Re: [ECOS] Is Redboot run in supervisor mode?

[Jonathan Larmour <jifl at eCosCentric dot com>]

jameshq@liverpool.ac.uk wrote:
> Thank you very much Jonathan. 
> Could I ask 4 more questions about the ecos for arm. Thanks a lot in
> advance.
>
> I am on ARM target 
> Q1. When initializing a user thread (cyg_thread_create()), its mode
> will be default to CPSR_SUPERVISOR_MODE.(HAL_THREAD_INIT_CONTEXT) then
> the user thread will be loaded into supervisor mode rather than user
> mode, is this correct? 
> Q2. if so why not use user mode to run the user created thread? 
> Q3. Is there any particular reason not using user mode for this? 
> Q4. So seems everything in ecos for ARM target are run in supervisor
> mode correct(except exception)? no user mode at all.
Yes, as I said it's supervisor mode for everything. There is no 
distinction between kernel and user programs in eCos as it's all fully 
linked. User mode would just get in the way.

Jifl

> -----Original Message-----
> From: Jonathan Larmour [mailto:jifl@eCosCentric.com]
[snip]
> I believe Qiang is on ARM in which case it's supervisor (SVC) mode for
>
> everything. Even on interrupts we switch to SVC mode as soon as we
> can.

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