Re: PIC IO Memory Access Question

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Hi Daniel :)

On Sat, Dec 18, 2010 at 04:31, Daniel (Youngwhan) Song
<breadncup@xxxxxxxxx> wrote:
> Hi, there,
>
> I am currently using regular X86 32 bit architecture having PCI and PCIe
> interface in a certain embedded system.
>
> One of PCIe device is attached, and I am trying to load the kernel module.
>
> One problem I have is that a certain area in the iomapped shows only 0xFFFF
> values. So, initially, I thought the hardware device module itself has a
> problem, but when I insert it in PC rather than my embedded system, it shows
> valid values.

Two things that aren't obvious from your code snippet:
a. Are the base addresses the same for both code ? Or are you using
different one? Have you check the manual to decide in which address
(range) you should map?

b. How do you know which one is valid and which one is not?

To me: both looks "good", depending on whether the mapping address is
considered valid or not.

-- 
regards,

Mulyadi Santosa
Freelance Linux trainer and consultant

blog: the-hydra.blogspot.com
training: mulyaditraining.blogspot.com

--
To unsubscribe from this list: send an email with
"unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx
Please read the FAQ at http://kernelnewbies.org/FAQ



[Index of Archives]     [Newbies FAQ]     [Linux Kernel Mentors]     [Linux Kernel Development]     [IETF Annouce]     [Git]     [Networking]     [Security]     [Bugtraq]     [Yosemite]     [MIPS Linux]     [ARM Linux]     [Linux RAID]     [Linux SCSI]     [Linux ACPI]
  Powered by Linux