The cortex A53 TRM specifies that bits 24 and 25 of the L2CTLR register
specify the number of cores in the processor, not the total number of
cores in the system. To report this correctly on machines with multiple
CPU clusters (ARM's big.LITTLE or Xilinx's ZynqMP) we need to allow
the machine to overwrite this value. To do this let's add an optional
property.
Backports commit f9a697112ee64180354f98309a5d6b691cc8699d from qemu
The Cortex-M33 allows the system to specify the reset value of the
secure Vector Table Offset Register (VTOR) by asserting config
signals. In particular, guest images for the MPS2 AN505 board rely
on the MPS2's initial VTOR being correct for that board.
Implement a QEMU property so board and SoC code can set the reset
value to the correct value.
Backports commit 38e2a77c9d6876e58f45cabb1dd9a6a60c22b39e from qemu
Half-precision flush to zero behaviour is controlled by a separate
FZ16 bit in the FPCR. To handle this we pass a pointer to
fp_status_fp16 when working on half-precision operations. The value of
the presented FPCR is calculated from an amalgam of the two when read.
Backports commit d81ce0ef2c4f1052fcdef891a12499eca3084db7 from qemu
As cpu.h is another typically widely included file which doesn't need
full access to the softfloat API we can remove the includes from here
as well. Where they do need types it's typically for float_status and
the rounding modes so we move that to softfloat-types.h as well.
As a result of not having softfloat in every cpu.h call we now need to
add it to various helpers that do need the full softfloat.h
definitions.
Backports commit 24f91e81b65fcdd0552d1f0fcb0ea7cfe3829c19 from qemu
The v8M architecture includes hardware support for enforcing
stack pointer limits. We don't implement this behaviour yet,
but provide the MSPLIM and PSPLIM stack pointer limit registers
as reads-as-written, so that when we do implement the checks
in future this won't break guest migration.
Backports commit 57bb31568114023f67680d6fe478ceb13c51aa7d from qemu
We were previously making the system control register (SCR)
just RAZ/WI. Although we don't implement the functionality
this register controls, we should at least provide the state,
including the banked state for v8M.
Backports register related changes in commit 24ac0fb129f9ce9dd96901b2377fc6271dc55b2b from qemu
M profile cores have a similar setup for cache ID registers
to A profile:
* Cache Level ID Register (CLIDR) is a fixed value
* Cache Type Register (CTR) is a fixed value
* Cache Size ID Registers (CCSIDR) are a bank of registers;
which one you see is selected by the Cache Size Selection
Register (CSSELR)
The only difference is that they're in the NVIC memory mapped
register space rather than being coprocessor registers.
Implement the M profile view of them.
Since neither Cortex-M3 nor Cortex-M4 implement caches,
we don't need to update their init functions and can leave
the ctr/clidr/ccsidr[] fields in their ARMCPU structs at zero.
Newer cores (like the Cortex-M33) will want to be able to
set these ID registers to non-zero values, though.
Backports commit 43bbce7fbef22adf687dd84934fd0b2f8df807a8 from qemu
Change vfp.regs as a uint64_t to vfp.zregs as an ARMVectorReg.
The previous patches have made the change in representation
relatively painless.
Backports commit c39c2b9043ec59516c80f2c6f3e8193e99d04d4b from qemu
This implements emulation of the new SM4 instructions that have
been added as an optional extension to the ARMv8 Crypto Extensions
in ARM v8.2.
Backports commit b6577bcd251ca0d57ae1de149e3c706b38f21587 from qemu
This implements emulation of the new SM3 instructions that have
been added as an optional extension to the ARMv8 Crypto Extensions
in ARM v8.2.
Backports commit 80d6f4c6bbb718f343a832df8dee15329cc7686c from qemu
This implements emulation of the new SHA-512 instructions that have
been added as an optional extensions to the ARMv8 Crypto Extensions
in ARM v8.2.
Backports commit 90b827d131812d7f0a8abb13dba1942a2bcee821 from qemu
The Application Interrupt and Reset Control Register has some changes
for v8M:
* new bits SYSRESETREQS, BFHFNMINS and PRIS: these all have
real state if the security extension is implemented and otherwise
are constant
* the PRIGROUP field is banked between security states
* non-secure code can be blocked from using the SYSRESET bit
to reset the system if SYSRESETREQS is set
Implement the new state and the changes to register read and write.
For the moment we ignore the effects of the secure PRIGROUP.
We will implement the effects of PRIS and BFHFNMIS later.
Backports register-related additions in commit 3b2e934463121f06d04e4d17658a9a7cdc3717b0 from qemu
Currently armv7m_nvic_acknowledge_irq() does three things:
* make the current highest priority pending interrupt active
* return a bool indicating whether that interrupt is targeting
Secure or NonSecure state
* implicitly tell the caller which is the highest priority
pending interrupt by setting env->v7m.exception
We need to split these jobs, because v7m_exception_taken()
needs to know whether the pending interrupt targets Secure so
it can choose to stack callee-saves registers or not, but it
must not make the interrupt active until after it has done
that stacking, in case the stacking causes a derived exception.
Similarly, it needs to know the number of the pending interrupt
so it can read the correct vector table entry before the
interrupt is made active, because vector table reads might
also cause a derived exception.
Create a new armv7m_nvic_get_pending_irq_info() function which simply
returns information about the highest priority pending interrupt, and
use it to rearrange the v7m_exception_taken() code so we don't
acknowledge the exception until we've done all the things which could
possibly cause a derived exception.
Backports part of commit 6c9485188170e11ad31ce477c8ce200b8e8ce59d from qemu
In order to support derived exceptions (exceptions generated in
the course of trying to take an exception), we need to be able
to handle prioritizing whether to take the original exception
or the derived exception.
We do this by introducing a new function
armv7m_nvic_set_pending_derived() which the exception-taking code in
helper.c will call when a derived exception occurs. Derived
exceptions are dealt with mostly like normal pending exceptions, so
we share the implementation with the armv7m_nvic_set_pending()
function.
Note that the way we structure this is significantly different
from the v8M Arm ARM pseudocode: that does all the prioritization
logic in the DerivedLateArrival() function, whereas we choose to
let the existing "identify highest priority exception" logic
do the prioritization for us. The effect is the same, though.
Backports part of commit 5ede82b8ccb652382c106d53f656ed67997d76e8 from qemu
The TT instruction is going to need to look up the MMU index
for a specified security and privilege state. Refactor the
existing arm_v7m_mmu_idx_for_secstate() into a version that
lets you specify the privilege state and one that uses the
current state of the CPU.
Backports commit ec8e3340286a87d3924c223d60ba5c994549f796 from qemu
For M profile, we currently have an mmu index MNegPri for
"requested execution priority negative". This fails to
distinguish "requested execution priority negative, privileged"
from "requested execution priority negative, usermode", but
the two can return different results for MPU lookups. Fix this
by splitting MNegPri into MNegPriPriv and MNegPriUser, and
similarly for the Secure equivalent MSNegPri.
This takes us from 6 M profile MMU modes to 8, which means
we need to bump NB_MMU_MODES; this is OK since the point
where we are forced to reduce TLB sizes is 9 MMU modes.
(It would in theory be possible to stick with 6 MMU indexes:
{mpu-disabled,user,privileged} x {secure,nonsecure} since
in the MPU-disabled case the result of an MPU lookup is
always the same for both user and privileged code. However
we would then need to rework the TB flags handling to put
user/priv into the TB flags separately from the mmuidx.
Adding an extra couple of mmu indexes is simpler.)
Backports commit 62593718d77c06ad2b5e942727cead40775d2395 from qemu
The CPU ID registers ID_AA64PFR0_EL1, ID_PFR1_EL1 and ID_PFR1
have a field for reporting presence of GICv3 system registers.
We need to report this field correctly in order for Xen to
work as a guest inside QEMU emulation. We mustn't incorrectly
claim the sysregs exist when they don't, though, or Linux will
crash.
Unfortunately the way we've designed the GICv3 emulation in QEMU
puts the system registers as part of the GICv3 device, which
may be created after the CPU proper has been realized. This
means that we don't know at the point when we define the ID
registers what the correct value is. Handle this by switching
them to calling a function at runtime to read the value, where
we can fill in the GIC field appropriately.
Backports commit 96a8b92ed8f02d5e86ad380d3299d9f41f99b072 from qemu
For the SG instruction and secure function return we are going
to want to do memory accesses using the MMU index of the CPU
in secure state, even though the CPU is currently in non-secure
state. Write arm_v7m_mmu_idx_for_secstate() to do this job,
and use it in cpu_mmu_index().
Backports commit b81ac0eb6315e602b18439961e0538538e4aed4f from qemu
In cpu_mmu_index() we try to do this:
if (env->v7m.secure) {
mmu_idx += ARMMMUIdx_MSUser;
}
but it will give the wrong answer, because ARMMMUIdx_MSUser
includes the 0x40 ARM_MMU_IDX_M field, and so does the
mmu_idx we're adding to, and we'll end up with 0x8n rather
than 0x4n. This error is then nullified by the call to
arm_to_core_mmu_idx() which masks out the high part, but
we're about to factor out the code that calculates the
ARMMMUIdx values so it can be used without passing it through
arm_to_core_mmu_idx(), so fix this bug first.
Backports commit fe768788d29597ee56fc11ba2279d502c2617457 from qemu
Implement the register interface for the SAU: SAU_CTRL,
SAU_TYPE, SAU_RNR, SAU_RBAR and SAU_RLAR. None of the
actual behaviour is implemented here; registers just
read back as written.
When the CPU definition for Cortex-M33 is eventually
added, its initfn will set cpu->sau_sregion, in the same
way that we currently set cpu->pmsav7_dregion for the
M3 and M4.
Number of SAU regions is typically a configurable
CPU parameter, but this patch doesn't provide a
QEMU CPU property for it. We can easily add one when
we have a board that requires it.
Backports commit 9901c576f6c02d43206e5faaf6e362ab7ea83246 from qemu
Add the new M profile Secure Fault Status Register
and Secure Fault Address Register.
Backports commit bed079da04dd9e0e249b9bc22bca8dce58b67f40 from qemu
In the v7M architecture, there is an invariant that if the CPU is
in Handler mode then the CONTROL.SPSEL bit cannot be nonzero.
This in turn means that the current stack pointer is always
indicated by CONTROL.SPSEL, even though Handler mode always uses
the Main stack pointer.
In v8M, this invariant is removed, and CONTROL.SPSEL may now
be nonzero in Handler mode (though Handler mode still always
uses the Main stack pointer). In preparation for this change,
change how we handle this bit: rename switch_v7m_sp() to
the now more accurate write_v7m_control_spsel(), and make it
check both the handler mode state and the SPSEL bit.
Note that this implicitly changes the point at which we switch
active SP on exception exit from before we pop the exception
frame to after it.
Backports commit de2db7ec894f11931932ca78cd14a8d2b1389d5b from qemu
Now that we have a banked FAULTMASK register and banked exceptions,
we can implement the correct check in cpu_mmu_index() for whether
the MPU_CTRL.HFNMIENA bit's effect should apply. This bit causes
handlers which have requested a negative execution priority to run
with the MPU disabled. In v8M the test has to check this for the
current security state and so takes account of banking.
Backports relevant part of commit 5d4791991d4de12e83d44738417c9e964167b6e8 from qemu
Use a symbolic constant M_REG_NUM_BANKS for the array size for
registers which are banked by M profile security state, rather
than hardcoding lots of 2s.
Backports commit 4a16724f06ead684a5962477a557c26c677c2729 from qemu
Implement the BXNS v8M instruction, which is like BX but will do a
jump-and-switch-to-NonSecure if the branch target address has bit 0
clear.
This is the first piece of code which implements "switch to the
other security state", so the commit also includes the code to
switch the stack pointers around, which is the only complicated
part of switching security state.
BLXNS is more complicated than just "BXNS but set the link register",
so we leave it for a separate commit.
Backports commit fb602cb726b3ebdd01ef3b1732d74baf9fee7ec9 from qemu
Make the CFSR register banked if v8M security extensions are enabled.
Not all the bits in this register are banked: the BFSR
bits [15:8] are shared between S and NS, and we store them
in the NS copy of the register.
Backports commit 334e8dad7a109d15cb20b090131374ae98682a50 from qemu
Make the CCR register banked if v8M security extensions are enabled.
This is slightly more complicated than the other "add banking"
patches because there is one bit in the register which is not
banked. We keep the live data in the NS copy of the register,
and adjust it on register reads and writes. (Since we don't
currently implement the behaviour that the bit controls, there
is nowhere else that needs to care.)
This patch includes the enforcement of the bits which are newly
RES1 in ARMv8M.
Backports commit 9d40cd8a68cfc7606f4548cc9e812bab15c6dc28 from qemu
Make the MPU registers MPU_MAIR0 and MPU_MAIR1 banked if v8M security
extensions are enabled.
We can freely add more items to vmstate_m_security without
breaking migration compatibility, because no CPU currently
has the ARM_FEATURE_M_SECURITY bit enabled and so this
subsection is not yet used by anything.
Backports commit 62c58ee0b24eafb44c06402fe059fbd7972eb409 from qemu
Make the MPU registers MPU_MAIR0 and MPU_MAIR1 banked if v8M security
extensions are enabled.
Backports commit 4125e6feb71c810ca38f0d8e66e748b472a9cc54 from qemu
Make the FAULTMASK register banked if v8M security extensions are enabled.
Note that we do not yet implement the functionality of the new
AIRCR.PRIS bit (which allows the effect of the NS copy of FAULTMASK to
be restricted).
This patch includes the code to determine for v8M which copy
of FAULTMASK should be updated on exception exit; further
changes will be required to the exception exit code in general
to support v8M, so this is just a small piece of that.
The v8M ARM ARM introduces a notation where individual paragraphs
are labelled with R (for rule) or I (for information) followed
by a random group of subscript letters. In comments where we want
to refer to a particular part of the manual we use this convention,
which should be more stable across document revisions than using
section or page numbers.
Backports commit 42a6686b2f6199d086a58edd7731faeb2dbe7c14 from qemu
Make the PRIMASK register banked if v8M security extensions are enabled.
Note that we do not yet implement the functionality of the new
AIRCR.PRIS bit (which allows the effect of the NS copy of PRIMASK to
be restricted).
Backports commit 6d8048341995b31a77dc2e0dcaaf4e3df0e3121a from qemu
Make the BASEPRI register banked if v8M security extensions are enabled.
Note that we do not yet implement the functionality of the new
AIRCR.PRIS bit (which allows the effect of the NS copy of BASEPRI to
be restricted).
Backports commit acf949411ffb675edbfb707e235800b02e6a36f8 from qemu
