Réf. : Re: Réf. : RE: mmap : please help !
From: <hidden>
Date: 2005-04-14 14:37:15
Hello Jean-Christophe,
That's right, I verify all the useful parameters in my driver and
everything seems OK.
But, the real question is : if you use the /dev/mem (with open() and mm=
ap
()), could you use, in the user space, the pointer returned by the mmap=
function to access the physical memory or do you have to use read/write=
(on
the file descriptor) to access physical memory because i haven't the sa=
me
results according to the used method.
Thanks for 'od' but i haven't in my packages.
Sophie.
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Jean-Christop =
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he Dubois Pour : scarayol@assystembrime=
.com =
<jdubois@mc.c cc : linuxppc-embedded@ozla=
bs.org =
om> Objet : Re: R=E9f. : RE: =
mmap : please help ! =
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14/04/05 =
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12:09 =
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Hello Sophie,
On Thu, 2005-04-14 at 11:38 +0200, scarayol@assystembrime.com wrote:St=E9phane, thanks for your help. But I think that, except instruction eieio, I do similar things. You=
use
the virtual address returned by mmap but have you the same values if =
you
use write/read(axs_mem_fd,...) instead of in_8/out_8. That is my problem : I want to be sure that when I use the virtual
address
returned by mmap, I access really to the physical memory mapped area.=
As the /dev/map_mc is your custom driver it should be fairly easy for you to check the parameters you pass to remap_page_range().
Do you know a shell command in order to dump the memory and verify wh=
at I
do ?
try "od" JC
---------------------------------------------------------- Sophie CARAYOL TECHNOLOGIES & SYSTEMES 50 rue du Pr=E9sident Sadate F - 29337 QUIMPER CEDEX T=E9l: +33 2 98 10 30 06 mailto:scarayol@assystembrime.com ---------------------------------------------------------- _______________________________________________ Linuxppc-embedded mailing list Linuxppc-embedded@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-embedded
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