[freertos - Open Discussion and Support] Freertos for NXP 23xx - nesting interrupts
SourceForge.net
Read and respond to this message at:
https://sourceforge.net/projects/freertos/forums/forum/382005/topic/4831083
By: piero74
Hi
I'm working on NXP2365, using freertos V5.3.0
The porting i have, doesn't allow to use nesting ISRs.
But i need them. My problem is the following:
i have 2 ISRs, and both call sendToQueueFromISR, so both have the ASM wrapper
necessary for RTOS.
I need that one can be interrupted by the other (nesting), but i don't know
how.
is there a solution already done for my porting?
thank in advance
Piero
_____________________________________________________________________________________
You are receiving this email because you elected to monitor this topic or entire forum.
To stop monitoring this topic visit:
https://sourceforge.net/projects/freertos/forums/forum/382005/topic/4831083/unmonitor
To stop monitoring this forum visit:
https://sourceforge.net/projects/freertos/forums/forum/382005/unmonitor
SourceForge.net
Read and respond to this message at:
https://sourceforge.net/projects/freertos/forums/forum/382005/topic/4831083
By: piero74
I found this item on forum
https://sourceforge.net/projects/freertos/forums/forum/382005/topic/4800305
but i didn't understand how i can use these macros in my arm7 porting
bye
SourceForge.net
Read and respond to this message at:
https://sourceforge.net/projects/freertos/forums/forum/382005/topic/4831083
By: piero74
When an ISR with RTOS wrapper is called for an IRQ, all registers are stored
in current task stack.
Also, ARM7 switch to IRQ stack (ARM7 has its own stack for IRQ). This is the
standerad wrapper:
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; wrapper isr functionfor FREERTOS macro definition
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
wrapISR MACRO function
portSAVE_CONTEXT ; Save the context of the current task.
bl function ; Call the ISR routine.
portRESTORE_CONTEXT ; Restore the context of the current task -
; which may be different to the task that
; was interrupted.
ENDM
Follow Brent idea, to have ISR that can be nested, i should need only this special
wrapper:
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; wrapper isr functionfor FREERTOS macro definition
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
wrapISR MACRO function
portSAVE_CONTEXT ; Save the context of the current task.
ISR_ENABLE_NEST() ;enable other IRQ to nest
bl function ; Call the ISR routine.
ISR_DISABLE_NEST() ; disable nesting
portRESTORE_CONTEXT ; Restore the context of the current task -
; which may be different to the task that
; was interrupted.
ENDM
Any comment about this solution? i wants to review it with people on forum before
try it.
thanks for feedbacks
SourceForge.net
Read and respond to this message at:
https://sourceforge.net/projects/freertos/forums/forum/382005/topic/4831083
By: piero74
Hi
First, after some research, i think the solution proposed above from me
is wrong.
Second, Richard Barry said that there is no ARM7 RTOS that use nested
interrupt.
Instead i found that uCOS, has this feature: i have a document that explain
this, and searching inside the uCOS code, i found comments in kernel functions
that shows that nested interrupt are used.
Richard, do you have never have a look to that code? Is it really far from FREERTOS
kernel or o a similar idea can be included?
I work with FREERTOS with 2 different ports, ARM7 and PIC32, and it is very
strange that with one (PIC32) i can nest IRQ (and i did it, very useful for
our very complex application) and with the other one (ARM7) i cannot: i'd like
to to work in the same way for both ports.
Richard, Can i aspect something in the near future about nested irq for ARM7?
Thanks in advance
SourceForge.net
Read and respond to this message at:
https://sourceforge.net/projects/freertos/forums/forum/382005/topic/4831083
By: piero74
document about ucos here:
http://electronix.ru/forum/index.php?act=attach&type=post&id=31636
SourceForge.net
Read and respond to this message at:
https://sourceforge.net/projects/freertos/forums/forum/382005/topic/4831083
[quote]Richard Barry said that there is no ARM7 RTOS that use nested
interrupt[/quote]
If you are going to make statements like that, please provide a reference.
I do not recall ever having said such a thing, and, if I did somewhere, would
not agree with it now. I do recall saying that even ARM's own RTOS does not
support it, but then I am only going on what I have been told, and I have not
used it myself.
[quote]Richard, Can i aspect something in the near future about nested irq for
ARM7?[/quote]
With my current massive work load, and the move to ARM Cortex-M devices, it
is unlikely there would be any major developments on ARM7 devices. There may
however be a time when an ARM9 port is developed further, and the changes to
that are easy to pass into the ARM7 world too. If you have a port that supports
interrupt nesting, then I would definitely be interested and encourage you to
post it to the FreeRTOS Interactive site.
Regards
SourceForge.net
Read and respond to this message at:
https://sourceforge.net/projects/freertos/forums/forum/382005/topic/4831083
By: richardbarry
For the record, I have just deleted your post that linked to a document that
describes the internal workings of a competitive product. For legal reasons,
I cannot take responsibility for publishing my own kernel implementation while
simultaneously hosting links to competitors implementations.
If you wish to draw other peoples attention to the document, please host the
link yourself, then here you can post a link to your own page.
Thank you for your understanding. I do not take deleting posts lightly.
Regards.
SourceForge.net
Read and respond to this message at:
https://sourceforge.net/projects/freertos/forums/forum/382005/topic/4831083
[quote] I do recall saying that even ARM's own RTOS does not support it, but
then I am only going on what I have been told, and I have not used
it myself.[/quote]
CORRECT! i found your post and i read it: MY MISTAKE, sorry!!
[quote] If you have a port that supports interrupt nesting, then I would definitely
be interested and encourage you to post it to the FreeRTOS Interactive
site[/quote]
I tried something but i failed.
I have only a workaround, i modified a little the kernel to allow to my self
to use SWI (reserved for RTSO tick) also for call functions inside SWI ISR,
just using a macro that set a global variable (it is an index that allow to
choose function) and call asm(SWI).
With this workaround, i'm using FIQ (even managing multiple sources in ISR)
to nest IRQs, and i use the help of my custom SWI to allow that something in
FIQ send a message to task (custom routine just use sendqueueInISR according
with global variable)
SWI has low priority than IRQ, so message will be sent AFTER the end of current
IRQ, so FIQ ISR could be a very fast routine with a very low latency, will have
the ability to send (even postponed) a message to tasks, and IRQ routines nested
will not delayed for a long time (send message from ISR waste time that could
be too big for some IRQ with strict time constrains )
Let me know if could be useful to post this idea (i'm very busy at work too,
so it will not be sooner)
Also, i have a contribution to implement above RTOS shared buffers, where many
consumer tasks can use big data (buffers) from a producer task, forward pieces
to other tasks, exchanging small info using queues, and without lock producer
during buffer elaboration (i didn't use semaphores)
Again, Let me know if could be useful to post this idea (i'm very busy at work
too, so it will not be sooner: also i should document it very well)
Bye
Piero
SourceForge.net
Read and respond to this message at:
https://sourceforge.net/projects/freertos/forums/forum/382005/topic/4831083
By: piero74
[quote]Thank you for your understanding. I do not take deleting posts
lightly.[/quote]
I understood. Sorry