Previously, if two ID allocators for different kernel objects had the
same size, the kernel-object framework managed both objects types
through the same allocator instance. This is caused by the use of
unsynchronized singletons in the accessor functions and can be avoided
by creating new types through inheritance instead of using typedefs.
Anyways, this fix is a little bit ugly and should replaced by avoiding
the use of unsynchronized singletons in the future.
fix#906
This patch eliminates calls of 'cmpxchg' prior enabling the MMU. This is
needed because the 'ldrex' and 'strex' instructions do not always work
with MMU and L1 cache disabled, i.e., on Raspberry Pi.
Merge core only libs into the target make-files.
Use base-hw specific Board drivers that inherit
from generic Board_base.
Use Page_flags::access_t instead of additional
page_flags_t.
Fix#570
Instead of allocating and freeing the space that is needed for the
kernel thread objects from core, wich is not convenient with the
quota system, platform thread now holds the space as array by
itself.
Unfortunately we cannot measure the space size by a static function
anymore, so kernel thread had to be moved from kernel.cc into its
own header. This way platform thread can use sizeof().
Fix#543
By now there is no use case for read/write a single register
of a thread state. Thus the new syscalls 'read_thread_state' and
'write_thread_state' replace the old ones 'read_register' and
'write_register'.
Add 'resume_faulter' syscall that is similar to 'resume_thread', but
is called only when resuming a thread after resolving its pagefault.
This way the kernel can flush caches after resolving a pagefault. This is
because by now the MMU doesn't use caches when doing a pagetable walk.
'Page_flags' maps application-specific memory attributes
to the TLB-specific memory attributes. Thereby it avoids
functions with lots of parameters, by declaring appropriate
bitfields on a single POD value.
'Core_tlb' ensures that core never throws pagefaults,
in contrast to its base 'Tlb' that is planned to use displacement
in the future.
'Core_tlb' enables the application of differenet memory attributes
in core, according to the board specific partitioning of the physical
address space. This way it enables caching in core.
Enable caches. Core is not cached by now. This is because kernel
creates core space and doesn't know any memory attributes by now.
Cacheable pages are cached write-through without write-allocate.
Caching and write-combining is not supported for IOMEM by now.