This renames some helpers to reflect better what they do.
This should cause no behavioural change.
Backports commit 8629d3fcb77e9775e44d9051bad0fb5187925eae from qemu
FlatView's will be shared between AddressSpace's and subpage_t
and MemoryRegionSection cannot store AS anymore, hence this change.
In particular, for:
typedef struct subpage_t {
MemoryRegion iomem;
- AddressSpace *as;
+ FlatView *fv;
hwaddr base;
uint16_t sub_section[];
} subpage_t;
struct MemoryRegionSection {
MemoryRegion *mr;
- AddressSpace *address_space;
+ FlatView *fv;
hwaddr offset_within_region;
Int128 size;
hwaddr offset_within_address_space;
bool readonly;
};
This should cause no behavioural change.
Backports commit 166206845f7fd75e720e6feea0bb01957c8da07f from qemu
As we are going to share FlatView's between AddressSpace's,
and AddressSpaceDispatch is a structure to perform quick lookup
in FlatView, this moves ASD to FlatView.
After previosly open coded ASD rendering, we can also remove
as->next_dispatch as the new FlatView pointer is stored
on a stack and set to an AS atomically.
flatview_destroy() is executed under RCU instead of
address_space_dispatch_free() now.
This makes mem_begin/mem_commit to work with ASD and mem_add with FV
as later on mem_add will be taking FV as an argument anyway.
This should cause no behavioural change.
Backports commit 66a6df1dc6d5b28cc3e65db0d71683fbdddc6b62 from qemu
Convert all machines to use DEFINE_MACHINE() instead of QEMUMachine
automatically using a script.
Backports commit e264d29de28c5b0be3d063307ce9fb613b427cc3 from qemu
Since f3218a8 ("softfloat: add floatx80 constants")
floatx80_infinity is defined but never used.
This patch updates floatx80 functions to use
this definition.
This allows to define a different default Infinity
value on m68k: the m68k FPU defines infinity with
all bits set to zero in the mantissa.
Backports commit 0f605c889ca3fe9744166ad4149d0dff6dacb696 from qemu
Much like recpe the ARM ARM has simplified the pseudo code for the
calculation which is done on a fixed point 9 bit integer maths. So
while adding f16 we can also clean this up to be a little less heavy
on the floating point and just return the fractional part and leave
the calle's to do the final packing of the result.
Backports commit d719cbc7641991d16b891ffbbfc3a16a04e37b9a from qemu
Also removes a load of symbols that seem unnecessary from the header_gen script
It looks like the ARM ARM has simplified the pseudo code for the
calculation which is done on a fixed point 9 bit integer maths. So
while adding f16 we can also clean this up to be a little less heavy
on the floating point and just return the fractional part and leave
the calle's to do the final packing of the result.
Backports commit 5eb70735af1c0b607bf2671a53aff3710cc1672f from qemu
This is a little bit of a departure from softfloat's original approach
as we skip the estimate step in favour of a straight iteration. There
is a minor optimisation to avoid calculating more bits of precision
than we need however this still brings a performance drop, especially
for float64 operations.
Backports commit c13bb2da9eedfbc5886c8048df1bc1114b285fb0 from qemu
The compare function was already expanded from a macro. I keep the
macro expansion but move most of the logic into a compare_decomposed.
Backports commit 0c4c90929143a530730e2879204a55a30bf63758 from qemu
Let's do the same re-factor treatment for minmax functions. I still
use the MACRO trick to expand but now all the checking code is common.
Backports commit 89360067071b1844bf745682e18db7dde74cdb8d from qemu
This is one of the simpler manipulations you could make to a floating
point number.
Backports commit 0bfc9f195209593e91a98cf2233753f56a2e5c02 from qemu
These are considerably simpler as the lower order integers can just
use the higher order conversion function. As the decomposed fractional
part is a full 64 bit rounding and inexact handling comes from the
pack functions.
Backports commit c02e1fb80b553d47420f7492de4bc590c2461a86 from qemu
We share the common int64/uint64_pack_decomposed function across all
the helpers and simply limit the final result depending on the final
size.
Backports commit ab52f973a504f8de0c5df64631ba4caea70a7d9e from qemu
We can now add float16_round_to_int and use the common round_decomposed and
canonicalize functions to have a single implementation for
float16/32/64 round_to_int functions.
Backports commit dbe4d53a590f5689772b683984588b3cf6df163e from qemu
We can now add float16_muladd and use the common decompose and
canonicalize functions to have a single implementation for
float16/32/64 muladd functions.
Backports commit d446830a3aac33e7221e361dad3ab1e1892646cb from qemu
We can now add float16_div and use the common decompose and
canonicalize functions to have a single implementation for
float16/32/64 versions.
Backports commit cf07323d494f4bc225e405688c2e455c3423cc40 from qemu
We can now add float16_mul and use the common decompose and
canonicalize functions to have a single implementation for
float16/32/64 versions.
Backports commit 74d707e2cc1e406068acad8e5559cd2584b1073a from qemu
We can now add float16_add/sub and use the common decompose and
canonicalize functions to have a single implementation for
float16/32/64 add and sub functions.
Backports commit 6fff216769cf7eaa3961c85dee7a72838696d365 from qemu
This will be required when expanding the MINMAX() macro for 16
bit/half-precision operations.
Backports commit 210cbd4910ae9e41e0a1785b96890ea2c291b381 from qemu
compare_litqobj_to_qobj() lacks a qlit_ prefix. Moreover, "compare"
suggests -1, 0, +1 for less than, equal and greater than. The
function actually returns non-zero for equal, zero for unequal.
Rename to qlit_equal_qobject().
Its return type will be cleaned up in the next patch.
Backports commit 60cc2eb7afd40b9cbaa35a5e0b54f365ac6e49f1 from qemu
This implements emulation of the new SM4 instructions that have
been added as an optional extension to the ARMv8 Crypto Extensions
in ARM v8.2.
Backports commit b6577bcd251ca0d57ae1de149e3c706b38f21587 from qemu
This implements emulation of the new SM3 instructions that have
been added as an optional extension to the ARMv8 Crypto Extensions
in ARM v8.2.
Backports commit 80d6f4c6bbb718f343a832df8dee15329cc7686c from qemu
This implements emulation of the new SHA-512 instructions that have
been added as an optional extensions to the ARMv8 Crypto Extensions
in ARM v8.2.
Backports commit 90b827d131812d7f0a8abb13dba1942a2bcee821 from qemu
The x86 vector instruction set is extremely irregular. With newer
editions, Intel has filled in some of the blanks. However, we don't
get many 64-bit operations until SSE4.2, introduced in 2009.
The subsequent edition was for AVX1, introduced in 2011, which added
three-operand addressing, and adjusts how all instructions should be
encoded.
Given the relatively narrow 2 year window between possible to support
and desirable to support, and to vastly simplify code maintainence,
I am only planning to support AVX1 and later cpus.
Backports commit 770c2fc7bb70804ae9869995fd02dadd6d7656ac from qemu
Use dup to convert a non-constant scalar to a third vector.
Add addition, multiplication, and logical operations with an immediate.
Add addition, subtraction, multiplication, and logical operations with
a non-constant scalar. Allow for the front-end to build operations in
which the scalar operand comes first.
Backports commit 22fc3527034678489ec554e82fd52f8a7f05418e from qemu
No vector ops as yet. SSE only has direct support for 8- and 16-bit
saturation; handling 32- and 64-bit saturation is much more expensive.
Backports commit f49b12c6e6a75a5bd109bcbbda072b24e5fb8dfd from qemu
Opcodes are added for scalar and vector shifts, but considering the
varied semantics of these do not expose them to the front ends. Do
go ahead and provide them in case they are needed for backend expansion.
Backports commit d0ec97967f940bbc11dced83422b39c224127f1e from qemu
With no fixed array allocation, we can't overflow a buffer.
This will be important as optimizations related to host vectors
may expand the number of ops used.
Use QTAILQ to link the ops together.
Backports commit 15fa08f8451babc88d733bd411d4c94976f9d0f8 from qemu
This was never used since its introduction in commit
196ea13104f8 ("memory: Add global-locking property to memory
regions").
Backports commit e2fbe20851ceec5ccd7b539a89db0420393fb85d from qemu
Implement the TT instruction which queries the security
state and access permissions of a memory location.
Backports commit 5158de241b0fb344a6c948dfcbc4e611ab5fafbe from qemu
In the v7M architecture, there is an invariant that if the CPU is
in Handler mode then the CONTROL.SPSEL bit cannot be nonzero.
This in turn means that the current stack pointer is always
indicated by CONTROL.SPSEL, even though Handler mode always uses
the Main stack pointer.
In v8M, this invariant is removed, and CONTROL.SPSEL may now
be nonzero in Handler mode (though Handler mode still always
uses the Main stack pointer). In preparation for this change,
change how we handle this bit: rename switch_v7m_sp() to
the now more accurate write_v7m_control_spsel(), and make it
check both the handler mode state and the SPSEL bit.
Note that this implicitly changes the point at which we switch
active SP on exception exit from before we pop the exception
frame to after it.
Backports commit de2db7ec894f11931932ca78cd14a8d2b1389d5b from qemu
We have object_get_objects_root() to keep user created objects, however
no place for objects that will be used internally. Create such a
container for internal objects.
Backports commit 7c47c4ead75d0b733ee8f2f51fd1de0644cc1308 from qemu
Replace the USE_DIRECT_JUMP ifdef with a TCG_TARGET_HAS_direct_jump
boolean test. Replace the tb_set_jmp_target1 ifdef with an unconditional
function tb_target_set_jmp_target.
While we're touching all backends, add a parameter for tb->tc_ptr;
we're going to need it shortly for some backends.
Move tb_set_jmp_target and tb_add_jump from exec-all.h to cpu-exec.c.
Backports commit a85833933628384d74ec412024d55cf012640287 from qemu
Define a new MachineClass field ignore_memory_transaction_failures.
If this is flag is true then the CPU will ignore memory transaction
failures which should cause the CPU to take an exception due to an
access to an unassigned physical address; the transaction will
instead return zero (for a read) or be ignored (for a write). This
should be set only by legacy board models which rely on the old
RAZ/WI behaviour for handling devices that QEMU does not yet model.
New board models should instead use "unimplemented-device" for all
memory ranges where the guest will attempt to probe for a device that
QEMU doesn't implement and a stub device is required.
We need this for ARM boards, where we're about to implement support for
generating external aborts on memory transaction failures. Too many
of our legacy board models rely on the RAZ/WI behaviour and we
would break currently working guests when their "probe for device"
code provoked an external abort rather than a RAZ.
Backports commit ed860129acd3fcd0b1e47884e810212aaca4d21b from qemu
Implement the BXNS v8M instruction, which is like BX but will do a
jump-and-switch-to-NonSecure if the branch target address has bit 0
clear.
This is the first piece of code which implements "switch to the
other security state", so the commit also includes the code to
switch the stack pointers around, which is the only complicated
part of switching security state.
BLXNS is more complicated than just "BXNS but set the link register",
so we leave it for a separate commit.
Backports commit fb602cb726b3ebdd01ef3b1732d74baf9fee7ec9 from qemu
Rename memory_region_init_rom() to memory_region_init_rom_nomigrate()
and memory_region_init_rom_device() to
memory_region_init_rom_device_nomigrate().
Backports commit b59821a95bd1d7cb4697fd7748725c910582e0e7 from qemu
Rename memory_region_init_ram() to memory_region_init_ram_nomigrate().
This leaves the way clear for us to provide a memory_region_init_ram()
which does handle migration.
Backports commit 1cfe48c1ce219b60a9096312f7a61806fae64ab3 from qemu
Commit 1f5c00cfdb8114c ("qom/cpu: move tlb_flush to cpu_common_reset")
moved the call to tlb_flush() from the target-specific reset handlers
into the common code qom/cpu.c file, and protected the call with
"#ifdef CONFIG_SOFTMMU" to avoid that it is called for linux-user
only targets. But since qom/cpu.c is common code, CONFIG_SOFTMMU is
*never* defined here, so the tlb_flush() was simply never executed
anymore. Fix it by introducing a wrapper for tlb_flush() in a file
that is re-compiled for each target, i.e. in translate-all.c.
Backports commit 2cd53943115be5118b5b2d4b80ee0a39c94c4f73 from qemu
Allocating an arbitrarily-sized array of tbs results in either
(a) a lot of memory wasted or (b) unnecessary flushes of the code
cache when we run out of TB structs in the array.
An obvious solution would be to just malloc a TB struct when needed,
and keep the TB array as an array of pointers (recall that tb_find_pc()
needs the TB array to run in O(log n)).
Perhaps a better solution, which is implemented in this patch, is to
allocate TB's right before the translated code they describe. This
results in some memory waste due to padding to have code and TBs in
separate cache lines--for instance, I measured 4.7% of padding in the
used portion of code_gen_buffer when booting aarch64 Linux on a
host with 64-byte cache lines. However, it can allow for optimizations
in some host architectures, since TCG backends could safely assume that
the TB and the corresponding translated code are very close to each
other in memory. See this message by rth for a detailed explanation:
https://lists.gnu.org/archive/html/qemu-devel/2017-03/msg05172.html
Subject: Re: GSoC 2017 Proposal: TCG performance enhancements
Backports commit 6e3b2bfd6af488a896f7936e99ef160f8f37e6f2 from qemu
Instead of exporting goto_ptr directly to TCG frontends, export
tcg_gen_lookup_and_goto_ptr(), which calls goto_ptr with the pointer
returned by the lookup_tb_ptr() helper. This is the only use case
we have for goto_ptr and lookup_tb_ptr, so having this function is
very convenient. Furthermore, it trivially allows us to avoid calling
the lookup helper if goto_ptr is not implemented by the backend.
Backports commit cedbcb01529cb6cf9a2289cdbebbc63f6149fc18 from qemu
We know there will be cases where MTTCG won't work until additional work
is done in the front/back ends to support. It will however be useful to
be able to turn it on.
As a result MTTCG will default to off unless the combination is
supported. However the user can turn it on for the sake of testing.
Backports commit 8d4e9146b3568022ea5730d92841345d41275d66 from qemu
In BE32 mode, sub-word size watchpoints can fail to trigger because the
address of the access is adjusted in the opcode helpers before being
compared with the watchpoint registers. This patch reverses the address
adjustment before performing the comparison with the help of a new CPUClass
hook.
This version of the patch augments and tidies up comments a little.
Backports commit 40612000599e52e792d23c998377a0fa429c4036 from qemu
The number of actual invocations of ctpop itself does not warrent
an opcode, but it is very helpful for POWER7 to use in generating
an expansion for ctz.
Backports commit a768e4e99247911f00c5c0267c12d4e207d5f6cc from qemu
The number of actual invocations does not warrent an opcode,
and the backends generating it. But at least we can eliminate
redundant helpers.
Backports commit 086920c2c8008f125fd38781072fa25c3ad158ea from qemu
While we don't require a new opcode, it is handy to have an expander
that knows the first source is zero.
Backports commit 07cc68d52852bf47dea7c402b46ddd28248d4212 from qemu
Adds tcg_gen_extract_* and tcg_gen_sextract_* for extraction of
fixed position bitfields, much like we already have for deposit.
Backports commit 7ec8bab3deae643b1ce579c2d65a244f30708330 from qemu
This patch introduces a helper to query the iotlb entry for a
possible iova. This will be used by later device IOTLB API to enable
the capability for a dataplane (e.g vhost) to query the IOTLB.
Backports commit 052c8fa9983f553fdfa0d61034774070dd639c2b from qemu
Device models often have to perform multiple access to a single
memory region that is known in advance, but would to use "DMA-style"
functions instead of address_space_map/unmap. This can happen
for example when the data has to undergo endianness conversion.
Introduce a new data structure to cache the result of
address_space_translate without forcing usage of a host address
like address_space_map does.
Backports commit 1f4e496e1fc2eb6c8bf377a0f9695930c380bfd3 from qemu
This multiply has one signed input and one unsigned input,
producing the full double-width result.
Backports commit 5087abfb7dfd1d368ae6939420057036b4d8e509 from qemu
At the same time, fix a problem with stqf_asi, when
a write might access two pages.
Backports commit f939ffe5a022a8798824e2720ed5a14186fca6b6 from qemu
Several helpers call helper_raise_exception directly, which requires
in turn that their callers have performed save_state. The new function
allows a TCG return address to be passed in so that we can restore
PC + NPC + flags data from that.
This fixes a bug in the usage of helper_check_align, whose callers had
not been calling save_state. It fixes another bug in which the divide
helpers used GETPC at a level other than the direct callee from TCG.
This allows the translator to avoid save_state prior to SAVE, RESTORE,
and FLUSHW instructions.
Backports commit 2f9d35fc4006122bad33f9ae3e2e51d2263e98ee from qemu
Allow qemu to build on 32-bit hosts without 64-bit atomic ops.
Even if we only allow 32-bit hosts to multi-thread emulate 32-bit
guests, we still need some way to handle the 32-bit guest using a
64-bit atomic operation. Do so by dropping back to single-step.
Backports commit df79b996a7b21c6ea7847f7927a2e1a294b86c72 from qemu
Force the use of cmpxchg16b on x86_64.
Wikipedia suggests that only very old AMD64 (circa 2004) did not have
this instruction. Further, it's required by Windows 8 so no new cpus
will ever omit it.
If we truely care about these, then we could check this at startup time
and then avoid executing paths that use it.
Backports commit 7ebee43ee3e2fcd7b5063058b7ef74bc43216733 from qemu
Add all of cmpxchg, op_fetch, fetch_op, and xchg.
Handle both endian-ness, and sizes up to 8.
Handle expanding non-atomically, when emulating in serial.
Backports commit c482cb117cc418115ca9c6d21a7a2315414c0a40 from qemu
Probe for whether the specified guest write access is permitted.
If it is not permitted then an exception will be taken in the same
way as if this were a real write access (and we will not return).
Otherwise the function will return, and there will be a valid
entry in the TLB for this access.
Backports commit 3b4afc9e75ab1a95f33e41f462921093f8a109c4 from qemu
When we cannot emulate an atomic operation within a parallel
context, this exception allows us to stop the world and try
again in a serial context.
Backports commit fdbc2b5722f6092e47181a947c90fd4bdcc1c121 from qemu
Also backports parts of commit 02d57ea115b7669f588371c86484a2e8ebc369be
The QmpOutputVisitor has no direct dependency on QMP. It is
valid to use it anywhere that one wants a QObject. Rename it
to better reflect its functionality as a generic QAPI
to QObject converter.
The commit before previous renamed the files, this one renames C
identifiers.
Backports commit 7d5e199ade76c53ec316ab6779800581bb47c50a from qemu
The QmpInputVisitor has no direct dependency on QMP. It is
valid to use it anywhere that one has a QObject. Rename it
to better reflect its functionality as a generic QObject
to QAPI converter.
The previous commit renamed the files, this one renames C identifiers.
Backports commit 09e68369a88d7de0f988972bf28eec1b80cc47f9 from qemu
Support target CPUs having a page size which isn't knownn
at compile time. To use this, the CPU implementation should:
* define TARGET_PAGE_BITS_VARY
* not define TARGET_PAGE_BITS
* define TARGET_PAGE_BITS_MIN to the smallest value it
might possibly want for TARGET_PAGE_BITS
* call set_preferred_target_page_bits() in its realize
function to indicate the actual preferred target page
size for the CPU (and report any error from it)
In CONFIG_USER_ONLY, the CPU implementation should continue
to define TARGET_PAGE_BITS appropriately for the guest
OS page size.
Machines which want to take advantage of having the page
size something larger than TARGET_PAGE_BITS_MIN must
set the MachineClass minimum_page_bits field to a value
which they guarantee will be no greater than the preferred
page size for any CPU they create.
Note that changing the target page size by setting
minimum_page_bits is a migration compatibility break
for that machine.
For debugging purposes, attempts to use TARGET_PAGE_SIZE
before it has been finally confirmed will assert.
Backports commit 20bccb82ff3ea09bcb7c4ee226d3160cab15f7da from qemu
Remove L1 page mapping table properties computing
statically using macros which is dependent on
TARGET_PAGE_BITS. Drop macros V_L1_SIZE, V_L1_SHIFT,
V_L1_BITS macros and replace with variables which are
computed at early stage of VM boot.
Removing dependency can help to make TARGET_PAGE_BITS
dynamic.
Backports commit 66ec9f49399f0a9fa13ee77c472caba0de2773fc from qemu
This commit introduces the TCGOpcode for memory barrier instruction.
This opcode takes an argument which is the type of memory barrier
which should be generated.
Backports commit f65e19bc2c9e8358e634d309606144ac2a3c2936 from qemu
Setting skip_dump on a MemoryRegion allows us to modify one specific
code path, but the restriction we're trying to address encompasses
more than that. If we have a RAM MemoryRegion backed by a physical
device, it not only restricts our ability to dump that region, but
also affects how we should manipulate it. Here we recognize that
MemoryRegions do not change to sometimes allow dumps and other times
not, so we replace setting the skip_dump flag with a new initializer
so that we know exactly the type of region to which we're applying
this behavior.
Backports commit ca83f87a66d19fdaabf23d4f5ebb49396fe232c1 from qemu
Rather than rely on recursion during the middle of register allocation,
lower indirect registers to loads and stores off the indirect base into
plain temps.
For an x86_64 host, with sufficient registers, this results in identical
code, modulo the actual register assignments.
For an i686 host, with insufficient registers, this means that temps can
be (temporarily) spilled to the stack in order to satisfy an allocation.
This as opposed to the possibility of not being able to spill, to allocate
a register for the indirect base, in order to perform a spill.
Backports commit 5a18407f55ade924aa6397c9a043a9ffd59645fe from qemu
By arranging for explicit writes to cpu_fsr after floating point
operations, we are able to mark the helpers as not writing to
tcg globals, which means that we don't need to invalidate the
integer register set across said calls.
Backports commit 7385aed20db5d83979f683b9d0048674411e963c from qemu
Provide a new helper function memory_region_init_rom() for memory
regions which are read-only (and unlike those created by
memory_region_init_rom_device() don't have special behaviour
for writes). This has the same behaviour as calling
memory_region_init_ram() and then memory_region_set_readonly()
(which is what we do today in boards with pure ROMs) but is a
more easily discoverable API for the purpose.
Backports commit a1777f7f6462c66e1ee6e98f0d5c431bfe988aa5 from qemu
Add an API object_type_get_size(const char *typename) that returns the
instance_size of the give typename.
Backports commit 3f97b53a682d2595747c926c00d78b9d406f1be0 from qemu
The function cpu_resume_from_signal() is now always called with a
NULL puc argument, and is rather misnamed since it is never called
from a signal handler. It is essentially forcing an exit to the
top level cpu loop but without raising any exception, so rename
it to cpu_loop_exit_noexc() and drop the useless unused argument.
Backports commit 6886b98036a8f8f5bce8b10756ce080084cef11b from qemu
Let users of qemu_get_ram_ptr and qemu_ram_ptr_length pass in an
address that is relative to the MemoryRegion. This basically means
what address_space_translate returns.
Because the semantics of the second parameter change, rename the
function to qemu_map_ram_ptr.
Backports commit 0878d0e11ba8013dd759c6921cbf05ba6a41bd71 from qemu
Move the old qemu_ram_addr_from_host to memory_region_from_host and
make it return an offset within the region. For qemu_ram_addr_from_host
return the ram_addr_t directly, similar to what it was before
commit 1b5ec23 ("memory: return MemoryRegion from qemu_ram_addr_from_host",
2013-07-04).
Backports commit 07bdaa4196b51bc7ffa7c3f74e9e4a9dc8a7966a from qemu
Remove direct uses of ram_addr_t and optimize memory_region_{get,set}_fd
now that a MemoryRegion knows its RAMBlock directly.
Backports commit 4ff87573df3606856a92c14eef3393a63d736d11 from qemu
To prepare for multi-arch, cputlb.c should only have awareness of one
single architecture. This means it should not have access to the full
CPU lists which may be heterogeneous. Instead, push the CPU_LOOP() up
to the one and only caller in exec.c.
Backports commit 9a13565d52bfd321934fb44ee004bbaf5f5913a8 from qemu
There is no particular reason to keep these functions in the header.
Suggested by Paolo.
Backports commit 99affd1d5bd4e396ecda50e53dfbc5147fa1313d from qemu
Not only it makes sense, but it gets rid of checkpatch warning:
WARNING: consider using qemu_strtosz in preference to strtosz
Also remove get rid of tabs to please checkpatch.
Backports commit 4677bb40f809394bef5fa07329dea855c0371697 from qemu
This patch replaces get_ticks_per_sec() calls with the macro
NANOSECONDS_PER_SECOND. Also, as there are no callers, get_ticks_per_sec()
is then removed. This replacement improves the readability and
understandability of code.
For example,
timer_mod(fdctrl->result_timer,
qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + (get_ticks_per_sec() / 50));
NANOSECONDS_PER_SECOND makes it obvious that qemu_clock_get_ns
matches the unit of the expression on the right side of the plus.
Backports commit 73bcb24d932912f8e75e1d88da0fc0ac6d4bce78 from qemu
Starting with the ARMv7 Virtualization Extensions, the A32 and T32
instruction sets provide instructions "MSR (banked)" and "MRS
(banked)" which can be used to access registers for a mode other
than the current one:
* R<m>_<mode>
* ELR_hyp
* SPSR_<mode>
Implement the missing instructions.
Backports commit 8bfd0550be821cf27d71444e2af350de3c3d2ee3 from qemu
