I can never remember whether the static page table list contains the
table's physical or kernel virtual address.. Add the fact as a comment
there.
Also add the limitations that come from this static page table approach
for Sv32.
The function is not relevant any longer, remove it. Also remove
save_addrenv_t, the parameter taken by up_addrenv_restore.
Implement addrenv_select() / addrenv_restore() to handle the temporary
instantiation of address environments, e.g. when a process is being
created.
This is preparation for moving address environments out of the group
structure into the tcb.
Why move ? Because the group is destroyed very early in the exit phase,
but the MMU mappings are needed until the context switch to the next
process is complete. Otherwise the MMU will lose its mappings and the
system will crash.
1.Move __XSTR from include/arch.h to include/irq.h
2.Move FLOAD/FSTORE and REGLOAD/REGSTORE from include/arch.h to src/common/riscv_internal.h
Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
This implements initial support for kernel build (address environments,
page allocator) for RISC-V.
This is done a bit differently compared to the ARMV7 implementation:
- Support implemented for Sv39 MMU, however the implementation should be
extensible for other MMU types also.
- Instead of preserving and moving the L1 references around, a canonical
approach is used instead, where the page table base address register
is switched upon context switch.
- To preserve a bit of memory, only a single L1/L2 table is supported,
this gives access to 1GiB of virtual memory for each process, which
should be more than enough.
Some things worth noting:
- Assumes page pool is mapped with vaddr=paddr mappings
- The CONFIG_ARCH_XXXX_VBASE and CONFIG_ARCH_XXXX_NPAGES values are
ignored, with the exception of CONFIG_ARCH_DATA_VBASE which is used
for ARCH_DATA_RESERVE
- ARCH_DATA_RESERVE is placed at the beginning of the userspace task's
address environment
They are not really defined and used in any where:
uint32_t up_getmisa(void);
uint32_t up_getarchid(void);
uint32_t up_getimpid(void);
uint32_t up_getvendorid(void);
uint32_t up_gethartid(void);
Signed-off-by: Huang Qi <huangqi3@xiaomi.com>
Ken Pettit has submitted the ICLA and we can migrate the licenses
to Apache.
Sebastien Lorquet has submitted the ICLA and we can migrate the licenses
to Apache.
Gregory Nutt has submitted the SGA and we can migrate the licenses
to Apache.
Signed-off-by: Alin Jerpelea <alin.jerpelea@sony.com>
