Hwpktpoll - Mini-Driver Polling Function; Configuration Variables - Texas Instruments TMS320C6000 Design Manual

3.3.7 _HwPktPoll — Mini-Driver Polling Function
Syntax
Parameters
Return Value
Description
3.4

Configuration Variables

void _HwPktPoll( PDINFO *pi, uint fTimerTick );
pi - Pointer to Ethernet packet device instance structure.
fTimerTick - Flag indicating whether this function has been called
because the 100 ms timer expired or if it was called by some other
function randomly.
None
This function is called by the NIMU layer at least every 100 ms, but calls
can come faster when there is network activity. The mini-driver is not
required to perform any operation in this function, but it can be used to
check for device lockup conditions. When the call is made due to the 100
ms time tick, the fTimerTick calling parameter is set.
Note that this function is not called in kernel mode (hence, the underscore
in the name). This is the only mini-driver function called from outside
kernel mode (to support polling drivers).
The following configuration variables are defined by the Ethernet mini-
driver layer to control various features:
❏ EXTERNAL_MEMORY. Enable this flag to compile the code to
support the cache cleaning and synchronization required when the
packet buffer memory is allocated from external memory.
❏ EXTMEM. Define this bit mask to indicate the external memory
address location for this platform.
❏ PKT_MAX. Use this constant to control the number of "EMAC_Pkt"
type packet buffers that are allocated and initialized on Receive and
Transmit paths respectively at this layer to optimize the data paths.
During EMAC start up, in the HwPktOpen() function, buffers of type
"EMAC_Pkt" structure are allocated and enqueued to a free
queue/receive queue. Packets from this "RxQueue" are used to
replenish the CSL layer with buffers for its BDs. Similarly, for the Tx
path a queue of such EMAC_Pkt initialized structures are held. A
packet buffer from the "TxQueue" is dequeued and used in filling up
the NDK packet buffer details before being handed over to the CSL
layer. This constant controls the number of such replenishing buffers
at this layer.

Configuration Variables

Ethernet Mini-Driver Layer 3-7