[Bug 228302] Re: [HARDY-LUCID] No DMA nor 32bits IO support

[Conn O Griofa]

Igor,

Let's try to get a summary of action needed.

Problem: the "pata_ali" kernel driver does not support ATAPI DMA
transfers properly on certain ALI chipsets (even if force-enabled via
the driver option "atapi_dma=1"). The "ata_generic" kernel driver
supports ATAPI DMA transfers for such chipsets and has a special kernel
boot option, "all_generic_ide", which causes it to override the
manufacturer-specific drivers. However, this option does not work
correctly when the "ata_generic" and "pata_ali" drivers are compiled-in
to the kernel, which means that the "ata_generic" driver is impossible
to use.

Solution:

Change these kernel config parameters:
CONFIG_PATA_ALI=y
CONFIG_ATA_GENERIC=y

To the following:
CONFIG_PATA_ALI=m
CONFIG_ATA_GENERIC=m

Result:
1. For all other users: there will be no functional difference between the original and modified kernel configuration (as long as the logic to automatically modprobe the "ata_generic"/"pata_ali" kernel modules is properly in place)
2. For users with buggy ALI chipsets, they can now take advantage of the kernel boot options "all_generic_ide" and/or to manually blacklist the "pata_ali" driver, which will cause the ata_generic driver to be used (and as a result, ATAPI DMA will work properly).

Am I missing anything, Igor?

-- 
[HARDY-LUCID] No DMA nor 32bits IO support
https://bugs.launchpad.net/bugs/228302
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