CPC700 User’s Manual—Preliminary
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3.15.7.1 PCI Writes to Local Memory
An error associated with the PCI interface will be logged into the processor interface’s BESR and BEAR
registers. The information associated with the error will be held and locked if the requesting PCI interface’s
lockErr signal is asserted with the request. If the error status is locked, subsequent errors detected by the
60x-PLB slave will not update BESR and BEAR as long as the BESR and BEAR lock bits are set. Software
may clear these bits to enable subsequent error status logging. If the error status is not locked, subsequent
errors detected by the 60x-PLB slave will update (and overwrite) BESR and BEAR.
Memory select error on writes will set M1ET to b’101’ (non-configured bank error), M1RWS to 0, M1FL and
M1AL will be set to 1 (all in the BESR register) if the PCI interface’s lockErr signal is asserted with the
request.
3.15.7.2 PCI Reads From Local Memory
The processor interface does not respond on the PLB for read accesses that target it’s global decode of
<2Gig and result in a memory select error. Specifically, the 60x-PLB slave interface will decode the access
to be below 2Gig, assert PLB_Wait, and forward the request to the memory controller. If the memory con-
troller responds with a memory select error (indicating that physical memory does not exist at the
requested address), the 60x-PLB slave interface will deassert PLB_Wait, allowing the requested transfer to
time-out on the PLB. In this case the PLB arbiter will complete the necessary handshaking to the PCI Inter-
face and assert MErr to it. The PCI interface may respond to this error condition in various ways depending
on how it is programmed. See Section 5.10.3.7, “PLB Master PLB_MErr Detection” for details.
If ECC is enabled and an uncorrectable error is encountered for a PCI read from memory, PLB_MErr will
be asserted for the associated transfer. BESR and BEAR will not be updated. ECC error status will be
updated in the ECC error register.
To enable the processor interface’s PLB slave interface to assert PLB_MErr in response to the above,
ERREN1[4] must be set to 1. Error logging occurs only if ERREN1[4] is set to 1. Default value for
ERREN1[4] is 1 (PLB_MErr assertion enabled).
3.15.8 MCP_REQ ERROR
The MCP_REQ (Machine Check Interrupt) input to the CPC700, when asserted, triggers the assertion of
MCP_N (if MCP_N assertion is enabled via PRIFOPT1[1]) to the local processor. Following are some char-
acteristics of this input:
The MCP_REQ input is double-latched in the processor interface and may be asserted asynchronously.
• There are no internal registers associated with MCP_REQ. The external logic that asserts MCP_REQ
to CPC700 must provide mask and status information.
• The MCP_REQ input contains no edge detection logic. The CPC700 has no memory of any previous
state of MCP_REQ.
• In general, the assertion of MCP_REQ has no effect on any other processes in the CPC700.
MCP_N is generally asserted continuously while MCP_REQ is sampled valid; however, If an error was
detected before the MCP_REQ was detected, then the error handling logic will not sample the MCP_REQ
input (and thus not detect it) until the previous error is cleared using the appropriate register.
• If MCP_REQ is deasserted before the previous error is cleared, the MCP_REQ will be lost.
• if MCP_REQ is still asserted when the previous error is cleared, then MCP_REQ will be sampled
asserted and MCP_N will begin to be asserted.
Содержание CPC700
Страница 1: ...CPC700 Memory Controller and PCI Bridge User s Manual Version 1 1 Issue Date 3 22 00 Preliminary...
Страница 10: ...Table of Contents x Table of Contents...
Страница 16: ...Tables xvi List of Tables...
Страница 28: ...1 12 CPC700 User s Manual Preliminary...
Страница 72: ...3 36 Processor Interface...
Страница 132: ...4 60 Memory Controller...
Страница 184: ...5 52 PCI Interface...
Страница 194: ...6 10 Clock Power Management and Reset...
Страница 224: ...8 18 IIC...
Страница 244: ...10 10 Interrupt Controller...
Страница 246: ...I 11 2 JTAG...
Страница 250: ...12 4 Processor Local Bus PLB...
Страница 262: ...14 10 Register Summary...
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