MPC8536E-ANDROID Freescale Semiconductor, MPC8536E-ANDROID Datasheet - Page 924

• Manufacturer Part Number: MPC8536E-ANDROID
• Description: HARDWARE/SOFTWARE ANDROID OS
• Manufacturer: Freescale Semiconductor
• Series: PowerQUICC ™r
• Type: MPUr

Specifications of MPC8536E-ANDROID

• Contents: Board
• For Use With/related Products: MPC8536
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Enhanced Three-Speed Ethernet Controllers
14.6.4
Each eTSEC provides hardware support for accelerating the basic functions of TCP/IP packet transmission
and reception. By default, these features are disabled and must be explicitly enabled through RCTRL and
TCTRL. In this configuration, the eTSEC processes frames as vanilla Ethernet frames and none of the
multi-ring QoS/CoS receive services or per-frame VLAN insertion and deletion are available. Operate
eTSEC in this default configuration when using existing TCP/IP stack software that has not been modified
to take advantage of TOE.
TOE can be enabled independently for Rx and Tx and at various levels. Receive TOE functions are
controlled by RCTRL and transmit functions through a combination of TCTRL[TUCSEN] and the Tx
frame control block.
On receive, according to RCTRL[PRSDEP], eTSEC can parse frames at layer 2 of the stack only (Ethernet
headers and switching headers), layers 2 to 3 (including IPv4 or IPv6), or layers 2 to 4 (including TCP and
14-176
Filed frame to invalid
queue error
Parser error
Non-octet error
(dribbling bits)
CRC error
Memory read error
Data parity error
Babbling receive error
Error
TCP/IP Off-Load
MPC8536E PowerQUICC III Integrated Processor Reference Manual, Rev. 1
A frame is received and discarded as a result of the filer directing it to an RxBD ring that is currently
not enabled. The controller sets IEVENT[FIQ] and increments the discarded frame counter (RDRP).
If the receive frame parser is enabled, a parse error can be flagged as a result of inconsistencies dis-
covered between fields of the embedded packet headers. For example, the L2 header may indicate
an IPv4 header, but the IP version number fails to match. In the event of a parse error, parsing is ter-
minated at the inconsistent header, and the RxFCB[PERR] field indicates at which layer of the proto-
col stack the error was discovered. Receiver function continues regardless of parse errors, but
IEVENT[PERR] is set. The receive queue filer may operate with reduced or default information in
some cases; therefore, filer rule sets should be constructed so as to be tolerant of misformed frames.
Note: Any values in the length/type field between 1500 and 1536 is treated as a length, however, only
illegal packets exist with this length/type since these are not valid lengths and not valid types. These
are treated by the MAC logic as out of range.
Software must confirm the parser and filer results by checking the type/length field after the packet has
been written to memory to see if it falls in this range.
The Ethernet controller handles a nibble of dribbling bits if the receive frame terminates as non-octet
aligned and it checks the CRC of the frame on the last octet boundary. If there is a CRC error, the
frame non-octet aligned (RxBD[NO]) error is reported, IEVENT[RXF] is set, and the alignment error
counter increments. The eTSEC relies on the statistics collector block to increment the receive
alignment error counter (RALN). If there is no CRC error, no error is reported.
If a CRC error occurs, the controller sets RxBD[CR], closes the buffer, and sets IEVENT[RXF]. This
eTSEC relies on the statistics collector block to record the event. After receiving a frame with a CRC
error, the receiver then enters hunt mode.
A system bus error occurred during a DMA transaction. The controller sets IEVENT[EBERR] and
discards the frame and increments the discarded frame counter (RDRP). In addition the
RSTAT[QHLT n ] bit is set. The halted queue resumes reception once the RSTAT[QHLT n ] bit is cleared.
Data in the receive FIFO or filer table was potentially corrupted. The controller sets IEVENT[DPE], but
otherwise continues reception until halted explicitly.
A frame is received that exceeds the MAC’s maximum frame length. The controller sets
IEVENT[BABR] and continues.
Table 14-157. Reception Errors (continued)
Description
Freescale Semiconductor