arch/parisc/include/asm/io.h

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

File Facts

System
Linux kernel
Corpus path
arch/parisc/include/asm/io.h
Extension
.h
Size
7443 bytes
Lines
284
Domain
Architecture Layer
Bucket
arch/parisc
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

static inline unsigned long isa_bus_to_virt(unsigned long addr) {
	BUG();
	return 0;
}

static inline unsigned long isa_virt_to_bus(void *addr) {
	BUG();
	return 0;
}

/*
 * Memory mapped I/O
 *
 * readX()/writeX() do byteswapping and take an ioremapped address
 * __raw_readX()/__raw_writeX() don't byteswap and take an ioremapped address.
 * gsc_*() don't byteswap and operate on physical addresses;
 *   eg dev->hpa or 0xfee00000.
 */

static inline unsigned char gsc_readb(unsigned long addr)
{
	long flags;
	unsigned char ret;

	__asm__ __volatile__(
	"	rsm	%3,%0\n"
	"	ldbx	0(%2),%1\n"
	"	mtsm	%0\n"
	: "=&r" (flags), "=r" (ret) : "r" (addr), "i" (PSW_SM_D) );

	return ret;
}

static inline unsigned short gsc_readw(unsigned long addr)
{
	long flags;
	unsigned short ret;

	__asm__ __volatile__(
	"	rsm	%3,%0\n"
	"	ldhx	0(%2),%1\n"
	"	mtsm	%0\n"
	: "=&r" (flags), "=r" (ret) : "r" (addr), "i" (PSW_SM_D) );

	return ret;
}

static inline unsigned int gsc_readl(unsigned long addr)
{
	u32 ret;

	__asm__ __volatile__(
	"	ldwax	0(%1),%0\n"
	: "=r" (ret) : "r" (addr) );

	return ret;
}

static inline unsigned long long gsc_readq(unsigned long addr)
{
	unsigned long long ret;

#ifdef CONFIG_64BIT
	__asm__ __volatile__(
	"	ldda	0(%1),%0\n"
	:  "=r" (ret) : "r" (addr) );
#else
	/* two reads may have side effects.. */
	ret = ((u64) gsc_readl(addr)) << 32;
	ret |= gsc_readl(addr+4);
#endif
	return ret;
}

static inline void gsc_writeb(unsigned char val, unsigned long addr)
{
	long flags;
	__asm__ __volatile__(
	"	rsm	%3,%0\n"
	"	stbs	%1,0(%2)\n"
	"	mtsm	%0\n"
	: "=&r" (flags) :  "r" (val), "r" (addr), "i" (PSW_SM_D) );
}

static inline void gsc_writew(unsigned short val, unsigned long addr)
{
	long flags;
	__asm__ __volatile__(
	"	rsm	%3,%0\n"
	"	sths	%1,0(%2)\n"

Annotation

Implementation Notes