Internal Modules
251
SPRUHI7A – December 2012 – Revised June 2016
Copyright © 2012–2016, Texas Instruments Incorporated
High-Definition Video Processing Subsystem (HDVPSS)
Table 1-98. Send Interrupt Field Descriptions (Word - 3)
Bits
Name
Description
31-27
Packet Type
Host Packet Descriptor Type = Ch
26-24
Reserved
Reserved
23-16
Source
Specifies the source used for the control
event.
15-4
Reserved
Reserved for future use
3-0
Control
Control type = 6h
1.2.13.3.3.3.7 Reload List
A Reload List descriptor causes ending descriptors after this descriptor in the original list to be dropped
and a new list at the location and of the size specified in the descriptor. This descriptor can be used to
allow for linked lists in the VPDMA as the list will continue from this point and fetch the list specified and it
does not have to be continuous with the current list. The NULL bit in the first word determines if it is a
valid address. If the NULL bit is set then the list will not fetch that address until a doorbell is received.
Upon receiving the doorbell the reload list descriptor will be refetched from memory and then the new list
address will be used along with list size to fetch the next section of the list. This allows for the list to be
dynamically adding new sections of a list.
The procedure to use a reload list descriptor as a mechanism to allow dynamic additions to a list is as
follows. A list section is created and the last descriptor in the section is a reload list with a NULL bit set.
When a new section of the list is created the last descriptor in the list will be a Reload List with the NULL
bit set. The software then updates the address and size in the Reload List descriptor in the previous
section and then writes to the LIST_ATTRIBUTE register with the list number and the list type set to
doorbell. This will create an immediate pulse that the hardware will latch until it does another list fetch.
Software can do this as many times as it wants to keep adding to the list. Word 2 is reserved.
Table 1-99. Reload List Field Descriptions (Word - 0)
Bits
Name
Description
31-1
LIST_ADDRESS
31 most-significant Bits of the memory
address where the descriptors to be
loaded are stored. Address must be 16
byte aligned.
0
NULL
Specify whether “doorbell” SW trigger is
used.
Table 1-100. Reload List Field Descriptions (Word - 1)
Bits
Name
Description
31-16
Reserved
Reserved
15-0
LIST_SIZE
Size of the list to load
Table 1-101. Reload List Field Descriptions (Word - 3)
Bits
Name
Description
31-27
Packet Type
Host Packet Descriptor Type = Ch
26-4
Reserved
Reserved
3-0
Control
Control type = 7h
