to match the new state of affairs. The hardware we support has always been
able to do unaligned accesses, we've just never enabled it until now.
This brings FreeBSD into line with all the other major OSes, and should help
with the growing volume of 3rd-party software that assumes unaligned access
will just work on armv6 and armv7.
have ACLE support built in. The ACLE (ARM C Language Extensions) defines
a set of standardized symbols which indicate the architecture version and
features available. ACLE support is built in to modern compilers (both
clang and gcc), but absent from gcc prior to 4.4.
ARM (the company) provides the acle-compat.h header file to define the
right symbols for older versions of gcc. Basically, acle-compat.h does
for arm about the same thing cdefs.h does for freebsd: defines
standardized macros that work no matter which compiler you use. If ARM
hadn't provided this file we would have ended up with a big #ifdef __arm__
section in cdefs.h with our own compatibility shims.
Remove #include <machine/acle-compat.h> from the zillion other places (an
ever-growing list) that it appears. Since style(9) requires sys/types.h
or sys/param.h early in the include list, and both of those lead to
including cdefs.h, only a couple special cases still need to include
acle-compat.h directly.
Loves it: imp
where possible. In the places that doesn't work (multi-line inline asm,
and places where the old armv4 cpufuncs mechanism is used), annotate the
accesses with a comment that includes SCTLR. Now a grep -i sctlr can find
all the system control register manipulations.
No functional changes.
compilers can emit arm instructions that require 8-byte alignment. The
alignment-sensitive instructions were added in armv5, which has to be
supported by our combined v4/v5 kernels, so the value is set uncoditionally
for all arm architecture versions.
Also adjust the comment to explain in more detail why the macros have the
form and values they do.
Per advice from bde@, maintain the unsignedness of the value of _ALIGNBYTES
(but do so using his second choice of allowing sizeof() to supply the
unsignedness, rather than just hardcoding '8U', which in my mind would
require an even more verbose comment to explain why it's right). Also
explain in the comment that the resulting type of _ALIGN() is equivelent
to uinptr_t on arm (32-bit unsigned int), but it's purposely spelled as
"unsigned" to avoid problems with including other header files. Even
including machine/_types.h to allow use of __uintptr_t causes compilation
failures because of this header being included (indirectly) in asm code.
The discussion that led to this change (albeit at a glacial pace) is at
https://lists.freebsd.org/pipermail/svn-src-head/2014-November/064593.html
implementations. Early in the boot the kernel will use an approximate,
however after the timer has been probed it will switch to a more accurate
implementation.
Reviewed by: manu
Sponsored by: ABT Systems Ltd
Differential Revision: https://reviews.freebsd.org/D5762
and R/W emulation aborts under pmap lock.
There were two reasons for using of atomic operations:
(1) the pmap code is based on i386 one where they are used,
(2) there was an idea that access and R/W emulation aborts should be
handled as quick as possible, without pmap locking.
However, the atomic operations in i386 pmap code are used only because
page table entries may be modified by hardware. At the beginning, we
were not sure that it's the only reason. So even if arm hardware does
not modify them, we did not risk to not use them at that time. Further,
it turns out after some testing that using of pmap lock for access and
R/W emulation aborts does not bring any extra cost and there was no
measurable difference. Thus, we have decided finally to use pmap lock
for all operations on page table entries and so, there is no reason for
atomic operations on them. This makes the code cleaner and safer.
This decision introduce a question if it's safe to use pmap lock for
access and R/W emulation aborts. Anyhow, there may happen two cases in
general:
(A) Aborts while the pmap lock is locked already - this should not
happen as pmap lock is not recursive. However, under pmap lock only
internal kernel data should be accessed and such data should be mapped
with A bit set and NM bit cleared. If double abort happens, then
a mapping of data which has caused it must be fixed.
(B) Aborts while another lock(s) is/are locked - this already can
happen. There is no difference here if it's either access or R/W
emulation abort, or if it's some other abort.
Reviewed by: kib
(PL1) and unprivileged (PL0) read/write access. As cp15 virtual to
physical address translation operations are used, interrupts must be
disabled to get consistent result when they are called.
These functions should be used only in very specific occasions like
during abort handling or kernel debugging. One of them is going to be
used in pmap_fault(). However, complete function set is added. It cost
nothing, as they are inlined.
While here, fix comment of #endif.
Reviewed by: kib
universal.
(1) New struct intr_map_data is defined as a container for arbitrary
description of an interrupt used by a device. Typically, an interrupt
number and configuration relevant to an interrupt controller is encoded
in such description. However, any additional information may be encoded
too like a set of cpus on which an interrupt should be enabled or vendor
specific data needed for setup of an interrupt in controller. The struct
intr_map_data itself is meant to be opaque for INTRNG.
(2) An intr_map_irq() function is created which takes an interrupt
controller identification and struct intr_map_data as arguments and
returns global interrupt number which identifies an interrupt.
(3) A set of functions to be used by bus drivers is created as well as
a corresponding set of methods for interrupt controller drivers. These
sets take both struct resource and struct intr_map_data as one of the
arguments. There is a goal to keep struct intr_map_data in struct
resource, however, this way a final solution is not limited to that.
(4) Other small changes are done to reflect new situation.
This is only first step aiming to create stable interface for interrupt
controller drivers. Thus, some temporary solution is taken. Interrupt
descriptions for devices are stored in INTRNG and two specific mapping
function are created to be temporary used by bus drivers. That's why
the struct intr_map_data is not opaque for INTRNG now. This temporary
solution will be replaced by final one in next step.
Differential Revision: https://reviews.freebsd.org/D5730
- Don't convert atags address passed from U-Boot. It's real physical
address (and we have 1:1 mapping).
- Size of tags is encoded in words, not in bytes
This allow us to boot FreeBSD kernel (using uImage encapsulation) directly
from U-boot using 'bootm' command or by Android fastboot loader.
For now, kernel uImage must be marked as Linux, but we can add support for
FreeBSD into U-Boot later.
controller IPI provider.
New struct intr_ipi is defined which keeps all info about an IPI:
its name, counter, send and dispatch methods. Generic intr_ipi_setup(),
intr_ipi_send() and intr_ipi_dispatch() functions are implemented.
An IPI provider must implement two functions:
(1) an intr_ipi_send_t function which is able to send an IPI,
(2) a setup function which initializes itself for an IPI and
calls intr_ipi_setup() with appropriate arguments.
Differential Revision: https://reviews.freebsd.org/D5700
the interrupt framework is also going to be used by another (MIPS)
architecture. IPI implementations may vary much across different
architectures.
An IPI implementation should still define INTR_IPI_COUNT and use
intr_ipi_setup_counters() to setup IPI counters which are inside of
intrcnt[] and intrnames[] arrays. Those are used for sysctl and ddb.
Then, intr_ipi_increment_count() should be used to increment obtained
counter.
Reviewed by: imp
Differential Revision: https://reviews.freebsd.org/D5459
intr_pic_init_secondary. Replace them with a direct call. On BCM2836
and ARMADA XP we need to add this function, but it can be empty.
Reviewed by: ian, imp
Sponsored by: ABT Systems Ltd
Differential Revision: https://reviews.freebsd.org/D5460
slightly wrong on the others. We should just check if mp_ncpus is set to
more than one CPU as we may wish to run on a single core even when SMP is
available.
Reviewed by: ian
Sponsored by: ABT Systems Ltd
Differential Revision: https://reviews.freebsd.org/D5458
or pte-v6.h in files which needs it.
There are quite internal definitions in pte-v4.h and pte-v6.h headers
specific for corresponding pmap implementation. These headers should be
included only in very few files and an intention is to not hide for
which implementation such files are.
Further, sys/arm/arm/elf_trampoline.c is an example of file which
uses armv4 like pmap implementation for both armv4 and armv6 platforms.
This is another reason why pte.h which includes specific header
according to __ARM_ARCH is not created.
Create new pmap.h which includes specific header according to
__ARM_ARCH.
Note that <machine/pmap.h> is included from <vm/pmap.h> so one common
<machine/pmap.h> must exist.
are not utilized there. Only domain #0 is used and there is no reference
to it in the whole pmap-v6.c. Thus initialize domain access register in
locore-v6.c without reference too.
It turned out that devmap.c is not only file in which PTE_DEVICE
is used and simultaneously, built for both armv4 and armv6 platforms.
When I tried to build all arm kernels before r295168 commit, it was
hid by some other local changes in my tree. I hope that this is just
temporary workaround before VM_MEMATTR_DEVICE could be used instead of
PTE_DEVICE outside of pmap code for __ARM_ARCH < 6.
instead of hiding behind pmap_map_chunk(). It's not longer needed
after old pmap-v6 code was removed.
For compatibility with __ARM_ARCH < 6, define PTE_DEVICE in devmap.c
file. Certainly, it would be nice if VM_MEMATTR_DEVICE could be used
even for __ARM_ARCH < 6.
do not depend on pmap internals. This is a preparation for hiding
internal pmap definitions as much as possible from the rest of system.
Simultaneously, the protection argument evaluation is fixed. Happily,
it did not effect the mappings. And it's the reason why it was not fixed
earlier.
