Hi,
I was wondering if there's any real time clock implementation for I.MX6 in sel4.
And if there isnt any, what would be the best way to use a timer in sel4 (since I saw many implementations of those)? through sel4platsupport_get_default_timer?
Best, Oak
Hi Oak,
What sort of timer are you looking for? We do not currently have any drivers on or in seL4 for the I.MX6 that output real time, if by real time you mean wall clock time.
The real-time branch, which is tickless, has an in kernel driver for the 64 bit global timer [1] which counts time since boot and uses this to schedule periodic threads.
Thanks, let me know if I can be further help. Anna.
[1] https://github.com/seL4/seL4/blob/rt/src/arch/arm/machine/global_timer.c#L98
On 29/06/2016 10:17 am, Norrathep Rattanavipanon wrote: Hi,
I was wondering if there's any real time clock implementation for I.MX6 in sel4.
And if there isnt any, what would be the best way to use a timer in sel4 (since I saw many implementations of those)? through sel4platsupport_get_default_timer?
Best, Oak
-- Norrathep (Oak) Rattanavipanon M.S. in Computer Science University of California - Irvine
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Thanks Anna.
We are looking for a way to get timestamp (wall clock) that can be used in the userland for authenticating an incoming message from remote server.
I see that the real-time clock driver is not implemented yet but an accurate timer would do the job too.
So any recommendation on which timer implementation to use? Would this one work? https://github.com/seL4/libsel4platsupport/blob/master/src/mach/imx/timer.c
Thanks, Oak
On Tue, Jun 28, 2016 at 5:17 PM, Norrathep Rattanavipanon nrattana@uci.edu wrote:
Hi,
I was wondering if there's any real time clock implementation for I.MX6 in sel4.
And if there isnt any, what would be the best way to use a timer in sel4 (since I saw many implementations of those)? through sel4platsupport_get_default_timer?
Best, Oak
-- Norrathep (Oak) Rattanavipanon M.S. in Computer Science University of California - Irvine
Hi Oak,
For an accurate timer at user level you can use the gpt driver here : https://github.com/seL4/seL4_libs/blob/master/libsel4platsupport/src/mach/im...
Note that a while ago we combined a lot of our library repos, so libsel4platsupport is not part of the larger seL4_libs. The stand alone version is no longer updated.
Cheers, Anna.
On 29/06/2016 1:39 pm, Norrathep Rattanavipanon wrote: Thanks Anna.
We are looking for a way to get timestamp (wall clock) that can be used in the userland for authenticating an incoming message from remote server.
I see that the real-time clock driver is not implemented yet but an accurate timer would do the job too.
So any recommendation on which timer implementation to use? Would this one work? https://github.com/seL4/libsel4platsupport/blob/master/src/mach/imx/timer.c
Thanks, Oak
On Tue, Jun 28, 2016 at 5:17 PM, Norrathep Rattanavipanon <mailto:nrattana@uci.edunrattana@uci.edumailto:nrattana@uci.edu> wrote: Hi,
I was wondering if there's any real time clock implementation for I.MX6 in sel4.
And if there isnt any, what would be the best way to use a timer in sel4 (since I saw many implementations of those)? through sel4platsupport_get_default_timer?
Best, Oak
-- Norrathep (Oak) Rattanavipanon M.S. in Computer Science University of California - Irvine
-- Norrathep (Oak) Rattanavipanon M.S. in Computer Science University of California - Irvine
_______________________________________________ Devel mailing list Devel@sel4.systemsmailto:Devel@sel4.systems https://sel4.systems/lists/listinfo/devel
--
Anna Lyons Kernel engineer / PhD Student DATA61 | CSIRO E anna.lyons@nicta.com.aumailto:anna.lyons@nicta.com.au www.data61.csiro.auhttp://www.data61.csiro.au
CSIRO's Digital Productivity business unit and NICTA have joined forces to create digital powerhouse Data61
________________________________
The information in this e-mail may be confidential and subject to legal professional privilege and/or copyright. National ICT Australia Limited accepts no liability for any damage caused by this email or its attachments.
I see. Thanks for the info.
So by default, the root task has complete control over physical address containing gpt data. And if I want to use the gpt inside a different task, the root task has to pass its capability to that task. Without that, any non-root task wouldnt be able to access it.
Am I understanding the timer's capability access control correctly?
Oak
On Tue, Jun 28, 2016 at 8:39 PM, Norrathep Rattanavipanon nrattana@uci.edu wrote:
Thanks Anna.
We are looking for a way to get timestamp (wall clock) that can be used in the userland for authenticating an incoming message from remote server.
I see that the real-time clock driver is not implemented yet but an accurate timer would do the job too.
So any recommendation on which timer implementation to use? Would this one work? https://github.com/seL4/libsel4platsupport/blob/master/src/mach/imx/timer.c
Thanks, Oak
On Tue, Jun 28, 2016 at 5:17 PM, Norrathep Rattanavipanon < nrattana@uci.edu> wrote:
Hi,
I was wondering if there's any real time clock implementation for I.MX6 in sel4.
And if there isnt any, what would be the best way to use a timer in sel4 (since I saw many implementations of those)? through sel4platsupport_get_default_timer?
Best, Oak
-- Norrathep (Oak) Rattanavipanon M.S. in Computer Science University of California - Irvine
-- Norrathep (Oak) Rattanavipanon M.S. in Computer Science University of California - Irvine
Yes, exactly.
If you need to handle timer interrupts as well, the irq handler capalility for that irq number will need to be passed to the other task.
Cheers, Anna.
On 30/06/2016 9:08 am, Norrathep Rattanavipanon wrote: I see. Thanks for the info.
So by default, the root task has complete control over physical address containing gpt data. And if I want to use the gpt inside a different task, the root task has to pass its capability to that task. Without that, any non-root task wouldnt be able to access it.
Am I understanding the timer's capability access control correctly?
Oak
On Tue, Jun 28, 2016 at 8:39 PM, Norrathep Rattanavipanon <mailto:nrattana@uci.edunrattana@uci.edumailto:nrattana@uci.edu> wrote: Thanks Anna.
We are looking for a way to get timestamp (wall clock) that can be used in the userland for authenticating an incoming message from remote server.
I see that the real-time clock driver is not implemented yet but an accurate timer would do the job too.
So any recommendation on which timer implementation to use? Would this one work? https://github.com/seL4/libsel4platsupport/blob/master/src/mach/imx/timer.c
Thanks, Oak
On Tue, Jun 28, 2016 at 5:17 PM, Norrathep Rattanavipanon <mailto:nrattana@uci.edunrattana@uci.edumailto:nrattana@uci.edu> wrote: Hi,
I was wondering if there's any real time clock implementation for I.MX6 in sel4.
And if there isnt any, what would be the best way to use a timer in sel4 (since I saw many implementations of those)? through sel4platsupport_get_default_timer?
Best, Oak
-- Norrathep (Oak) Rattanavipanon M.S. in Computer Science University of California - Irvine
-- Norrathep (Oak) Rattanavipanon M.S. in Computer Science University of California - Irvine
-- Norrathep (Oak) Rattanavipanon M.S. in Computer Science University of California - Irvine
_______________________________________________ Devel mailing list Devel@sel4.systemsmailto:Devel@sel4.systems https://sel4.systems/lists/listinfo/devel
--
Anna Lyons Kernel engineer / PhD Student DATA61 | CSIRO E anna.lyons@nicta.com.aumailto:anna.lyons@nicta.com.au www.data61.csiro.auhttp://www.data61.csiro.au
CSIRO's Digital Productivity business unit and NICTA have joined forces to create digital powerhouse Data61
________________________________
The information in this e-mail may be confidential and subject to legal professional privilege and/or copyright. National ICT Australia Limited accepts no liability for any damage caused by this email or its attachments.
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Anna Lyons -
Norrathep Rattanavipanon