DS711 Datasheet, PDF (17/42 Pages) Xilinx, Inc – LogiCORE IP PLBV46 to AXI

LogiCORE IP PLBV46 to AXI Bridge (v2.01.a)
For the AXI slaves having a mixed address space for registers and memory require byte swapping for the memory
address regions and do not require the byte swapping for register address regions. To address this, the parameter
C_NBS_NUM_ADDR_RNGS must be set based on the number of no byte swap address regions in the given
address space. The corresponding no byte swap region base and high addresses must be set to the parameters
C_NBS_RNGx_BASEADDR and C_NBS_RNGx_HIGHADDR.
Though the parameter C_EN_BYTESWAP is ‘1’ for the transactions in these no byte swap address ranges, the byte
swapping is not applicable. When C_EN_BYTE_SWAP=0 for the entire address space irrespective of
C_NBS_NUM_ADDR_RNGS, byte swapping is not applicable.
The following Table 4 shows the data bits swap and Table 5 shows byte enables swap from PLB to AXI for different
values of C_EN_BYTE_SWAP when C_NBS_NUM_ADDR_RNGS=0.
When C_EN_BYTE_SWAP=1 and C_NBS_NUM_ADDR_RNGS/=0, then the data transactions in
C_NBS_RNGx_BASEADDR and C_NBS_RNGx_HIGHADDR regions are same as given in Table 4 and Table 5
when C_EN_BYTE_SWAP=0.
.
Table 4: Data bits swap from PLB to AXI when C_SPLB_NATIVE_DWIDTH = 32
PLB data bits AXI data bits when C_EN_BYTE_SWAP = 1 AXI data bits when C_EN_BYTE_SWAP = 0
D0 - D7
D7 - D0
D31 - D24
D8 - D15
D15 - D8
D23 - D16
D16- D23
D23 - D16
D15 - D8
D24 - D31
D31 - D24
D7 - D0
Table 5: Byte enables swap from PLB to write strobes on AXI when C_SPLB_NATIVE_DWIDTH = 32
PLB byte AXI write strobes when
enables C_EN_BYTE_SWAP = 1
AXI write strobes when
C_EN_BYTE_SWAP = 0
BE0
WSTRB0
WSTRB3
BE1
WSTRB1
WSTRB2
BE2
WSTRB2
WSTRB1
BE3
WSTRB3
WSTRB0
X-Ref Target - Figure 2
0," SIDEBIGENDIAN BITWORD
.ISBYTEADDRESSOFFSET




0," SIDEBIGENDIAN BITENABLE
 




 
!8) SIDELITTLEENDIAN BITWORD
.ISBYTEADDRESSOFFSET
!8) SIDELITTLEENDIAN BIT7342"
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Figure 2: Byte Data Swap and WrSTRB Swap to BEs as Data Traverses the PLBV46 to AXI Bridge
DS711 July 25, 2012
www.xilinx.com
17
Product Specification