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SubjectRe: [PATCH 3/5] cxl/pci: Discover and cache pointer to RCD dport's CXL RAS registers
Hi Ariel,

On 10/28/22 07:53, wrote:
>> -----Original Message-----
>> From: Terry Bowman <>
>> Sent: Friday, October 21, 2022 3:56 PM
>> To:;;;;
>> Cc:;;;;
>> Subject: [PATCH 3/5] cxl/pci: Discover and cache pointer to RCD dport's CXL RAS registers
>> CXL RAS information resides in a RAS capability structure located in
>> CXL.cache and CXL.mem registers.[1] The RAS capability provides CXL
>> specific error information that can be helpful in debugging. This
>> information is not currently logged but needs to be logged during PCIe AER
>> error handling.
>> Update the CXL driver to find and cache a pointer to the CXL RAS
>> capability. The RAS registers resides in the downport's component register
>> block. Note:RAS registers are not in the upport. The component registers
>> can be found by first using the RCRB to goto the downport. Next, the
>> downport's 64-bit BAR[0] will point to the component register block.
> I realize this patch is for dport only, but regarding "Note:RAS registers
> are not in the upport.", the upstream port also has RAS registers.

Correct. Thanks for pointing this out.

> Per CXL 3.0 Section RCD Upstream Port-detected Errors:
> "1. If a CXL.cache or CXL.mem logic block in UPZ detects a protocol or link
> error, the block shall log the error in the CXL RAS Capability (see Section

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