Commit Graph

273 Commits

Author SHA1 Message Date
andrew
33523e6a37 Read the CPU 0 arm64 ID registers early in initarm
We also update the kernel view early in the boot. This will allow the
use of the common kernel view in ifunc resolvers.

Sponsored by:	Innovate UK
2020-07-01 16:57:57 +00:00
andrew
22822c3e20 Move ID reading signatures to a better header
The functions to read the common user and kernel ID registers should be
in cpu.h rather than undefined.h as they are related to CPU details and
used by undefined instruction handlers.

Sponsored by:	Innovate UK
2020-07-01 16:17:51 +00:00
andrew
3addfde2b0 Create a kernel arm64 ID register view
In preparation for using ifuncs in the kernel is is useful to have a common
view of the arm64 ID registers across all CPUs. Add this and extract the
logic for finding the lower value of two fields to a new helper function.

Sponsored by:	Innovate UK
Differential Revision:	https://reviews.freebsd.org/D25463
2020-06-29 09:08:36 +00:00
andrew
1ee69c6890 Use EFI memory map to determine attributes for Acpi mappings on arm64.
AcpiOsMapMemory is used for device memory when e.g. an _INI method wants
to access physical memory, however, aarch64 pmap_mapbios is hardcoded to
writeback. Search for the correct memory type to use in pmap_mapbios.

Submitted by:	Greg V <greg_unrelenting.technology>
Differential Revision:	https://reviews.freebsd.org/D25201
2020-06-28 15:03:07 +00:00
emaste
510fa23149 arm64 armreg.h: fix TCR_TBI1 definition
Submitted by:	Greg V <greg@unrelenting.technology>
Differential Revision:	https://reviews.freebsd.org/D25411
2020-06-23 15:32:05 +00:00
andrew
aaac1b142f Add all the TCR_EL1 fields
These will be used when adding support for new Armv8 extensions.

Sponsored by:	Innovate UK
2020-06-17 11:56:10 +00:00
andrew
da219c8169 Teach the arm64 vfp.h about struct thread.
Ensure struct thread is defined in vfp.h. In some cases it is not and stops
the kernel from building.

Sponsored by:	Innovate UK
2020-06-12 10:43:21 +00:00
andrew
b128a802d7 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
2020-05-27 08:00:38 +00:00
andrew
9daa38339c Stop performing a full icache sync when the DIC and IDC flags are set
The DIC and IDC bits in the CTR_EL0 register signal to the kernel when it
can relax the instruction cache synchronisation operations. The IDC bit
means we can relax cleaning the data cache to the point of unification
while the DIC bit means we don't need to invalidate the instruction cache
for data coherence. In both cases an appropriate barrier is still needed.

For now only implement the case where both bits are set, as is the case
on the Neoverse-N1 as used in the Amazon AWS Graviton 2 CPU. Note that
this behaviour is a optional on the N1 so we may later need to implement
only one or the other bit being set.

There is a tunable to disable each flag on boot.

Testing on a 4 core Graviton 2 instance found a significant improvement
in sys and real time when running "make buildkernel -j4", with no
significant difference in user time.

Reviewed by:	markj
Sponsored by:	Innovate UK
Differential Revision:	https://reviews.freebsd.org/D24853
2020-05-19 16:04:27 +00:00
andrew
90285c8b57 Remove arm64_idcache_wbinv_range as it's unused.
Sponsored by:	Innovate UK
2020-05-15 13:33:48 +00:00
karels
b36f05da5b Add genet driver for Raspberry Pi 4B Ethernet
Add driver for Broadcom "GENET" version 5, as found in BCM-2711 on
Raspberry Pi 4B. The driver is derived in part from the bcmgenet.c
driver in NetBSD, along with bcmgenetreg.h.

Reviewed by:	manu
Obtained from:	in part from NetBSD
Relnotes:	yes, note addition
Differential Revision:	https://reviews.freebsd.org/D24436
2020-04-22 00:42:10 +00:00
cem
b4fc99e12c Expand generic subword atomic primitives
The goal of this change is to make the atomic_load_acq_{8,16},
atomic_testandset{,_acq}_long, and atomic_testandclear_long primitives
available in MI-namespace.

The second goal is to get this draft out of my local tree, as anything that
requires a full tinderbox is a big burden out of tree.  MD specifics can be
refined individually afterwards.

The generic implementations may not be ideal for your architecture; feel
free to implement better versions.  If no subword_atomic definitions are
needed, the include can be removed from your arch's machine/atomic.h.
Generic definitions are guarded by defined macros of the same name.  To
avoid picking up conflicting generic definitions, some macro defines are
added to various MD machine/atomic.h to register an existing implementation.

Include _atomic_subword.h in arm and arm64 machine/atomic.h.

For some odd reason, KCSAN only generates some versions of primitives.
Generate the _acq variants of atomic_load.*_8, atomic_load.*_16, and
atomic_testandset.*_long.  There are other questionably disabled primitives,
but I didn't run into them, so I left them alone.  KCSAN is only built for
amd64 in tinderbox for now.

Add atomic_subword implementations of atomic_load_acq_{8,16} implemented
using masking and atomic_load_acq_32.

Add generic atomic_subword implementations of atomic_testandset_long(),
atomic_testandclear_long(), and atomic_testandset_acq_long(), using
atomic_fcmpset_long() and atomic_fcmpset_acq_long().

On x86, add atomic_testandset_acq_long as an alias for
atomic_testandset_long.

Reviewed by:	kevans, rlibby (previous versions both)
Differential Revision:	https://reviews.freebsd.org/D22963
2020-03-25 23:12:43 +00:00
andrew
cf07ed23e4 Add more are64 special register fields
Obtained from:	https://github.com/FreeBSD-UPB/freebsd
2020-03-06 16:00:35 +00:00
andrew
3620fb0b18 Update the hypervisor registers
- Add more registers needed by bhyve [1]
 - Move EL2 registers from armreg.h to hypervisor.h
 - Add the register name to hypervisor.h

Obtained from:	https://github.com/FreeBSD-UPB/freebsd [1]
2020-03-06 14:46:50 +00:00
andrew
1da2fbfb53 Mark the arm64 machdep.h as kernel only
None of this is useful for userspace.

Sponsored by:	Innovate UK
2020-03-05 10:52:16 +00:00
andrew
4a6509d155 Fix the spelling of aliasing.
Sponsored by:	Innovate UK
2020-03-03 15:31:40 +00:00
andrew
dbed753b3f Move the arm64 cache identification to identcpu.c
This allows us to call it on a per-CPU basis and to warn if the details
are different across CPUs.

While here read the L1 I-Cache type and store this for use later by pmap.

Sponsored by:	Innovate UK
2020-03-03 15:25:01 +00:00
andrew
444460945e Fix the spelling of the VIPT cache type field
Sponsored by:	Innovate UK
2020-03-03 12:50:45 +00:00
andrew
2b5b74c14d Store the boot exception level on arm64 so it can be queried later
A hypervisor, e.g. bhyve, will need to know what exception levelthe kernel
was in when it started booting. If it was EL2 we can then enable said
hypervisor.

Store the boot exception level and allow the kernel to later query it.

Obtained from:	https://github.com/FreeBSD-UPB/freebsd (earlier version)
Sponsored by:	Innovate UK
2020-03-03 08:28:16 +00:00
andrew
246dc0cc91 Generalise the arm64 ASID allocator.
The requirements of an Address Space ID allocator and a Virtual Machine ID
allocator are similar. Generalise the former code so it can be used with
the latter.

Reviewed by:	alc (previous version)
Sponsored by:	Innovate UK
Differential Revision:	https://reviews.freebsd.org/D23831
2020-02-26 11:50:24 +00:00
andrew
b28fc4c314 Start to support multiple stages in the arm64 pmap.
On arm64 the stage 1 and stage 2 pte formats are similar enough we can
reuse the pmap code for both. As they are only similar and not identical
we need to know if we are managing stage 1 or stage 2 tables.

Add an enum to store this information and a check to make sure it is
set to stage 1 when we manage stage 1 pte fields.

Sponsored by:	Innovate UK
Differential Revision:	https://reviews.freebsd.org/D23830
2020-02-26 11:47:24 +00:00
andrew
6cb95687b2 Add more arm64 CTR_EL0 register fields
While here make the _SIZE macros return the size in bytes, not the log2
of the size

Sponsored by:	Innovate UK
2020-02-26 11:29:03 +00:00
andrew
dcc60239b6 Split out the stage 1 pte bits and add the stage 2 bits
In preperation for adding bhyve support to arm64 we need to split the
stage 1 and stage 2 pte fields to allow future changes to create stage 2
page tables.

MFC after:	1 month
Sponsored by:	Innovate UK
Differential Revision:	https://reviews.freebsd.org/D23669
2020-02-24 16:45:31 +00:00
markj
80f1eda869 Define MAXCPU consistently between the kernel and KLDs.
This reverts r177661.  The change is no longer very useful since
out-of-tree KLDs will be built to target SMP kernels anyway.  Moveover
it breaks the KBI in !SMP builds since cpuset_t's layout depends on the
value of MAXCPU, and several kernel interfaces, notably
smp_rendezvous_cpus(), take a cpuset_t as a parameter.

PR:		243711
Reviewed by:	jhb, kib
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D23512
2020-02-05 19:08:21 +00:00
markj
73a1608d91 Dynamically select LSE-based atomic(9)s on arm64.
Once all CPUs are online, determine if they all support LSE atomics and
set lse_supported to indicate this.  For now the atomic(9)
implementations are still always inlined, though it would be preferable
to create out-of-line functions to avoid text bloat.  This was not done
here since big.little systems exist in which some CPUs implement LSE
while others do not, and ifunc resolution must occur well before this
scenario can be detected.  It does seem unlikely that FreeBSD will
ever run on such platforms, however, so converting atomic(9) to use
ifuncs is probably a good next step.

Add a LSE_ATOMICS arm64 kernel configuration option to unconditionally
select LSE-based atomic(9) implementations when the target system is
known.

Reviewed by:	andrew, kib
MFC after:	1 month
Sponsored by:	The FreeBSD Foundation, Amazon (hardware)
Differential Revision:	https://reviews.freebsd.org/D23325
2020-02-03 18:23:50 +00:00
markj
1f66354182 Add LSE-based atomic(9) implementations.
These make use of the cas*, ld* and swp instructions added in ARMv8.1.
Testing shows them to be significantly more performant than LL/SC-based
implementations.

No functional change here since the wrappers still unconditionally
select the _llsc variants.

Reviewed by:	andrew, kib
MFC after:	1 month
Submitted by:	Ali Saidi <alisaidi@amazon.com> (original version)
Differential Revision:	https://reviews.freebsd.org/D23324
2020-02-03 18:23:35 +00:00
markj
4200d8d829 Add wrappers for arm64 atomics.
Add a _llsc suffix for the existing LL/SC-based implementations and add
trivial wrappers.  This is in preparation for supporting LSE-based
atomic(9) implementations.

No functional change intended.

Reviewed by:	andrew, kib
MFC after:	1 month
Sponsored by:	The FreeBSD Foundation, Amazon (hardware)
Differential Revision:	https://reviews.freebsd.org/D23323
2020-02-03 18:23:14 +00:00
markj
ef0260fb17 Provide a single implementation for each of the arm64 atomic(9) ops.
Parameterize the macros by type width as well as acq/rel semantics.
This makes modifying the implementations much less tedious and
error-prone and makes it easier to support alternate LSE-based
implementations.  No functional change intended.

Reviewed by:	andrew, kib
MFC after:	1 month
Sponsored by:	The FreeBSD Foundation, Amazon (hardware)
Differential Revision:	https://reviews.freebsd.org/D23322
2020-02-03 18:22:59 +00:00
markj
9838560238 Print missing ID_AA64PFR{0,1}_EL1 register fields.
MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D23213
2020-01-23 16:10:38 +00:00
andrew
f2c97d8528 Add atomic_testandset/clear on arm64.
These will reportedly be used in future uma changes.

MFC after:	2 weeks
Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D23019
2020-01-09 10:26:36 +00:00
andrew
338a93d2b7 Add more Arm arm64 CPU identification values
- Add all the Cortex-A CPU ID register values I can find.
 - Add the Neoverse-N1 ID regiser value [1]
 - Sort macros by register value.

PR:		243065
Submitted by:	Ali Saidi <alisaidi AT amazon.com> [1]
Sponsored by:	DARPA, AFRL (other than [1])
2020-01-06 20:57:59 +00:00
andrew
9eaa615b30 Add the 8 and 16 bit atomic load/store functions with a barrier on arm64.
Reviewed by:	cem
MFC after:	2 weeks
Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D22966
2020-01-03 10:03:36 +00:00
alc
e10b156363 Determine whether the MMU hardware is capable of updating a page table
entry's access flag and dirty state, and enable this feature when it's
available.

Ensure that we don't overlook a dirty state update that is concurrent
with a call to pmap_enter().  (Previously, all dirty state updates would
have occurred with the containing pmap's lock held, so a page table entry's
dirty state could not have changed while pmap_enter() held that same lock.)

Reviewed by:	andrew, markj
MFC after:	2 weeks
Differential Revision:	https://reviews.freebsd.org/D22907
2019-12-30 20:30:31 +00:00
andrew
29fb48ace4 Stop speculation past an eret instruction
On arm64 the eret instruction is used to return from an exception handler.
Some implementations may speculate past this instruction into the next
function. As the user may control many registers in these functions add
a synchronisation barrier sequence after the eret instruction to stop these
CPUs from speculating out of the exception handler.

PR:		242676
Submitted by:	Anthony Steinhauser <asteinhauser@google.com> (previous version)
MFC after:	1 week
2019-12-19 08:52:16 +00:00
andrew
34e92dc3f5 Add comments and macros to the tcr_el1 setting code to help understand it.
This code is non-obvious when reading for the first time. To help with
understanding of it add comments explaining what it's doing.

While here use macros from armreg.h rather than magic numbers.

Sponsored by:	DARPA, AFRL
2019-12-12 18:27:54 +00:00
markj
e0995c18f6 Introduce vm_page_astate.
This is a 32-bit structure embedded in each vm_page, consisting mostly
of page queue state.  The use of a structure makes it easy to store a
snapshot of a page's queue state in a stack variable and use cmpset
loops to update that state without requiring the page lock.

This change merely adds the structure and updates references to atomic
state fields.  No functional change intended.

Reviewed by:	alc, jeff, kib
Sponsored by:	Netflix, Intel
Differential Revision:	https://reviews.freebsd.org/D22650
2019-12-10 18:14:50 +00:00
mmel
1f44036356 Add support for booting kernel directly from U-Boot using booti command.
In some cases, like is locked bootstrap or device's inability to boot from
removable media, we cannot use standard boot sequence and is necessary to
boot kernel directly from U-Boot.

Discussed with:	jhibbits
MFC after:	1 month
Differential Revision:	https://reviews.freebsd.org/D13861
2019-12-07 16:14:23 +00:00
imp
a476ba06d5 Regularize my copyright notice
o Remove All Rights Reserved from my notices
o imp@FreeBSD.org everywhere
o regularize punctiation, eliminate date ranges
o Make sure that it's clear that I don't claim All Rights reserved by listing
  All Rights Reserved on same line as other copyright holders (but not
  me). Other such holders are also listed last where it's clear.
2019-12-04 16:56:11 +00:00
jhibbits
f611a81b2f revert r354714 "Boot arm64 kernel using booti command from U-boot."
After discussing with mmel@, it was clear this is insufficient to address
all the needs.  mmel@ will commit his original patch, from
https://reviews.freebsd.org/D13861, and the additions needed from r354714
will be made afterward.

Requested by:	mmel
Sponsored by:	Juniper Networks, Inc.
2019-12-02 15:07:06 +00:00
andrew
e95c204297 Add kcsan_md_unsupported from NetBSD.
It's used to ignore virtual addresses that may have a different physical
address depending on the CPU.

Sponsored by:	DARPA, AFRL
2019-11-21 13:22:23 +00:00
andrew
6e5970c8f4 Port the NetBSD KCSAN runtime to FreeBSD.
Update the NetBSD Kernel Concurrency Sanitizer (KCSAN) runtime to work in
the FreeBSD kernel. It is a useful tool for finding data races between
threads executing on different CPUs.

This can be enabled by enabling KCSAN in the kernel config, or by using the
GENERIC-KCSAN amd64 kernel. It works on amd64 and arm64, however the later
needs a compiler change to allow -fsanitize=thread that KCSAN uses.

Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D22315
2019-11-21 11:22:08 +00:00
andrew
0fe49e2eed Fix the definition of bus_space_read_stream_8 on arm64.
This is currently unused, however will be when the Kernel Concurrency
Sanitizer (KCSAN) is imported from NetBSD.

Sponsored by:	DARPA, AFRL
2019-11-19 10:57:44 +00:00
jhibbits
399f6e87ff Boot arm64 kernel using booti command from U-boot.
Summary:
Boot arm64 kernel using booti command from U-boot. booti can relocate initrd
image into higher ram addresses, therefore align the initrd load address to 1GiB
and create VA = PA map for it. Create L2 pagetable entries to copy the initrd
image into KVA.
(parts of the code in https://reviews.freebsd.org/D13861 was referred and used
as appropriate)

Submitted by:	Siddharth Tuli <siddharthtuli_gmail.com>
Reviewed by:	manu
Sponsored by:	Juniper Networks, Inc
Differential Revision: https://reviews.freebsd.org/D22255
2019-11-14 21:58:40 +00:00
andrew
c598107ad1 Add more 8 and 16 bit variants of the the atomic(9) functions on arm64.
These are direct copies of the 32 bit functions, adjusted ad needed.
While here fix atomic_fcmpset_16 to use the valid load and store exclusive
instructions.

Sponsored by:	DARPA, AFRL
2019-11-07 17:34:44 +00:00
andrew
3de5e49155 Move the struct debug_monitor_state out of _KERNEL.
Some userland libraries incude machine/pcb.h and this needs the full
definition of struct debug_monitor_state. To allow this to work move
stuct debug_monitor_state out of the _KERNEL guard.

Sponsored by:	DARPA, AFRL
2019-11-03 22:17:49 +00:00
alc
2a4c328a15 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
2019-11-03 17:45:30 +00:00
andrew
a7095edbfd Add support for setting hardware breakpoints from ptrace on arm64.
Implement get/fill_dbregs on arm64. This is used by ptrace with the
PT_GETDBREGS and PT_SETDBREGS requests. It allows userspace to set hardware
breakpoints.

The struct dbreg is based on Linux to ease adding hardware breakpoint
support to debuggers.

Reviewed by:	jhb
Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D22195
2019-11-03 15:42:08 +00:00
andrew
50cea160e6 Allow exceptions to be masked when in userspace
We may want to mask exceptions when in userspace. This was previously
impossible as threads are created with all exceptions unmasked and
signals expected userspace to mask any. Fix these by copying the
mask state on thread creation and allow exceptions to be masked on
signal return, as long as they don't change.

Sponsored by:	DARPA, AFRL
2019-10-30 14:05:50 +00:00
andrew
a8fc8da063 Allow the userspace ID register fields to be read from the kernel
To allow consistent values to be used in both the kernel and userspace
create a function for these to be read from the kernel. They use a newly
created macro with the name of the ID register to read. For now there is
redundant information in the user_regs array as it still holds the CRm and
Op2 values, however this will be fixed in a later change.

This will be used by ptrace to allow hardware breakpoints in userspace.

Sponsored by:	DARPA, AFRL
2019-10-30 13:45:40 +00:00
andrew
4b3c23bef9 Move the MRS instruction decode macros to armreg.h
These instructions are used to access the registers described in armreg.h,
and will be used in a future change to create a per-register identification
macro.

Sponsored by:	DARPA, AFRL
2019-10-30 12:33:36 +00:00