Implement the optional segmentation control feature in the virtual to
physical address translation code.
The fixed legacy segment and xkphys handling is replaced with a dynamic
layout based on the segmentation control registers (which should be set
up even when the feature is not exposed to the guest).
Backports commit 480e79aedd322fcfac17052caff21626ea7c78e2 from qemu
When performing virtual to physical address translation, check the
required privilege level based on the mem_idx rather than the mode in
the hflags. This will allow EVA loads & stores to operate safely only on
user memory from kernel mode.
For the cases where the mmu_idx doesn't need to be overridden
(mips_cpu_get_phys_page_debug() and cpu_mips_translate_address()), we
calculate the required mmu_idx using cpu_mmu_index(). Note that this
only tests the MIPS_HFLAG_KSU bits rather than MIPS_HFLAG_MODE, so we
don't test the debug mode hflag MIPS_HFLAG_DM any longer. This should be
fine as get_physical_address() only compares against MIPS_HFLAG_UM and
MIPS_HFLAG_SM, neither of which should get set by compute_hflags() when
MIPS_HFLAG_DM is set.
Backports commit 9fbf4a58c90183b30bb2c8ad971ccce7e6716a16 from qemu
Add support for the CP0_EBase.WG bit, which allows upper bits to be
written (bits 31:30 on MIPS32, or bits 63:30 on MIPS64), along with the
CP0_Config5.CV bit to control whether the exception vector for Cache
Error exceptions is forced into KSeg1.
This is necessary on MIPS32 to support Segmentation Control and Enhanced
Virtual Addressing (EVA) extensions (where KSeg1 addresses may not
represent an unmapped uncached segment).
It is also useful on MIPS64 to allow the exception base to reside in
XKPhys, and possibly out of range of KSEG0 and KSEG1.
Backports commit 74dbf824a1313b6064bbebb981a7440951d70896 from qemu
There is no need to invalidate any shadow TLB entries when the ASID
changes or when access to one of the 64-bit segments has been disabled,
since doing so doesn't reveal to software whether any TLB entries have
been evicted into the shadow half of the TLB.
Therefore weaken the tlb flushes in these cases to only flush the QEMU
TLB.
Backports commit 9658e4c342e6ae0d775101f8f6bb6efb16789af1 from qemu
This patch fixes setting DExcCode field of CP0 Debug register
when SDBBP instruction is executed. According to EJTAG specification,
this field must be set to the value 9 (Bp).
Backports commit c6c2c0fc32362ba234ae3bdad1a55c2d6aefaa12 from qemu
static code analyzer complain:
target/mips/helper.c:453:5: warning: Function call argument is an uninitialized value
qemu_log_mask(CPU_LOG_MMU,
^~~~~~~~~~~~~~~~~~~~~~~~~~
'physical' and 'prot' are uninitialized if 'ret' is not TLBRET_MATCH.
Backports commit def74c0cf05722b2e502d4b4f1219966c5b0cbd3 from qemu
We've currently got 18 architectures in QEMU, and thus 18 target-xxx
folders in the root folder of the QEMU source tree. More architectures
(e.g. RISC-V, AVR) are likely to be included soon, too, so the main
folder of the QEMU sources slowly gets quite overcrowded with the
target-xxx folders.
To disburden the main folder a little bit, let's move the target-xxx
folders into a dedicated target/ folder, so that target-xxx/ simply
becomes target/xxx/ instead.
Backports commit fcf5ef2ab52c621a4617ebbef36bf43b4003f4c0 from qemu
