Re: pdc202xx_old serious bug with DMA on 2.6.x series

["Adolfo González Blázquez" <agblazquez_mailing@telefonica.net>]

Well, it seems that problem is solved! I'm now using 2.6.7 without
problems. Got same perfomance on hard disks as with 2.4.x series.

Disabling LBA48 for pdc20265 just made it work. This is the simple patch
I applied:

diff --unified --recursive --new-file
linux-2.6.7/drivers/ide/pci/pdc202xx_old.c
linux/drivers/ide/pci/pdc202xx_old.c
--- linux-2.6.7/drivers/ide/pci/pdc202xx_old.c  2004-06-16
07:20:17.000000000 +0200
+++ linux/drivers/ide/pci/pdc202xx_old.c        2004-06-21
02:53:33.000000000 +0200
@@ -721,6 +721,10 @@
        hwif->tuneproc  = &config_chipset_for_pio;
        hwif->quirkproc = &pdc202xx_quirkproc;

+       /* This was present on 2.6.0-test4, maybe here is the bug */
+       if (hwif->pci_dev->device == PCI_DEVICE_ID_PROMISE_20265)
+               hwif->no_lba48 = (hwif->channel) ? 0 : 1;
+
        if (hwif->pci_dev->device != PCI_DEVICE_ID_PROMISE_20246) {
                hwif->busproc   = &pdc202xx_tristate;
                hwif->resetproc = &pdc202xx_reset;


One example about perfomance: 

fito@soho:~$ uname -a
Linux soho 2.6.7-soho #1 Mon Jun 21 03:01:22 CEST 2004 i686 GNU/Linux
fito@soho:~$ time cp /win/Backup/Linux\
Downloads/Isos/yarrow-i386-disc3.iso .

real    0m36.771s
user    0m0.166s
sys     0m9.635s

fito@soho:~$ uname -a
Linux soho 2.4.25-soho #1 jue mar 18 16:30:49 CET 2004 i686 GNU/Linux
fito@soho:~$ time cp /win/Backup/Linux\
Downloads/Isos/yarrow-i386-disc3.iso .

real    0m41.789s
user    0m0.240s
sys     0m7.230s


Hope this patch help!!

Adolfo González Blázquez

PD: I know this is not the "standard" way to send patches, but i'm new
to linux and don't now the correct way...


El dom, 20-06-2004 a las 02:47, Bartlomiej Zolnierkiewicz escribió:
> On Sunday 20 of June 2004 01:00, Adolfo González Blázquez wrote:
> > Hi,
> >
> > Sorry for the delay... I tried 2.5.50 and 2.5.75, and, at least for my
> > machine, everything seems to be perfect. Then i tried every 2.6 kernel.
> > All of them have the same buggy behaviour.
> 
> First of all thanks for doing this.
> 
> > These are the differences between 2.5.75 and 2.6.0 pdc202xx_old.c (sorry
> > if this is not the correct format, im new here :)
> >
> > Hope this will help.
> >
> > Adolfo González
> >
> > ###################################################################
> >
> > --- linux-2.5.75/drivers/ide/pci/pdc202xx_old.c	2003-07-10
> > 22:15:03.000000000 +0200
> > +++ linux-2.6.0/drivers/ide/pci/pdc202xx_old.c	2003-12-18
> > 03:59:53.000000000 +0100
> > @@ -46,7 +46,6 @@
> >  #include <asm/io.h>
> >  #include <asm/irq.h>
> >
> > -#include "ide_modes.h"
> >  #include "pdc202xx_old.h"
> >
> >  #define PDC202_DEBUG_CABLE	0
> > @@ -519,13 +518,15 @@
> >  		} else {
> >  			goto fast_ata_pio;
> >  		}
> > +		return hwif->ide_dma_on(drive);
> >  	} else if ((id->capability & 8) || (id->field_valid & 2)) {
> >  fast_ata_pio:
> >  no_dma_set:
> >  		hwif->tuneproc(drive, 5);
> >  		return hwif->ide_dma_off_quietly(drive);
> >  	}
> > -	return hwif->ide_dma_on(drive);
> > +	/* IORDY not supported */
> > +	return 0;
> >  }
> >
> >  static int pdc202xx_quirkproc (ide_drive_t *drive)
> > @@ -749,9 +750,6 @@
> >  	hwif->tuneproc  = &config_chipset_for_pio;
> >  	hwif->quirkproc = &pdc202xx_quirkproc;
> >
> > -	if (hwif->pci_dev->device == PCI_DEVICE_ID_PROMISE_20265)
> > -		hwif->addressing = (hwif->channel) ? 0 : 1;
> > -
> >  	if (hwif->pci_dev->device != PCI_DEVICE_ID_PROMISE_20246) {
> >  		hwif->busproc   = &pdc202xx_tristate;
> >  		hwif->resetproc = &pdc202xx_reset;
> 
> In 2.6.0-test5 kernel we allowed LBA48 for PDC20265
> (after few people reported that it works okay now)
> but the same patch is also in 2.4 kernels.
> 
> There is one important 2.4 vs 2.6 difference here
> - in 2.6 if the drive is using LBA48 we allow up
> to 1024KiB large requests (you can check if this is
> a problem by replacing "65536" by "256" in ide-probe.c).
> 
> The other likely candidate for breakage is kernel
> 2.6.0-test2 which contains DMA timeout fixes.
> 
> I can make some patches later in the meantime
> somebody may test 2.6.0-test[1,2,4,5].
> 
> Cheers.
> 
> > @@ -928,7 +926,7 @@
> >  	return 0;
> >  }
> >
> > -static struct pci_device_id pdc202xx_pci_tbl[] __devinitdata = {
> > +static struct pci_device_id pdc202xx_pci_tbl[] = {
> >  	{ PCI_VENDOR_ID_PROMISE, PCI_DEVICE_ID_PROMISE_20246, PCI_ANY_ID,
> > PCI_ANY_ID, 0, 0, 0},
> >  	{ PCI_VENDOR_ID_PROMISE, PCI_DEVICE_ID_PROMISE_20262, PCI_ANY_ID,
> > PCI_ANY_ID, 0, 0, 1},
> >  	{ PCI_VENDOR_ID_PROMISE, PCI_DEVICE_ID_PROMISE_20263, PCI_ANY_ID,
> > PCI_ANY_ID, 0, 0, 2},
> >
> > ###################################################################
> >
> > El sáb, 19-06-2004 a las 18:46, Bartlomiej Zolnierkiewicz escribió:
> > > Hi,
> > >
> > > Any news about this issue?
> > >
> > > On Tuesday 15 of June 2004 13:33, you wrote:
> > > > El mar, 15-06-2004 a las 13:15, Marcelo Tosatti escribió:
> > > > > On Tue, Jun 15, 2004 at 01:20:03AM +0200, Adolfo González Blázquez wrote:
> > > > > > El mar, 15-06-2004 a las 01:18, Bartlomiej Zolnierkiewicz escribió:
> > > > > > > On Tuesday 15 of June 2004 00:50, Adolfo González Blázquez wrote:
> > > > > > > > Hi!
> > > > > > >
> > > > > > > Hi,
> > > > > > >
> > > > > > > > Lot of users are reporting seriour problems with pdc202xx_old
> > > > > > > > ide pci driver. Enabling DMA on any device related with this
> > > > > > > > driver makes the system unusable.
> > > > > > > >
> > > > > > > > This seems to happen in all the 2.6.x kernel series.
> > > > > > >
> > > > > > > Doing binary search on 2.4->2.6 kernels would help greatly
> > > > > > > (narrowing problem to a specific kernel versions).
> > > > > >
> > > > > > If it helps, I tried 2.6.2, 2.6.4, 2.6.5, and 2.6.7-rc3, and all
> > > > > > have the bug.
> > > > >
> > > > > And which kernels does not exhibit the problem?
> > > >
> > > > The 2.4 series it's ok, I'm gonna try with different 2.5.x kernels to
> > > > see if i can discover when the bug was introduced
>