Currently, the following instructions are translated:
- CACHE (indexed)
- CACHE (va based): translated to a SYNCI, overkill on D-CACHE operations,
but still much faster than a trap.
- mfc0/mtc0: the virtual COP0 registers for the guest are implemented as
2-D array.
[COP#][SEL] and this is mapped into the guest kernel address space @ VA 0x0.
mfc0/mtc0 operations are transformed to load/stores.
Signed-off-by: Sanjay Lal <sanjayl@kymasys.com>
Cc: kvm@vger.kernel.org
Cc: linux-mips@linux-mips.org
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
- Note that this file is statically linked with the rest of the host kernel (KSEG0). This is because kernel modules are
loaded into mapped space on MIPS and we want to make sure that we don't get any host kernel TLB faults while
manipulating TLBs.
- Virtual Guest TLBs are implemented as 64 entry array regardless of the number of host TLB entries.
- Shadow TLBs map Guest virtual addresses to Host physical addresses.
- TLB miss handling details:
Guest KSEG0 TLBMISS (0x40000000 – 0x60000000): Transparent to the Guest.
Guest KSEG2/3 (0x60000000 – 0x80000000) & Guest UM TLBMISS (0x00000000 – 0x40000000)
Lookup in Guest/Virtual TLB
If an entry doesn’t match
deliver appropriate TLBMISS LD/ST exception to the guest
If entry does exist in the Guest TLB and is NOT Valid
Deliver TLB invalid exception to the guest
If entry does exist in the Guest TLB and is VALID
Inject the TLB entry into the Shadow TLB
Signed-off-by: Sanjay Lal <sanjayl@kymasys.com>
Cc: kvm@vger.kernel.org
Cc: linux-mips@linux-mips.org
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
- The Guest kernel is run in UM and privileged instructions cause a trap.
- If the instruction causing the trap is in a branch delay slot, the branch
needs to be emulated to figure out the PC @ which the guest will resume
execution.
Signed-off-by: Sanjay Lal <sanjayl@kymasys.com>
Cc: kvm@vger.kernel.org
Cc: linux-mips@linux-mips.org
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
- Implements the arch specific APIs for KVM, some are stubs for MIPS
- kvm_mips_handle_exit(): Main 'C' distpatch routine for handling exceptions while in "Guest" mode.
- Also implements in-kernel timer interrupt support for the guest.
Signed-off-by: Sanjay Lal <sanjayl@kymasys.com>
Cc: kvm@vger.kernel.org
Cc: linux-mips@linux-mips.org
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
- __kvm_mips_vcpu_run: main entry point to enter guest, we save kernel context, load
up guest context from and ERET to guest context.
- mips32_exception: L1 exception handler(s), save k0/k1 and jump to main handlers.
- mips32_GuestException: Generic exception handlers for exceptions/interrupts while in
guest context. Save guest context, restore some kernel context and jump to
main 'C' handler: kvm_mips_handle_exit()
Signed-off-by: Sanjay Lal <sanjayl@kymasys.com>
Cc: kvm@vger.kernel.org
Cc: linux-mips@linux-mips.org
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
- Add the KVM option to MIPS build files.
- Add default config files for KVM host/guest kernels.
- Change the link address for the Malta KVM Guest kernel to UM (0x40100000).
- Add KVM Kconfig file with KVM/MIPS specific options
Signed-off-by: Sanjay Lal <sanjayl@kymasys.com>
Cc: kvm@vger.kernel.org
Cc: linux-mips@linux-mips.org
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
In the Linux kernel traditionally pfns are represented by an unsigned long.
However a few bits of the SGI IP27 platform code that were ported from
IRIX are using pfn_t for historic reasons. This is conflicting with
KVM's use of pfn_t.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Ralf Baechle
Sanjay Lal
Jonas Gorski
John Crispin