Hi All, Of late I've spent some time wrestling with mac_scsi. I've made some progress, but I'm uncertain as to how I should procede -- whatever I do, there will be implications for some other NCR5380 drivers. mac_scsi actually works (once I fixed the enable_irq-before-request_irq bug -- already fixed in various other NCR5380 wrapper drivers ... sigh) but it only works in PIO mode. The PDMA read routine causes a bus error (The Guide to Mac Family Hardware says "if a read or write operation over the SCSI bus is not completed within certain time (different for different machines), the general logic IC asserts a bus error (/BERR) to the CPU.") The driver tries to fall back to PIO mode when that happens. The fall back succeeds only on the powerbook 190 and only if the code was compiled with gcc-3. It just hangs on the PB 150 and Mac II, though PIO works on those machines too when PDMA is disabled. So I think there's a race there somewhere. And PIO doesn't work anywhere once debugging printks are enabled. All of which gives me little confidence in NCR5380.c. (I tested those 3 machines because they have the 3 different kinds of VIA2. Logs can be found here <http://www.telegraphics.com.au/~fthain/mac_scsi_logs/> should anyone want to see them.) There is so much duplication of code for the NCR5380 drivers -- sun3, atari, g_NCR5380, 2.4 & 2.2 branches in the mac68k CVS -- that I don't know where to start looking for fixes. Thinking that the bug would be trivial, I started out writing cleanup patches for the existing mac_scsi.c/NCR5380.c combination. But the more I think about it, the less I want to go in that direction. Now I'm thinking that mac_scsi should adopt the atari core, since that appears to be the better maintained contender. Michael, does that sound sensible? Does it have working PDMA? Another thing, should we look at merging sun3_NCR5380.c and atari_NCR5380.c? The diff is huge, but that is because of the code style and formatting cleanups in atari_NCR5380.c. The functional differencess are few and far between. If we can get to a working, common sun3/atari/mac core, I could then look at minimising C preprocessor abuse in favour of a cleaner link-time/ops struct abstraction layer -- with some assistance from Micheal and Sam: I'm assuming that there is a cut somewhere that would make for a broadly useful interface. Does this make sense? Merging core 5380 drivers could _maybe_ go further if those responsible for them were interested, but I would not want to bite off more than atari/mac/sun3 at first. As to the rest, here's a list of all the relevant #includes (this really needs to be converted to a graphical representation somehow..) I don't know who maintains all of these 5380 drivers. files that include NCR5380.c -- ./drivers/scsi/arm/cumana_1.c ./drivers/scsi/arm/oak.c ./drivers/scsi/dmx3191d.c ./drivers/scsi/dtc.c ./drivers/scsi/g_NCR5380.c ./drivers/scsi/mac_scsi.c ./drivers/scsi/pas16.c ./drivers/scsi/t128.c files that include NCR5380.h -- ./drivers/scsi/arm/cumana_1.c ./drivers/scsi/arm/oak.c ./drivers/scsi/atari_scsi.c ./drivers/scsi/dmx3191d.c ./drivers/scsi/dtc.c ./drivers/scsi/g_NCR5380.c ./drivers/scsi/mac_scsi.c ./drivers/scsi/pas16.c ./drivers/scsi/sun3_scsi.c ./drivers/scsi/sun3_scsi_vme.c ./drivers/scsi/t128.c files that include atari_NCR5380.c -- ./drivers/scsi/atari_scsi.c files that include atari_scsi.h -- ./drivers/scsi/atari_scsi.c files that include dtc.h -- ./drivers/scsi/dtc.c files that include g_NCR5380.c -- ./drivers/scsi/g_NCR5380_mmio.c files that include g_NCR5380.h -- ./drivers/scsi/g_NCR5380.c files that include mac_scsi.h -- ./drivers/scsi/mac_scsi.c files that include pas16.h -- ./drivers/scsi/pas16.c files that include sun3_NCR5380.c -- ./drivers/scsi/sun3_scsi.c ./drivers/scsi/sun3_scsi_vme.c files that include sun3_scsi.h -- ./drivers/scsi/sun3_scsi.c ./drivers/scsi/sun3_scsi_vme.c files that include t128.h -- ./drivers/scsi/t128.c Note that this include graph is post-patching: I moved the #include "NCR5380.h" out of sun3_scsi.h and into sun3_scsi.c and sun3_scsi_vme.c so that the graph was more shallow and more symmetrical (that patch is at <http://www.telegraphics.com.au/~fthain/patches_wip/> I'll send some of these patches for the 2.6.28 merge window.) Regards, Finn -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
