The Floating-point Unavailable and Decrementer interrupts are being
registered at the same 0x900 address. The FPU should be at 0x800
instead.
Verified on MPC555, MPC860 and MPC885 user manuals.
Reported-by: BALATON Zoltan <balaton@eik.bme.hu>
Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20211208123029.2052625-2-farosas@linux.ibm.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
(Applies to 7441, 7445, 7450, 7451, 7455, 7457, 7447, 7447a and 7448)
The QEMU-side software TLB implementation for the 7450 family of CPUs
is being removed due to lack of known users in the real world. The
last users in the code were removed by the two previous commits.
A brief history:
The feature was added in QEMU by commit 7dbe11acd8 ("Handle all MMU
models in switches...") with the mention that Linux was not able to
handle the TLB miss interrupts and the MMU model would be kept
disabled.
At some point later, commit 8ca3f6c382 ("Allow selection of all
defined PowerPC 74xx (aka G4) CPUs.") enabled the model for the 7450
family without further justification.
We have since the year 2011 [1] been unable to run OpenBIOS in the
7450s and have not heard of any other software that is used with those
CPUs in QEMU. Attempts were made to find a guest OS that implemented
the TLB miss handlers and none were found among Linux 5.15, FreeBSD 13,
MacOS9, MacOSX and MorphOS 3.15.
All CPUs that registered this feature were moved to an MMU model that
replaces the software TLB with a QEMU hardware TLB
implementation. They can now run the same software as the 7400 CPUs,
including the OSes mentioned above.
References:
- https://bugs.launchpad.net/qemu/+bug/812398https://gitlab.com/qemu-project/qemu/-/issues/86
- https://lists.nongnu.org/archive/html/qemu-ppc/2021-11/msg00289.html
message id: 20211119134431.406753-1-farosas@linux.ibm.com
Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20211130230123.781844-4-farosas@linux.ibm.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
The e600 CPU is a successor of the 7448 and like all the 7450s CPUs,
it has an optional software TLB feature.
We have determined that there is no OS software support for the 7450
software TLB available these days. See the previous commit for more
information.
This patch disables the SPRs and instructions related to software TLB
from the e600 CPU.
No functional change intended. These facilities should be used by the
OS in interrupt handlers for interrupts that QEMU never generates.
Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20211130230123.781844-3-farosas@linux.ibm.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
(Applies to 7441, 7445, 7450, 7451, 7455, 7457, 7447 and 7447a)*
We have since 2011 [1] been unable to run OpenBIOS in the 7450s and
have not heard of any other software that is used with those CPUs in
QEMU. A current discussion [2] shows that the 7450 software TLB is
unsupported in Linux 5.15, FreeBSD 13, MacOS9, MacOSX and MorphOS
3.15. With no known support in firmware or OS, this means that no code
for any of the 7450 CPUs is ever ran in QEMU.
Since the implementation in QEMU of the 7400 MMU is the same as the
7450, except for the software TLB vs. hardware TLB search, this patch
changes all 7450 cpus to the 7400 MMU model. This has the practical
effect of disabling the software TLB feature while keeping other
aspects of address translation working as expected.
This allow us to run software on the 7450 family again.
*- note that the 7448 is currently aliased in QEMU for a 7400, so it
is unaffected by this change.
1- https://bugs.launchpad.net/qemu/+bug/812398https://gitlab.com/qemu-project/qemu/-/issues/86
2- https://lists.nongnu.org/archive/html/qemu-ppc/2021-11/msg00289.html
message id: 20211119134431.406753-1-farosas@linux.ibm.com
Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20211130230123.781844-2-farosas@linux.ibm.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
When computing the predicate "is this value currently formatted
for single precision", we do not want to round the value according
to the current rounding mode, nor perform a floating-point equality.
We want to see if the N bits that make up single-precision are the
only ones set within the register, and then a bitwise equality.
Fixes a bug in which a single-precision NaN is considered !SP,
because float64_eq(nan, nan) is always false.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-35-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
There is no double-rounding bug here, because the result is
merely an estimate to within 1 part in 256, but perform the
operation with float64r32_div for consistency.
Use float_flag_invalid_snan instead of recomputing the
snan-ness of the operand.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-34-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
There is no double-rounding bug here, because the result is
merely an estimate to within 1 part in 32, but perform the
operation with float64r32_div for consistency.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-33-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Use float64r32_mul. Fixes a double-rounding issue with performing
the compuation in float64 and then rounding afterward.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-32-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Use float64r32_{add,sub,div}. Fixes a double-rounding issue with
performing the compuation in float64 and then rounding afterward.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-31-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Use float64r32_sqrt. Fixes a double-rounding issue with performing
the compuation in float64 and then rounding afterward.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-30-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Use float64r32_muladd. Fixes a double-rounding issue with performing
the compuation in float64 and then rounding afterward.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-29-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
These variants take a float64 as input, compute the result to
infinite precision (as we do with FloatParts), round the result
to the precision and dynamic range of float32, and then return
the result in the format of float64.
This is the operation PowerPC requires for its float32 operations.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-28-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Use float_flag_invalid_snan instead of recomputing
the snan-ness of the operand.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-27-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Use float_flag_invalid_snan instead of recomputing
the snan-ness of the operand.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-26-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Now that vxsqrt and vxsnan are computed directly by softfloat,
we don't need to recompute it. Split out float_invalid_op_sqrt
to be used in several places. This fixes VSX_SQRT, which did
not order its tests correctly to eliminate NaN with sign set.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-25-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
We only needed one ieee arithmetic operation to raise
exceptions. To convert back to register form, we can
use our simpler non-arithmetic function.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-24-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Now that vxsnan is computed directly by softfloat,
we don't need to recompute it.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-23-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Calling helper_frsp directly from other helpers generates
the incorrect retaddr. Split out a helper that takes the
retaddr as a parameter.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-22-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
We will process flags other than in valid in helper_float_check_status,
which is invoked after the writeback to FRT.
Fixes a bug in which FRT is not written when OE/UE/XE are enabled.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-21-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Create a common function for all of the madd helpers.
Let the compiler tail call or inline as it chooses.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-20-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Now that vximz, vxisi, and vxsnan are computed directly by
softfloat, we don't need to recompute it. This replaces the
separate float{32,64}_maddsub_update_excp functions with a
single float_invalid_op_madd function.
Fix VSX_MADD by passing sfprf to float_invalid_op_madd,
whereas the previous *_maddsub_update_excp assumed it true.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-19-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Let float64_round_to_int detect and silence snans.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-18-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
In GEN_FLOAT_B, we called helper_reset_fpstatus immediately
before calling helper_fri*. Therefore get_float_exception_flags
is known to be zero, and this code can be simplified.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-17-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
This is the proper type for the enumeration.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20211119160502.17432-16-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
There's no reason the callers can't tail call to one function.
Leave it up to the compiler either way.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20211119160502.17432-15-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
We were returning nanval for any instance of invalid being set,
but that is an incorrect for VXCVI. This failure can be seen
in the float_convs tests.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-14-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Now that vxsnan is computed directly by softfloat,
we don't need to recompute it via classes.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-13-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Fixes a bug in which e.g XE enabled causes inexact to be raised
before the writeback to the architectural register.
All of the users of GEN_FLOAT_B either set set_fprf, or are one
of the convert-to-integer instructions that require this behaviour.
Split out the two gen_helper_* calls in gen_compute_fprf_float64
and protect only the first with set_fprf.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-12-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Now that vxidi, vxzdz, and vxsnan are computed directly by
softfloat, we don't need to recompute it via classes.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-11-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Now that vximz and vxsnan are computed directly by
softfloat, we don't need to recompute it via classes.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-10-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Now that vxisi and vxsnan are computed directly by
softfloat, we don't need to recompute it via classes.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-9-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
PowerPC has this flag, and it's easier to compute it here
than after the fact.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-8-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
PowerPC has this flag, and it's easier to compute it here
than after the fact.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-7-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
PowerPC has this flag, and it's easier to compute it here
than after the fact.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-6-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
PowerPC has these flags, and it's easier to compute them here
than after the fact.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-5-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
PowerPC has this flag, and it's easier to compute it here
than after the fact.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-4-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
PowerPC has this flag, and it's easier to compute it here
than after the fact.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-3-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
We will shortly have more than 8 bits of exceptions.
Repack the existing flags into low bits and reformat to hex.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20211119160502.17432-2-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Leonardo Garcia <lagarcia@br.ibm.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
[ clg: - replaced lingua by terminology
- add a new line at EOF ]
Message-Id: <e20319dcf0ec37bedd915c740c3813eb0e58ead4.1638982486.git.lagarcia@br.ibm.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
The purpose of this document is to substitute the content currently
available in the QEMU wiki at [0]. This initial version does contain
some additional content as well. Whenever this documentation gets
upstream and is reflected in [1], the QEMU wiki will be edited to point
to this documentation, so that we only need to keep it updated in one
place.
0. https://wiki.qemu.org/Documentation/Platforms/POWER
1. https://qemu.readthedocs.io/en/latest/system/ppc/pseries.html
Signed-off-by: Leonardo Garcia <lagarcia@br.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Message-Id: <66b6fdde52062fdf4f4b4dc35a9f06a899c88293.1638981899.git.lagarcia@br.ibm.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Setting -uuid in the pnv machine does not work:
./qemu-system-ppc64 -machine powernv8,accel=tcg -uuid 7ff61ca1-a4a0-4bc1-944c-abd114a35e80
qemu-system-ppc64: error creating device tree: (fdt_property_string(fdt, "system-id", buf)): FDT_ERR_BADSTATE
This happens because we're using fdt_property_string(), which is a
sequential write function that is supposed to be used when we're
building a new FDT, in a case where read/writing into an existing FDT.
Fix it by using fdt_setprop_string() instead.
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20211207094858.744386-1-danielhb413@gmail.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Put in a more accessible place the reasoning behind our decision
to officially drop KVM support in the powernv machine.
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20211130133153.444601-3-danielhb413@gmail.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
If one tries to use -machine powernv9,accel=kvm in a Power9 host, a
cryptic error will be shown:
qemu-system-ppc64: Register sync failed... If you're using kvm-hv.ko, only "-cpu host" is possible
qemu-system-ppc64: kvm_init_vcpu: kvm_arch_init_vcpu failed (0): Invalid argument
Appending '-cpu host' will throw another error:
qemu-system-ppc64: invalid chip model 'host' for powernv9 machine
The root cause is that in IBM PowerPC we have different specs for the bare-metal
and the guests. The bare-metal follows OPAL, the guests follow PAPR. The kernel
KVM modules presented in the ppc kernels implements PAPR. This means that we
can't use KVM accel when using the powernv machine, which is the emulation of
the bare-metal host.
All that said, let's give a more informative error in this case.
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Message-Id: <20211130133153.444601-2-danielhb413@gmail.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
The PCIe extended configuration space on the device is not currently
accessible to the host. if by default, it is still inaccessible for
conventional for PCIe buses, add the current flag
PCI_BUS_EXTENDED_CONFIG_SPACE on the root bus permits PCI-E extended
config space access.
Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.ibm.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20211109145053.43524-1-clombard@linux.vnet.ibm.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
This test, if enabled by hand, was failing when the ivhsmem device was
being declared as DEVICE_NATIVE_ENDIAN with the following error:
/ppc64/ivshmem/pair: OK
/ppc64/ivshmem/server:
**
ERROR:/home/danielhb/qemu/tests/qtest/ivshmem-test.c:367:test_ivshmem_server:
assertion failed (ret != 0): (0 != 0)
Aborted
After the endianness change done in the previous patch, we can verify in
both a a Power 9 little-endian host and in a Power 8 big-endian host
that this test is now passing:
$ QTEST_QEMU_BINARY=./ppc64-softmmu/qemu-system-ppc64 ./tests/qtest/ivshmem-test -m slow
/ppc64/ivshmem/single: OK
/ppc64/ivshmem/hotplug: OK
/ppc64/ivshmem/memdev: OK
/ppc64/ivshmem/pair: OK
/ppc64/ivshmem/server: OK
Let's keep it that way by officially enabling it for ppc64.
Acked-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20211124092948.335389-3-danielhb413@gmail.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
The ivshmem device, as with most PCI devices, uses little endian byte
order. However, the endianness of its mmio_ops is marked as
DEVICE_NATIVE_ENDIAN. This presents not only the usual problems with big
endian hosts but also with PowerPC little endian hosts as well, since
the Power architecture in QEMU uses big endian hardware (XIVE controller,
PCI Host Bridges, etc) even if the host is in little endian byte order.
As it is today, the IVPosition of the device will be byte swapped when
running in Power BE and LE. This can be seen by changing the existing
qtest 'ivshmem-test' to run in ppc64 hosts and printing the IVPOSITION
regs in test_ivshmem_server() right after the VM ids assert. For x86_64
the VM id values read are '0' and '1', for ppc64 (tested in a Power8
RHEL 7.9 BE server) and ppc64le (tested in a Power9 RHEL 8.6 LE server)
the ids will be '0' and '0x1000000'.
Change this device to LITTLE_ENDIAN fixes the issue for Power hosts of
both endianness, and every other big-endian architecture that might use
this device, without impacting x86 users.
Fixes: cb06608e17 ("ivshmem: convert to memory API")
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/168
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20211124092948.335389-2-danielhb413@gmail.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Fabiano Rosas
Richard Henderson
Leonardo Garcia
Daniel Henrique Barboza
Christophe Lombard
Matheus Ferst