ISA v2.06 adds new variations of wait, specified by the WC field. These
are not all compatible with the prior wait implementation, because they
add additional conditions that cause the processor to resume, which can
cause software to hang or run very slowly.
At this moment, with the current wait implementation and a pseries guest
using mainline kernel with new wait upcodes [1], QEMU hangs during boot if
more than one CPU is present:
qemu-system-ppc64 -M pseries,x-vof=on -cpu POWER10 -smp 2 -nographic
-kernel zImage.pseries -no-reboot
QEMU will exit (as there's no filesystem) if the test "passes", or hang
during boot if it hits the bug.
ISA v3.0 changed the wait opcode and removed the new variants (retaining
the WC field but making non-zero values reserved).
ISA v3.1 added new WC values to the new wait opcode, and added a PL
field.
This patch implements the new wait encoding and supports WC variants
with no-op implementations, which provides basic correctness as
explained in comments.
[1] https://lore.kernel.org/all/20220720132132.903462-1-npiggin@gmail.com/
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Víctor Colombo <victor.colombo@eldorado.org.br>
Tested-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20220720133352.904263-1-npiggin@gmail.com>
[danielhb: added information about the bug being fixed]
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
According to PowerISA 3.1B, Book III 6.7.6 programming note, the
page directory base addresses are expected to be aligned to their
size. Real hardware seems to rely on that and will access the
wrong address if they are misaligned. This results in a
translation failure even if the page tables seem to be properly
populated.
Signed-off-by: Leandro Lupori <leandro.lupori@eldorado.org.br>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20220628133959.15131-4-leandro.lupori@eldorado.org.br>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
This initial version supports the invalidation of one or all
TLB entries. Flush by PID/LPID, or based in process/partition
scope is not supported, because it would make using the
generic QEMU TLB implementation hard. In these cases, all
entries are flushed.
Signed-off-by: Leandro Lupori <leandro.lupori@eldorado.org.br>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20220712193741.59134-3-leandro.lupori@eldorado.org.br>
[danielhb: moved 'set' declaration to TLBIE_RIC_PWC block]
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
The 'error' argument of gen_inval_exception will be or-ed with
POWERPC_EXCP_INVAL, so it should always be a constant prefixed with
POWERPC_EXCP_INVAL_. No functional change is intended,
spr_write_excp_vector is only used by register_BookE_sprs, and
powerpc_excp_booke ignores the lower 4 bits of the error code on
POWERPC_EXCP_INVAL exceptions.
Also, take the opportunity to replace printf with qemu_log_mask.
Signed-off-by: Matheus Ferst <matheus.ferst@eldorado.org.br>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20220627141104.669152-7-matheus.ferst@eldorado.org.br>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
A call to "gen_(hv)priv_exception" should use POWERPC_EXCP_PRIV_* as the
'error' argument instead of POWERPC_EXCP_INVAL_*, and POWERPC_EXCP_FU is
an exception type, not an exception error code. To correctly set
FSCR[IC], we should raise Facility Unavailable with this exception type
and IC value as the error code.
Fixes: 565cb10967 ("target/ppc: add user read/write functions for MMCR0")
Signed-off-by: Matheus Ferst <matheus.ferst@eldorado.org.br>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20220627141104.669152-6-matheus.ferst@eldorado.org.br>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
POWERPC_EXCP_INVAL should only be or-ed with other constants prefixed
with POWERPC_EXCP_INVAL_. Also, take the opportunity to move both
helpers under #if !defined(CONFIG_USER_ONLY) as the instructions that
use them are privileged.
No functional change is intended, the lower 4 bits of the error code are
ignored by all powerpc_excp_* methods on POWERPC_EXCP_INVAL exceptions.
Reported-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Matheus Ferst <matheus.ferst@eldorado.org.br>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20220627141104.669152-5-matheus.ferst@eldorado.org.br>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Testing on a POWER9 DD2.3, we observed that the Linux kernel delivers a
signal with si_code ILL_PRVOPC (5) when a userspace application tries to
use slbfee. To obtain this behavior on linux-user, we should use
POWERPC_EXCP_PRIV with POWERPC_EXCP_PRIV_OPC.
No functional change is intended for softmmu targets as
gen_hvpriv_exception uses the same 'exception' argument
(POWERPC_EXCP_HV_EMU) for raise_exception_*, and the powerpc_excp_*
methods do not use lower bits of the exception error code when handling
POWERPC_EXCP_{INVAL,PRIV}.
Reported-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Matheus Ferst <matheus.ferst@eldorado.org.br>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20220627141104.669152-3-matheus.ferst@eldorado.org.br>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Commit 80d11f4467 ("Add definitions for Freescale PowerPC implementations")
changed core type of MPC8555 and MPC8560 from e500v1 to e500v2.
But both MPC8555 and MPC8560 have just e500v1 cores, there are no features
of e500v2 cores. It can be verified by reading NXP documentations:
https://www.nxp.com/docs/en/data-sheet/MPC8555EEC.pdfhttps://www.nxp.com/docs/en/data-sheet/MPC8560EC.pdfhttps://www.nxp.com/docs/en/reference-manual/MPC8555ERM.pdfhttps://www.nxp.com/docs/en/reference-manual/MPC8560RM.pdf
Therefore fix core type of MPC8555 and MPC8560 back to e500v1.
Just for completeness, here is list of all Motorola/Freescale/NXP
processors which were released and have e500v1 or e500v2 cores:
e500v1: MPC8540 MPC8541 MPC8555 MPC8560
e500v2: BSC9131 BSC9132
C291 C292 C293
MPC8533 MPC8535 MPC8536 MPC8543 MPC8544 MPC8545 MPC8547
MPC8548 MPC8567 MPC8568 MPC8569 MPC8572
P1010 P1011 P1012 P1013 P1014 P1015 P1016 P1020 P1021
P1022 P1024 P1025 P2010 P2020
Sorted alphabetically; not by release date / generation / feature set.
All this is from public information available on NXP website.
Seems that qemu has support only for some subset of MPC85xx processors.
Historically processors with e500 cores have mpc85xx family codename and
lot of software have them in mpc85xx architecture subdirectory.
Note that GCC uses -mcpu=8540 option for specifying e500v1 core and
-mcpu=8548 option for specifying e500v2 core.
So sometimes (mpc)8540 is alias for e500v1 and (mpc)8548 is alias for
e500v2.
Fixes: 80d11f4467 ("Add definitions for Freescale PowerPC implementations")
Signed-off-by: Pali Rohár <pali@kernel.org>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20220703195029.23793-1-pali@kernel.org>
[danielhb: added more context in the commit msg]
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
QEMU emulates a *lot* of PowerPC-based machines - having a CPU
that is named "default" and cannot be used with most of those
machines sounds just wrong. Thus let's remove this old and confusing
alias now.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20220705151030.662140-1-thuth@redhat.com>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Implements the Convert Binary Coded Decimal To Declets instruction.
Since libdecnumber doesn't expose the methods for direct conversion
(decDigitsToDPD, BCD2DPD, etc.), the BCD values are converted to
decimal32 format, from which the declets are extracted.
Where the behavior is undefined, we try to match the result observed in
a POWER9 DD2.3.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Matheus Ferst <matheus.ferst@eldorado.org.br>
Signed-off-by: Víctor Colombo <victor.colombo@eldorado.org.br>
Message-Id: <20220629162904.105060-11-victor.colombo@eldorado.org.br>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
It keeps repeating, move it to the header. This uses __builtin_ffsll() to
allow using the macros in #define.
This is not using the QEMU's FIELD macros as this would require changing
all such macros found in skiboot (the PPC PowerNV firmware).
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20220628080544.1509428-1-aik@ozlabs.ru>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
FPSCR_* bit values in QEMU are in the 'inverted' order from what Power
ISA defines (e.g. FPSCR.FI is bit 46 but is defined as 17 in cpu.h).
Now that PPC_BIT_NR macro was introduced to fix this situation for the
MSR bits, we can use it for the FPSCR bits too.
Also, adjust the comments to make then fit in 80 columns
Signed-off-by: Víctor Colombo <victor.colombo@eldorado.org.br>
Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com>
Message-Id: <20220622193203.127698-1-victor.colombo@eldorado.org.br>
[danielhb: fixed 'exceptio' typo in target/ppc/cpu.h]
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
The 'resume_as_sreset' attribute of a cpu is set when a thread is
entering a stop state on ppc books. It causes the thread to be
re-routed to vector 0x100 when woken up by an exception. So it must be
cleared on reset or a thread might be re-routed unexpectedly after a
reset, when it was not in a stop state and/or when the appropriate
exception handler isn't set up yet.
Using skiboot, it can be tested by resetting the system when it is
quiet and most threads are idle and in stop state.
After the reset occurs, skiboot elects a primary thread and all the
others wait in secondary_wait. The primary thread does all the system
initialization from main_cpu_entry() and at some point, the
decrementer interrupt starts ticking. The exception vector for the
decrementer interrupt is in place, so that shouldn't be a
problem. However, if that primary thread was in stop state prior to
the reset, and because the resume_as_sreset parameters is still set,
it is re-routed to exception vector 0x100. Which, at that time, is
still defined as the entry point for BML. So that primary thread
restarts as new and ends up being treated like any other secondary
thread. All threads are now waiting in secondary_wait.
It results in a full system hang with no message on the console, as
the uart hasn't been init'ed yet. It's actually not obvious to realise
what's happening if not tracing reset (-d cpu_reset). The fix is
simply to clear the 'resume_as_sreset' attribute on reset.
Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20220617095222.612212-1-fbarrat@linux.ibm.com>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>