Intel
®
81341 and 81342 I/O Processors
December 2007
Developer’s Manual
Order Number: 315037-002US
695
SRAM Memory Controller—Intel
®
81341 and 81342
8.4
ECC Interrupts/Error Conditions
The SMCU has two ECC conditions which require intervention from the Intel XScale
®
processor. If a single-bit error is detected during a read cycle, the SMCU can correct
the data returned but software needs to fix the error in the memory array. If a multi-bit
error is detected, the core decides how to handle the condition. For all ECC errors, the
SMCU records the requester of the transaction resulting in the error in SELOG[23:16]
and interrupts the core.
If the SMCU detects an ECC error during a read or write cycle, SMCISR[0] is set to 1.
Whenever the SMCU toggles the SMCISR[0] bit from 0 to 1, an interrupt is generated
to the core.
shows how the SMCU responds to error conditions.
Note:
If ECC reporting is enabled with SECCR[1] or SECCR[0] and an ECC error occurs,
SMCISR[0] is set and SELOG/SECAR/SECUAR logs the error in addition to
actions.
Table 418. SMCU Error Response
Error Type
SMCU Action
Single-Bit during a read or write
Fix Error (if ECC error correction enabled in the SECCR)
Multi-bit during a read
Target Abort the Internal Bus transaction
Multi-bit during a write
New ECC is generated with bad data and written to SRAM array. Data
location is no longer valid.