VFIO virtualizes MSIX table for the guest but not mapping the part of
a BAR which contains an MSIX table. Since vfio_mmap_bar() mmaps chunks
before and after the MSIX table, they have to be aligned to the host
page size which may be TARGET_PAGE_MASK (4K) or 64K in case of PPC64.
This fixes boundaries calculations to use the real host page size.
Without the patch, the chunk before MSIX table may overlap with the MSIX
table and mmap will fail in the host kernel. The result will be serious
slowdown as the whole BAR will be emulated by QEMU.
There is a HOST_PAGE_ALIGN macro which makes sense for KVM accelerator
but it uses qemu_host_page_size/qemu_host_page_mask which initialized
for TCG only.
This moves qemu_host_page_size/qemu_host_page_mask initialization from
TCG's page_init() and adds a call for it from kvm_init().
Alex Williamson [Thu, 16 Jan 2014 16:22:07 +0000 (09:22 -0700)]
vfio-pci: Fail initfn on DMA mapping errors
The vfio-pci initfn will currently succeed even if DMA mappings fail.
A typical reason for failure is if the user does not have sufficient
privilege to lock all the memory for the guest. In this case, the
device gets attached, but can only access a portion of guest memory
and is extremely unlikely to work.
DMA mappings are done via a MemoryListener, which provides no direct
error return path. We therefore stuff the errno into our container
structure and check for error after registration completes. We can
also test for mapping errors during runtime, but our only option for
resolution at that point is to kill the guest with a hw_error.
Alex Williamson [Thu, 16 Jan 2014 16:22:07 +0000 (09:22 -0700)]
vfio: Filter out bogus mappings
Since 57271d63 we now see spurious mappings with the upper bits set
if 64bit PCI BARs are sized while enabled. The guest writes a mask
of 0xffffffff to the lower BAR to size it, then restores it, then
writes the same mask to the upper BAR resulting in a spurious BAR
mapping into the last 4G of the 64bit address space. Most
architectures do not support or make use of the full 64bits address
space for PCI BARs, so we filter out mappings with the high bit set.
Long term, we probably need to think about vfio telling us the
address width limitations of the IOMMU.
Bandan Das [Wed, 15 Jan 2014 17:11:52 +0000 (10:11 -0700)]
vfio: Do not reattempt a failed rom read
During lazy rom loading, if rom read fails, and the
guest attempts a read again, vfio will again attempt it.
Add a boolean to prevent this. There could be a case where
a failed rom read might succeed the next time because of
a device reset or such, but it's best to exclude unpredictable
behavior
Bandan Das [Wed, 15 Jan 2014 17:11:06 +0000 (10:11 -0700)]
vfio: warn if host device rom can't be read
If the device rom can't be read, report an error to the
user. This alerts the user that the device has a bad
state that is causing rom read failure or option rom
loading has been disabled from the device boot menu
(among other reasons).
Alex Williamson [Wed, 15 Jan 2014 17:07:26 +0000 (10:07 -0700)]
vfio: Destroy memory regions
Somehow this has been lurking for a while; we remove our subregions
from the base BAR and VGA region mappings, but we don't destroy them,
creating a leak and more serious problems when we try to migrate after
removing these devices. Add the trivial bit of final cleanup to
remove these entirely.
error: Don't use error_report() for assertion msgs.
Use fprintf(stderr instead. This removes dependency of libqemuutil.a
on the monitor.
We can further justify this change, in that this code path should only
trigger under a fatal error condition. fprintf-stderr is probably the
appropriate medium as under a fatal error conidition the monitor itself
may be down and out for the count. So assertion failure messages should
go lowest common denominator - straight to stderr.
Fixes the build as reported by Kevin Wolf. Issue debugged and change
suggested by Luiz Capitulino. Issue introduced by 5d24ee70bcbcf578614193526bcd5ed30a8eb16c.
Peter Maydell [Mon, 13 Jan 2014 10:26:16 +0000 (10:26 +0000)]
target-arm: Switch ARMCPUInfo arrays to use terminator entries
Switch the ARMCPUInfo arrays in cpu.c and cpu64.c to use a terminator
entry rather than looping based on ARRAY_SIZE. The latter causes
compile warnings on some versions of gcc if the configure options
happen to result in an empty array.
# gpg: Signature made Mon 13 Jan 2014 09:38:27 AM PST using RSA key ID 5872D723
# gpg: Can't check signature: public key not found
* quintela/tags/migration/20140113: (49 commits)
migration: synchronize memory bitmap 64bits at a time
ram: split function that synchronizes a range
memory: syncronize kvm bitmap using bitmaps operations
memory: move bitmap synchronization to its own function
kvm: refactor start address calculation
kvm: use directly cpu_physical_memory_* api for tracking dirty pages
memory: unfold memory_region_test_and_clear()
memory: split cpu_physical_memory_* functions to its own include
memory: cpu_physical_memory_set_dirty_tracking() should return void
memory: make cpu_physical_memory_reset_dirty() take a length parameter
memory: s/dirty/clean/ in cpu_physical_memory_is_dirty()
memory: cpu_physical_memory_clear_dirty_range() now uses bitmap operations
memory: cpu_physical_memory_set_dirty_range() now uses bitmap operations
memory: use find_next_bit() to find dirty bits
memory: s/mask/clear/ cpu_physical_memory_mask_dirty_range
memory: cpu_physical_memory_get_dirty() is used as returning a bool
memory: make cpu_physical_memory_get_dirty() the main function
memory: unfold cpu_physical_memory_set_dirty_flag()
memory: unfold cpu_physical_memory_set_dirty() in its only user
memory: unfold cpu_physical_memory_clear_dirty_flag() in its only user
...
Juan Quintela [Thu, 10 Oct 2013 09:49:53 +0000 (11:49 +0200)]
memory: make cpu_physical_memory_reset_dirty() take a length parameter
We have an end parameter in all the callers, and this make it coherent
with the rest of cpu_physical_memory_* functions, that also take a
length parameter.
Once here, move the start/end calculation to
tlb_reset_dirty_range_all() as we don't need it here anymore.
Juan Quintela [Tue, 17 Dec 2013 11:12:24 +0000 (12:12 +0100)]
bitmap: use long as index
Move index and size fields from int to long. We need that for
migration. long is 64 bits on sane architectures, and 32bits should
be enough on all the 32bits architectures.
Eduardo Habkost [Thu, 28 Nov 2013 14:01:10 +0000 (12:01 -0200)]
qemu-file: Make a few functions non-static
The QEMUFile code will be moved to qemu-file.c. This will require making
the following functions non-static because they are used by the savevm.c
code:
Matthew Garrett [Mon, 25 Nov 2013 19:42:43 +0000 (14:42 -0500)]
migration: Fix rate limit
The migration thread appears to want to allow writeout to occur at full
speed rather than being rate limited during completion of state saving,
but sets the limit to INT_MAX when xfer_limit is INT64_MAX. This causes
problems if there's more than 2GB of state left to save at this point. It
probably ought to just be INT64_MAX instead.
Zhanghaoyu (A) [Thu, 7 Nov 2013 08:21:23 +0000 (08:21 +0000)]
avoid a bogus COMPLETED->CANCELLED transition
Avoid a bogus COMPLETED->CANCELLED transition.
There is a period of time from the timing of setting COMPLETED state to that of migration thread exits, so during which it's problematic in COMPLETED->CANCELLED transition.
Anthony Liguori [Mon, 13 Jan 2014 01:50:52 +0000 (17:50 -0800)]
Merge remote-tracking branch 'pmaydell/tags/pull-cocoa-20140112' into staging
cocoa queue:
* pass command key to guest when VM has mousegrab
* add .qcow2 to extension list for image load dialog
* fix bugs in code for starting QEMU via image load dialog
* fix resize/redraw interaction
* draw window black if guest hasn't sent anything to screen
* minor style/typo fixes
* add myself as cocoa co-maintainer
# gpg: Signature made Sun 12 Jan 2014 02:45:52 PM PST using RSA key ID 14360CDE
# gpg: Can't check signature: public key not found
* pmaydell/tags/pull-cocoa-20140112:
MAINTAINERS: add myself as cocoa UI co-maintainer
ui/cocoa: Remove stray tabs
ui/cocoa: Draw black rectangle if we have no data yet
ui/cocoa: Redraw at correct size when switching surface
ui/cocoa: Fix code for starting QEMU via image file load dialog
ui/cocoa: Add ".qcow2" to extension list for image load dialog
ui/cocoa: Send warning message to stderr, not stdout
ui/cocoa: Correct typos in comments and variable names
ui/cocoa: Pass command key through to guest when VM has mousegrab
Peter Maydell [Tue, 24 Dec 2013 02:51:47 +0000 (02:51 +0000)]
ui/cocoa: Draw black rectangle if we have no data yet
If our redraw method is called before we have any data from the guest,
then draw a black rectangle rather than leaving the window empty.
This mostly only matters when the guest machine has no framebuffer
device, but it is more in line with the behaviour of other QEMU UIs.
Peter Maydell [Tue, 24 Dec 2013 02:51:46 +0000 (02:51 +0000)]
ui/cocoa: Redraw at correct size when switching surface
If the surface switch involved a resize, we were doing the redraw
at the old size rather than the new, because the update of
screen.width and screen.height was being done after the setFrame
method calls which triggered a redraw. Normally this isn't very
noticeable because typically after the guest triggers the window
resize it also draws something to it, which will in turn cause
us to redraw. However, the combination of a guest which never
draws to the display and a command line setting of a screen size
larger than the default can reveal odd effects.
Move most of the handling of resizes to the top of the method,
and guard it with a check that the surface size actually changed,
to avoid unnecessary operations (including some user visible ones
like "recenter the window on the screen") if the surface is the
same size as the old one.
Peter Maydell [Sun, 8 Dec 2013 22:59:06 +0000 (22:59 +0000)]
ui/cocoa: Fix code for starting QEMU via image file load dialog
Fix a number of bugs in the code for starting QEMU via the image
file load dialog:
* use the actual argv[0] rather than "qemu": this avoids failures to
find BIOS image files caused by not looking in the correct directory
relative to the executable path
* allocate a large enough argv array to NULL terminate it
* use g_strdup(X) rather than g_strdup_printf("%s", X) or
g_strdup_printf(X)
* disable the printing of the simulated command line argument
(which is presumably intended for debug only)
Peter Maydell [Sun, 8 Dec 2013 22:59:05 +0000 (22:59 +0000)]
ui/cocoa: Add ".qcow2" to extension list for image load dialog
Add ".qcow2" to the list of file extensions which are accepted
by the initial disk image load dialog which is displayed if the
user runs QEMU without any command line arguments.
Peter Maydell [Sun, 8 Dec 2013 22:59:02 +0000 (22:59 +0000)]
ui/cocoa: Pass command key through to guest when VM has mousegrab
The guest might want to be able to use the command key for its won
purposes (as command if it is MacOS X, or for the Windows key if
it is a PC guest, for instance). In line with other UI frontends,
pass it through if the guest has mousegrab, and only use it for UI
menu accelerators if not grabbed.
Thanks to John Arbuckle for reporting this problem, helping
us work through what the best solution would be and providing
a patch which was the initial inspiration for this one.
Anthony Liguori [Fri, 10 Jan 2014 19:05:05 +0000 (11:05 -0800)]
Merge remote-tracking branch 'stefanha/block' into staging
* stefanha/block:
commit: Remove unused check
qemu-iotests: Update test cases for commit active
commit: Support commit active layer
block: Add commit_active_start()
mirror: Move base to MirrorBlockJob
mirror: Don't close target
qemu-iotests: drop duplicate virtio-blk initialization failure
vmdk: Allow vmdk_create to work with protocol
vmdk: Check VMFS extent line field number
docs: updated qemu-img man page and qemu-doc to reflect VHDX support.
block: vhdx - improve error message, and .bdrv_check implementation
block/iscsi: Fix compilation for libiscsi 1.4.0 (API change)
qapi-schema: fix QEMU 1.8 references
dataplane: replace hostmem with memory_region_find
dataplane: change vring API to use VirtQueueElement
vring: factor common code for error exits
vring: create a common function to parse descriptors
sheepdog: fix dynamic grow for running qcow2 format
Anthony Liguori [Fri, 10 Jan 2014 19:04:48 +0000 (11:04 -0800)]
Merge remote-tracking branch 'mst/tags/for_anthony' into staging
acpi,pci,pc,fedora,virtio fixes and enhancements
This includes some Preparatory patches for cpu hotplug for q25 and memory
hotplug by Igor, tests and memory mapping change
by Laszlo and pci reset cleanup by Paolo.
There are also some fixes for fedora and virtio:
included here since they are test blockers for me.
Signed-off-by: Michael S. Tsirkin <[email protected]>
# gpg: Signature made Mon 23 Dec 2013 08:07:18 AM PST using RSA key ID D28D5469
# gpg: Can't check signature: public key not found
* mst/tags/for_anthony:
target-arm: fix build with gcc 4.8.2
virtio: add back call to virtio_bus_device_unplugged
piix: fix 32bit pci hole
qdev: switch reset to post-order
qdev: allow both pre- and post-order vists in qdev walking functions
pci: clean up resetting of IRQs
pci: do not export pci_bus_reset
ACPI/DSDT-CPU: cleanup bogus comment
ACPI: Q35 DSDT: fix CPU hotplug GPE0.2 handler
acpi: ich9: allow guest to clear SCI rised by GPE
acpi: factor out common pm_update_sci() into acpi core
acpi: piix4: remove not needed GPE0 mask
i440fx-test: verify firmware under 4G and 1M, both -bios and -pflash
i440fx-test: generate temporary firmware blob
i440fx-test: give each GTest case its own qtest
i440fx-test: qtest_start() should be paired with qtest_end()
hw/i386/pc_sysfw: support two flash drives
pc_piix: document gigabyte_align
piix: gigabyte alignment for ram
# gpg: Signature made Tue 24 Dec 2013 04:51:52 AM PST using RSA key ID 3E7E013F
# gpg: Good signature from "Andreas Färber <[email protected]>"
# gpg: aka "Andreas Färber <[email protected]>"
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg: There is no indication that the signature belongs to the owner.
# Primary key fingerprint: 174F 0347 1BCC 221A 6175 6F96 FA2E D12D 3E7E 013F
* afaerber/tags/qom-cpu-for-anthony:
target-i386: Cleanup 'foo=val' feature handling
target-i386: Cleanup 'foo' feature handling
target-i386: Convert 'check' and 'enforce' to static properties
target-i386: Convert 'hv_spinlocks' to static property
target-i386: Convert 'hv_vapic' to static property
target-i386: Convert 'hv_relaxed' to static property
cpu-exec: Optimize X86CPU usage in cpu_exec()
target-i386: Move apic_state field from CPUX86State to X86CPU
cputlb: Tidy memset() of arrays
cputlb: Use memset() when flushing entries
Anthony Liguori [Fri, 10 Jan 2014 18:48:46 +0000 (10:48 -0800)]
Merge remote-tracking branch 'pmaydell/tags/pull-target-arm-20140107' into staging
target-arm queue:
* further A64 decoder patches, including enabling the aarch64-linux-user
target; this includes full floating point support. Neon is not yet
supported.
* cadence UART model fixes.
* some minor bug fixes and cleanups.
* all the softfloat fixes required by the new A64 instructions;
several of these will also be used by PPC.
* pmaydell/tags/pull-target-arm-20140107: (61 commits)
target-arm: A64: Add support for FCVT between half, single and double
target-arm: A64: Add 1-source 32-to-32 and 64-to-64 FP instructions
target-arm: A64: Add floating-point<->integer conversion instructions
target-arm: A64: Add floating-point<->fixed-point instructions
target-arm: A64: Add extra VFP fixed point conversion helpers
target-arm: Ignore most exceptions from scalbn when doing fixpoint conversion
target-arm: Rename A32 VFP conversion helpers
target-arm: Prepare VFP_CONV_FIX helpers for A64 uses
softfloat: Add support for ties-away rounding
softfloat: Refactor code handling various rounding modes
softfloat: Add float16 <=> float64 conversion functions
softfloat: Factor out RoundAndPackFloat16 and NormalizeFloat16Subnormal
softfloat: Provide complete set of accessors for fp state
softfloat: Fix float64_to_uint32_round_to_zero
softfloat: Fix float64_to_uint32
softfloat: Fix float64_to_uint64_round_to_zero
softfloat: Add float32_to_uint64()
softfloat: Fix factor 2 error for scalbn on denormal inputs
softfloat: Only raise Invalid when conversions to int are out of range
softfloat: Fix float64_to_uint64
...
Anthony Liguori [Thu, 9 Jan 2014 19:24:48 +0000 (11:24 -0800)]
Merge remote-tracking branch 'afaerber/tags/qom-devices-for-anthony' into staging
QOM infrastructure fixes and device conversions
* QOM interface fixes and unit test
* Device no_user sanitization and documentation
* Device error reporting improvement
* Conversion of APIC, ICC, IOAPIC to QOM realization model
# gpg: Signature made Tue 24 Dec 2013 09:04:05 AM PST using RSA key ID 3E7E013F
# gpg: Good signature from "Andreas Färber <[email protected]>"
# gpg: aka "Andreas Färber <[email protected]>"
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg: There is no indication that the signature belongs to the owner.
# Primary key fingerprint: 174F 0347 1BCC 221A 6175 6F96 FA2E D12D 3E7E 013F
* afaerber/tags/qom-devices-for-anthony: (24 commits)
qdev-monitor: Improve error message for -device nonexistant
ioapic: QOM'ify ioapic
ioapic: Cleanup for QOM'ification
icc_bus: QOM'ify ICC
apic: QOM'ify APIC
apic: Cleanup for QOM'ification
qdev: Drop misleading qbus_free() function
qom: Detect bad reentrance during object_class_foreach()
tests: Test QOM interface casting
qom: Do not register interface "types" in the type table and fix names
qom: Split out object and class caches
qdev: Document that pointer properties kill device_add
hw: cannot_instantiate_with_device_add_yet due to pointer props
qdev-monitor: Avoid device_add crashing on non-device driver name
qdev: Do not let the user try to device_add when it cannot work
isa: Clean up use of cannot_instantiate_with_device_add_yet
vt82c686: Clean up use of cannot_instantiate_with_device_add_yet
piix3 piix4: Clean up use of cannot_instantiate_with_device_add_yet
ich9: Document why cannot_instantiate_with_device_add_yet
pci-host: Consistently set cannot_instantiate_with_device_add_yet
...
Anthony Liguori [Thu, 9 Jan 2014 19:24:12 +0000 (11:24 -0800)]
Merge remote-tracking branch 'mjt/trivial-patches' into staging
* mjt/trivial-patches:
acpi unit-test: Remove temporary disk after test
mainstone: Fix duplicate array values for key 'space'
pxa27x: Add 'const' attribute to keyboard maps
pxa27x: Reduce size of keyboard matrix mapping
doc: Mention chardev:id in available devices for -serial
configure: Python tests must be done before help message
configure: Rewrite code for help message
fix -boot strict regressed in commit 6ef4716
vl: make boot_strict variable static (not used outside vl.c)
x86: only allow real mode to access 32bit without LMA
linux-user: Use macro TARGET_NSIG_WORDS where possible
exynos4210: Use macro ARRAY_SIZE where possible
ui/cocoa: Use macro ARRAY_SIZE where possible
misc: Use macro ARRAY_SIZE where possible
openrisc: Fix spelling in comment (transaltion -> translation)
hw/arm/highbank: Simplify code (memory region in device state)
Anthony Liguori [Thu, 9 Jan 2014 19:23:49 +0000 (11:23 -0800)]
Merge remote-tracking branch 'pmaydell/tags/pull-target-arm-20140108' into staging
target-arm queue:
* further A64 decoder patches, including enabling the aarch64-linux-user
target; this includes full floating point support. Neon is not yet
supported.
* cadence UART model fixes.
* some minor bug fixes and cleanups.
* all the softfloat fixes required by the new A64 instructions;
several of these will also be used by PPC.
# gpg: Signature made Wed 08 Jan 2014 11:25:12 AM PST using RSA key ID 14360CDE
# gpg: Can't check signature: public key not found
* pmaydell/tags/pull-target-arm-20140108: (76 commits)
target-arm: A64: Add support for FCVT between half, single and double
target-arm: A64: Add 1-source 32-to-32 and 64-to-64 FP instructions
target-arm: A64: Add floating-point<->integer conversion instructions
target-arm: A64: Add floating-point<->fixed-point instructions
target-arm: A64: Add extra VFP fixed point conversion helpers
target-arm: Ignore most exceptions from scalbn when doing fixpoint conversion
target-arm: Rename A32 VFP conversion helpers
target-arm: Prepare VFP_CONV_FIX helpers for A64 uses
softfloat: Add support for ties-away rounding
softfloat: Refactor code handling various rounding modes
softfloat: Add float16 <=> float64 conversion functions
softfloat: Factor out RoundAndPackFloat16 and NormalizeFloat16Subnormal
softfloat: Provide complete set of accessors for fp state
softfloat: Fix float64_to_uint32_round_to_zero
softfloat: Fix float64_to_uint32
softfloat: Fix float64_to_uint64_round_to_zero
softfloat: Add float32_to_uint64()
softfloat: Fix factor 2 error for scalbn on denormal inputs
softfloat: Only raise Invalid when conversions to int are out of range
softfloat: Fix float64_to_uint64
...
Peter Maydell [Tue, 7 Jan 2014 17:19:14 +0000 (17:19 +0000)]
target-arm: A64: Add 1-source 32-to-32 and 64-to-64 FP instructions
This patch adds support for those instructions in the "Floating-point
data-processing (1 source)" group which are simple 32-bit-to-32-bit
or 64-bit-to-64-bit operations (ie everything except FCVT between
single/double/half precision).
We put the new round-to-int helpers in helper.c because they will
also be used by the new ARMv8 A32/T32 rounding instructions.
Signed-off-by: Alexander Graf <[email protected]>
[WN: Commit message tweak, merged single and double precision patches,
updated to new infrastructure.] Signed-off-by: Will Newton <[email protected]>
[PMM: reworked decode, split FCVT out into their own patch] Signed-off-by: Peter Maydell <[email protected]> Reviewed-by: Richard Henderson <[email protected]>
Add support for the AArch64 floating-point <-> integer conversion
instructions to disas_fpintconv. In the process we can rearrange
and simplify the detection of unallocated encodings a little.
We also correct a typo in the instruction encoding diagram for this
instruction group: bit 21 is 1, not 0.
This patch adds emulation for the instruction group labeled
"Floating-point <-> fixed-point conversions" in the ARM ARM.
Namely this includes the instructions SCVTF, UCVTF, FCVTZS, FCVTZU
(scalar, fixed-point).
Signed-off-by: Alexander Graf <[email protected]>
[WN: Commit message tweak, rebased, updated to new infrastructure.
Applied bug fixes from Michael Matz and Janne Grunau.] Signed-off-by: Will Newton <[email protected]>
[PMM: significant cleanup] Signed-off-by: Peter Maydell <[email protected]> Reviewed-by: Richard Henderson <[email protected]>
Peter Maydell [Tue, 7 Jan 2014 17:19:13 +0000 (17:19 +0000)]
target-arm: Ignore most exceptions from scalbn when doing fixpoint conversion
The VFP fixed point conversion helpers first call float_scalbn and
then convert the result to an integer. This scalbn operation may
set floating point exception flags for:
* overflow & inexact (if it overflows to infinity)
* input denormal squashed to zero
* output denormal squashed to zero
Of these, we only care about the input-denormal flag, since
the output of the whole scale-and-convert operation will be
an integer (so squashed-output-denormal and overflow don't
apply). Suppress the others by saving the pre-scalb exception
flags and only copying across a potential input-denormal flag.
Will Newton [Tue, 7 Jan 2014 17:19:13 +0000 (17:19 +0000)]
target-arm: Rename A32 VFP conversion helpers
The VFP conversion helpers for A32 round to zero as this is the only
rounding mode supported. Rename these helpers to make it clear that
they round to zero and are not suitable for use in the AArch64 code.
Will Newton [Tue, 7 Jan 2014 17:19:13 +0000 (17:19 +0000)]
target-arm: Prepare VFP_CONV_FIX helpers for A64 uses
Make the VFP_CONV_FIX helpers a little more flexible in
preparation for the A64 uses. This requires two changes:
* use the correct softfloat conversion function based on itype
rather than always the int32 one; this is possible now that
softfloat provides int16 versions and necessary for the
future conversion-to-int64 A64 variants. This also allows
us to drop the awkward 'sign' macro argument.
* split the 'fsz' argument which currently controls both
width of the input float type and width of the output
integer type into two; this will allow us to specify the
A64 64-bit-int-to-single conversion function, where the
two widths are different.
We can also drop the (itype##_t) cast now that softfloat
guarantees that all the itype##_to_float* functions take
an integer argument of exactly the correct type.
Peter Maydell [Tue, 7 Jan 2014 17:19:12 +0000 (17:19 +0000)]
softfloat: Add support for ties-away rounding
IEEE754-2008 specifies a new rounding mode:
"roundTiesToAway: the floating-point number nearest to the infinitely
precise result shall be delivered; if the two nearest floating-point
numbers bracketing an unrepresentable infinitely precise result are
equally near, the one with larger magnitude shall be delivered."
Implement this new mode (it is needed for ARM). The general principle
is that the required code is exactly like the ties-to-even code,
except that we do not need to do the "in case of exact tie clear LSB
to round-to-even", because the rounding operation naturally causes
the exact tie to round up in magnitude.
Peter Maydell [Tue, 7 Jan 2014 17:19:12 +0000 (17:19 +0000)]
softfloat: Refactor code handling various rounding modes
Refactor the code in various functions which calculates rounding
increments given the current rounding mode, so that instead of a
set of nested if statements we have a simple switch statement.
This will give us a clean place to add the case for the new
tiesAway rounding mode.
Peter Maydell [Tue, 7 Jan 2014 17:19:11 +0000 (17:19 +0000)]
softfloat: Factor out RoundAndPackFloat16 and NormalizeFloat16Subnormal
In preparation for adding conversions between float16 and float64,
factor out code currently done inline in the float16<=>float32
conversion functions into functions RoundAndPackFloat16 and
NormalizeFloat16Subnormal along the lines of the existing versions
for the other float types.
Note that we change the handling of zExp from the inline code
to match the API of the other RoundAndPackFloat functions; however
we leave the positioning of the binary point between bits 22 and 23
rather than shifting it up to the high end of the word.