mpc823rg Freescale Semiconductor, Inc, mpc823rg Datasheet - Page 266

• Manufacturer Part Number: mpc823rg
• Description: Mpc823 Powerquicc Integrated Communications Processor For Portable Systems
• Manufacturer: Freescale Semiconductor, Inc

11.8 MANIPULATING THE TRANSLATION LOOKASIDE BUFFER
11.8.1 Reloading the Translation Lookaside Buffer
The TLB reload (tablewalk) function is performed in the software with optional hardware
assistance in the following ways:
• Automatically stores the missed effective data or instruction address and default
• Automatically updates the replacement location counter to point to the entry to be
• Generates a level one pointer when a mfspr Rx, M_TWB is performed by the
• Generates a level two pointer when a mfspr Rx, MD_TWC is performed by the
• Performs a write to the TLB entry by loading the tablewalk level two entry value to the
• A special register (M_TW) is available for the software tablewalk routine, in addition to
attributes in the MI_EPN or MD_EPN registers, respectively. This value is loaded into
the selected entry on a write to MI_RPN or MD_RPN for the instruction and data
translation lookaside buffer.
replaced. This value is placed in the xTLB_INDX field of the MI_CTR and MD_CTR.
concatenation of the level one table base and level one index. See Figure 11-2 and
Figure 11-3 for details.
concatenation of the level two table base and level two index.
MI_RPN or MD_RPN register.
the PowerPC architecture’s special registers (SPRG0–SPRG3). Using this register
allows for more efficient interrupt handling.
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Memory Management Unit
11-49