bus.h

基于组件方式开发操作系统的OSKIT源代码

		while (count--)
			*(volatile u_int32_t *)(addr) = value;
#endif
}

#if 0	/* Cause a link error for bus_space_set_multi_8 */
#define	bus_space_set_multi_8 !!! bus_space_set_multi_8 unimplemented !!!
#endif

/*
 * Write `count' 1, 2, 4, or 8 byte value `val' to bus space described
 * by tag/handle starting at `offset'.
 */

static __inline void bus_space_set_region_1(bus_space_tag_t tag,
					    bus_space_handle_t bsh,
					    bus_size_t offset, u_int8_t value,
					    size_t count);
static __inline void bus_space_set_region_2(bus_space_tag_t tag,
					    bus_space_handle_t bsh,
					    bus_size_t offset, u_int16_t value,
					    size_t count);
static __inline void bus_space_set_region_4(bus_space_tag_t tag,
					    bus_space_handle_t bsh,
					    bus_size_t offset, u_int32_t value,
					    size_t count);

static __inline void
bus_space_set_region_1(bus_space_tag_t tag, bus_space_handle_t bsh,
		       bus_size_t offset, u_int8_t value, size_t count)
{
	bus_addr_t addr = bsh + offset;

#if defined(_I386_BUS_PIO_H_)
#if defined(_I386_BUS_MEMIO_H_)
	if (tag == I386_BUS_SPACE_IO)
#endif
		for (; count != 0; count--, addr++)
			outb(addr, value);
#endif
#if defined(_I386_BUS_MEMIO_H_)
#if defined(_I386_BUS_PIO_H_)
	else
#endif
		for (; count != 0; count--, addr++)
			*(volatile u_int8_t *)(addr) = value;
#endif
}

static __inline void
bus_space_set_region_2(bus_space_tag_t tag, bus_space_handle_t bsh,
		       bus_size_t offset, u_int16_t value, size_t count)
{
	bus_addr_t addr = bsh + offset;

#if defined(_I386_BUS_PIO_H_)
#if defined(_I386_BUS_MEMIO_H_)
	if (tag == I386_BUS_SPACE_IO)
#endif
		for (; count != 0; count--, addr += 2)
			outw(addr, value);
#endif
#if defined(_I386_BUS_MEMIO_H_)
#if defined(_I386_BUS_PIO_H_)
	else
#endif
		for (; count != 0; count--, addr += 2)
			*(volatile u_int16_t *)(addr) = value;
#endif
}

static __inline void
bus_space_set_region_4(bus_space_tag_t tag, bus_space_handle_t bsh,
		       bus_size_t offset, u_int32_t value, size_t count)
{
	bus_addr_t addr = bsh + offset;

#if defined(_I386_BUS_PIO_H_)
#if defined(_I386_BUS_MEMIO_H_)
	if (tag == I386_BUS_SPACE_IO)
#endif
		for (; count != 0; count--, addr += 4)
			outl(addr, value);
#endif
#if defined(_I386_BUS_MEMIO_H_)
#if defined(_I386_BUS_PIO_H_)
	else
#endif
		for (; count != 0; count--, addr += 4)
			*(volatile u_int32_t *)(addr) = value;
#endif
}

#if 0	/* Cause a link error for bus_space_set_region_8 */
#define	bus_space_set_region_8	!!! bus_space_set_region_8 unimplemented !!!
#endif

/*
 * Copy `count' 1, 2, 4, or 8 byte values from bus space starting
 * at tag/bsh1/off1 to bus space starting at tag/bsh2/off2.
 */

static __inline void bus_space_copy_region_1(bus_space_tag_t tag,
					     bus_space_handle_t bsh1,
					     bus_size_t off1,
					     bus_space_handle_t bsh2,
					     bus_size_t off2, size_t count);

static __inline void bus_space_copy_region_2(bus_space_tag_t tag,
					     bus_space_handle_t bsh1,
					     bus_size_t off1,
					     bus_space_handle_t bsh2,
					     bus_size_t off2, size_t count);

static __inline void bus_space_copy_region_4(bus_space_tag_t tag,
					     bus_space_handle_t bsh1,
					     bus_size_t off1,
					     bus_space_handle_t bsh2,
					     bus_size_t off2, size_t count);

static __inline void
bus_space_copy_region_1(bus_space_tag_t tag, bus_space_handle_t bsh1,
			bus_size_t off1, bus_space_handle_t bsh2,
			bus_size_t off2, size_t count)
{
	bus_addr_t addr1 = bsh1 + off1;
	bus_addr_t addr2 = bsh2 + off2;

#if defined(_I386_BUS_PIO_H_)
#if defined(_I386_BUS_MEMIO_H_)
	if (tag == I386_BUS_SPACE_IO)
#endif
	{
		if (addr1 >= addr2) {
			/* src after dest: copy forward */
			for (; count != 0; count--, addr1++, addr2++)
				outb(addr2, inb(addr1));
		} else {
			/* dest after src: copy backwards */
			for (addr1 += (count - 1), addr2 += (count - 1);
			    count != 0; count--, addr1--, addr2--)
				outb(addr2, inb(addr1));
		}
	}
#endif
#if defined(_I386_BUS_MEMIO_H_)
#if defined(_I386_BUS_PIO_H_)
	else
#endif
	{
		if (addr1 >= addr2) {
			/* src after dest: copy forward */
			for (; count != 0; count--, addr1++, addr2++)
				*(volatile u_int8_t *)(addr2) =
				    *(volatile u_int8_t *)(addr1);
		} else {
			/* dest after src: copy backwards */
			for (addr1 += (count - 1), addr2 += (count - 1);
			    count != 0; count--, addr1--, addr2--)
				*(volatile u_int8_t *)(addr2) =
				    *(volatile u_int8_t *)(addr1);
		}
	}
#endif
}

static __inline void
bus_space_copy_region_2(bus_space_tag_t tag, bus_space_handle_t bsh1,
			bus_size_t off1, bus_space_handle_t bsh2,
			bus_size_t off2, size_t count)
{
	bus_addr_t addr1 = bsh1 + off1;
	bus_addr_t addr2 = bsh2 + off2;

#if defined(_I386_BUS_PIO_H_)
#if defined(_I386_BUS_MEMIO_H_)
	if (tag == I386_BUS_SPACE_IO)
#endif
	{
		if (addr1 >= addr2) {
			/* src after dest: copy forward */
			for (; count != 0; count--, addr1 += 2, addr2 += 2)
				outw(addr2, inw(addr1));
		} else {
			/* dest after src: copy backwards */
			for (addr1 += 2 * (count - 1), addr2 += 2 * (count - 1);
			    count != 0; count--, addr1 -= 2, addr2 -= 2)
				outw(addr2, inw(addr1));
		}
	}
#endif
#if defined(_I386_BUS_MEMIO_H_)
#if defined(_I386_BUS_PIO_H_)
	else
#endif
	{
		if (addr1 >= addr2) {
			/* src after dest: copy forward */
			for (; count != 0; count--, addr1 += 2, addr2 += 2)
				*(volatile u_int16_t *)(addr2) =
				    *(volatile u_int16_t *)(addr1);
		} else {
			/* dest after src: copy backwards */
			for (addr1 += 2 * (count - 1), addr2 += 2 * (count - 1);
			    count != 0; count--, addr1 -= 2, addr2 -= 2)
				*(volatile u_int16_t *)(addr2) =
				    *(volatile u_int16_t *)(addr1);
		}
	}
#endif
}

static __inline void
bus_space_copy_region_4(bus_space_tag_t tag, bus_space_handle_t bsh1,
			bus_size_t off1, bus_space_handle_t bsh2,
			bus_size_t off2, size_t count)
{
	bus_addr_t addr1 = bsh1 + off1;
	bus_addr_t addr2 = bsh2 + off2;

#if defined(_I386_BUS_PIO_H_)
#if defined(_I386_BUS_MEMIO_H_)
	if (tag == I386_BUS_SPACE_IO)
#endif
	{
		if (addr1 >= addr2) {
			/* src after dest: copy forward */
			for (; count != 0; count--, addr1 += 4, addr2 += 4)
				outl(addr2, inl(addr1));
		} else {
			/* dest after src: copy backwards */
			for (addr1 += 4 * (count - 1), addr2 += 4 * (count - 1);
			    count != 0; count--, addr1 -= 4, addr2 -= 4)
				outl(addr2, inl(addr1));
		}
	}
#endif
#if defined(_I386_BUS_MEMIO_H_)
#if defined(_I386_BUS_PIO_H_)
	else
#endif
	{
		if (addr1 >= addr2) {
			/* src after dest: copy forward */
			for (; count != 0; count--, addr1 += 4, addr2 += 4)
				*(volatile u_int32_t *)(addr2) =
				    *(volatile u_int32_t *)(addr1);
		} else {
			/* dest after src: copy backwards */
			for (addr1 += 4 * (count - 1), addr2 += 4 * (count - 1);
			    count != 0; count--, addr1 -= 4, addr2 -= 4)
				*(volatile u_int32_t *)(addr2) =
				    *(volatile u_int32_t *)(addr1);
		}
	}
#endif
}

#endif /* defined(_I386_BUS_PIO_H_) || defined(_I386_MEM_IO_H_) */

#if 0	/* Cause a link error for bus_space_copy_8 */
#define	bus_space_copy_region_8	!!! bus_space_copy_region_8 unimplemented !!!
#endif

/*
 * Bus read/write barrier methods.
 *
 *	void bus_space_barrier(bus_space_tag_t tag, bus_space_handle_t bsh,
 *			       bus_size_t offset, bus_size_t len, int flags);
 *
 * Note: the i386 does not currently require barriers, but we must
 * provide the flags to MI code.
 */
#define	bus_space_barrier(t, h, o, l, f)	\
	((void)((void)(t), (void)(h), (void)(o), (void)(l), (void)(f)))
#define	BUS_SPACE_BARRIER_READ	0x01		/* force read barrier */
#define	BUS_SPACE_BARRIER_WRITE	0x02		/* force write barrier */

/*
 * Flags used in various bus DMA methods.
 */
#define	BUS_DMA_WAITOK		0x00	/* safe to sleep (pseudo-flag) */
#define	BUS_DMA_NOWAIT		0x01	/* not safe to sleep */
#define	BUS_DMA_ALLOCNOW	0x02	/* perform resource allocation now */
#define	BUS_DMAMEM_NOSYNC	0x04	/* map memory to not require sync */
#define	BUS_DMA_BUS1		0x10	/* placeholders for bus functions... */
#define	BUS_DMA_BUS2		0x20
#define	BUS_DMA_BUS3		0x40
#define	BUS_DMA_BUS4		0x80

/* Forwards needed by prototypes below. */
struct mbuf;
struct uio;

/*
 *	bus_dmasync_op_t
 *
 *	Operations performed by bus_dmamap_sync().
 */
typedef enum {
	BUS_DMASYNC_PREREAD,
	BUS_DMASYNC_POSTREAD,
	BUS_DMASYNC_PREWRITE,
	BUS_DMASYNC_POSTWRITE
} bus_dmasync_op_t;

/*
 *	bus_dma_tag_t
 *
 *	A machine-dependent opaque type describing the characteristics
 *	of how to perform DMA mappings.  This structure encapsultes
 *	information concerning address and alignment restrictions, number
 *	of S/G	segments, amount of data per S/G segment, etc.
 */
typedef struct bus_dma_tag	*bus_dma_tag_t;

/*
 *	bus_dmamap_t
 *
 *	DMA mapping instance information.
 */
typedef struct bus_dmamap	*bus_dmamap_t;

/*
 *	bus_dma_segment_t
 *
 *	Describes a single contiguous DMA transaction.  Values
 *	are suitable for programming into DMA registers.
 */
typedef struct bus_dma_segment {
	bus_addr_t	ds_addr;	/* DMA address */
	bus_size_t	ds_len;		/* length of transfer */
} bus_dma_segment_t;

/*
 * A function that returns 1 if the address cannot be accessed by
 * a device and 0 if it can be.
 */
typedef int bus_dma_filter_t(void *, bus_addr_t);

/*
 * Allocate a device specific dma_tag encapsulating the constraints of
 * the parent tag in addition to other restrictions specified:
 *
 *	alignment:	alignment for segments.
 *	boundary:	Boundary that segments cannot cross.
 *	lowaddr:	Low restricted address that cannot appear in a mapping.
 *	highaddr:	High restricted address that cannot appear in a mapping.
 *	filtfunc:	An optional function to further test if an address
 *			within the range of lowaddr and highaddr cannot appear
 *			in a mapping.
 *	filtfuncarg:	An argument that will be passed to filtfunc in addition
 *			to the address to test.
 *	maxsize:	Maximum mapping size supported by this tag.
 *	nsegments:	Number of discontinuities allowed in maps.
 *	maxsegsz:	Maximum size of a segment in the map.
 *	flags:		Bus DMA flags.
 *	dmat:		A pointer to set to a valid dma tag should the return
 *			value of this function indicate success.
 */
/* XXX Should probably allow specification of alignment */
int bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignemnt,
		       bus_size_t boundary, bus_addr_t lowaddr,
		       bus_addr_t highaddr, bus_dma_filter_t *filtfunc,
		       void *filtfuncarg, bus_size_t maxsize, int nsegments,
		       bus_size_t maxsegsz, int flags, bus_dma_tag_t *dmat);

int bus_dma_tag_destroy(bus_dma_tag_t dmat);

/*
 * Allocate a handle for mapping from kva/uva/physical
 * address space into bus device space.
 */
int bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp);

/*
 * Destroy  a handle for mapping from kva/uva/physical
 * address space into bus device space.
 */
int bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map);

/*
 * Allocate a piece of memory that can be efficiently mapped into
 * bus device space based on the constraints lited in the dma tag.
 * A dmamap to for use with dmamap_load is also allocated.
 */
int bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
		     bus_dmamap_t *mapp);

/*
 * Free a piece of memory and it's allociated dmamap, that was allocated
 * via bus_dmamem_alloc.
 */
void bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map);

/*
 * A function that processes a successfully loaded dma map or an error
 * from a delayed load map.
 */
typedef void bus_dmamap_callback_t(void *, bus_dma_segment_t *, int, int);

/*
 * Map the buffer buf into bus space using the dmamap map.
 */
int bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf,
		    bus_size_t buflen, bus_dmamap_callback_t *callback,
		    void *callback_arg, int flags);

/*
 * Perform a syncronization operation on the given map.
 */
void _bus_dmamap_sync(bus_dma_tag_t, bus_dmamap_t, bus_dmasync_op_t);
#define bus_dmamap_sync(dmat, dmamap, op) 		\
	if ((dmamap) != NULL)				\
		_bus_dmamap_sync(dmat, dmamap, op)

/*
 * Release the mapping held by map.
 */
void _bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map);
#define bus_dmamap_unload(dmat, dmamap) 		\
	if ((dmamap) != NULL)				\
		_bus_dmamap_unload(dmat, dmamap)

#endif /* _I386_BUS_H_ */