User Manual
BCM1250/BCM1125/BCM1125H
10/21/02
B r o a d c o m C o r p o r a t i o n
Document
1250_1125-UM100CB-R
Section 7: DMA Page
165
20:16
zero
5'b0
These bits must be zero.
29:21
hdr_size
9'b0
This sets the header length in cache blocks. It sets the number of cache blocks
for which the L2 cacheable attribute will be attached if hdr_cf_en is asserted.
This count is taken from the start of the buffer (the first cache line contains only
32 - offset bytes from the packet).
31:30
reserved
2'b0
Reserved
36:32
zero
5'b0
These bits must be zero.
45:37
asicxfr_size
9'b0
This field sets the size (in cache lines) of the portion of the packet that will be
sent to the ASIC if asic_xfr_en is set. Packets shorter than this size will be sent
in their entirety using the EOP protocol described in
to signal the packet end.
Care must be taken to adjust the number set here when an offset is used
(which must be the case if the pre_addr_en bit is set). The number of cache
lines sent to the ASIC will be:
Offset zero: The number in this field. (If this field is zero then one cache line is
transferred.)
Offset nonzero: One greater than the number in this field.
47:46
reserved
2'b0
Reserved
63:48
int_timeout
16'b0
This field sets the timeout for interrupt generation. See
. If this field is zero then timing of the assertion of the
eop_timer interrupt flag is UNPREDICTABLE.
Table 92: Ethernet and Serial DMA Configuration Register 1
(Cont.)
dma_config1_mac_0_rx_ch_0 -
00_1006_4808
dma_config1_mac_0_tx_ch_0 -
00_1006_4C08
dma_config1_mac_0_rx_ch_1 -
00_1006_4908
dma_config1_mac_0_tx_ch_1 -
00_1006_4D08
dma_config1_mac_1_rx_ch_0 -
00_1006_5808
dma_config1_mac_1_tx_ch_0 -
00_1006_5C08
dma_config1_mac_1_rx_ch_1 -
00_1006_5908
dma_config1_mac_1_tx_ch_1 -
00_1006_5D08
dma_config1_mac_2_rx_ch_0 -
00_1006_6808
dma_config1_mac_2_tx_ch_0 -
00_1006_6C08
dma_config1_mac_2_rx_ch_1 -
00_1006_6908
dma_config1_mac_2_tx_ch_1 -
00_1006_6D08
dma_config1_ser_0_rx -
00_1006_0408
dma_config1_ser_0_tx -
00_1006_0488
dma_config1_ser_1_rx -
00_1006_0808
dma_config1_ser_1_tx -
00_1006_0888
Bits
Name
Default
Description