misc/cb710/sgbuf2.c

11 static bool sg_dwiter_next(struct sg_mapping_iter *miter)
13 	if (sg_miter_next(miter)) {
14 		miter->consumed = 0;
20 static bool sg_dwiter_is_at_end(struct sg_mapping_iter *miter)
22 	return miter->length == miter->consumed && !sg_dwiter_next(miter);
25 static uint32_t sg_dwiter_read_buffer(struct sg_mapping_iter *miter)
32 		len = min(miter->length - miter->consumed, left);
33 		memcpy(addr, miter->addr + miter->consumed, len);
34 		miter->consumed += len;
39 	} while (sg_dwiter_next(miter));
54 static bool sg_dwiter_get_next_block(struct sg_mapping_iter *miter, uint32_t **ptr)
58 	if (sg_dwiter_is_at_end(miter))
61 	len = miter->length - miter->consumed;
64 			miter->addr + miter->consumed))) {
65 		*ptr = miter->addr + miter->consumed;
66 		miter->consumed += 4;
75  * @miter: sg mapping iterator used for reading
78  *   Returns 32-bit word starting at byte pointed to by @miter@
80  *   are not accessed (read) but are returned as zeroes.  @miter@
90 uint32_t cb710_sg_dwiter_read_next_block(struct sg_mapping_iter *miter)
94 	if (likely(sg_dwiter_get_next_block(miter, &ptr)))
97 	return sg_dwiter_read_buffer(miter);
101 static void sg_dwiter_write_slow(struct sg_mapping_iter *miter, uint32_t data)
107 		len = min(miter->length - miter->consumed, left);
108 		memcpy(miter->addr, addr, len);
109 		miter->consumed += len;
114 	} while (sg_dwiter_next(miter));
119  * @miter: sg mapping iterator used for writing
123  *   Writes 32-bit word starting at byte pointed to by @miter@
125  *   past the buffer's end are silently discarded. @miter@ is
131 void cb710_sg_dwiter_write_next_block(struct sg_mapping_iter *miter, uint32_t data)
135 	if (likely(sg_dwiter_get_next_block(miter, &ptr))) {
141 		sg_dwiter_write_slow(miter, data);