CVS commit: src/sys/arch/mac68k/obio

["Rin Okuyama" <rin%netbsd.org@localhost>]

Module Name:    src
Committed By:   rin
Date:           Mon Feb 22 05:23:37 UTC 2021

Modified Files:
        src/sys/arch/mac68k/obio: esp.c

Log Message:
Elucidate why synchronous transfer is disabled for AV Macs.

Sync negotiation times out when drive advertises that capability:

----
sd1 at scsibus0 target 1 lun 0: <codesrc, SCSI2SD, 6.0> disk fixed
sd1: 16384 MB, 2088 cyl, 255 head, 63 sec, 512 bytes/sect x 33554432 sectors
sd1: sync (160.00ns offset 15), 8-bit (6.250MB/s) transfers
...
sd1(esp0:0:1:0): esp0: timed out [ecb 0x9f7fc4 (flags 0x1, dleft 8, stat 0)], <state 5, nexus 0x9f7fc4, phase(l 1, c 1, p 1), resid 8, msg(q 0,o 80) DMA active>
sd1(esp0:0:1:0): sync negotiation disabled
sd1(esp0:0:1:0): esp0: timed out [ecb 0x9f7fc4 (flags 0x41, dleft 8, stat 0)], <state 5, nexus 0x9f7fc4, phase(l 1, c 1, p 1), resid 8, msg(q 20,o 80) DMA active> AGAIN
sd1: async, 8-bit transfers
----

This is observed for real SCSI drives as well as SCSI2SD (rev 6.0).

Note that this is not a fallout from DMA patch for AV Macs; timeout
takes place even if ``avdma'' code is forcibly disabled.

No binary changes.


To generate a diff of this commit:
cvs rdiff -u -r1.59 -r1.60 src/sys/arch/mac68k/obio/esp.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.