This is the mail archive of the ecos-discuss@sources.redhat.com mailing list for the eCos project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: help needed


The subject says it all, doesn't it?  I'd suggest that rather than
asking all of these questions, all of which are discussed in the
appropriate documentation, that you consider getting some real
help using and understanding eCos.  Professional support is 
available from a number of sources.

On Tue, 2002-09-17 at 06:33, Vinayak P Risbud wrote:
>         Hi I am using gnu assembler to compile this code.
> 
>         Can any one explain me, what is the meaning of last 3 statements
> ?

This particular sequence is used to enable the MMU and instruction cache
on the ARM platform.  The details of the format can be found in the
ARM manuals (for the instructions themselves) and the GCC documentation
(using inline assembly).

> 
>     asm volatile (
> \
> 
>         "mrc  p15,0,r1,c1,c0,0;"
> \
>         "orr  r1,r1,#0x1000;"
> \
>         "orr  r1,r1,#0x0003;" /* enable ICache (also ensures   */
> \
>                               /* that MMU and alignment faults */
> \
>                               /* are enabled)                  */
> \
>         "mcr  p15,0,r1,c1,c0,0"
> \
>         :
> \
>         :
> \
>         : "r1" /* Clobber list */
> \
>         );


-- 
------------------------------------------------------------
Gary Thomas                  |
eCosCentric, Ltd.            |  
+1 (970) 229-1963            |  eCos & RedBoot experts
gthomas@ecoscentric.com      |
http://www.ecoscentric.com/  |
------------------------------------------------------------


-- 
Before posting, please read the FAQ: http://sources.redhat.com/fom/ecos
and search the list archive: http://sources.redhat.com/ml/ecos-discuss


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]