Commit Graph

2541 Commits

Author SHA1 Message Date
Justin Hibbits
080286e983 Set EN_MAS7_UPDATE HID0 bit for e500 core.
Without enabling this bit, tlbre and tlbsx don't update the MAS7 register,
resulting in garbage in the register after a read (rather, the previous setting
of it for a tlbwe).  This can result in mmu_booke_mapdev_attr() thinking
mappings that should match actually don't, because tlb1_read_entry() can't
determine the correct address of a given entry.

MFC after:	11-RELEASE
2016-08-07 19:09:56 +00:00
Jason A. Harmening
b57417e56f powerpc busdma: Use pmap_quick_enter_page()/pmap_quick_remove_page() to handle
bouncing of unmapped buffers.  Also treat userspace buffers as unmapped, to
avoid borrowing the UVA for copies.  This allows sync'ing userspace buffers
outside the context of the owning process, and sync'ing bounced maps in
non-sleepable contexts.

This change is equivalent to r286787 for x86.

Reviewed by:	jhibbits
Differential Revision:	https://reviews.freebsd.org/D3989
2016-08-07 15:50:08 +00:00
Justin Hibbits
6cedae09a2 Merge MPC85XX and QorIQ config options
Summary:
MPC85XX and QorIQ are very similar.  When the DPAA dTSEC driver was
added, QORIQ_DPAA was brought in as a config option to support the differences
in hardware register settings between QorIQ (e500mc-, e5500- based) SoCs and
QUICC (e500v1/e500v2-based) SoCs, particularly in the Local Access Window (LAW)
target settings.

Unify these settings using macros to hide details and ease porting, and use a
new function (mpc85xx_is_qoriq()) to distinguish between QorIQ and QUICC SoCs at
runtime.

An alternative to using the function could be to use a variable initialized at
platform attach time, which may incur less overhead at runtime.  Since it's not
in the critical path once booted, this optimization doesn't seem necessary at
first pass.

Reviewed by: nwhitehorn
MFC after:	1 week
Differential Revision: https://reviews.freebsd.org/D7294
2016-08-03 01:22:11 +00:00
Justin Hibbits
d071aa6df2 Use label math instead of hard-coding offsets for return addresses.
Though the chances of the code in these sections changing are low, future-proof
the sections and use label math.

Renumber the surrounding areas to avoid duplicate label numbers.
2016-07-23 02:27:42 +00:00
Justin Hibbits
78cc33fd32 Remove booke_enable_l3_cache declaration and remaining definition.
L3 cache is not defined by Book-E, so is platform specific.  Since it was
already moved for e500-based devices into mpc85xx in r292903, just eliminate it
altogether.  Any device that supports L3 cache should have its own platform
means to enable it.
2016-07-17 19:24:28 +00:00
Justin Hibbits
b926a14ca7 No need to include mpc85xx.h anymore, so remove it. 2016-07-17 19:19:50 +00:00
Nathan Whitehorn
c506e956ba Remove dead code. This should have been removed in r297392, when these
files were moved to dev/ofw, but wasn't, apparently due to some version
control issue.

MFC after:	1 week
2016-07-11 17:02:17 +00:00
Nathan Whitehorn
96c85efb4b Replace a number of conflations of mp_ncpus and mp_maxid with either
mp_maxid or CPU_FOREACH() as appropriate. This fixes a number of places in
the kernel that assumed CPU IDs are dense in [0, mp_ncpus) and would try,
for example, to run tasks on CPUs that did not exist or to allocate too
few buffers on systems with sparse CPU IDs in which there are holes in the
range and mp_maxid > mp_ncpus. Such circumstances generally occur on
systems with SMT, but on which SMT is disabled. This patch restores system
operation at least on POWER8 systems configured in this way.

There are a number of other places in the kernel with potential problems
in these situations, but where sparse CPU IDs are not currently known
to occur, mostly in the ARM machine-dependent code. These will be fixed
in a follow-up commit after the stable/11 branch.

PR:		kern/210106
Reviewed by:	jhb
Approved by:	re (glebius)
2016-07-06 14:09:49 +00:00
Justin Hibbits
91ebf7d765 Remove SoC-specific integrations from dTSEC, to make it SoC agnostic.
This will allow a single kernel to run on all SoCs supported by the dTSEC driver.

Approved by:	re@(gjb)
2016-07-05 06:16:42 +00:00
Justin Hibbits
83d9b89cfb Unbreak the LBC driver, broken with the large RMan and 36-bit physical address changes.
Remove the use of fdt_data_to_res(), and instead construct the resources
manually.  Additionally, avoid the 32-bit size limitation of fdt_data_get(), by
building physical addresses manually from the lbc ranges property.

Approved by:	re@(gjb)
2016-07-05 06:14:23 +00:00
Nathan Whitehorn
f8204502c2 Fix fat-fingering: #if AIM should have been #ifdef AIM to avoid failures on
Book-E kernels.

Approved by:	re (gjb)
Pointy hat to:	nwhitehorn
2016-06-29 16:34:56 +00:00
Nathan Whitehorn
0081393d79 Do not rely on firmware having pre-enabled the MMU in a reasonable way for
late boot: enable it explicitly after installing the page tables. If booting
from an FDT, also make sure to escape the firmware's MMU context early
before overwriting firmware page tables.

Approved by:	re (gjb)
2016-06-29 14:40:43 +00:00
Nathan Whitehorn
d929c32b7f Enter 64-bit mode as early as possible in the 64-bit PowerPC boot sequence.
Most of the effect of setting MSR[SF] is that the CPU will stop ignoring
the high 32 bits of registers containing addresses in load/store
instructions. As such, the kernel was setting it only when it began to
need access to high memory. MSR[SF] also affects the operation of some
conditional instructions, however, and so setting it at late times could
subtly break code at very early times. This fixes use of the FDT mode in
loader, and FDT boot more generally, on 64-bit PowerPC systems.

Hardware provided by: IBM LTC
Approved by: re (kib)
2016-06-26 18:43:42 +00:00
Konstantin Belousov
5c2cf81845 Update comments for the MD functions managing contexts for new
threads, to make it less confusing and using modern kernel terms.

Rename the functions to reflect current use of the functions, instead
of the historic KSE conventions:
  cpu_set_fork_handler -> cpu_fork_kthread_handler (for kthreads)
  cpu_set_upcall -> cpu_copy_thread (for forks)
  cpu_set_upcall_kse -> cpu_set_upcall (for new threads creation)

Reviewed by:	jhb (previous version)
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Approved by:	re (hrs)
Differential revision:	https://reviews.freebsd.org/D6731
2016-06-16 12:05:44 +00:00
Luiz Otavio O Souza
9d6672e13b Fix the deciKelvin to Celsius conversion in kernel.
After r285994, sysctl(8) was fixed to use 273.15 instead of 273.20 as 0C
reference and as result, the temperature read in sysctl(8) now exibits a
+0.1C difference.

This commit fix the kernel references to match the reference value used in
sysctl(8) after r285994.

Sponsored by:	Rubicon Communications (Netgate)
2016-05-22 13:58:32 +00:00
Dmitry Chagin
5437e1d103 Add macro to convert errno and use it when appropriate.
MFC after:	1 week
2016-05-22 12:46:34 +00:00
Oleksandr Tymoshenko
0cc376c134 Use OF_prop_free instead of direct call to free(9)
Reviewed by:	jhibbits
2016-05-14 20:06:38 +00:00
John Baldwin
82cb5c3b5b Native PCI-express HotPlug support.
PCI-express HotPlug support is implemented via bits in the slot
registers of the PCI-express capability of the downstream port along
with an interrupt that triggers when bits in the slot status register
change.

This is implemented for FreeBSD by adding HotPlug support to the
PCI-PCI bridge driver which attaches to the virtual PCI-PCI bridges
representing downstream ports on HotPlug slots. The PCI-PCI bridge
driver registers an interrupt handler to receive HotPlug events. It
also uses the slot registers to determine the current HotPlug state
and drive an internal HotPlug state machine. For simplicty of
implementation, the PCI-PCI bridge device detaches and deletes the
child PCI device when a card is removed from a slot and creates and
attaches a PCI child device when a card is inserted into the slot.

The PCI-PCI bridge driver provides a bus_child_present which claims
that child devices are present on HotPlug-capable slots only when a
card is inserted. Rather than requiring a timeout in the RC for
config accesses to not-present children, the pcib_read/write_config
methods fail all requests when a card is not present (or not yet
ready).

These changes include support for various optional HotPlug
capabilities such as a power controller, mechanical latch,
electro-mechanical interlock, indicators, and an attention button.
It also includes support for devices which require waiting for
command completion events before initiating a subsequent HotPlug
command. However, it has only been tested on ExpressCard systems
which support surprise removal and have none of these optional
capabilities.

PCI-express HotPlug support is conditional on the PCI_HP option
which is enabled by default on arm64, x86, and powerpc.

Reviewed by:	adrian, imp, vangyzen (older versions)
Relnotes:	yes
Differential Revision:	https://reviews.freebsd.org/D6136
2016-05-05 22:26:23 +00:00
Pedro F. Giffuni
20d7fee404 powerpc: Replace rounddown() from r298856 with roundup().
Both are equivalent but roundup is more logical for this case.
Catch another case while here.

Pointed out by:	jhibbits
2016-04-30 19:50:59 +00:00
Pedro F. Giffuni
a1118f872e powerpc: Make use of our rounddown() macro when sys/param.h is available.
No functional change.
2016-04-30 18:56:35 +00:00
John Baldwin
e131ba36e8 Move 'device pci' for the PCI bus driver to the MI NOTES file.
The PCI bus was already listed in all of the MD NOTES files and the
driver should at least compile on all platforms.
2016-04-29 23:53:55 +00:00
John Baldwin
9f7f2d8f89 Remove vestiges of IEEE-488/GPIB drivers removed in r276214. 2016-04-29 22:29:33 +00:00
John Baldwin
e240255ffc Add a bus_null_rescan() method that always fails with an error.
Use this in place of kobj_error_method to disable BUS_RESCAN() on
PCI drivers that do not use the "standard" scanning algorithm.
2016-04-27 17:49:42 +00:00
John Baldwin
67e7d085ae Add a pcib_attach_child() method to manage adding the child "pci" device.
This allows the PCI-PCI bridge driver to save a reference to the child
device in its softc.

Note that this required moving the "pci" device creation out of
acpi_pcib_attach().  Instead, acpi_pcib_attach() is renamed to
acpi_pcib_fetch_prt() as it's sole action now is to fetch the PCI
interrupt routing table.

Differential Revision:	https://reviews.freebsd.org/D6021
2016-04-27 16:39:05 +00:00
John Baldwin
3d0338a092 Implement a PCI bus rescan method.
Rescanning a PCI bus uses the following steps:
- Fetch the current set of child devices and save it in the 'devlist'
  array.
- Allocate a parallel array 'unchanged' initalized with NULL pointers.
- Scan the bus checking each slot (and each function on slots with a
  multifunction device).
- If a valid function is found, look for a matching device in the 'devlist'
  array.  If a device is found, save the pointer in the 'unchanged' array.
  If a device is not found, add a new device.
- After the scan has finished, walk the 'devlist' array deleting any
  devices that do not have a matching pointer in the 'unchanged' array.
- Finally, fetch an updated set of child devices and explicitly attach any
  devices that are not present in the 'unchanged' array.

This builds on the previous changes to move subclass data management into
pci_alloc_devinfo(), pci_child_added(), and bus_child_deleted().

Subclasses of the PCI bus use custom rescan logic explicitly override the
rescan method to disable rescans.

Differential Revision:	https://reviews.freebsd.org/D6018
2016-04-27 16:31:12 +00:00
Pedro F. Giffuni
910c079886 sys/powerpc: make use of the howmany() macro when available.
We have a howmany() macro in the <sys/param.h> header that is
convenient to re-use as it makes things easier to read.
2016-04-26 14:44:49 +00:00
Justin Hibbits
01a40173f7 OR in the unsigned form of the MCAR lower register.
When ORing in a register_t to a wider integer (vm_paddr_t), it gets sign
extended, so high addresses overwrite the upper word with all 0xf.  Cast to the
unsigned form (u_register_t), to avoid this problem, and get correct addresses
printed.
2016-04-25 03:01:57 +00:00
Justin Hibbits
da3aa7a13f Init static compiled-in env when no metadata present.
With this, a static environment can be compiled in via config(5).  This allows,
among other things, the use of a compiled-in debug console (hw.uart.dbgport) for
kgdb.
2016-04-25 00:55:51 +00:00
Pedro F. Giffuni
d9c9c81c08 sys: use our roundup2/rounddown2() macros when param.h is available.
rounddown2 tends to produce longer lines than the original code
and when the code has a high indentation level it was not really
advantageous to do the replacement.

This tries to strike a balance between readability using the macros
and flexibility of having the expressions, so not everything is
converted.
2016-04-21 19:57:40 +00:00
Pedro F. Giffuni
33495e5daf Use our nitems() macro when param.h is available.
Replacements specific to arm, mips, pc98, powerpc and sparc64.

Discussed in:	freebsd-current
2016-04-20 15:45:55 +00:00
Justin Hibbits
f60708c9f7 Fix SMP booting for PowerPC Book-E
Summary:
PowerPC Book-E SMP is currently broken for unknown reasons.  Pull in
Semihalf changes made c2012 for e500mc/e5500, which enables booting SMP.

This eliminates the shared software TLB1 table, replacing it with
tlb1_read_entry() function.

This does not yet support ePAPR SMP booting, and doesn't handle resetting CPUs
already released (ePAPR boot releases APs to a spin loop waiting on a specific
address).  This will be addressed in the near future by using the MPIC to reset
the AP into our own alternate boot address.

This does include a change to the dpaa/dtsec(4) driver, to mark the portals as
CPU-private.

Test Plan:
Tested on Amiga X5000/20 (P5020).  Boots, prints the following
messages:

 Adding CPU 0, pir=0, awake=1
 Waking up CPU 1 (dev=1)
 Adding CPU 1, pir=20, awake=1
 SMP: AP CPU #1 launched

top(1) shows CPU1 active.

Obtained from:	Semihalf
Relnotes:	Yes
Differential Revision: https://reviews.freebsd.org/D5945
2016-04-19 01:48:18 +00:00
Pedro F. Giffuni
26f0e234f7 powerpc: for pointers replace 0 with NULL.
These are mostly cosmetical, no functional change.

Found with devel/coccinelle.

Reviewed by:	jhibbits
2016-04-15 14:25:13 +00:00
John Baldwin
6cd99ae86d Add a new PCI bus interface method to alloc the ivars (dinfo) for a device.
The ACPI and OFW PCI bus drivers as well as CardBus override this to
allocate the larger ivars to hold additional info beyond the stock PCI ivars.

This removes the need to pass the size to functions like pci_add_iov_child()
and pci_read_device() simplifying IOV and bus rescanning implementations.

As a result of this and earlier changes, the ACPI PCI bus driver no longer
needs its own device_attach and pci_create_iov_child methods but can use
the methods in the stock PCI bus driver instead.

Differential Revision:	https://reviews.freebsd.org/D5891
2016-04-15 03:42:12 +00:00
Pedro F. Giffuni
74b8d63dcc Cleanup unnecessary semicolons from the kernel.
Found with devel/coccinelle.
2016-04-10 23:07:00 +00:00
Justin Hibbits
f00e990465 VM_MAXUSER_ADDRESS is highest page start, not highest address.
In case a single page mapping is requested first, which might overlap the user
address space, fix the device map block to the next page.
2016-04-10 15:50:45 +00:00
Justin Hibbits
f2c3b7f2ba Restructure device mappings for Book-E.
Summary:
There is currently a 1GB hole between user and kernel address spaces
into which direct (1:1 PA:VA) device mappings go.  This appears to go largely
unused, leaving all devices to contend with the 128MB block at the end of the
32-bit space (0xf8000000-0xffffffff).  This easily fills up, and needs to be
densely packed.  However, dense packing wastes precious TLB1 space, of which
there are only 16 (e500v2) or 64(e5500) entries available.

Change this by using the 1GB space for all device mappings, and allow the kernel
to use the entire upper 1GB for KVA.  This also allows us to use sparse device
mappings, freeing up TLB entries.

Test Plan: Boot tested on p5020.

Differential Revision: https://reviews.freebsd.org/D5832
2016-04-10 15:48:09 +00:00
John Baldwin
496dfa89a6 Convert pci_delete_child() to a bus_child_deleted() method.
Instead of providing a wrapper around device_delete_child() that the PCI
bus and child bus drivers must call explicitly, move the bulk of the logic
from pci_delete_child() into a bus_child_deleted() method
(pci_child_deleted()).  This allows PCI devices to be safely deleted via
device_delete_child().
- Add a bus_child_deleted method to the ACPI PCI bus which clears the
  device_t associated with the corresponding ACPI handle in addition to
  the normal PCI bus cleanup.
- Change cardbus_detach_card to call device_delete_children() and move
  CardBus-specific delete logic into a new cardbus_child_deleted() method.
- Use device_delete_child() instead of pci_delete_child() in the SRIOV code.
- Add a bus_child_deleted method to the OpenFirmware PCI bus drivers which
  frees the OpenFirmware device info for each PCI device.

Reviewed by:	imp
Tested on:	amd64 (CardBus and PCI-e hotplug)
Differential Revision:	https://reviews.freebsd.org/D5831
2016-04-06 04:10:22 +00:00
Justin Hibbits
2db664d7b5 Make i2c device child auto-probe work for MPC85xx and QorIQ SoCs.
OFW i2c probing requires a new method ofw_bus_get_node(), and the bus device is
assumed iichb.  With these changes, i2c devices attached in fdt are probed and
attached automagically.
2016-04-05 02:27:01 +00:00
Zbigniew Bodek
c43a86743c Reduce OFW PCI code duplication - involves ARM, PPC and SPARC64
Import portions of the PowerPC OF PCI implementation into new file
"ofwpci.c", common for other platforms. The files ofw_pci.c and ofw_pci.h
from sys/powerpc/ofw no longer exist. All required declarations are moved
to sys/dev/ofw/ofwpci.h. This creates a new ofw_pci_write_ivar() function
and modifies some others methods. Most functions contain existing ppc
implementations in the majority unchanged. Now there is no need to have
multiple identical copies of methods for various architectures.

Requested by:  jhibbits
Reviewed by:   jhibbits, marius
Submitted by:  Marcin Mazurek <mma@semihalf.com>
Obtained from: Semihalf
Sponsored by:  Annapurna Labs
Differential Revision: https://reviews.freebsd.org/D4879
2016-03-29 15:19:56 +00:00
Justin Hibbits
f8fd3fb518 Fix the resource_list_print_type() calls to use uintmax_t.
Missed a bunch from r297000.
2016-03-22 22:25:08 +00:00
Ian Lepore
dec4873723 Fix fallout from r292180 (Dec 2015)... ensure that every driver which has
a DRIVER_MODULE() referencing mmc_driver has a MODULE_DEPEND() on mmc.  This
is because the kernel linker only searches for symbols in dependent modules,
so loading sdhci_pci (and other bus-flavors of sdhci) would fail when mmc
was not compiled into the kernel (even if you hand-loaded mmc first).

(Thanks to jilles@ for providing the vital clue about the kernel linker.)
2016-03-21 00:52:24 +00:00
Justin Hibbits
1c81bc8303 Increase booke bus max address to 36-bits.
Sponsored by:	Alex Perez/Inertial Computing
2016-03-18 01:30:58 +00:00
Justin Hibbits
da1b038af9 Use uintmax_t (typedef'd to rman_res_t type) for rman ranges.
On some architectures, u_long isn't large enough for resource definitions.
Particularly, powerpc and arm allow 36-bit (or larger) physical addresses, but
type `long' is only 32-bit.  This extends rman's resources to uintmax_t.  With
this change, any resource can feasibly be placed anywhere in physical memory
(within the constraints of the driver).

Why uintmax_t and not something machine dependent, or uint64_t?  Though it's
possible for uintmax_t to grow, it's highly unlikely it will become 128-bit on
32-bit architectures.  64-bit architectures should have plenty of RAM to absorb
the increase on resource sizes if and when this occurs, and the number of
resources on memory-constrained systems should be sufficiently small as to not
pose a drastic overhead.  That being said, uintmax_t was chosen for source
clarity.  If it's specified as uint64_t, all printf()-like calls would either
need casts to uintmax_t, or be littered with PRI*64 macros.  Casts to uintmax_t
aren't horrible, but it would also bake into the API for
resource_list_print_type() either a hidden assumption that entries get cast to
uintmax_t for printing, or these calls would need the PRI*64 macros.  Since
source code is meant to be read more often than written, I chose the clearest
path of simply using uintmax_t.

Tested on a PowerPC p5020-based board, which places all device resources in
0xfxxxxxxxx, and has 8GB RAM.
Regression tested on qemu-system-i386
Regression tested on qemu-system-mips (malta profile)

Tested PAE and devinfo on virtualbox (live CD)

Special thanks to bz for his testing on ARM.

Reviewed By: bz, jhb (previous)
Relnotes:	Yes
Sponsored by:	Alex Perez/Inertial Computing
Differential Revision: https://reviews.freebsd.org/D4544
2016-03-18 01:28:41 +00:00
Bjoern A. Zeeb
61fc4ac3aa Only check for SYS_freebsd6_lseek if the syscall code is defined.
Whether this is the right or best solution is unclear but it fixes the
build for now.
2016-03-14 14:55:15 +00:00
Justin Hibbits
11fd20b526 Let rman_init() initialize the default rman range.
If rm_start and rm_end are both 0 on input to rman_init(), rman_init()
pre-initializes them to the default range.  No need to set it before.
2016-03-03 01:12:13 +00:00
Justin Hibbits
8bc8506e91 Fix 2 bugs in the mpc85xx local bus controller driver.
1) Include opt_platform.h to get QORIQ_DPAA.  Otherwise the definition of
OCP85XX_TGTIF_LBC is incorrect.
2) The child resources are already allocated, just activate them, instead of
incorrectly remapping the memory regions (resource lists for lbc consist of the
virtual address of the child's resources, not the physical address).

Sponsored by:	Alex Perez/Inertial Computing
2016-03-02 00:18:05 +00:00
Justin Hibbits
a49d0aa92a Add another compatibility check for QorIQ GPIO driver.
Some MPC85xx GPIO controllers are compatible with QorIQ.

It may make more sense in the future to rename this and mpc85xx_gpio.c, as
mpc85xx_gpio.c appears to only be compatible with a few mpc85xx SoCs.  All other
MPC85xx SoCs use the same controller as QorIQ.
2016-03-01 03:41:48 +00:00
Justin Hibbits
54ac2713d5 Add VM_MEMATTR_CACHEABLE support for AIM, for parity with Book-E.
Not used right now, but may be in the future anyway.
2016-03-01 00:50:39 +00:00
Justin Hibbits
0aeed3e993 Add support for the Freescale dTSEC DPAA-based ethernet controller.
Freescale's QorIQ line includes a new ethernet controller, based on their
Datapath Acceleration Architecture (DPAA).  This uses a combination of a Frame
manager, Buffer manager, and Queue manager to improve performance across all
interfaces by being able to pass data directly between hardware acceleration
interfaces.

As part of this import, Freescale's Netcomm Software (ncsw) driver is imported.
This was an attempt by Freescale to create an OS-agnostic sub-driver for
managing the hardware, using shims to interface to the OS-specific APIs.  This
work was abandoned, and Freescale's primary work is in the Linux driver (dual
BSD/GPL license).  Hence, this was imported directly to sys/contrib, rather than
going through the vendor area.  Going forward, FreeBSD-specific changes may be
made to the ncsw code, diverging from the upstream in potentially incompatible
ways.  An alternative could be to import the Linux driver itself, using the
linuxKPI layer, as that would maintain parity with the vendor-maintained driver.
However, the Linux driver has not been evaluated for reliability yet, and may
have issues with the import, whereas the ncsw-based driver in this commit was
completed by Semihalf 4 years ago, and is very stable.

Other SoC modules based on DPAA, which could be added in the future:
* Security and Encryption engine (SEC4.x, SEC5.x)
* RAID engine

Additional work to be done:
* Implement polling mode
* Test vlan support
* Add support for the Pattern Matching Engine, which can do regular expression
  matching on packets.

This driver has been tested on the P5020 QorIQ SoC.  Others listed in the
dtsec(4) manual page are expected to work as the same DPAA engine is included in
all.

Obtained from:	Semihalf
Relnotes:	Yes
Sponsored by:	Alex Perez/Inertial Computing
2016-02-29 03:38:00 +00:00
Justin Hibbits
0f7aeab0e7 Implement pmap_change_attr() for PowerPC (Book-E only for now)
Summary:
Some drivers need special memory requirements.  X86 solves this with a
pmap_change_attr() API, which DRM uses for changing the mapping of the GART and
other memory regions.  Implement the same function for PowerPC.  AIM currently
does not need this, but will in the future for DRM, so a default is added for
that, for business as usual.  Book-E has some drivers coming down that do
require non-default memory coherency.  In this case, the Datapath Acceleration
Architecture (DPAA) based ethernet controller has 2 regions for the buffer
portals: cache-inhibited, and cache-enabled.  By default, device memory is
cache-inhibited.  If the cache-enabled memory regions are mapped
cache-inhibited, an alignment exception is thrown on access.

Test Plan:
Tested with a new driver to be added after this (DPAA dTSEC ethernet driver).
No alignment exceptions thrown, driver works as expected with this.

Reviewed By:	nwhitehorn
Sponsored by:	Alex Perez/Inertial Computing
Differential Revision: https://reviews.freebsd.org/D5471
2016-02-27 20:39:36 +00:00