On Thu, 31 Oct 2024, Magnus Lindholm wrote: > > I think Thomas will be unhappy about disabling DAC completely for the > > 1040: as I infer from his response it is indeed required for his Octane to > > operate correctly, and which also presumably implies he does have revision > > C of the chip to verify your fix with. Thomas? > > > >From the Tsunami paper: > > "The DMA monster window is enabled by PCTL<MWIN>. If enabled, this > window lies from 100.0000.0000 to > 100.FFFF.FFFF, which requires a dual-address cycle (DAC) access from > the PCI bus. This window maps to system memory as defined in Section > 10.1.4" > > When I run the qla1280.c driver with some debugging enabled I see this > output after a while: > > es40 kernel: S/G Segment Cont. phys_addr=100 7fff8000, len=0x10000 > es40 kernel: S/G Segment Cont. phys_addr=100 80008000, len=0x10000 > es40 kernel: S/G Segment Cont. phys_addr=100 8011e000, len=0x10000 > > Right after the above messages in log files I see failed read/writes > on the drive attached to the qla1040B. So as soon as I hit the > "monster window" in DMA-addressing my files get messed up. I guess > this never happens if I don't have enough memory in the system, or if > I set the DMA_BIT_MASK. I'll try to enable some more debug logs from > DMA and IOMMU stuff. So it is as I expected. Please do coordinate with Thomas and implement the DMA mask on a per-revision basis as I suggested. > > > Which is consistent with how NetBSD does things in their ISP driver. > > > Also, in this case the HWMSK actually works for filtering out the > > > hardware revision part of the CFG0 register, since it would actually > > > require a 6-bit mask to match the current definitions in qla1280.c, > > > right? > > > > Thanks! I guess changing these definitions in the header file should > be safe, I don't think they are really used anywhere in the code as of > now. Would make a patch for reporting on the hardware revisions of > 1040/1020 more consistent with the headers. Well ISP_CFG0_1040A does get used as I also noted. I do hope Christoph chimes in on the erratum concerned. Maciej
