On Fri, Mar 19, 2021 at 05:07:53PM +0000, Russell King - ARM Linux admin wrote:
On Thu, Mar 18, 2021 at 05:56:58AM +0100, Christoph Hellwig wrote:
footbridge_defconfig enables CONFIG_IDE but no actual host controller
driver, so just drop it.
I have been using the Cypress 82C693 IDE driver on Footbridge for a
CD ROM drive, and I know it doesn't work with the PATA driver - as
I need to disable BM DMA, otherwise the 82C693/DC21285 combination
deadlocks the PCI bus. The PATA driver doesn't support disabling
BM DMA without disabling it for all PATA ports, which is really
annoying for my IT821x card in the same machine.
So, I'm rather stuck using the PATA driver for the HDDs and the
IDE driver for the CD ROM.
That said, a commit a while back "cleaning up" the PCI layer appears
to have totally shafted the 82C693, as the kernel tries to request
IO resources at the legacy IDE addresses against the PCI bus resource
which only covers 0x1000-0xffff. Hence, the 82C693 IDE ports are non-
functional at the moment.
I'm debating about trying to find a fix to the PCI breakage that was
introduced by "ARM: move PCI i/o resource setup into common code".
I hadn't noticed it because I don't use the CD ROM drive very often,
and I don't upgrade the kernel that often either on the machine -
but it has been running 24x7 for almost two decades.
Okay, a bit more on this...
If I extend the arch/arm/kernel/bios32.c code to kill BARs 2/3 (which
actually are not present on the CY82C693) then the IDE driver works
for me, but the PATA driver does not:
cy82c693 0000:00:06.1: IDE controller (0x1080:0xc693 rev 0x00)
cy82c693 0000:00:06.1: not 100% native mode: will probe irqs later
legacy IDE will be removed in 2021, please switch to libata
Report any missing HW support to linux-ide@xxxxxxxxxxxxxxx
ide0: BM-DMA at 0x1080-0x1087
ide1: BM-DMA at 0x1088-0x108f
Probing IDE interface ide0...
hda: PIONEER DVD-RW DVR-105, ATAPI CD/DVD-ROM drive
hda: host max PIO4 wanted PIO255(auto-tune) selected PIO4
...
(unbind Cypress_IDE and try binding pata_cypress)
pata_cypress 0000:00:06.1: no available native port
--
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