3 ecc/parity mode, Ecc/parity mode -4, External l2 cache in write-through mode -4 – Freescale Semiconductor MPC8260 User Manual

Page 528

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Secondary (L2) Cache Support

MPC8260 PowerQUICC II Family Reference Manual, Rev. 2

12-4

Freescale Semiconductor

Figure 12-2. External L2 Cache in Write-Through Mode

12.1.3

ECC/Parity Mode

ECC/parity mode is a subset of write-through mode with some connection changes that allow the L2 cache
to support ECC or Parity. The connection changes are:

The PowerQUICC II’s DP[0:7] signals are connected to the L2 cache’s DP[0:7] signals.

The L2’s TSIZ[0:2] signals are pulled down to always indicate 8-byte transaction size.

The L2’s A[29:31] signals are pulled down.

BR

DBG

TS, TT[0:4], TBST, TSIZ[1–3]

A[0–31]

CI, GBL, TA, DBB, TEA

CPU_BR, CPU_BG, CPU_DBG

D[0–63]

PowerQUICC II

L2BR

L2DBG

TS, TT[0–4], TBST, TSIZ[0–2]

CI, GBL, TA, DBB, TEA

AACK, ARTRY

AACK, ARTRY

CPU_BR,CPU_BG,CPU_DBG

L2_CLAIM

L2_HIT

A[0–31]

D[0–63]

Memory Controller

SDRAM Main Memory

Latch

MUX

I/O Devices

MPC2605

BG

L2BG

TSIZ[0]

(pull down)

WT

(pull down)

(pull up)

(pull up)

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