Fsys.eide / DMA

QNX Newsgroups (Archives) qdn.public.qnx4
1

Hi,

Do you know if Fsys.eide is still using non-DMA mode by default ?

Can you remember me the hiddent option to enable DMA ?

Is it safe on new bios computers ?

Regards.

2

“jhr” <nospam@nospam.com> wrote in message news:9fpual$98m$1@inn.qnx.com…

Hi,

Do you know if Fsys.eide is still using non-DMA mode by default ?

Can you remember me the hiddent option to enable DMA ?

Is it safe on new bios computers ?

To my knowledge QNX4 driver does not use DMA.

Regards.

3

Hi,

By default concurrent DMA I/O is disabled…to enable DMA use the ‘-d’ switch as described in the help docs.

Regards,

Joe

jhr <nospam@nospam.com> wrote:

Hi,

Do you know if Fsys.eide is still using non-DMA mode by default ?

Can you remember me the hiddent option to enable DMA ?

Is it safe on new bios computers ?

Regards.

4

“Hardware Support Account” <hw@qnx.com> wrote in message
news:9fqk3o$fgt$1@nntp.qnx.com…

Hi,

By default concurrent DMA I/O is disabled…to enable DMA use the ‘-d’
switch as described in the help docs.

I’m not 100% sure about this; I think option is somewhat generic to all
Fsys driver.
The doc says it allow concurrent DMA if DMA is used by the driver. In the
case of Fsys.eide, unless it was changed recently, it does not support DMA
at all.

Regards,

Joe

jhr <> nospam@nospam.com> > wrote:
Hi,

Do you know if Fsys.eide is still using non-DMA mode by default ?

Can you remember me the hiddent option to enable DMA ?

Is it safe on new bios computers ?

Regards.

5

Hardware Support Account <hw@qnx.com> wrote:
: Hi,
: By default concurrent DMA I/O is disabled…to enable DMA use the
: ‘-d’ switch as described in the help docs.
: Regards,
: Joe

Sorry, that is not what this option means. It controls whether Fsys
will allow concurrent DMA to devices which support it (as some DMA
controllers etc cannot handle this and the IO calldowns must be
single-threaded). It does not control DMA in the device driver itself.
Qnx4 Fsys.eide has no official support for DMA …

6

John Garvey wrote:
[snip]

Qnx4 Fsys.eide has no official support for DMA …
^^^^^^^^

Odd phrasing, John. Something you’re not telling us?