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@ -113,18 +113,15 @@ To provide end users with simple API, Unicorn does lots of dirty hacks within qe
Yes, it’s possible but that is not Unicorn’s goal and there is no simple switch in qemu to disable softmmu. Yes, it’s possible but that is not Unicorn’s goal and there is no simple switch in qemu to disable softmmu.
## How can I interact with MMU/TLB? Starting from 2.0.2, Unicorn will emulate the MMU depending on the emulated architecture without further hacks. That said, Unicorn offers the full ability of the target MMU implementation. While this enables more possibilities of Uncorn, it has a few drawbacks:
By default Unicorn will emulate the MMU depending on the emulated architecture. - As previous question points out already, some memory regions are not writable/executable.
So you can use the features and interfaces of this MMU. - You have to always check architecture-specific registers to confirm MMU status.
You or the emulated code can write to the memory and corresponding register to use the MMU. - `uc_mem_map` will always deal with physical addresses while `uc_emu_start` accepts virtual addresses.
There is also use the `UC_TLB_VIRTUAL` mode. Therefore, if you still prefer the previous `paddr = vaddr` simple mapping, we have a simple experimental MMU implementation that can be switched on by: `uc_ctl_tlb_mode(uc, UC_TLB_VIRTUAL)`. With this mode, you could also add a `UC_HOOK_TLB_FILL` hook to manage the TLB. When a virtual address is not cached, the hook will be called. Besides, users are allowed to flush the tlb with `uc_ctl_flush_tlb`.
This mode defaults to a simple paddr := vaddr mapping.
You can also add an `UC_HOOK_TLB_FILL` hook to manage the TLB. In theory, `UC_TLB_VIRTUAL` will achieve better performance as it skips all MMU details, though not benchmarked.
The hook is called, when a virtuall address is not cached and Unicorn is in `UC_TLB_VIRTUAL` mode.
You can manual flush the cache with `uc_ctl_flush_tlb`.
## I'd like to make contributions, where do I start? ## I'd like to make contributions, where do I start?