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Zynq-7000 AP SoC Technical Reference Manual www.xilinx.com 743
UG585 (v1.11) September 27, 2016
Chapter 29: On-Chip Memory (OCM)
SLVERR response can also be issued to the requesting master for devices that are unable to or prefer
not to handle interrupts.
29.3 Register Overview
A partial list of registers related to the OCM is listed in Table 29-7. (See Appendix B, Register Details
for the complete list.)
29.4 Programming Model
29.4.1 Changing Address Mapping
A method for reorganizing the OCM address space and performing DDR remapping is as follows:
1. Complete all outstanding transactions by issuing data (DSB) and instruction (ISB)
synchronization barrier commands.
2. Since the changing the address map may prevent the fetching of the nearby instructions, enable
L1 instruction cache, and prefetch cache lines for the remainder of the function, typically with PLI
instructions.
3. To facilitate prefetching, consider aligning the instructions to be prefetched to start at a
cacheline boundary.
4. Ensure that the instruction prefetching has completed by issuing an ISB instruction.
Table 29-7: On-Chip Memory Register Overview
Module Register Name Overview
OCM OCM_PARITY_ERRADDRESS Returns RAM parity error address
OCM_PARITY_CTRL Set interrupt enables, AXI read response error enable,
parity enable, odd parity generation
OCM_IRQ_STS Read raw interrupt status, clear interrupts
OCM_CONTROL Change pre-arbitration priority
slcr SLCR_LOCK SLCR register write disable
SLCR_UNLOCK SLCR register write enable
OCM_RST_CTRL OCM subsystem reset
TZ_OCM_RAM0/1 OCM TrustZone
OCM_CFG Configures RAM address mapping
mpcore SCU_CONTROL_REGISTER SCU address filtering enable
Filtering_Start_Address_Register SCU address filtering base address
Filtering_End_Address_Register SCU address filtering end address