Table of Contents
Advertisement
BJ35.
PCIe* Root Port May Not Initiate Link Speed Change
Problem:
PCIe specification rev 2.0 requires the upstream component to maintain the PCIe link
at the target link speed or the highest speed supported by both components on the
link, whichever is lower. PCIe root port will not initiate the link speed change without
being triggered by the software. System BIOS will trigger the link speed change under
normal boot scenarios. However, BIOS is not involved in some scenarios such as link
disable/re-enable or secondary bus reset and therefore the speed change may not
occur unless initiated by the downstream component. This erratum does not affect the
ability of the downstream component to initiate a link speed change. All known 5.0Gb/
s-capable PCIe downstream components have been observed to initiate the link speed
change without relying on the root port to do so.
Implication:
Due to this erratum, the PCIe root port may not initiate a link speed change during
some hardware scenarios causing the PCIe link to operate at a lower than expected
speed. Intel has not observed this erratum with any commercially available platform.
Workaround:
None identified.
Status:
For the steppings affected, see the Summary Tables of Changes.
BJ36.
Incorrect Address Computed For Last Byte of FXSAVE/FXRSTOR or
XSAVE/XRSTOR Image Leads to Partial Memory Update
Problem:
A partial memory state save of the FXSAVE or XSAVE image or a partial memory state
restore of the FXRSTOR or XRSTOR image may occur if a memory address exceeds the
64KB limit while the processor is operating in 16-bit mode or if a memory address
exceeds the 4GB limit while the processor is operating in 32-bit mode.
Implication:
FXSAVE/FXRSTOR or XSAVE/XRSTOR will incur a #GP fault due to the memory limit
violation as expected but the memory state may be only partially saved or restored.
Workaround:
Software should avoid memory accesses that wrap around the respective 16-bit and
32-bit mode memory limits.
Status:
For the steppings affected, see the Summary Tables of Changes.
BJ37.
Performance Monitor SSE Retired Instructions May Return Incorrect
Values
Problem:
Performance Monitoring counter SIMD_INST_RETIRED (Event: C7H) is used to track
retired SSE instructions. Due to this erratum, the processor may also count other types
of instructions resulting in higher than expected values.
Implication:
Performance Monitoring counter SIMD_INST_RETIRED may report count higher than
expected.
Workaround:
None identified.
Status:
For the steppings affected, see the Summary Tables of Changes.
Specification Update
31
Hide quick links:
Advertisement
Table of Contents
