If a kobj method doesn't have any explicitly provided default
implementation, then it is auto-assigned kobj_error_method.
kobj_error_method is proper only for methods that return error code,
because it just returns ENXIO.
So, in the case of unimplemented bus_add_child caller would get
(device_t)ENXIO as a return value, which would cause the mistake to go
unnoticed, because return value is typically checked for NULL.
Thus, a specialized null_add_child is added. It would have sufficied
for correctness to return NULL, but this type of mistake was deemed to
be rare and serious enough to call panic instead.
Watch out for this kind of problem with other kobj methods.
Suggested by: jhb, imp
MFC after: 2 weeks
This reflects actual type used to store and compare child device orders.
Change is mostly done via a Coccinelle (soon to be devel/coccinelle)
semantic patch.
Verified by LINT+modules kernel builds.
Followup to: r212213
MFC after: 10 days
handlers. This is primarily intended as a way to allow devices that use
multiple interrupts (e.g. MSI) to meaningfully distinguish the various
interrupt handlers.
- Add a new BUS_DESCRIBE_INTR() method to the bus interface to associate
a description with an active interrupt handler setup by BUS_SETUP_INTR.
It has a default method (bus_generic_describe_intr()) which simply passes
the request up to the parent device.
- Add a bus_describe_intr() wrapper around BUS_DESCRIBE_INTR() that supports
printf(9) style formatting using var args.
- Reserve MAXCOMLEN bytes in the intr_handler structure to hold the name of
an interrupt handler and copy the name passed to intr_event_add_handler()
into that buffer instead of just saving the pointer to the name.
- Add a new intr_event_describe_handler() which appends a description string
to an interrupt handler's name.
- Implement support for interrupt descriptions on amd64 and i386 by having
the nexus(4) driver supply a custom bus_describe_intr method that invokes
a new intr_describe() MD routine which in turn looks up the associated
interrupt event and invokes intr_event_describe_handler().
Requested by: many
Reviewed by: scottl
MFC after: 2 weeks
probe. The current device order is unchanged. This commit just adds the
infrastructure and ABI changes so that it is easier to merge later changes
into 8.x.
- Driver attachments now have an associated pass level. Attachments are
not allowed to probe or attach to drivers until the system-wide pass level
is >= the attachment's pass level. By default driver attachments use the
"last" pass level (BUS_PASS_DEFAULT). Driver's that wish to probe during
an earlier pass use EARLY_DRIVER_MODULE() instead of DRIVER_MODULE() which
accepts the pass level as an additional parameter.
- A new method BUS_NEW_PASS has been added to the bus interface. This
method is invoked when the system-wide pass level is changed to kick off
a rescan of the device tree so that drivers that have just been made
"eligible" can probe and attach.
- The bus_generic_new_pass() function provides a default implementation of
BUS_NEW_PASS(). It first allows drivers that were just made eligible for
this pass to identify new child devices. Then it propogates the rescan to
child devices that already have an attached driver by invoking their
BUS_NEW_PASS() method. It also reprobes devices without a driver.
- BUS_PROBE_NOMATCH() is only invoked for devices that do not have
an attached driver after being scanned during the final pass.
- The bus_set_pass() function is used during boot to raise the pass level.
Currently it is only called once during root_bus_configure() to raise
the pass level to BUS_PASS_DEFAULT. This has the effect of probing all
devices in a single pass identical to previous behavior.
Reviewed by: imp
Approved by: re (kib)
- An "at" hint now reserves a device name.
- A new BUS_HINT_DEVICE_UNIT method is added to the bus interface. When
determining the unit number of a device, this method is invoked to
let the bus driver specify the unit of a device given a specific
devclass. This is the only way a device can be given a name reserved
via an "at" hint.
- Implement BUS_HINT_DEVICE_UNIT() for the acpi(4) and isa(4) bus drivers.
Both of these busses implement this by comparing the resources for a
given hint device with the resources enumerated by ACPI/PnPBIOS and
wire a unit if the hint resources are a subset of the "real" resources.
- Use bus_hinted_children() for adding hinted devices on isa(4) busses
now instead of doing it by hand.
- Remove the unit kludging from sio(4) as it is no longer necessary.
Prodding from: peter, imp
OK'd by: marcel
MFC after: 1 month
resource to a CPU. The default method is to pass the request up to the
parent similar to BUS_CONFIG_INTR() so that all busses don't have to
explicitly implement bus_bind_intr. A bus_bind_intr(9) wrapper routine
similar to bus_setup/teardown_intr() is added for device drivers to use.
Unbinding an interrupt is done by binding it to NOCPU. The IRQ resource
must be allocated, but it can happen in any order with respect to
bus_setup_intr(). Currently it is only supported on amd64 and i386 via
nexus(4) methods that simply call the intr_bind() routine.
Tested by: gallatin
Instead, we want busses to explicitly specify an add_child routine if they
want to support identify routines, but by default disallow having outside
drivers add devices.
- Give smbus(4) an explicit bus_add_child() method.
Requested by: imp
device_add_child_ordered(). Previously, a device driver that wanted to
add a new child device in its identify routine had to know if the parent
driver had a custom bus_add_child method and use BUS_ADD_CHILD() in that
case, otherwise use device_add_child(). Getting it wrong in either
direction would result in panics or failure to add the child device. Now,
BUS_ADD_CHILD() always works isolating child drivers from having to know
intimate details about the parent driver.
Discussed with: imp
MFC after: 1 week
required by arches like sparc64 (not yet implemented) and sun4v where there
are seperate IOMMU's for each PCI bus... For all other arches, it will
end up returning NULL, which makes it a no-op...
Convert a few drivers (the ones we've been working w/ on sun4v) to the
new convection... Eventually all drivers will need to replace the parent
tag of NULL, w/ bus_get_dma_tag(dev), though dev is usually different for
each driver, and will require hand inspection...
Reviewed by: scottl (earlier version)
to use the hinted child system. Bus drivers that use this need to
implmenet the bus_hinted_child method, where they actually add the
child to their bus, as they see fit. The bus is repsonsible for
getting the attribtues for the child, adding it in the right order,
etc. ISA hinting will be updated to use this method.
MFC After: 3 days
about interrupt trigger mode and interrupt polarity. This allows ACPI
for example to pass interrupt resource information up the hierarchy.
The default implementation of the method therefore is to pass the
request to the parent.
Reviewed by: jhb, njl
Alter consumers of this method to conform to the new convention.
Minor cosmetic adjustments to bus.h.
This isn't of concern as this interface isn't in use yet.
implementation.
Add bus_generic_rl_{get,set,delete,release,alloc}_resource() functions
which provide generic operations for devices using resource list style
resource management.
This should simplify a number of bus drivers. Further commits to follow.
non-device code.
* Re-implement the method dispatch to improve efficiency. The new system
takes about 40ns for a method dispatch on a 300Mhz PII which is only
10ns slower than a direct function call on the same hardware.
This changes the new-bus ABI slightly so make sure you re-compile any
driver modules which you use.
resource_list_release. This removes the dependancy on the
layout of ivars.
* Move set_resource, get_resource and delete_resource from
isa_if.m to bus_if.m.
* Simplify driver code by providing wrappers to those methods:
bus_set_resource(dev, type, rid, start, count);
bus_get_resource(dev, type, rid, startp, countp);
bus_get_resource_start(dev, type, rid);
bus_get_resource_count(dev, type, rid);
bus_delete_resource(dev, type, rid);
* Delete isa_get_rsrc and use bus_get_resource_start instead.
* Fix a stupid typo in isa_alloc_resource reported by Takahashi
Yoshihiro <nyan@FreeBSD.org>.
* Print a diagnostic message if we can't assign resources to a PnP
device.
* Change device_print_prettyname() so that it doesn't print
"(no driver assigned)-1" for anonymous devices.
add nodes to the tree. Also, default to bus_generic_driver_added for
the BUS_DRIVER_ADDED method.
This allows newbus busses to be kldload'd.
Reviewed by: dfr
- device_print_child() either lets the BUS_PRINT_CHILD
method produce the entire device announcement message or
it prints "foo0: not found\n"
Alter sys/kern/subr_bus.c:bus_generic_print_child() to take on
the previous behavior of device_print_child() (printing the
"foo0: <FooDevice 1.1>" bit of the announce message.)
Provide bus_print_child_header() and bus_print_child_footer()
to actually print the output for bus_generic_print_child().
These functions should be used whenever possible (unless you can
just use bus_generic_print_child())
The BUS_PRINT_CHILD method now returns int instead of void.
Modify everything else that defines or uses a BUS_PRINT_CHILD
method to comply with the above changes.
- Devices are 'on' a bus, not 'at' it.
- If a custom BUS_PRINT_CHILD method does the same thing
as bus_generic_print_child(), use bus_generic_print_child()
- Use device_get_nameunit() instead of both
device_get_name() and device_get_unit()
- All BUS_PRINT_CHILD methods return the number of
characters output.
Reviewed by: dfr, peter
easier to use and more flexible.
* Change BUS_ADD_CHILD to take an order argument instead of a place.
* Define a partial ordering for isa devices so that sensitive devices are
probed before non-sensitive ones.
instances to a parent bus.
* Define a new method BUS_ADD_CHILD which can be called from DEVICE_IDENTIFY
to add new instances.
* Add a generic implementation of DEVICE_PROBE which calls DEVICE_IDENTIFY
for each driver attached to the parent's devclass.
* Move the hint-based isa probe from the isa driver to a new isahint driver
which can be shared between i386 and alpha.
through' to the C compiler.
* Allow the interface to specify a default implementation for methods.
* Allow 'static' methods which are not device specific.
* Add a simple scheme for probe routines to return a priority value. To
make life simple, priority values are negative numbers (positive numbers
are standard errno codes) with zero being the highest priority. The
driver which returns the highest priority will be chosen for the device.
i386 platform boots, it is no longer ISA-centric, and is fully dynamic.
Most old drivers compile and run without modification via 'compatability
shims' to enable a smoother transition. eisa, isapnp and pccard* are
not yet using the new resource manager. Once fully converted, all drivers
will be loadable, including PCI and ISA.
(Some other changes appear to have snuck in, including a port of Soren's
ATA driver to the Alpha. Soren, back this out if you need to.)
This is a checkpoint of work-in-progress, but is quite functional.
The bulk of the work was done over the last few years by Doug Rabson and
Garrett Wollman.
Approved by: core
* bus_setup_intr() as a wrapper for BUS_SETUP_INTR
* bus_teardown_intr() as a wrapper for BUS_TEARDOWN_INTR
* device_get_nameunit() which returns e.g. "foo0" for name "foo" and unit 0.
* device_set_desc_copy() malloc a copy of the description string.
* device_quiet(), device_is_quiet(), device_verbose() suppress probe message.
Add one method to the BUS interface, BUS_CHILD_DETACHED() which is called
after the child has been detached to allow the bus to clean up any memory
which it allocated on behalf of the child.
I also fixed a bug which corrupted the list of drivers in a devclass if
a driver was added to more than one devclass.
- Interface wth the new resource manager.
- Allow for multiple drivers implementing a single devclass.
- Remove ordering dependencies between header files.
- Style cleanup.
- Add DEVICE_SUSPEND and DEVICE_RESUME methods.
- Move to a single-phase interrupt setup scheme.
Kernel builds on the Alpha are brken until Doug gets a chance to incorporate
these changes on that side.
Agreed to in principle by: dfr
Major changes to the generic device framework for FreeBSD/alpha:
* Eliminate bus_t and make it possible for all devices to have
attached children.
* Support dynamically extendable interfaces for drivers to replace
both the function pointers in driver_t and bus_ops_t (which has been
removed entirely. Two system defined interfaces have been defined,
'device' which is mandatory for all devices and 'bus' which is
recommended for all devices which support attached children.
* In addition, the alpha port defines two simple interfaces 'clock'
for attaching various real time clocks to the system and 'mcclock'
for the many different variations of mc146818 clocks which can be
attached to different alpha platforms. This eliminates two more
function pointer tables in favour of the generic method dispatch
system provided by the device framework.
Future device interfaces may include:
* cdev and bdev interfaces for devfs to use in replacement for specfs
and the fixed interfaces bdevsw and cdevsw.
* scsi interface to replace struct scsi_adapter (not sure how this
works in CAM but I imagine there is something similar there).
* various tailored interfaces for different bus types such as pci,
isa, pccard etc.
