kexec: Introduce basic arm64 support

This works on older arm64 platforms, but may not work with arm64 devices
using GICv3, due to a quirk in the GICv3, where some registers are
write-once.

Most of

kexec: Introduce basic arm64 support

This works on older arm64 platforms, but may not work with arm64 devices
using GICv3, due to a quirk in the GICv3, where some registers are
write-once.

Most of the kexec reboot work on arm64 can be done entirely in C code,
by disabling the MMU, as the kernel is carved out of the vm_phys_segs
array, so cannot be overwritten.

Reviewed by: andrew
Sponsored by: Juniper Networks, Inc.
Differential Revision: https://reviews.freebsd.org/D51621

show more ...

arm64: Delete stale comment

Fixes: 078a69abcbb8 ("Use a uint64_t to store the arm64 mpidr")

sys: Remove $FreeBSD$: one-line .h pattern

Remove /^\s*\*+\s*\$FreeBSD\$.*$\n/

pcpu: Remove unused definitions of ALT_STACK_SIZE

This was added originally for the sparc64 port and apparently copied to
other platforms. No functional change intended.

MFC after: 1 week

arm64 lib32: prepare arm64 headers to redirect to arm

In order to compile lib32 libraries and other 32-bit code on arm64,
<machine/foo.h> needs to be redirected to an arm header rather
than arm64 wh

arm64 lib32: prepare arm64 headers to redirect to arm

In order to compile lib32 libraries and other 32-bit code on arm64,
<machine/foo.h> needs to be redirected to an arm header rather
than arm64 when building with -m32. Ifdef the arm64 headers that
are installed in /usr/include/machine and used by user-level software
(including references from /usr/include/*.h) so that if __arm__ is
defined when including the arm64 version, <arm/foo.h> is included
rather than using the rest of the file's contents. Some arm headers
had no arm64 equivalent; headers were added just to do the redirection.
These files use #error if __arm__ is not defined to guard against
confusion. Also add an include/arm Makefile, and modify Makefiles
as needed to install everything, including the arm files in
/usr/include/arm. fenv.h comes from lib/msun/arm/fenv.h.

The new arm64 headers are:
acle-compat.h
cpuinfo.h
sysreg.h

Reviewed by: jrtc27, imp
Differential Revision: https://reviews.freebsd.org/D40944

show more ...

Use a uint64_t to store the arm64 mpidr

Use a single uint64_t to hole the mpidr register as we can break the
KBI on 14. Keep the macro so code can still be MFCd to 13.

Sponsored by: Arm Ltd

Store mpidr as a 64-bit value on arm64

The mpidr register is 64 bit on arm64 and 32 bit on arm. Fix this by
extending the arm64 definition to include the top 32 bits.

To preserve KBI when MFCing sp

Store mpidr as a 64-bit value on arm64

The mpidr register is 64 bit on arm64 and 32 bit on arm. Fix this by
extending the arm64 definition to include the top 32 bits.

To preserve KBI when MFCing split the value into two 32 bit values.
This will be cleaned up later only on main.

Reviewed by: bz
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D36346

show more ...

Make the arm64 get_pcpu a function again

We assume the pointer returned from get_pcpu will be consistent even
if the thread is moved to a new CPU. Fix this by partially reverting
63c858a04d565 to ma

Make the arm64 get_pcpu a function again

We assume the pointer returned from get_pcpu will be consistent even
if the thread is moved to a new CPU. Fix this by partially reverting
63c858a04d565 to make get_pcpu a function again.

Sponsored by: The FreeBSD Foundation

show more ...

Remove PCPU_INC

e4b8deb22227 removed the last in-tree uses of PCPU_INC(). Its
potential benefit is also practically nonexistent. Non-x86
platforms already implement it as PCPU_ADD(..., 1), and acc

Remove PCPU_INC

e4b8deb22227 removed the last in-tree uses of PCPU_INC(). Its
potential benefit is also practically nonexistent. Non-x86
platforms already implement it as PCPU_ADD(..., 1), and according
to [0] there are no recent x86 processors for which the 'inc'
instruction provides a performance benefit over the equivalent
memory-operand form of the 'add' instruction. The only remaining
benefit of 'inc' is smaller instruction size, which in this case
is inconsequential given the limited number of per-CPU data consumers.

[0]: https://www.agner.org/optimize/instruction_tables.pdf

Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D29308

show more ...

Switch the arm64 pcpu to a global register variable

This removes an unneeded instruction to move the pointer from x18 to a
temporary register.

Reviewed by: emaste
Sponsored by: Innovate UK
Differen

Switch the arm64 pcpu to a global register variable

This removes an unneeded instruction to move the pointer from x18 to a
temporary register.

Reviewed by: emaste
Sponsored by: Innovate UK
Differential Revision: https://reviews.freebsd.org/D26971

show more ...

Simplify startup of secondary cores and store MPIDR register to pcpu.

- record MPIDR for all started cores in pcpu, they will be used as link
between physical locality of given core, ID in exter

Simplify startup of secondary cores and store MPIDR register to pcpu.

- record MPIDR for all started cores in pcpu, they will be used as link
between physical locality of given core, ID in external description
(FDT or ACPI) and cupid.
- because of above, cpuid can (and should) be freely assigned, only boot
CPU must have cpuid 0. Simplify startup code according this.

Please note that pure cpuid is not sufficient instrument to hold any
information about core or cluster topology, nor to determistically iterate
over subpart of cores in CPU (iterate over all cores in single cluster for
example). Situation is more complicated by fact that PSCI can reject start
of core without reporting error (because power budget for example), or by
fact that is possible that we booted on non-first core in cluster (thus with
cpuid 0 assigned to random core).

Given cores topology should be exhibited to other parts of system
(for example to scheduler for big.little or multicluster systems) by using
smp_topo interface.

Differential Revision: https://reviews.freebsd.org/D13863

show more ...

Support creating and using arm64 pmap at stage 2

Add minimal support for creating stage 2 IPA -> PA mappings. For this we
need to:

- Create a new vmid set to allocate a vmid for each Virtual Machi

Support creating and using arm64 pmap at stage 2

Add minimal support for creating stage 2 IPA -> PA mappings. For this we
need to:

- Create a new vmid set to allocate a vmid for each Virtual Machine
- Add the missing stage 2 attributes
- Use these in pmap_enter to create a new mapping
- Handle stage 2 faults

The vmid set is based on the current asid set that was generalised in
r358328. It adds a function pointer for bhyve to use when the kernel needs
to reset the vmid set. This will need to call into EL2 and invalidate the
TLB.

The stage 2 attributes have been added. To simplify setting these fields
two new functions are added to get the memory type and protection fields.
These are slightly different on stage 1 and stage 2 tables. We then use
them in pmap_enter to set the new level 3 entry to be stored.

The D-cache on all entries is cleaned to the point of coherency. This is
to allow the data to be visible to the VM. To allow for userspace to load
code when creating a new executable entry an invalid entry is created. When
the VM tried to use it the I-cache is invalidated. As the D-cache has
already been cleaned this will ensure the I-cache is synchronised with the
D-cache.

When the hardware implements a VPIPT I-cache we need to either have the
correct VMID set or invalidate it from EL2. As the host kernel will have
the wrong VMID set we need to call into EL2 to clean it. For this a second
function pointer is added that is called when this invalidation is needed.

Sponsored by: Innovate UK
Differential Revision: https://reviews.freebsd.org/D23875

show more ...

Utilize ASIDs to reduce both the direct and indirect costs of context
switching. The indirect costs being unnecessary TLB misses that are
incurred when ASIDs are not used. In fact, currently, when

Utilize ASIDs to reduce both the direct and indirect costs of context
switching. The indirect costs being unnecessary TLB misses that are
incurred when ASIDs are not used. In fact, currently, when we perform a
context switch on one processor, we issue a broadcast TLB invalidation that
flushes the TLB contents on every processor.

Mark all user-space ("ttbr0") page table entries with the non-global flag so
that they are cached in the TLB under their ASID.

Correct an error in pmap_pinit0(). The pointer to the root of the page
table was being initialized to the root of the kernel-space page table
rather than a user-space page table. However, the root of the page table
that was being cached in process 0's md_l0addr field correctly pointed to a
user-space page table. As long as ASIDs weren't being used, this was
harmless, except that it led to some unnecessary page table switches in
pmap_switch(). Specifically, other kernel processes besides process 0 would
have their md_l0addr field set to the root of the kernel-space page table,
and so pmap_switch() would actually change page tables when switching
between process 0 and other kernel processes.

Implement a workaround for Cavium erratum 27456 affecting ThunderX machines.
(I would like to thank andrew@ for providing the code to detect the affected
machines.)

Address integer overflow in the definition of TCR_ASID_16.

Setup TCR according to the PARange and ASIDBits fields from
ID_AA64MMFR0_EL1. Previously, TCR_ASID_16 was unconditionally set.

Modify build_l1_block_pagetable so that lower attributes, such as ATTR_nG,
can be specified as a parameter.

Eliminate some unused code.

Earlier versions were tested to varying degrees by: andrew, emaste, markj

MFC after: 3 weeks
Differential Revision: https://reviews.freebsd.org/D21922

show more ...

Update the debug monitor handling to work after userspace has started

The debug monitor register state is now stored in a struct and updated
when required. Currently there is only a kernel state, ho

Update the debug monitor handling to work after userspace has started

The debug monitor register state is now stored in a struct and updated
when required. Currently there is only a kernel state, however a
per-process state will be added in a future change.

Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D22128

show more ...

Merge ^/head r336870 through r337285, and resolve conflicts.

kexec: Introduce basic arm64 support

This works on older arm64 platforms, but may not work with arm64 devices
using GICv3, due to a quirk in the GICv3, where some registers are
write-once.

Most of

kexec: Introduce basic arm64 support

This works on older arm64 platforms, but may not work with arm64 devices
using GICv3, due to a quirk in the GICv3, where some registers are
write-once.

Most of the kexec reboot work on arm64 can be done entirely in C code,
by disabling the MMU, as the kernel is carved out of the vm_phys_segs
array, so cannot be overwritten.

Reviewed by: andrew
Sponsored by: Juniper Networks, Inc.
Differential Revision: https://reviews.freebsd.org/D51621

show more ...

arm64: Delete stale comment

Fixes: 078a69abcbb8 ("Use a uint64_t to store the arm64 mpidr")

sys: Remove $FreeBSD$: one-line .h pattern

Remove /^\s*\*+\s*\$FreeBSD\$.*$\n/

pcpu: Remove unused definitions of ALT_STACK_SIZE

This was added originally for the sparc64 port and apparently copied to
other platforms. No functional change intended.

MFC after: 1 week

arm64 lib32: prepare arm64 headers to redirect to arm

In order to compile lib32 libraries and other 32-bit code on arm64,
<machine/foo.h> needs to be redirected to an arm header rather
than arm64 wh

arm64 lib32: prepare arm64 headers to redirect to arm

In order to compile lib32 libraries and other 32-bit code on arm64,
<machine/foo.h> needs to be redirected to an arm header rather
than arm64 when building with -m32. Ifdef the arm64 headers that
are installed in /usr/include/machine and used by user-level software
(including references from /usr/include/*.h) so that if __arm__ is
defined when including the arm64 version, <arm/foo.h> is included
rather than using the rest of the file's contents. Some arm headers
had no arm64 equivalent; headers were added just to do the redirection.
These files use #error if __arm__ is not defined to guard against
confusion. Also add an include/arm Makefile, and modify Makefiles
as needed to install everything, including the arm files in
/usr/include/arm. fenv.h comes from lib/msun/arm/fenv.h.

The new arm64 headers are:
acle-compat.h
cpuinfo.h
sysreg.h

Reviewed by: jrtc27, imp
Differential Revision: https://reviews.freebsd.org/D40944

show more ...

Use a uint64_t to store the arm64 mpidr

Use a single uint64_t to hole the mpidr register as we can break the
KBI on 14. Keep the macro so code can still be MFCd to 13.

Sponsored by: Arm Ltd

Store mpidr as a 64-bit value on arm64

The mpidr register is 64 bit on arm64 and 32 bit on arm. Fix this by
extending the arm64 definition to include the top 32 bits.

To preserve KBI when MFCing sp

Store mpidr as a 64-bit value on arm64

The mpidr register is 64 bit on arm64 and 32 bit on arm. Fix this by
extending the arm64 definition to include the top 32 bits.

To preserve KBI when MFCing split the value into two 32 bit values.
This will be cleaned up later only on main.

Reviewed by: bz
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D36346

show more ...

Make the arm64 get_pcpu a function again

We assume the pointer returned from get_pcpu will be consistent even
if the thread is moved to a new CPU. Fix this by partially reverting
63c858a04d565 to ma

Make the arm64 get_pcpu a function again

We assume the pointer returned from get_pcpu will be consistent even
if the thread is moved to a new CPU. Fix this by partially reverting
63c858a04d565 to make get_pcpu a function again.

Sponsored by: The FreeBSD Foundation

show more ...

Remove PCPU_INC

e4b8deb22227 removed the last in-tree uses of PCPU_INC(). Its
potential benefit is also practically nonexistent. Non-x86
platforms already implement it as PCPU_ADD(..., 1), and acc

Remove PCPU_INC

e4b8deb22227 removed the last in-tree uses of PCPU_INC(). Its
potential benefit is also practically nonexistent. Non-x86
platforms already implement it as PCPU_ADD(..., 1), and according
to [0] there are no recent x86 processors for which the 'inc'
instruction provides a performance benefit over the equivalent
memory-operand form of the 'add' instruction. The only remaining
benefit of 'inc' is smaller instruction size, which in this case
is inconsequential given the limited number of per-CPU data consumers.

[0]: https://www.agner.org/optimize/instruction_tables.pdf

Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D29308

show more ...

Switch the arm64 pcpu to a global register variable

This removes an unneeded instruction to move the pointer from x18 to a
temporary register.

Reviewed by: emaste
Sponsored by: Innovate UK
Differen

Switch the arm64 pcpu to a global register variable

This removes an unneeded instruction to move the pointer from x18 to a
temporary register.

Reviewed by: emaste
Sponsored by: Innovate UK
Differential Revision: https://reviews.freebsd.org/D26971

show more ...