Texas Instruments TMS320C645x manual RX Buffer Descriptor Field Descriptions

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	SRIO Functional Description
	Table 17. RX Buffer Descriptor Field Descriptions
Field	Description
next_descriptor_pointer	Next Descriptor Pointer: The 32-bit word aligned memory address of the next buffer
	descriptor in the RX queue. This references the next buffer descriptor from the current
	buffer descriptor. If the value of this pointer is zero, then the current buffer is the last
	buffer in the queue. The host sets the next_descriptor_pointer.
buffer_pointer	Buffer Pointer: The byte aligned memory address of the buffer associated with the
	buffer descriptor. The host sets the buffer_pointer.
Sop = 1	Start of Message: Indicates that the descriptor buffer is the first buffer in the message.
	∙ This bit will always be set, as this device only supports one buffer per message.
Eop = 1	End of Message: Indicates that the descriptor buffer is the last buffer in the message.
	∙ This bit will always be set, as this device only supports one buffer per message.
ownership	Ownership: Indicates ownership of the message and is valid only on sop. This bit is set
	by the host and cleared by the port when the message has been transmitted. The host
	uses this bit to reclaim buffers.
	0: The message is owned by the host
	1: The message is owned by the port
eoq	End Of Queue: Set by the port to indicate that the RX queue empty condition exists.
	This bit is valid only on eop. The port determines the end of queue condition by a zero
	next_descriptor_pointer.
	0: The RX queue has more buffers available for reception.
	1: The Descriptor buffer is the last buffer in the last message in the queue.
Teardown_Complete	Teardown Complete: Set by the port to indicate that the host commanded teardown
	process is complete, and the channel buffers may be reclaimed by the host.
	0: The port has not completed the teardown process.
	1: The port has completed the commanded teardown process.
message_length	Message Length: Initially written by the CPU to specify the maximum number of
	double-words the buffer can receive. Updated by the peripheral (after receiving a
	message) to indicate the actual number of double-words in the entire message.
	Message payloads are limited to a maximum size of 512 double-words (4096bytes).
	000000000b: 512 double words
	000000001b: 1 double word
	000000010b: 2 double words
	. . .
	111111111b: 511 double words
Src_id	Source Node ID: Unique node identifier of the source of the message.
tt	RapidIO tt field specifying 8- or 16-bit DeviceIDs
	00: 8b deviceIDs
	01: 16b deviceIDs
	10: reserved
	11: reserved
pri	Message Priority: Specifies the SRIO priority at which the message was sent.
cc	Completion Code:
	000: Good completion. Message received.
	001: Error, RX message length greater than supported buffer descriptor
	message_length
	010: Error, TimeOut on receiving one of the segments
	011: DMA transfer error on one or more segments
	100: Queue teardown completed, data invalid
	101: 111 Reserved

SPRU976 –March 2006	Serial RapidIO (SRIO)	45
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