Freescale Semiconductor PXR4030, Reference Manual

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Peripheral Bridge (PBRIDGE)
Freescale Semiconductor 15-15
PXR40 Microcontroller Reference Manual, Rev. 1
The modules that are on-platform and those that are off-platform are detailed in Table 15-7 .
PBRIDGE occupies a 64 MB portion of the address space. A 0.5 MB portion of this space is allocated to
on-platform peripherals. The remaining 63.5 MB is available for off-platform devices. The register maps
of the slave peripherals are located on 16-KB boundaries. Each slave peripheral is allocated one 16-KB
block of the memory map, and is activated by one of the module enables from the PBRIDGE. Up to
thirty-two 16-KB external slave peripherals can be implemented, occupying contiguous blocks of 16 KB.
Two global external slave module enables are available for the remaining 63 MB of address space to allow
for customization and expansion of addressed peripheral devices. In addition, a single non-global module
enable is also asserted whenever any of the 32 non-global module enables is asserted.
PBRIDGE is responsible for indicating to slave peripherals if an access is in supervisor or user mode. The
PBRIDGE can block user mode accesses to certain slave peripherals or it can allow the individual slave
peripherals to determine if user mode accesses are allowed. In addition, peripherals can be designated as
write-protected. The PBRIDGE supports the notion of trusted masters for security purposes. Masters can
be individually designated as trusted for reads, trusted for writes, or trusted for both reads and writes, as
well as being forced to look as though all accesses from a master are in user mode privilege level.
PBRIDGE also supports buffered writes, allowing write accesses to be terminated on the system bus in a
single clock cycle, and then subsequently performed on the slave interface. Write buffering is controllable
on a per-peripheral basis. The PBRIDGE implements a two-entry 32-bit write buffer.
Table 15-7. On-Platform and Off-Platform Peripherals
On-Platform Off-Platform
Enhanced direct memory access (eDMA) Deserial serial peripheral interface (DSPI)
PBRIDGE A and B Enhanced queued analog-to-digital converter (eQADC)
Interrupt controller (INTC) Enhanced serial communication interface (eSCI)
Error correction status module (ECSM) FlexCAN controller area network
System bus crossbar switch (XBAR) Boot assist module (BAM)
Memory Protection Unit (MPU) System integration unit (SIU)
Software Watchdog Timer (SWT) Enhanced modular input/output subsystem (eMIOS)
System Timer Module (STM) Frequency modulated phase locked loop (FMPLL)
Enhanced time processing unit (eTPU)
External bus interface (EBI)
Flash bus interface unit (FBIU)
FlexRay
Power Management Controller (PMC)
PIT_RTI
Decimation Filters
Temp Sensor