DMA issues with FC4 on a Dell precision M70

[Alfredo Ferrari]

Yes

my PATA disk is the master on the second IDE channel (hdc). This is 
actually the laptop modular bay where I can insert the DVD/2nd hard 
drive/2nd battery. The same disk in the same bay on the same channel
of a D800 (where the primary disk is PATA and not SATA as in the M70)
works nicley with DMA enabled at boot time.

Unfortunately it seems to be a known Linux kernel bug/limitation (see 
https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=163418 )
a rather frustrating one I must say.

                    Thanks for the help

                       Alfredo

On Sat, 18 Feb 2006, Alessandro Brezzi wrote:

> 2006/2/18, Alfredo Ferrari <list at pceet030.cern.ch>:
>>
>> Hi
>>
>> I have a Dell Precision M70 whose primary hard disk is a SATA disk
>> (/dev/sda) running FC4 (kernel 2.6.15-1.1831_FC4).
>> The secondary hard disk is a PATA one (/dev/hdc, in the laptop modular
>> bay) and apparently I cannot get DMA enabled on it, resulting in very poor
>> performances (2.5 MB/s against 25 MB/s for the same disk in the modular
>> bay of a PATA only Dell D800 where it runs happily with DMA enabled).
>>
>> If I try to enable DMA by hand I get:
>>
>> [root at pcalfr ~]# hdparm -d1 /dev/hdc
>>
>> /dev/hdc:
>>   setting using_dma to 1 (on)
>>   HDIO_SET_DMA failed: Operation not permitted
>>   using_dma    =  0 (off)
>>
>> Every help/suggestion is greatly appreciated
>>
>>               Alfredo Ferrari
>>
>> P.S. The only messages of some relevance I can see at boot (from dmesg)
>> are:
>>
>>    DMA zone: 4096 pages, LIFO batch:0
>>    DMA32 zone: 0 pages, LIFO batch:0
>>    Normal zone: 225280 pages, LIFO batch:31
>>    HighMem zone: 294872 pages, LIFO batch:31
>>
>> ...
>>
>> PCI: Ignoring BAR0-3 of IDE controller 0000:00:1f.2
>>
>> ...
>>
>> Uniform Multi-Platform E-IDE driver Revision: 7.00alpha2
>> ide: Assuming 33MHz system bus speed for PIO modes; override with
>> idebus=xx
>> ide0: I/O resource 0x1F0-0x1F7 not free.
>> ide0: ports already in use, skipping probe
>> Probing IDE interface ide1...
>> hdc: ST94811A, ATA DISK drive
>> ide1 at 0x170-0x177,0x376 on irq 15
>> hdc: max request size: 1024KiB
>> hdc: 78140160 sectors (40007 MB) w/8192KiB Cache, CHS=16383/255/63
>> hdc: cache flushes supported
>>   hdc: hdc1 hdc2 hdc3 < hdc5 hdc6 hdc7 hdc8 >
>> ide-floppy driver 0.99.newide
>>
>> ...
>>
>> SCSI subsystem initialized
>> libata version 1.20 loaded.
>> ata_piix 0000:00:1f.2: version 1.05
>> ACPI: PCI Interrupt 0000:00:1f.2[B] -> Link [LNKB] -> GSI 5 (level, low)
>> -> IRQ 5
>> ata: 0x170 IDE port busy
>> PCI: Setting latency timer of device 0000:00:1f.2 to 64
>> ata1: SATA max UDMA/133 cmd 0x1F0 ctl 0x3F6 bmdma 0xBFA0 irq 14
>> ata1: dev 0 cfg 49:0f00 82:746b 83:7fe9 84:4023 85:7469 86:3e49 87:4023
>> 88:203f
>> ata1: dev 0 ATA-6, max UDMA/100, 195371568 sectors: LBA48
>> ata1(0): applying bridge limits
>> ata1: dev 0 configured for UDMA/100
>> scsi0 : ata_piix
>>    Vendor: ATA       Model: Hitachi HTS72101  Rev: MCZO
>>    Type:   Direct-Access                      ANSI SCSI revision: 05
>> SCSI device sda: 195371568 512-byte hdwr sectors (100030 MB)
>> SCSI device sda: drive cache: write back
>> SCSI device sda: 195371568 512-byte hdwr sectors (100030 MB)
>> SCSI device sda: drive cache: write back
>>   sda: sda1 sda2 sda3 sda4 < sda5 sda6 sda7<6>input: PS/2 Mouse as
>> /class/input/input1
>>   sda8 sda9 >
>> sd 0:0:0:0: Attached scsi disk sda
>> input: AlpsPS/2 ALPS GlidePoint as /class/input/input2
>> kjournald starting.  Commit interval 600 seconds
>
>
>
> Hi Alfredo,
> is your PATA disk  attached to the secondary IDE channel? Not sure about
> laptop arch, but in desktop box primary and secondary IDE interface work
> different.
> HTH
>
> --
> Alessandro Brezzi
>

-- 

+----------------------------------------------------------------------------+
|  Alfredo Ferrari                         ||  Tel.: +41.22.767.6119         |
|  C.E.R.N.                                ||  Fax.: +41.22.767.7555         |
|  European Laboratory for Particle Physics||                                |
|  AB Division / ATB Group                 ||  e-mail:                       |
|  1211 Geneva 23                          ||     Alfredo.Ferrari at cern.ch    |
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