bdrv_getlength could fail, check the return value before using it.
Return NULL and set errno if it fails. Callers are updated to handle
the error case.
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Insanely large requests could cause an integer overflow in
bdrv_rw_co() while converting sectors to bytes. This patch catches the
problem and returns an error (if we hadn't overflown the integer here,
bdrv_check_byte_request() would have rejected the request, so we're not
breaking anything that was supposed to work before).
We actually do have a test case that triggers behaviour where we
accidentally let such a request pass, so that it would return success,
but read 0 bytes instead of the requested 4 GB. It fails now like it
should.
If the vdi block driver wants to be able to deal with huge images, it
can't read the whole block bitmap at once into memory like it does
today, but needs to use a metadata cache like qcow2 does.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Commit 8f4754ed intended to protect against integer overflow bugs in
block drivers by making sure that a single request that is passed to
drivers is no longer than INT_MAX bytes.
However, meanwhile there are some callers that don't use that code path
any more but call bdrv_check_byte_request() directy, so let's add a
check there as well.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
* AArch64 system mode support; this is all the CPU emulation code
but not the virt board support
* cadence_ttc match register bugfix
* Allwinner A10 PIC, PIT and ethernet fixes
[with update to avoid duplicate typedef]
* zynq-slcr rewrite
* cadence_gem bugfix
* fix for SMLALD/SMLSLD insn in A32
* fix for SQXTUN in A64
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Merge remote-tracking branch 'remotes/pmaydell/tags/pull-target-arm-20140417-1' into staging
target-arm queue:
* AArch64 system mode support; this is all the CPU emulation code
but not the virt board support
* cadence_ttc match register bugfix
* Allwinner A10 PIC, PIT and ethernet fixes
[with update to avoid duplicate typedef]
* zynq-slcr rewrite
* cadence_gem bugfix
* fix for SMLALD/SMLSLD insn in A32
* fix for SQXTUN in A64
# gpg: Signature made Thu 17 Apr 2014 21:35:57 BST using RSA key ID 14360CDE
# gpg: Good signature from "Peter Maydell <peter.maydell@linaro.org>"
* remotes/pmaydell/tags/pull-target-arm-20140417-1: (51 commits)
target-arm: A64: fix unallocated test of scalar SQXTUN
arm: translate.c: Fix smlald Instruction
net: cadence_gem: Make phy respond to broadcast
misc: zynq_slcr: Make DB_PRINTs always compile
misc: zynq_slcr: Convert SBD::init to object init
misc: zynq-slcr: Rewrite
allwinner-emac: update irq status after writes to interrupt registers
allwinner-emac: set autonegotiation complete bit on link up
allwinner-a10-pit: implement prescaler and source selection
allwinner-a10-pit: use level triggered interrupts
allwinner-a10-pit: avoid generation of spurious interrupts
allwinner-a10-pic: fix behaviour of pending register
allwinner-a10-pic: set vector address when an interrupt is pending
timer: cadence_ttc: Fix match register write logic
target-arm/gdbstub64.c: remove useless 'break' statement.
target-arm: Dump 32-bit CPU state if 64 bit CPU is in AArch32
target-arm: Handle the CPU being in AArch32 mode in the AArch64 set_pc
target-arm: Make Cortex-A15 CBAR read-only
target-arm: Implement CBAR for Cortex-A57
target-arm: Implement Cortex-A57 implementation-defined system registers
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The test for the U bit was incorrectly inverted in the scalar case of SQXTUN.
This doesn't affect the vector case as the U bit is used to select XTN(2).
Reported-by: Hao Liu <hao.liu@arm.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Claudio Fontana <claudio.fontana@huawei.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Cc: qemu-stable@nongnu.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The smlald (and probably smlsld) instruction was doing incorrect sign
extensions of the operands amongst 64bit result calculation. The
instruction psuedo-code is:
operand2 = if m_swap then ROR(R[m],16) else R[m];
product1 = SInt(R[n]<15:0>) * SInt(operand2<15:0>);
product2 = SInt(R[n]<31:16>) * SInt(operand2<31:16>);
result = product1 + product2 + SInt(R[dHi]:R[dLo]);
R[dHi] = result<63:32>;
R[dLo] = result<31:0>;
The result calculation should be done in 64 bit arithmetic, and hence
product1 and product2 should be sign extended to 64b before calculation.
The current implementation was adding product1 and product2 together
then sign-extending the intermediate result leading to false negatives.
E.G. if product1 = product2 = 0x4000000, their sum = 0x80000000, which
will be incorrectly interpreted as -ve on sign extension.
We fix by doing the 64b extensions on both product1 and product2 before
any addition/subtraction happens.
We also fix where we were possibly incorrectly setting the Q saturation
flag for SMLSLD, which the ARM ARM specifically says is not set.
Reported-by: Christina Smith <christina.smith@xilinx.com>
Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 2cddb6f5a15be4ab8d2160f3499d128ae93d304d.1397704570.git.peter.crosthwaite@xilinx.com
Cc: qemu-stable@nongnu.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Change the DB_PRINT macro over to a regular if() rather than
conditional compilation to give constant compile testing of formats.
Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Message-id: 942477847353c5cff5f45a228cc88c633dc012f3.1396503037.git.peter.crosthwaite@xilinx.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Near total rewrite of this device model. It is stylistically
obsolete, has numerous coverity fails and is not up to date with latest
Xilinx documentation. Fix.
The registers are flattened into a single array. This greatly simplifies
the MMIO accessor functions.
We take the oppurtunity to update the register Macro definitions to
match the latest TRM. Xilinx has de-documented some regs hence there are
some straight deletions. We only do this however in the case or a stock
read-as-written reset-zero register. Non-zero resets are always
preserved. New register definitions are added as needed.
This all comes with a VMSD version break as the union layout from before
was a bit strange and we are better off without it.
Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Message-id: 3aa016167b352ed224666909217137285fd3351d.1396503037.git.peter.crosthwaite@xilinx.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The irq line status must be updated after writes to the INT_CTL and
INT_STA registers.
Signed-off-by: Beniamino Galvani <b.galvani@gmail.com>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Message-id: 1395771730-16882-8-git-send-email-b.galvani@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This implements the prescaler and source fields of the timer control
register. The source for each timer can be selected among 4 clock
inputs whose frequencies are set through model properties.
Signed-off-by: Beniamino Galvani <b.galvani@gmail.com>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Message-id: 1395771730-16882-6-git-send-email-b.galvani@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Convert the interrupt generation logic to the use of level triggered
interrupts.
Signed-off-by: Beniamino Galvani <b.galvani@gmail.com>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Message-id: 1395771730-16882-5-git-send-email-b.galvani@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The model was generating interrupts for all enabled timers after the
expiration of one of them. Avoid this by passing explicitly the timer
index to the callback function.
Signed-off-by: Beniamino Galvani <b.galvani@gmail.com>
Reviewed-by: Li Guang <lig.fnst@cn.fujitsu.com>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Message-id: 1395771730-16882-4-git-send-email-b.galvani@gmail.com
[PMM: avoid duplicate typedef of AwA10PITState]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The pending register is read-only and the value returned upon a read
reflects the state of irq input pins (interrupts are level triggered).
This patch implements such behaviour.
Signed-off-by: Beniamino Galvani <b.galvani@gmail.com>
Reviewed-by: Li Guang <lig.fnst@cn.fujitsu.com>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Message-id: 1395771730-16882-3-git-send-email-b.galvani@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This patch implements proper updating of the vector register which
should hold, according to the A10 user manual, the vector address for
the interrupt currently active on the CPU IRQ input.
Interrupt priority is not implemented at the moment and thus the first
pending interrupt is returned.
Signed-off-by: Beniamino Galvani <b.galvani@gmail.com>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Reviewed-by: Li Guang <lig.fnst@cn.fujitsu.com>
Message-id: 1395771730-16882-2-git-send-email-b.galvani@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Clean up useless 'break' statement after 'return' statement.
Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
For system mode, we may have a 64 bit CPU which is currently executing
in AArch32 state; if we're dumping CPU state to the logs we should
therefore show the correct state for the current execution state,
rather than hardwiring it based on the type of the CPU. For consistency
with how we handle translation, we leave the 32 bit dump function
as the default, and have it hand off control to the 64 bit dump code
if we're in AArch64 mode.
Reported-by: Rob Herring <rob.herring@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The AArch64 implementation of the set_pc method needs to be updated to
handle the possibility that the CPU is in AArch32 mode; otherwise there
are weird crashes when doing interprocessing in system emulation mode
when an interrupt occurs and we fail to resynchronize the 32-bit PC
with the TB we need to execute next.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
The Cortex-A15's CBAR register is actually read-only (unlike that
of the Cortex-A9). Correct our model to match the hardware.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
The Cortex-A57, like most of the other ARM cores, has a CBAR
register which defines the base address of the per-CPU
peripherals. However it has a 64-bit view as well as a
32-bit view; expand the QOM reset-cbar property from UINT32
to UINT64 so this can be specified, and implement the
32-bit and 64-bit views of a 64-bit CBAR.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Implement a subset of the Cortex-A57's implementation defined system
registers. We provide RAZ/WI or reads-as-constant/writes-ignored
implementations of the various control and syndrome reigsters.
We do not implement registers which provide direct access to and
manipulation of the L1 cache, since QEMU doesn't implement caches.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Implement the AArch64 RVBAR register, which indicates the reset
address. Since the reset address is implementation defined and
usually configurable by setting config signals in hardware, we
also provide a QOM property so it can be set at board level if
necessary.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Implement the AArch64 address translation operations.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Implement the auxiliary fault status registers AFSR0_EL1 and
AFSR1_EL1. These are present on v7 and later, and have IMPDEF
behaviour; we choose to RAZ/WI for all cores.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Many of the reginfo definitions in cp_reginfo[] use CP_ANY wildcards.
This is for a combination of reasons:
* early ARM implementations really did underdecode
* earlier versions of QEMU underdecoded and we can't tighten
this up because we don't know if guests really require this or not
* implementation convenience
For ARMv8 the architecture has tightened things up and system and
coprocessor registers are always specifically decoded. We take
advantage of this opportunity for a clean break by restricting
our CP_ANY wildcarded reginfo to pre-v8 CPUs, and providing
specifically decoded versions where necessary for v8 CPUs.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
In ARMv8 the 32 bit coprocessor ID register space is tidied up to
remove the wildcarded aliases of the MIDR and the RAZ behaviour
for the unassigned space where crm = 3..7. Make sure we don't
expose thes wildcards for v8 cores. This means we need to have
a specific implementation for REVIDR, an IMPDEF register which
may be the same as the MIDR (and which we always implement as such).
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
The AArch64 usermode 'any' CPU type was accidentally specified
with the ARM_FEATURE_THUMB2EE bit set. This is incorrect since
ARMv8 removes Thumb2EE completely. Since we never implemented
Thumb2EE anyway having the feature bit set was fairly harmless
for user-mode, but the correct thing is to not set it at all.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Implement the ISR_EL1 register. This is actually present in
ARMv7 as well but was previously unimplemented. It is a
read-only register that indicates whether interrupts are
currently pending.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Implement the AArch64 view of the ACTLR (auxiliary control
register). Note that QEMU internally tends to call this
AUXCR for historical reasons.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Implement AArch64 view of the CONTEXTIDR register.
We tighten up the condition when we flush the TLB on a CONTEXTIDR
write to avoid needlessly flushing the TLB every time on a 64
bit system (and also on a 32 bit system using LPAE, as a bonus).
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
All the AArch32 ID registers are visible from AArch64
(in addition to the AArch64-specific ID_AA64* registers).
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
For ARMv8 there are two changes to the MVFR media feature registers:
* there is a new MVFR2 which is accessible from 32 bit code
* 64 bit code accesses these via the usual sysreg instructions
rather than with a floating-point specific instruction
Implement this.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Implement exception handling for AArch64 EL1. Exceptions from AArch64 or
AArch32 EL0 are supported.
Signed-off-by: Rob Herring <rob.herring@linaro.org>
[PMM: fixed minor style nits; updated to match changes in
previous patches; added some of the simpler cases of
illegal-exception-return support]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Move arm_log_exception() into internals.h so we can use it from
helper-a64.c for the AArch64 exception entry code.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Implement the AArch64 SPSR_EL1. For compatibility with how KVM
handles SPSRs and with the architectural mapping between AArch32
and AArch64, we put this in the banked_spsr[] array in the slot
that is used for SVC in AArch32. This means we need to extend the
array from uint32_t to uint64_t, which requires some reworking
of the 32 bit KVM save/restore code.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Implement handling for the AArch64 SP_EL0 system register.
This holds the EL0 stack pointer, and is only accessible when
it's not being used as the stack pointer, ie when we're in EL1
and EL1 is using its own stack pointer. We also provide a
definition of the SP_EL1 register; this isn't guest visible
as a system register for an implementation like QEMU which
doesn't provide EL2 or EL3; however it is useful for ensuring
the underlying state is migrated.
We need to update the state fields in the CPU state whenever
we switch stack pointers; this happens when we take an exception
and also when SPSEL is used to change the bit in PSTATE which
indicates which stack pointer EL1 should use.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Add the AArch64 ELR_EL1 register.
Note that this does not live in env->cp15: for KVM migration
compatibility we need to migrate it separately rather than
as part of the system registers, because the KVM-to-userspace
interface puts it in the struct kvm_regs rather than making
them visible via the ONE_REG ioctls.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Implement AArch64 views of ESR_EL1 and FAR_EL1, and make the 32 bit
DFSR, DFAR, IFAR share state with them as architecturally specified.
The IFSR doesn't share state with any AArch64 register visible at EL1,
so just rename the state field without widening it to 64 bits.
Signed-off-by: Rob Herring <rob.herring@linaro.org>
[PMM: Minor tweaks; fix some bugs involving inconsistencies between
use of offsetof() or offsetoflow32() and struct field width]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
The ARM946 model currently uses the c5_data and c5_insn fields in the CPU
state struct to store the contents of its access permission registers.
This is confusing and a good source of bugs because for all the MMU-based
CPUs those fields are fault status and fault address registers, which
behave completely differently; they just happen to use the same cpreg
encoding. Split them out to use their own fields instead.
These registers are only present in PMSAv5 MPU systems (of which the
ARM946 is our only current example); PMSAv6 and PMSAv7 (which we have
no implementations of) handle access permissions differently. We name
the new state fields accordingly.
Note that this change fixes a bug where a data abort or prefetch abort
on the ARM946 would accidentally corrupt the access permission registers
because the interrupt handling code assumed the c5_data and c5_insn
fields were always fault status registers.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Implement the DC ZVA instruction, which clears a block of memory.
The fast path obtains a pointer to the underlying RAM via the TCG TLB
data structure so we can do a direct memset(), with fallback to a
simple byte-store loop in the slow path.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Acked-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Suppress the ID_AA64DFR0_EL1 PMUVer field, even if the CPU specific
value claims that it exists. QEMU doesn't currently implement it,
and not advertising it prevents the guest from trying to use it
and getting UNDEFs on unimplemented registers.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
---
This is arguably a hack, but otherwise Linux tries to prod
half a dozen PMU sysregs.
Add support for v8 page table walks. This supports stage 1 translations
for 4KB, 16KB and 64KB page sizes starting with 0 or 1 level.
Signed-off-by: Rob Herring <rob.herring@linaro.org>
[PMM: fix style nits, fold in 16/64K page support patch, use
arm_el_is_aa64() to decide whether to do 64 bit page table walk]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
The current A32/T32 decoder bases its "is VFP/Neon enabled?" check
on the FPSCR.EN bit. This is correct if EL1 is AArch32, but for
an AArch64 EL1 the logic is different: it must act as if FPSCR.EN
is always set. Instead, trapping must happen according to CPACR
bits for cp10/cp11; these cover all of FP/Neon, including the
FPSCR/FPSID/MVFR register accesses which FPSCR.EN does not affect.
Add support for CPACR checks (which are also required for ARMv7,
but were unimplemented because Linux happens not to use them)
and make sure they generate exceptions with the correct syndrome.
We actually return incorrect syndrome information for cases
where FP is disabled but the specific instruction bit pattern
is unallocated: strictly these should be the Uncategorized
exception, not a "SIMD disabled" exception. This should be
mostly harmless, and the structure of the A32/T32 VFP/Neon
decoder makes it painful to put the 'FP disabled?' checks in
the right places.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>