As per OpenRISC spec 1.4 FPCSR can be read and written in user mode.
Update mtspr and mfspr helpers to support this by moving the is_user
check into the helper.
Link: https://raw.githubusercontent.com/openrisc/doc/master/openrisc-arch-1.4-rev0.pdf
Signed-off-by: Stafford Horne <shorne@gmail.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
The value passed is always true, and if the target's
synchronize_from_tb hook is non-trivial, not exiting
may be erroneous.
Reviewed-by: Claudio Fontana <cfontana@suse.de>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Since we do not plan to exit, use cpu_unwind_state_data
and extract exactly the data requested.
This is a bug fix, in that we no longer clobber dflag.
Consider:
l.j L2 // branch
l.mfspr r1, ppc // delay
L1: boom
L2: l.lwa r3, (r4)
Here, dflag would be set by cpu_restore_state (because that is the current
state of the cpu), but but not cleared by tb_stop on exiting the TB
(because DisasContext has recorded the current value as zero).
The next TB begins at L2 with dflag incorrectly set. If the load has a
tlb miss, then the exception will be delivered as per a delay slot:
with DSX set in the status register and PC decremented (delay slots
restart by re-executing the branch). This will cause the return from
interrupt to go to L1, and boom!
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
We have called cpu_restore_state asserting will_exit.
Do not go back on that promise. This affects icount.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
When running SMP systems we sometimes were seeing lockups where
IPI interrupts were being raised by never handled.
This looks to be caused by 2 issues in the openrisc interrupt handling
logic.
1. After clearing an interrupt the openrisc_cpu_set_irq handler will
always clear PICSR. This is not correct as masked interrupts
should still be visible in PICSR.
2. After setting PICMR (mask register) and exposed interrupts should
cause an interrupt to be raised. This was not being done so add it.
This patch fixes both issues.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Stafford Horne <shorne@gmail.com>
This patch enables multithread TCG for OpenRISC. Since the or1k shared
syncrhonized timer can be updated from each vCPU via helpers we use a
mutex to synchronize updates.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Stafford Horne <shorne@gmail.com>
Stop including sysemu/sysemu.h in files that don't need it.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20210416171314.2074665-2-thuth@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
In the mtspr helper we attempt to check for "is the timer disabled"
with "if (env->ttmr & TIMER_NONE)". This is wrong because TIMER_NONE
is zero and the condition is always false (Coverity complains about
the dead code.)
The correct check would be to test whether the TTMR_M field in the
register is equal to TIMER_NONE instead. However, the
cpu_openrisc_timer_update() function checks whether the timer is
enabled (it looks at cpu->env.is_counting, which is set to 0 via
cpu_openrisc_count_stop() when the TTMR_M field is set to
TIMER_NONE), so there's no need to check for "timer disabled" in the
target/openrisc code. Instead, simply remove the dead code.
Fixes: Coverity CID 1005812
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Stafford Horne <shorne@gmail.com>
Message-id: 20201103114654.18540-1-peter.maydell@linaro.org
These registers are read-only and implementation specific.
Initiailize VR for the first time; take the OR1200 values
from the verilog source.
Note that moving fields within CPUOpenRISCState does not
affect migration.
Reviewed-by: Stafford Horne <shorne@gmail.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
These SPRs are read-only. The writes can simply be ignored,
as we already do for other read-only (or missing) registers.
There is no reason to mask the value in env->vr.
Reviewed-by: Stafford Horne <shorne@gmail.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Basically, the context could get the MachineState reference via call
chains or unrecommended qdev_get_machine() in !CONFIG_USER_ONLY mode.
A local variable of the same name would be introduced in the declaration
phase out of less effort OR replace it on the spot if it's only used
once in the context. No semantic changes.
Signed-off-by: Like Xu <like.xu@linux.intel.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20190518205428.90532-4-like.xu@linux.intel.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Cleanup in the boilerplate that each target must define.
Replace openrisc_env_get_cpu with env_archcpu. The combination
CPU(openrisc_env_get_cpu) should have used ENV_GET_CPU to begin;
use env_cpu now.
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
It's either "GNU *Library* General Public version 2" or "GNU Lesser
General Public version *2.1*", but there was no "version 2.0" of the
"Lesser" library. So assume that version 2.1 is meant here.
Cc: Stafford Horne <shorne@gmail.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Acked-by: Stafford Horne <shorne@gmail.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <1548252536-6242-3-git-send-email-thuth@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
The interrupt controller mask register (PICMR) allows writing any value
to any of the 32 interrupt mask bits. Writing a 0 masks the interrupt
writing a 1 unmasks (enables) the the interrupt.
For some reason the old code was or'ing the write values to the PICMR
meaning it was not possible to ever mask a interrupt once it was
enabled.
I have tested this by running linux 4.18 and my regular checks, I don't
see any issues.
Reported-by: Davidson Francis <davidsondfgl@gmail.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Stafford Horne <shorne@gmail.com>
The sizes are already the same, however, we can improve things
if they are identical by design.
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Stafford Horne <shorne@gmail.com>
The code in cpu_mmu_index does not properly honor SR_DME.
This bug has workarounds elsewhere in that we flush the
tlb more often than necessary, on the state changes that
should be reflected in a change of mmu_index.
Fixing this means that we can respect the mmu_index that
is given to tlb_flush.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Stafford Horne <shorne@gmail.com>
The previous code was confused, avoiding the flush of the old entry
if the new entry is invalid. We need to flush the old page if the
old entry is valid and the new page if the new entry is valid.
This bug was masked by over-flushing elsewhere.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Stafford Horne <shorne@gmail.com>
While we had defines for *_WAYS, we didn't define more than 1.
Reduce the complexity by eliminating this unused dimension.
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Stafford Horne <shorne@gmail.com>
There is no reason to use an indirect branch instead
of simply testing the SR bits that control mmu state.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Stafford Horne <shorne@gmail.com>
There is no reason to allocate this separately. This was probably
copied from target/mips which makes the same mistake.
While doing so, move tlb into the clear-on-reset range. While not
all of the TLB bits are guaranteed zero on reset, all of the valid
bits are cleared, and the rest of the bits are unspecified.
Therefore clearing the whole of the TLB is correct.
Reviewed-by: Stafford Horne <shorne@gmail.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Stafford Horne <shorne@gmail.com>
Rather than pass base+offset to the helper, pass the full index.
In most cases the base is r0 and optimization yields a constant.
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Stafford Horne <shorne@gmail.com>
Missing break when this feature was added in 89e71e873d
("target/openrisc: implement shadow registers"). This was causing
strange issues as we get writes into the translation block jump cache
and other bits of state.
Fixes: 89e71e873d ("target/openrisc: implement shadow registers")
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Stafford Horne <shorne@gmail.com>
In icount mode, instructions that access io memory spaces in the middle
of the translation block invoke TB recompilation. After recompilation,
such instructions become last in the TB and are allowed to access io
memory spaces.
When the code includes instruction like i386 'xchg eax, 0xffffd080'
which accesses APIC, QEMU goes into an infinite loop of the recompilation.
This instruction includes two memory accesses - one read and one write.
After the first access, APIC calls cpu_report_tpr_access, which restores
the CPU state to get the current eip. But cpu_restore_state_from_tb
resets the cpu->can_do_io flag which makes the second memory access invalid.
Therefore the second memory access causes a recompilation of the block.
Then these operations repeat again and again.
This patch moves resetting cpu->can_do_io flag from
cpu_restore_state_from_tb to cpu_loop_exit* functions.
It also adds a parameter for cpu_restore_state which controls restoring
icount. There is no need to restore icount when we only query CPU state
without breaking the TB. Restoring it in such cases leads to the
incorrect flow of the virtual time.
In most cases new parameter is true (icount should be recalculated).
But there are two cases in i386 and openrisc when the CPU state is only
queried without the need to break the TB. This patch fixes both of
these cases.
Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru>
Message-Id: <20180409091320.12504.35329.stgit@pasha-VirtualBox>
[rth: Make can_do_io setting unconditional; move from cpu_exec;
make cpu_loop_exit_{noexc,restore} call cpu_loop_exit.]
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
In order to support multicore system we move some of the previously
static state variables into the state of each core.
On the other hand in order to allow timers to be synced between each
code the ttcr (tick timer count register) is moved out of the core.
This is not as per real hardware spec which has a separate timer counter
per core, but it seems the most simple way to keep each clock in sync.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Stafford Horne <shorne@gmail.com>
Previously coreid and numcores were hard coded as 0 and 1 respectively
as OpenRISC QEMU did not have multicore support.
Multicore support is now being added so these registers need to have
configured values.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Stafford Horne <shorne@gmail.com>
The OpenRISC architecture has the Power Management Register (PMR)
special purpose register to manage cpu power states. The interesting
modes are:
* Doze Mode (DME) - Stop cpu except timer & pic - wake on interrupt
* Sleep Mode (SME) - Stop cpu and all units - wake on interrupt
* Suspend Model (SUME) - Stop cpu and all units - wake on reset
The linux kernel will set DME when idle.
This patch implements the PMR SPR and halts the qemu cpu when there is a
change to DME or SME. This means that openrisc qemu in no longer peggs
a host cpu at 100%.
In order for this to work we need to kick the CPU when timers are
expired. Update the cpu timer to kick the cpu upon each timer event.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Stafford Horne <shorne@gmail.com>
Shadow registers are part of the openrisc spec along with sr[cid], as
part of the fast context switching feature. When exceptions occur,
instead of having to save registers to the stack if enabled the CID will
increment and a new set of registers will be available.
This patch only implements shadow registers which can be used as extra
scratch registers via the mfspr and mtspr if required. This is
implemented in a way where it would be easy to add on the fast context
switching, currently cid is hardcoded to 0.
This is need for openrisc linux smp kernels to boot correctly.
Signed-off-by: Stafford Horne <shorne@gmail.com>
These are used to identify the processor in SMP system. Their
definition has been defined in verilog cores but it not yet part of the
spec but it will be soon.
The proposal for this is available:
https://openrisc.io/proposals/core-identifier-and-number-of-cores
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Stafford Horne <shorne@gmail.com>
Exception Vector Base Address Register (EVBAR) - This optional register
can be used to apply an offset to the exception vector addresses.
The significant bits (31-12) of the vector offset address for each
exception depend on the setting of the Supervision Register (SR)'s EPH
bit and the Exception Vector Base Address Register (EVBAR).
Its presence is indicated by the EVBARP bit in the CPU Configuration
Register (CPUCFGR).
Signed-off-by: Tim 'mithro' Ansell <mithro@mithis.com>
Signed-off-by: Stafford Horne <shorne@gmail.com>
The NPC SPR is really only supposed to be used for FPGA debugging.
It contains the same contents as PC, unless one plays games. Follow
the or1ksim implementation in flushing delayed branch state when it
is changed.
The PPC SPR need not be updated every instruction, merely when we
exit the TB or attempt to read its contents.
Signed-off-by: Richard Henderson <rth@twiddle.net>
Significantly simplifies the implementation of the use of MAC.
Reviewed-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de>
Signed-off-by: Richard Henderson <rth@twiddle.net>
This avoids having to keep merging and extracting the flag from SR.
Reviewed-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de>
Signed-off-by: Richard Henderson <rth@twiddle.net>
We have never has the concept of global TLB entries which would avoid
the flush so we never actually use this flag. Drop it and make clear
that tlb_flush is the sledge-hammer it has always been.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
[DG: ppc portions]
Acked-by: David Gibson <david@gibson.dropbear.id.au>
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.
Acked-by: Laurent Vivier <laurent@vivier.eu> [m68k part]
Acked-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> [tricore part]
Acked-by: Michael Walle <michael@walle.cc> [lm32 part]
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> [s390x part]
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> [s390x part]
Acked-by: Eduardo Habkost <ehabkost@redhat.com> [i386 part]
Acked-by: Artyom Tarasenko <atar4qemu@gmail.com> [sparc part]
Acked-by: Richard Henderson <rth@twiddle.net> [alpha part]
Acked-by: Max Filippov <jcmvbkbc@gmail.com> [xtensa part]
Reviewed-by: David Gibson <david@gibson.dropbear.id.au> [ppc part]
Acked-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com> [crisµblaze part]
Acked-by: Guan Xuetao <gxt@mprc.pku.edu.cn> [unicore32 part]
Signed-off-by: Thomas Huth <thuth@redhat.com>
