NHE6300ESB S L7XJ Intel, NHE6300ESB S L7XJ Datasheet - Page 206

• Manufacturer Part Number: NHE6300ESB S L7XJ
• Manufacturer: Intel

Specifications of NHE6300ESB S L7XJ

• Lead Free Status / RoHS Status: Compliant

Table 95.
Intel
DS
206
®
6300ESB I/O Controller Hub
by writing the just-executed TD’s link pointer back into the QH’s Queue Element link
pointer. The next time the queue head is traversed, the next queue element will be the
Top element.
The traversal has two options: Breadth first, or Depth first. A flag bit in each TD (Vf -
Vertical Traversal Flag) controls whether traversal is Breadth or Depth first. The default
mode of traversal is Breadth-First. For Breadth-First, the Intel
executes the top element from each queue. The execution path is shown below:
Breadth-First is also performed for every transaction execution that fails the advance
criteria. This means that when a queued TD fails, the queue does not advance and the
Intel
In a Depth-first traversal, the top queue element must complete successfully to satisfy
the advance criteria for the queue. When the Intel
processing a queue, and the advance criteria are met, and the Vf bit is set, the Intel
6300ESB ICH follows the TD’s link pointer to the next schedule work item.
Note that regardless of traversal model, when the advance criteria are met, the
successful TD’s link pointer is written back to the QH’s Queue Element link pointer.
When the Intel
internal state to indicate it is in a Q-context. It needs this state to update the correct
QH (for auto advancement) and also to make the correct decisions on how to traverse
the Frame List.
Restricting the advancement of queues to advancement criteria implements an ensured
data delivery stream.
A queue is never advanced on an error completion status (even in the event the error
count was exhausted).
Table 95
status of the TD at the “Top” of a currently “active” queue.
Queue Advance Criteria
Table 96
the valid actions taken when advancement criteria for a queued transfer descriptor are
met. The column headings for the link pointer fields are encoded, based on the
following list:
1. QH (Queue Element Link Pointer)
2. TD
3. Write-Back to QH (Queue Element Link Pointer)
4. QH (Queue Head Link pointer).
Non-NULL
Advance Q
®
6300ESB ICH traverses the QH’s Queue Head Link Pointer.
lists the general queue advance criteria, which are based on the execution
is a decision table illustrating the valid combinations of link pointer bits and
Function-to-Host (IN)
Advance Q
®
NULL
6300ESB ICH encounters a QH, it caches the QH internally, and sets
Retry Q Element
Error/NAK
Non-NULL
Advance Q
®
Host-to-Function (OUT)
6300ESB ICH is currently
Advance Q
NULL
®
Order Number: 300641-004US
6300ESB ICH only
Intel
Retry Q Element
®
Error/NAK
6300ESB ICH—5
November 2007
®