This adds the concept of "operating points," combinations of frequency
and voltage at which the cpu is known to work correctly. Some day these
should come from FDT data, but for now the table is hard-coded.
This also allows tuning the min and max operating frequencies. The min
frequency is what the thermal management code will slow down to if the
core temperature gets too high. The max frequency is what gets used if
the temperature is okay.
Normally the max cannot be set higher than the value burned into the
ocotp fuses as the chip's rated max, but there is now a new sysctl+tunable
cpu_overclock_enable; when set to non-zero it allows raising the frequency
above the ocotp value: USE WITH CARE! (At least one of my imx6 boards
has a cpu whose ocotp values never got set correctly; they claim a max
of 792mhz, but the physical markings on the chip say it's good to 1ghz.)
Because all these values affect the entire SoC, there is a new sysctl
node, hw.imx6, where all these values live. The values that are currently
under dev.imx6_anatop.0 should probably move to hw.imx6 too, because
"anatop" doesn't even mean anything to me, let alone to an end user.
and the functionality it provided into arm/exception.S. Rename the main
irq handling routine from arm_handler_execute() to arm_irq_handler() to
make it more congruent with how other exception handlers are named, and
also update its signature to reflect what has long been reality: it is
passed just a trapframe pointer, no interrupt number argument.
appropriate for each of the 'foo' in the tree. This will allow us to
compile them together (although symbol conflicts prevent us from doing
that today, this just fixes the file name collision).
implementation in arm/machdep.c. Most arm platforms either don't need to
do anything, or just need to call the standard eventtimer init routines.
A generic implementation that does that is now provided via weak linkage.
Any platform that needs to do something different can provide a its own
implementation to override the generic one.
- Don't use spaces or dots in the eventtimer or timecounter names.
They turn into sysctl node names, and it's just confusing.
- Use comparator #3 instead of #1 for one-shot events. There's an
extra 1-cycle penalty in the hardware for accessing the registers
for comparator 1, no point in paying that penalty.
- Lower the quality of the eventtimer from 1000 to 800, because the
device can't support PERCPU timers and some other device in the system
may be able to provide that.
The temperature monitor device is enabled to sample the die temperature at
16hz. The temperature is published via sysctl. A callout routine at 10hz
monitors the temperature and throttles back the cpu if the temperature
goes over a user-settable throttle point (by default 10C less than the
critical high-point temperature for the chip). The hardware is supposed
to be able to deliver an interrupt when the temperature exceeds a settable
limit, but the interrupt never arrives so for now a callout does the job.
At attach time we read the maximum cpu frequency the chip is allowed to run
at and the cpu is set to run at that speed. It's reported at attach time.
A sysctl variable reports the current speed when queried.
New sysctl values:
dev.imx6_anatop.0.cpu_mhz: 984
dev.imx6_anatop.0.temperature: 37.9C
dev.imx6_anatop.0.throttle_temperature: 95.0C
Steven Lawrance did the initial heavy lifting on this, but I changed
enough stuff that I'm the one to blame if anything breaks.
Submitted by: Steven Lawrance <stl@koffein.net>
is attached, by establishing a temporary mapping of the registers when
necessary. This is a temporary measure to keep progress moving; in the
long run we need better control over the order in which devices attach
(better than "the order they appear in the fdt dts source").
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
to check the status property in their probe routines.
Simplebus used to only instantiate its children whose status="okay"
but that was improper behavior, fixed in r261352. Now that it doesn't
check anymore and probes all its children; the children all have to
do the check because really only the children know how to properly
interpret their status property strings.
Right now all existing drivers only understand "okay" versus something-
that's-not-okay, so they all use the new ofw_bus_status_okay() helper.
shifts into the sign bit. Instead use (1U << 31) which gets the
expected result.
This fix is not ideal as it assumes a 32 bit int, but does fix the issue
for most cases.
A similar change was made in OpenBSD.
Discussed with: -arch, rdivacky
Reviewed by: cperciva
fdtbus in most cases. This brings ARM and MIPS more in line with existing
Open Firmware platforms like sparc64 and powerpc, as well as preventing
double-enumeration of the OF tree on embedded PowerPC (first through nexus,
then through fdtbus).
This change is also designed to simplify resource management on FDT platforms
by letting there exist a platform-defined root bus resource_activate() call
instead of replying on fdtbus to do the right thing through fdt_bs_tag.
The OFW_BUS_MAP_INTR() and OFW_BUS_CONFIG_INTR() kobj methods are also
available to implement for similar purposes.
Discussed on: -arm, -mips
Tested by: zbb, brooks, imp, and others
MFC after: 6 weeks
