RE: [PATCH] [SCSI] LIBSAS: fix libsas link error issue

Xiangliang Yu
2011-06-16T01:58:36Z

>> I get the issue like this:
>> 1. HBA support 3Gbps, level 1 expander support 6Gbps, and level 2 expander
>> support 6Gbps;
>> 2. level 1 is fine, and find that level 2 link rate is 6Gbps in DISCOVER
command
>> response.
>> 3. LIBSAS think level 2 is 6Gbps by sas_ex_get_linkrate function, and send
>> command to level 2 expander
>> 4. LIBSAS link error.
>>
>[Jack Wang]
>What do you mean by "LIBSAS link error", OPEN_REJECT(CONNECTION RATE NOT
>SUPPORTED)? LIBSAS only get the error event through LLDD.
>According to SAS2r15 7.8.3
I mean that HBA get link error. Sorry.

>A SAS initiator port shall set the initial CONNECTION RATE field to:
>a) the highest supported connection rate supported by a potential pathway as
determined during the
>discover process (e.g., based on the logical link rates of each logical link
reported in the SMP
>DISCOVER responses); or
Sas_ex_get_linkrate function

>b) the logical link rate of the logical phy used to transmit the OPEN
address frame.
MVSAS get value of linkrate from sas_ex_get_linkrate function(child->linkrate)

>If a SAS initiator port selected a connection rate based on discover process
information but the connection
>request results in OPEN_REJECT (CONNECTION RATE NOT SUPPORTED), then the
discover process
>information is no longer current and the discover process should be run
again.

Fail again.