Note that env->active_tc.PC is removed from the qemu_log as that value
is garbage. The PC isn't recovered until cpu_restore_state, called from
cpu_loop_exit_restore, called from do_raise_exception_err.
Backports commit 931d019f5b2e7bbacb162869497123be402ddd86 from qemu
Completely rewrite conditional stores handling. Use cmpxchg.
This eliminates need for separate implementations of SC instruction
emulation for user and system emulation.
Backports commit 33a07fa2db66376e6ee780d4a8b064dc5118cf34 from qemu
Do only virtual addresses comaprisons in LL/SC sequence emulations.
Until this patch, physical addresses had been compared in SC part of
LL/SC sequence, even though such comparisons could be avoided. Getting
rid of them allows throwing away SC helpers and having common SC
implementations in user and system mode, avoiding the need for two
separate implementations selected by #ifdef CONFIG_USER_ONLY.
Correct guest software should not rely on LL/SC if they accesses the
same physical address via different virtual addresses or if page
mapping gets changed between LL/SC due to manipulating TLB entries.
MIPS Instruction Set Manual clearly says that an RMW sequence must
use the same address in the LL and SC (virtual address, physical
address, cacheability and coherency attributes must be identical).
Otherwise, the result of the SC is not predictable. This patch takes
advantage of this fact and removes the virtual->physical address
translation from SC helper.
lladdr served as Coprocessor 0 LLAddr register which captures physical
address of the most recent LL instruction, and also lladdr was used
for comparison with following SC physical address. This patch changes
the meaning of lladdr - now it will only keep the virtual address of
the most recent LL. Additionally, CP0_LLAddr field is introduced which
is the actual Coperocessor 0 LLAddr register that guest can access.
Backports commit c7c7e1e9a5e3f0a8a1dbff6e4ccfd21c2dc9f845 from qemu
Implement hardware page table walker. This implementation is
limiter only to MIPS32.
Backports commit 074cfcb4daedf59ccbbbc83c24eee80e0e8f4c71 from qemu
Add PWCtl register (CP0 Register 5, Select 6).
The PWCtl register configures hardware page table walking for TLB
refills.
This register is required for the hardware page walker feature. It
exists only if Config3 PW bit is set to 1. It contains following
fields:
PWEn (31) - Hardware Page Table walker enable
PWDirExt (30) - If 1, 4-th level implemented (MIPS64 only)
XK (28) - If 1, walker handles xkseg (MIPS64 only)
XS (27) - If 1, walker handles xsseg (MIPS64 only)
XU (26) - If 1, walker handles xuseg (MIPS64 only)
DPH (7) - Dual Page format of Huge Page support
HugePg (6) - Huge Page PTE supported in Directory levels
PSn (5..0) - Bit position of PTEvld in Huge Page PTE
Backports commit 103be64c26c166f12b3e1308edadef3443723ff1 from qemu
Add PWSize register (CP0 Register 5, Select 7).
The PWSize register configures hardware page table walking for TLB
refills.
This register is required for the hardware page walker feature. It
exists only if Config3 PW bit is set to 1. It contains following
fields:
BDW (37..32) Base Directory index width (MIPS64 only)
GDW (29..24) Global Directory index width
UDW (23..18) Upper Directory index width
MDW (17..12) Middle Directory index width
PTW (11..6 ) Page Table index width
PTEW ( 5..0 ) Left shift applied to the Page Table index
Backports commit 20b28ebc49945583d7191b57755cfd92433de9ff from qemu
Add PWField register (CP0 Register 5, Select 6).
The PWField register configures hardware page table walking for TLB
refills.
This register is required for the hardware page walker feature. It
exists only if Config3 PW bit is set to 1. It contains following
fields:
MIPS64:
BDI (37..32) - Base Directory index
GDI (29..24) - Global Directory index
UDI (23..18) - Upper Directory index
MDI (17..12) - Middle Directory index
PTI (11..6 ) - Page Table index
PTEI ( 5..0 ) - Page Table Entry shift
MIPS32:
GDW (29..24) - Global Directory index
UDW (23..18) - Upper Directory index
MDW (17..12) - Middle Directory index
PTW (11..6 ) - Page Table index
PTEW ( 5..0 ) - Page Table Entry shift
Backports commit fa75ad1459f4f6abbeb6d375a812dfad61320f58 from qemu
Added a helper for ROTX based on the pseudocode from the
architecture spec. This instraction was not present in previous
MIPS instruction sets.
Backports commit e222f5067269392af489731221750976d0cf3c05 from qemu
Fix to raise a Reserved Instruction exception when given fs is not
available from CTC1.
Backports commit f48a2cb21824217a61ec7be797860a0702e5325c from qemu
The MC68040 MMU provides the size of the access that
triggers the page fault.
This size is set in the Special Status Word which
is written in the stack frame of the access fault
exception.
So we need the size in m68k_cpu_unassigned_access() and
m68k_cpu_handle_mmu_fault().
To be able to do that, this patch modifies the prototype of
handle_mmu_fault handler, tlb_fill() and probe_write().
do_unassigned_access() already includes a size parameter.
This patch also updates handle_mmu_fault handlers and
tlb_fill() of all targets (only parameter, no code change).
Backports commit 98670d47cd8d63a529ff230fd39ddaa186156f8c from qemu
no logical change, only code movement (and fix a comment typo).
Backports commit 26aa3d9aecbb6fe9bce808a1d127191bdf3cc3d2 from qemu
Also backports commit 5502b66fc7d0bebd08b9b7017cb7e8b5261c3a2d
The optional segmentation control registers CP0_SegCtl0, CP0_SegCtl1 &
CP0_SegCtl2 control the behaviour and required privilege of the legacy
virtual memory segments.
Add them to the CP0 interface so they can be read and written when
CP0_Config3.SC=1, and initialise them to describe the standard legacy
layout so they can be used in future patches regardless of whether they
are exposed to the guest.
Backports commit cec56a733dd2c3fa81dbedbecf03922258747f7d from qemu
The segmentation control feature allows a legacy memory segment to
become unmapped uncached at error level (according to CP0_Status.ERL),
and in fact the user segment is already treated in this way by QEMU.
Add a new MMU mode for this state so that QEMU's mappings don't persist
between ERL=0 and ERL=1.
Backports commit 42c86612d507c2a8789f2b8d920a244693c4ef7b from qemu
The MIPS mmu_idx is sometimes calculated from hflags without an env
pointer available as cpu_mmu_index() requires.
Create a common hflags_mmu_index() for the purpose of this calculation
which can operate on any hflags, not just with an env pointer, and
update cpu_mmu_index() itself and gen_intermediate_code() to use it.
Also update debug_post_eret() and helper_mtc0_status() to log the MMU
mode with the status change (SM, UM, or nothing for kernel mode) based
on cpu_mmu_index() rather than directly testing hflags.
This will also allow the logic to be more easily updated when a new MMU
mode is added.
Backports commit b0fc6003224543d2bdb172eca752656a6223e4a1 from qemu
Add CP0.ErrCtl register with WST, SPR and ITC bits. In 34K and interAptiv
processors these bits are used to enable CACHE instruction access to
different arrays. When WST=0, SPR=0 and ITC=1 the CACHE instruction will
access ITC tag values.
Generally we do not model caches and we have been treating the CACHE
instruction as NOP. But since CACHE can operate on ITC Tags new
MIPS_HFLAG_ITC_CACHE hflag is introduced to generate the helper only when
CACHE is in the ITC Access mode.
Backports commit 0d74a222c27e26fc40f4f6120c61c3f9ceaa3776 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
Writing specific TLB entries with TLBWI flushes shadow TLB entries
unless an existing entry is having its access permissions upgraded. This
is necessary as software would from then on expect the previous mapping
in that entry to no longer be in effect (even if QEMU has quietly
evicted it to the shadow TLB on a TLBWR).
However it won't do this if only EHINV, XI, or RI bits have been set,
even if that results in a reduction of permissions, so add the necessary
checks to invoke the flush when these bits are set.
Backports commit eff6ff9431aa9776062a5f4a08d1f6503ca9995a 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
