Gaston, Jason D wrote:
>> -----Original Message-----
>> From: Alan Cox [mailto:alan@xxxxxxxxxxxxxxxxxxx]
>> Sent: Monday, October 29, 2007 3:14 PM
>> To: Gaston, Jason D
>> Cc: linux-ide@xxxxxxxxxxxxxxx
>> Subject: Re: ATAPI devices in AHCI mode not working
>>
>>> ata1: SATA max UDMA/133 abar m1024@0xd9101000 port 0xd9101100 irq 216
>>> ata2: SATA max UDMA/133 abar m1024@0xd9101000 port 0xd9101180 irq 216
>>> ata1: SATA link up 1.5 Gbps (SStatus 113 SControl 300)
>>> ata1.00: ATAPI: ATAPI DVD D DH16D2S, EP52, max UDMA/100
>>> ata1.00: configured for UDMA/100
>> Much better - no misdetected link type, no device claiming to be PATA
>> when its SATA.
>>
>>
>> Right that eliminates all the obvious goings on being caused by broken
>> devices which is a start. Doesn't shed any light on the rest of it.
> What
>> happens if you boot with irqpoll enabled ? (wondering if the timeouts
> are
>> ACPI or IRQ routing stuff)
>
> I rebuilt the kernel; the DVD and USB devices are functional now. I'm
> not sure what the problem was before. On a side note: In 2.6.24.rc1 the
> DVD starts working right away, but on a SLES10_SP1 kernel, it takes some
> time for it to step down to a PIO mode before the DVD can be mounted.
> Oh well.
Yeah, there has been quite some update in libata between SLES10_SP1 and
2.6.24-rc1. The controller being ahci, I wonder whether this is caused
by the different in check_atapi_dma().
1. Does other optical drives have the same problem? If not, please post
the result of "hdparm -I /dev/sr0" with the problematic one attached.
2. If you apply the attached patch to 2.6.24-rc1, does it behave the
same as the SLES10SP1 kernel?
--
tejun
diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 8ee56e5..5d9b193 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -4491,11 +4491,13 @@ int ata_check_atapi_dma(struct ata_queued_cmd *qc)
{
struct ata_port *ap = qc->ap;
+#if 0
/* Don't allow DMA if it isn't multiple of 16 bytes. Quite a
* few ATAPI devices choke on such DMA requests.
*/
if (unlikely(qc->nbytes & 15))
return 1;
+#endif
if (ap->ops->check_atapi_dma)
return ap->ops->check_atapi_dma(qc);
