIOS2_KERNEL_REGION_BASE))
/* Clear top 3 bits */
#define virt_to_phys(vaddr)	\
	((unsigned long)((unsigned long)(vaddr) & ~0xE0000000))

#include <asm-generic/io.h>

#endif /* _ASM_NIOS2_IO_H */

Annotation

Implementation Notes