
Philips Semiconductors
PNX15xx Series
Volume 1 of 1
Chapter 3: System On Chip Resources
PNX15XX_SER_3
Koninklijke Philips Electronics N.V. 2006. All rights reserved.
Product data sheet
Rev. 3 — 17 March 2006
3-3
Remark: Partial 32-bit load or stores from a PCI master to an MMIO register is not
supported. Therefore byte of 16-bit half-word accesses are not supported.
2.2 The CPU View
The TM3260 CPU supports three different apertures:
the MMIO aperture, used to access all the internal PNX15xx Series registers.
Remark: To ensure backward compatibility with future devices, writes to any
undefined or reserved MMIO bit should be ‘0’, and reads should be ignored. This rules
applies to ALL the modules of PNX15xx Series.
the DRAM aperture, used to access the main memory of PNX15xx Series which
contains the instruction and the data for TM3260 and data used by other PCI
masters.
the APERT1 aperture, used by TM3260 to access low speed slave devices like
Flash memories or IDE disk drives that are located in the XIO aperture or any
other PCI slave.
TM3260 CPU accesses the three apertures using regular load/store operations.
Some internal logic in the data cache unit surveys the load/store addresses and
routes the request to the appropriate internal PNX15xx Series registers (this includes
the registers belonging to TM3260) if the address falls into the MMIO aperture. If the
load/store address falls into the DRAM aperture the load/store request is routed to
the data cache and eventually the main memory. Finally if the load/store address falls
into the APERT1 aperture, the request is send to the PCI bus (if it maps to an XIO
device or a PCI internal aperture, see the following
Section 2.3).Figure 2 presents the memory map seen by the TM3260 and the remaining of the
PNX15xx Series system. The apertures can be placed in any order with respect to
each other.
PNX15xx Series allows a host CPU to prevent TM3260 to change its own aperture
registers. This can be obtained by ipping
locations are dened as follows:
The MMIO aperture is starting at the address contained in the BASE_14 MMIO
register. The register is located and owned by the PCI module. It is equivalent to
the BASE_14 PCI Conguration space register. This is different with respect to
PNX1300 Series or PNX1300 Series where an MMIO_BASE MMIO register was
available.
The DRAM aperture is starting at the address contained in the TM32_DRAM_LO
MMIO register and nishes at TM32_DRAM_HI - 1.
Remark: If the value 0x0000,0000 is stored into TM32_DRAM_HI, this value is
understood as 0x1,0000,0000.
The APERT1 aperture is starting at the address contained in the
TM32_APERT1_LO MMIO register and nishes at TM32_APERT1_HI - 1.