The current support for controlling i2c bus speed is an inconsistant mess.
There are 4 symbolic speed values defined, UNKNOWN, SLOW, FAST, FASTEST.
It seems to be universally assumed that SLOW means the standard 100KHz
rate from the original spec. Nothing ever calls iicbus_reset() with a
speed of FAST, although some drivers would treat it as the 400KHz standard
speed. Mostly iicbus_reset() is called with the speed set to UNKNOWN or
FASTEST, and there's really no telling what any individual driver will do
with those.
The speed of an i2c bus is limited by the speed of the slowest device on
the bus. This means that generally the bus speed needs to be configured
based on the board/system and the components within it. Historically for
i2c we've configured with device hints. Newer systems use FDT data and it
documents a clock-frequency property for i2c busses. Hobbyists and
developers are likely to want on the fly changes. These changes provide
all 3 methods, but do not require any existing drivers to change to use
the new facilities.
This adds an iicbus method, iicbus_get_frequency(dev, speed) that gets the
frequency for the requested symbolic speed. If the symbolic speed is SLOW
or if there is no speed configured for the bus, the returned value is
100KHz, always. Otherwise, if bus speed is configured by hints, fdt,
tunable, or sysctl, that speed is returned. It also adds a helper
function, iicbus_init_frequency() that any bus driver subclassed from
iicbus can initialize the frequency from some other source of info.
Initial driver implementations are provided for Freescale and TI.
Differential Revision: https://reviews.freebsd.org/D1174
PR: 195009
After resource allocation and release, resource list entry
stays non-NULL. This causes panic in ofwbus_alloc_resource()
on subsequent resource allocation.
Clean appropriate list entry on release to avoid this.
Obtained from: Semihalf
Reviewed by: ian
Sponsored by: The FreeBSD Foundation
node's interrupts=<...> property creating resource list entries with a
single common implementation. This change makes ofw_bus_intr_to_rl() the
one true copy of that code and removes the copies of it from other places.
This also adds handling of the interrupts-extended property, which allows
specifying multiple interrupts for a node where each interrupt can have a
separate interrupt-parent. The bindings for this state that the property
cells contain an xref phandle to the interrupt parent followed by whatever
interrupt info that parent normally expects. This leads to having a
variable number of icells per interrupt in the property. For example you
could have <&intc1 1 &intc2 26 9 0 &intc3 9 4>.
Differential Revision: https://reviews.freebsd.org/D803
an entry in the xref list if one doesn't already exist for the given handle.
On a system that uses phandle properties, the init-time scan of the tree
which builds the xref list will pre-create entries for every xref handle
that exists in the data. On systems where the xref and node handles are
synonymous there is no phandle property in referenced nodes, and the xref
list will initialize to an empty state. In the latter case, we still need
to be able to associate a device_t with an xref handle, so we create list
entries on the fly as needed. Since the node and xref handles are
synonymous, we have all the info needed to create a list entry at device
registration time.
The downside to this change is that it basically allows on the fly creation
of xref handles as synonyms of node handles, and the association of a
device_t with them. Whether this is a bug or a feature is in the eye of
the beholder, I guess.
for the node. The default routine returns the untranslated handle, which
is sometimes useful, but sometimes you really need to know there's no
entry in the xref<->node<->device translation table.
xref handle, and for registering that association. Also use the same data
for faster translations between node and xref handles.
Now when fdt properties contain &othernode references, a driver can find
the device instance that corresponds to &othernode, and thus can use
interfaces provided by that instance.
Reviewed by: nwhitehorn
#gpio-cells property.
Add a new ofw_bus method (OFW_BUS_MAP_GPIOS()) that allows the GPIO
controller to implement its own mapping to deal with gpio-specifiers,
allowing the decoding of gpio-specifiers to be controller specific.
The default ofw_bus_map_gpios() decodes the linux standard (#gpio-cells =
<2>) and the FreeBSD standard (#gpio-cells = <3>).
It pass the gpio-specifier flag field to the children as an ivar variable so
they can act upon.
This change makes ofw_iicbus attach to iicbb(4) controllers in addition to
the already supported i2c host bridges (iichb).
On iicbb(4) allow the direct access of the OFW parent node by its children,
so they can be directly attached to iicbb(4) node on the DTS without the
need of describing the i2c bus.
Approved by: adrian (mentor, implicit)
a sub-node of nexus (ofwbus) rather than direct attach under nexus. This
fixes FDT on x86 and will make coexistence with ACPI on ARM systems easier.
SPARC is unchanged.
Reviewed by: imp, ian
process "status" properties of OF nodes.
I've avoided adding new KOBJ methods here so that we don't have to modify
every ofw_bus in the tree. Since 100% of implementations of ofw_bus use
only ofw_bus_gen_*(), it might be worth garbage-collecting the other
methods as well.
strings and include arbitrary information (IRQ line/domain/sense). When the
ofw_bus_map_intr() API was introduced, it assumed that, as on most systems,
these were either 1 cell, containing an interrupt line, or 2, containing
a line number plus a sense code. It turns out a non-negligible number of
ARM systems use 3 (or even 4!) cells for interrupts, so make this more
general.
in /chosen, be ihandles. The ePAPR spec makes those cross-reference phandles,
since FDT has no concept of ihandles. Have the OF FDT CI module interpret
queries about ihandles as cross-reference phandles.
fdt_next_property_offset() API. The old code would sometimes (e.g. on
the device tree supplied by the RB800 boot loader) get confused and stop
partway through listing properties.
MFC after: 1 week
associates compat strings with arbitrary values that mean something to
the driver. This is handy for drivers that support several variations
of similar hardware and need to know which one matched.
Reviewed by: imp, jmg, nwhitehorn
- ofw_bus_map_intr()
Maps an (iparent, IRQ) tuple to a system-global interrupt number in some
platform dependent way. This is meant to be implemented as a replacement
for [FDT_]MAP_IRQ() that is an MI interface that knows about the bus
hierarchy.
- ofw_bus_config_intr()
Configures an interrupt (previously mapped) based on firmware sense flags.
This replaces manual interpretation of the sense field in bus drivers and
will, in a follow-up, allow that interpretation to be redirected to the PIC
drivers where it belongs. This will eventually replace the tables in
/sys/dev/fdt/fdt_ARCH.c
The PowerPC/AIM code has been converted to use these globally, with an
implementation in terms of MAP_IRQ() and powerpc_config_intr(), assuming
OpenPIC, at the bus root in nexus(4). The ofw_bus_config_intr() will shortly
be integrated into pic_if.m and bounced through nexus into the PIC tree.
FDT integration will happen significantly later due to larger testing
requirements. This patch in general also lays the groundwork for the removal
of /sys/dev/fdt/fdt_ARCH.c and machine/fdt.h.
and OF_searchencprop(). I thought about using the element size parameter
to OF_getprop_alloc() to do endian-switching automatically, but it breaks
use with structs and a *lot* of FDT code (which can hopefully be moved to
these new APIs).
MFC after: 2 weeks
by encode-int. Specifically, it takes a set of 32-bit cell values and
changes them to host byte order. Most non-string instances of OF_getprop()
should be using this function, which is a no-op on big-endian platforms.
used as cross-references in the device tree and phandles as used by the
Open Firmware client interface are in different namespaces. This include
IBM pSeries hardware as well as FDT systems. FDT certainly abuses
ihandles for this purpose and should be modified to use this API
eventually. This changes no behavior on systems where FreeBSD already
worked.
Reviewed by: marius
Approved by: re (kib)
MFC after: 2 weeks
alias it to the contents of the output property if it is defined. This
avoids a panic when booting machines (QEMU) where the output-device
property is not defined.
Since output-device is free-form and potentially conflicts with other
entries in /dev, I also am not sure we should be doing the aliasing at
all, but this at least makes things work again.
Approved by: re (kib)
