libata:pata_atiixp: Don't use unconnected secondary port on SB600

The AMD SB600 southbridge has an PATA IDE interface, but the
    secondary port has no physical connections, so is disabled in
    the PCI header which makes it appear as a legacy port.

    On most systems this causes no trouble, but the Amigaone X1000 has
    an SB600 connected to a PowerPC SoC PCI-e root port, with an
    emulated ISA bus. On this system a kernel panic occurs at boot
    time during device attach for the secondary port.

    Mark the port as 'dummy' to prevent this. As a bonus, disabling
    this will slightly speed up booting on PC systems using an
    SB600 as they will now skip 2 known empty ports.

    Signed-off-by: Darren Stevens <Darren@stevens-zone.net>

Signed-off-by: Tejun Heo <tj@kernel.org>
This commit is contained in:
Darren Stevens 2017-12-31 21:11:05 +00:00 committed by Tejun Heo
parent 36fffd6a1f
commit e47ecd4e48
1 changed files with 4 additions and 0 deletions

View File

@ -278,6 +278,10 @@ static int atiixp_init_one(struct pci_dev *pdev, const struct pci_device_id *id)
};
const struct ata_port_info *ppi[] = { &info, &info };
/* SB600 doesn't have secondary port wired */
if((pdev->device == PCI_DEVICE_ID_ATI_IXP600_IDE))
ppi[1] = &ata_dummy_port_info;
return ata_pci_bmdma_init_one(pdev, ppi, &atiixp_sht, NULL,
ATA_HOST_PARALLEL_SCAN);
}