ata_piix on MacBook4,1: CD/DVD drive often fails to work

["MATSUBAYASHI, 'Shaolin' Kohji" <shaolin@rhythmaning.org>]

[-- Attachment #1: Type: text/plain, Size: 3019 bytes --]

Hi,

It happens very often on my MacBook4,1 (still running with i686 kernel
for a certain personal reason, not x86_64 though) that the machine
slows down, gnome CD player suddenly opens (even though there is no CD
media loaded into the drive), and touchpad don't work nicely.

  irq 21: nobody cared (try booting with the "irqpoll" option)
  Disabling IRQ #21


In such a situation, dmesg always shows the following messages
every two seconds which slows down the machine so bad and annoying:

  hda: status error: status=0x59 { DriveReady SeekComplete DataRequest Error }
  hda: status error: error=0x40 { LastFailedSense=0x04 }
  ide: failed opcode was: unknown
  hda: drive not ready for command


Removing ide-cd_mod kernel module would help stopping these
repeating messages though.


The IDE (PATA) controller attached with the CD/DVD drive is:

00:1f.1 IDE interface [0101]: Intel Corporation 82801HBM/HEM (ICH8M/ICH8M-E) IDE Controller [8086:2850] (rev 03) (prog-if 8f [Master SecP SecO PriP PriO])
        Subsystem: Apple Computer Inc. Unknown device [106b:00a1]
        Control: I/O+ Mem- BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B-
        Status: Cap- 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR-
        Latency: 0
        Interrupt: pin A routed to IRQ 21
        Region 0: I/O ports at 6108 [size=8]
        Region 1: I/O ports at 6124 [size=4]
        Region 2: I/O ports at 6100 [size=8]
        Region 3: I/O ports at 6120 [size=4]
        Region 4: I/O ports at 60e0 [size=16]


/proc/interrupts shows like this:

           CPU0       CPU1       
  0:     149053     159890   IO-APIC-edge      timer
  8:          0          3   IO-APIC-edge      rtc
  9:      21652       1462   IO-APIC-fasteoi   acpi
 16:      96958     103303   IO-APIC-fasteoi   uhci_hcd:usb2, uhci_hcd:usb3, i915@pci:0000:00:02.0
 17:      10238         17   IO-APIC-fasteoi   eth0
 18:      75785       3642   IO-APIC-fasteoi   ata_piix, uhci_hcd:usb5
 19:          2          0   IO-APIC-fasteoi   ohci1394
 20:         98         97   IO-APIC-fasteoi   uhci_hcd:usb1, ehci_hcd:usb6, HDA Intel
 21:      39926      36169   IO-APIC-fasteoi   ide0, ehci_hcd:usb4, uhci_hcd:usb7
NMI:          0          0   Non-maskable interrupts
LOC:     505228     495166   Local timer interrupts
RES:     115346     108647   Rescheduling interrupts
CAL:        110      14262   function call interrupts
TLB:        182        184   TLB shootdowns
TRM:          0          0   Thermal event interrupts
SPU:          0          0   Spurious interrupts
ERR:          0
MIS:          0


Then the following patch fixed the problem anyhow at least on my machine
(I suspect changing from ich_pata_100 to ich_pata_66, especially
removing the flag PIIX_FLAG_CHECKINTR, did something good in this case).

I am not certain whether this patch is the right/correct solution
for that, but anyway here's it. Let me know if there's something
I can do for debugging further.

--
Kohji


[-- Attachment #2: ata_piix-pata-apple.patch --]
[-- Type: text/plain, Size: 596 bytes --]

diff --git a/drivers/ata/ata_piix.c b/drivers/ata/ata_piix.c
index 81b7ae3..93b5741 100644
--- a/drivers/ata/ata_piix.c
+++ b/drivers/ata/ata_piix.c
@@ -214,6 +214,8 @@ static const struct pci_device_id piix_pci_tbl[] = {
 	/* ICH7/7-R (i945, i975) UDMA 100*/
 	{ 0x8086, 0x27DF, PCI_ANY_ID, PCI_ANY_ID, 0, 0, ich_pata_100 },
 	{ 0x8086, 0x269E, PCI_ANY_ID, PCI_ANY_ID, 0, 0, ich_pata_100 },
+	/* ICH8 Mobile PATA Controller, Apple */
+	{ 0x8086, 0x2850, 0x106b, 0x00a1, 0, 0, ich_pata_66 },
 	/* ICH8 Mobile PATA Controller */
 	{ 0x8086, 0x2850, PCI_ANY_ID, PCI_ANY_ID, 0, 0, ich_pata_100 },