They originated in the original Octeon port. They weren't present, as
far as I can tell, on the projects/mips branch until after this
point. They were in the original Octeon port in code picked up from
the vendor, who I've been able to find out trolling old email put them
there to get around an SMP problem that most likely was fixed in other
ways.
NetBSD and Linux don't have these, except for some specific uses of
SYNC on the alchemy parts (which we don't support, but even if we did
it is only a specific case and would be specifically coded
anyway). This is true of the current Linux code, as well as one old
version I polled.
I looked back at the old R12000, R8000, R6000, R4000, R4400 errata
that I have, and could find no mention of SYNC needing NOPs for
silicon bugs (although plenty of other cases where NOPs and other
contortions were needed).
An Google search turned up no old mailing list discussions on this on
Linux, NetBSD or FreeBSD (except the disussion that kicked off these
studies).
I've test booted this on my Octeon Plus eval board and survived a
buildworld. Adrian Chadd reports that this patch has no ill effects on
the Ahteros platforms he tested it on.
I conclude it is safe to just remove the NOPs. But added
__MIPS_PLATFORM_SYNC_NOPS as a failsafe in case we find some platform
where these are, in fact, required.
Reviewed by: adrian@
This is an AR7240 based device with an AR9285 on-board.
I've tested the initial boot and wifi support; however at the moment
the ethernet switch driver doesn't seem to be picking up carrier on the
active ethernet port. Basic flood pinging works however, so I think
we're on the right track.
Thank you to Adrian Woodley <adrian@diskworld.com.au> for purchasing me
one of these devices to bootstrap FreeBSD-HEAD on.
Issues were noted by Bruce Evans and are present on all architectures.
On i386, a counter fetch should use atomic read of 64bit value,
otherwise carry from the increment on other CPU could be lost for the
given fetch, making error of 2^32. If 64bit read (cmpxchg8b) is not
available on the machine, it cannot be SMP and it is enough to disable
preemption around read to avoid the split read.
On x86 the counter increment is not atomic on purpose, which makes it
possible for the store of the incremented result to override just
zeroed per-cpu slot. The effect would be a counter going off by
arbitrary value after zeroing. Perform the counter zeroing on the
same processor which does the increments, making the operations
mutually exclusive. On i386, same as for the fetching, if the
cmpxchg8b is not available, machine is not SMP and we disable
preemption for zeroing.
PowerPC64 is treated the same as amd64.
For other architectures, the changes made to allow the compilation to
succeed, without fixing the issues with zeroing or fetching. It
should be possible to handle them by using the 64bit loads and stores
atomic WRT preemption (assuming the architectures also converted from
using critical sections to proper asm). If architecture does not
provide the facility, using global (spin) mutex would be non-optimal
but working solution.
Noted by: bde
Sponsored by: The FreeBSD Foundation
Provide both __sync_*-style and __atomic_*-style functions that perform
the atomic operations on ARMv5 by using Restartable Atomic Sequences.
While there, clean up some pieces of code where it's sufficient to use
regular uint32_t to store register contents and don't need full reg_t's.
Also sync this back to the MIPS code.
After pushing in my fix for the 2 byte functions, I realized that the
functions for 1 and 2 byte operations had become identical. Reduce the
code size by merging the functions for 1 and 2 byte operations together.
While there, slightly improve variable naming and comments.
This is based on the AR933x (Hornet) SoC from Qualcomm Atheros.
It's a much nicer board to do development on - 64MB RAM, 16MB flash.
The development board breaks out the GPIO pins, ethernet, serial (via
a USB<->RS232 chip), USB host and of course a small wifi antenna.
Everything but the wifi works thus far.
Even though I tested the 1-byte operations on arbitrarily aligned bytes,
it seems I did not do this for the 2-byte operations.
Create easy to read functions that are used to get/put bytes and
halfwords in words. To keep the compiler happy, explicitly read two
bytes into a union to obtain a 16-bit value.
To make <stdatomic.h> work on MIPS (and ARM) using GCC, we need to
provide implementations of the __sync_*() functions. I already added
these functions for 4 and 8 byte types to libcompiler-rt some time ago,
based on top of <machine/atomic.h>.
Unfortunately, <machine/atomic.h> only provides a subset of the features
needed to implement <stdatomic.h>. This means that in some cases we had
to do compare-and-exchange calls in loops, where a simple ll/sc would
suffice.
Also implement these functions for 1 and 2 byte types. MIPS only
provides ll/sc instructions for 4 and 8 byte types, but this is of
course no limitation. We can simply load 4 bytes and use some bitmask
tricks to modify only the bytes affected.
Discussed on: mips, arch
Tested with: QEMU
this file is in FreeBSD. There's formality to this that hasn't
happened and Juniper is perfectly fine with being the holder.
Discussed with: eadler, imp, jhb
ownership to the FreeBSD foundation for the years this file has been in
the FreeBSD repository.
This file was originally created by Juniper as part of upgrading to FreeBSD
4.10 (which had no MIPS support) and held functions found on other machines
It grew actual functionality over time. The functionaliy was copied from
other architectures and ported to MIPS on a as-needed basis.
Approved by: Mark Baushke (Juniper IP)
Approved by: Megan Sugiyama (Juniper legal)
Pointed out by: jmallett@
Requested by: core (jhb@)
o Relax locking assertions for pmap_enter_object() and add them also
to architectures that currently don't have any
o Introduce VM_OBJECT_LOCK_DOWNGRADE() which is basically a downgrade
operation on the per-object rwlock
o Use all the mechanisms above to make vm_map_pmap_enter() to work
mostl of the times only with readlocks.
Sponsored by: EMC / Isilon storage division
Reviewed by: alc
Convert the structures to C99 style initialisation, which makes it
a lot easier to check that all of them are set and to generate a
derived template from them.
Sponsored by: DARPA, AFRL
MFC after: 2 weeks
Until an ADM6996 driver shows up, this allows for the two switch
ports to be used.
Submitted by: Luiz Otavio O Souza <loos.br@gmail.com>
Reviewed by: ray
order to match the MAXCPU concept. The change should also be useful
for consolidation and consistency.
Sponsored by: EMC / Isilon storage division
Obtained from: jeff
Reviewed by: alc
Remove #define to get kludges that asm.h used to define
Move clever macros to access assembler instructions to trap.c
Remove __ASSEMBLER__ ifdefs in regdef.h: they aren't needed anymore.
expand the %sccs.include.redist.c% directive with the standard
3-clause license, and add $FreeBSD$ to keep the commit script happy.
# This may break some mips stuff, which will be fixed in the next commit.
I/O clock. Thankfully, the simple executive provies a way to querry
the proper clock that works on all models. Move to asking for the SCLK
via this interface.
This gets the serial console working after we start init and open the
console and set the divisor (which turned the output from good to
bad). I can login on the console now.
in the pcb. setjmp/longjmp in the kernel also used these values, so
continue to use them although their use isn't technically the pcb
register array (matching is all that's important for setjmp/longjmp in
the kernel). Finally, eliminate the old register names from regnum.h.
This is a lexical change only. The non-debug .o files have the same md5.
Partially implement generic_bs_*_8() for MIPS platforms.
This is known to work with TARGET_ARCH=mips64 with FreeBSD/BERI.
Assuming that other definitions in cpufunc.h are correct it will
work on non-o64 ABI systems except sibyte. On sibyte and o32 systems
generic_bs_*_8() will remain panic() implementations.
Sponsored by: DARPA, AFRL
Reviewed by: imp, jmallett (older versions)
(Wasting 4k just as a temporary placeholder for a boot environment seems
a bit ridiculous, but hey.)
Tested: gxemul:
$ gxemul -e malta -d i:/home/adrian/work/freebsd/svn/mfsroot-rspro.img -C 4Kc /tftpboot/kernel.MALTA
to unique values.
There's some confusion about what the n32 assembler API really is
(since on page 9 of the spec they say that t0-t3 don't exist, then
turn around on page 22 and say that t4-t7 don't exist), and this
doesn't touch that.
NetBSD's version of this file follows the convention I used here, and
is likely to be correct.
This should fix gdb/ptrace.
sys/arm and sys/mips), squelching the clang 3.3 warnings about this.
Noticed by: tinderbox and many irate spectators
Submitted by: Luiz Otavio O Souza <loos.br@gmail.com>
PR: kern/177759
MFC after: 3 days
Having MIPS_MAX_TLB_ENTRIES defined to 128 is misleading, since it used
to be 64 in older releases of MIPS architecture (where it could be read
from Config1) and can be much more than 128 for the newer processors.
For now, move the definition to the only file using it (mips/mips/tlb.c)
and define MIPS_MAX_TLB_ENTRIES depending on the MIPS cpu defined. Also
add few checks so that we do not write beyond the end of the tlb_state
array.
This fixes a kernel data corruption seen in Netlogic XLP, which was casued
by tlb_save() writing beyond the end of tlb_state array when breaking into
debugger.
Introduce counter(9) API, that implements fast and raceless counters,
provided (but not limited to) for gathering of statistical data.
See http://lists.freebsd.org/pipermail/freebsd-arch/2013-April/014204.html
for more details.
In collaboration with: kib
Reviewed by: luigi
Tested by: ae, ray
Sponsored by: Nginx, Inc.
