firmware requests to do so. This cures severe overhating (> 120 C) observed
on many laptops, being also on par with the specification(s). This can be
reverted by using the new "hw.acpi.cpu.dynamic" sysctl variable.
(a) This should be removed once C-states are supported.
(b) As there seems to be no reliable way to detect whether C1E is present,
the quirk blindly assumes that C1E is used on families 10h and 11h.
required information. Problem found and diagnosed by jakllsch@; on some AMD
systems vendors fill _PSS correctly, but do not duplicate the data in XPSS.
this, the structure acpi_pciinfo now tells whether the ACPI
device node is a PCI bridge, a regular PCI device, or both.
Problem reported by jmcneill@, who also suggested the solution.
ok jmcneill@, jruoho@
control and output switching, through ACPI video extensions.
TODO: use wsconsctl(8) instead of sysctl(8) for brightness control.
ok jruoho@
also discussed with cegger@ and jmcneill@
don't use ACPI on BIOS which advertise release years <= 2000. This
can be changed by setting option ACPI_BLACKLIST_YEAR=0 or by setting
acpi_force_load=1.
still matches more boards that just the one with the problem.
Interrupts from the SATA controllers on my MSI K8N Neo3 boards
(which both versions of this quirk matched) are broken when ACPI
is disabled. My board does not exhibit AE_AML_INFINITE_LOOP
problems.
If we want to avoid manually specifying RB_MD2 in boothowto on
pgoyette@'s board, we're going to have to find another way; perhaps
with the DMI strings available from pmf(9).
Anyhow, some boards needing RB_MD2 during boot(8) is in my opinion
better than others needing to set acpi_force_load in ddb or gdb.
Note that the solution is not optimal. If ichlpcib(4) provides SpeedStep
support, possible I/O resource conflicts may occur with acpicpu(4). Ideally,
as noted for instance in Windows design documents, ichlpcib(4) should never
expose SpeedStep when ACPI is being used. The probability for potential race
conditions is however very small, being limited to few P4-era machines and
being dependent on user actions.
for an unknown notify. (The ACPI drivers should really not print anything
as we now have a global notify handler that can catch the debug information.)
will go backwards; K7 will not be supported already due doubts about
availability and reliability of ACPI during that era. Some unfortunate code
duplication is present (but not overly much). Thanks to cegger@ and jakllsch@
for patiently testing this.
do the status-check when the comparison value reported by BIOS is not zero.
The uncertainty noted in the previous commit still applies. But if we ever
see a timeout again, it will likely be either a firmware bug or a special
case like the Intel Turbo Boost.
ACPI_NOTIFY_DEVICE_WAKE. Control method power and sleep buttons can
generate this event upon waking from G1 sleep to indicate that it was
responsible for waking the system.
- XPSS spec says that Status{,Mask} and Control{,Mask} buffers are 8 bytes
- use ACPI_GET64 macros instead of memcpy when reading from buffers
This makes acpicpu work again on my VIA C7-M, whose firmware reports
malformed XPSS packages but has a working _PSS
invariant APIC timer or an "ARAT" ("always running APIC timer"). This means
that the APIC timer may keep ticking at the same rate also in deep C-states
with some new or forthcoming Intel CPUs.
Intel processors. The invariance means that TSC runs at a constant rate
during all ACPI state changes. If it is variant, skew may occur and TSC is
generally unsuitable for wall clock services. This is especially relevant
with C-states; with variant TSC, the whole counter may be stopped with states
larger than C1. All x86 CPUs before circa mid-2000s can be assumed to have a
variant time stamp counter.
config_interrupts(9) to be executed. This is necessary because: (a) the
initialization routines must be run only once after interrupts are enabled
and (b) all ACPI CPUs have attached.
Comparable to T-states, this gives effectively a window of available
performance states for passive cooling. An example:
Init: max = 0, min = Pn.
Time j. Time j + 1.
----------- -----------
2000 MHz P0 max P0
P1 P1 max
P2 ==> P2
P3 P3 min
P4 P4
P5 min P5
500 Mhz Pn Pn
----------- -----------
Search: repeat (i = P0; i <= P5) repeat (i = P1; i <= P3)
1. Initialize P-states properly to P0. It is processor-specific
what value we might get without initialization. (Some AMD CPUs
have even specific registers for the state after cold reset.)
2. Following design notes for Windows, set the lowest-power P-state
upon suspend and restore the saved state after resume.
dynamic maximum is nonexistent. Unsurprisingly, there is vagueness in the
standards; in ACPI 3.0 and 4.0 it is clearly indicated that also these methods
must be present, but the earlier standards are less stringent. Without too
much effort, at least one old P4-system was located that lacks _PPC.
Remarks:
1. Native instructions are supported only on Intel. Native support for
other x86 vendors will be investigated. By assumption, AMD and others
use the I/O based approach.
2. The existing code, INTEL_ONDEMAND_CLOCKMOD, must be disabled in
order to use acpicpu(4). Otherwise fatal MSR races may occur.
Unlike with P-states, no attempt is done to disable the existing
implementation.
3. There is no rationale to export controls to user land.
4. Throttling is an artefact from the past. T-states will not be used for
power management per se. For CPU frequency management, P-states are
preferred in all circumstances. No noticeable additional power savings
were observed in various experiments. When the system has been scaled
to the highest (i.e. lowest power) P-state, it is preferable to move
from C0 to deeper C-states than it is to actively throttle the CPU.
5. But T-states need to be implemented for passive cooling via acpitz(4).
As specified by ACPI and Intel documents, these can be used as the
last line of defence against critical thermal conditions. Support
for this will be added later.
(required for interaction with T-states), and (3) use aprint_debug(9)
instead of the ACPI_DEBUG_PRINT(x) macro for the dynamic frequency changes
(for the time being, people need easier way to observe the dynamic changes).
/*
* XXX: The pci_find_device(9) function only deals with
* attached devices. Change this to use something like
* pci_device_foreach(), and implement it for IA-64.
*/
functional, the previously loaded EST code may have used frequencies that
are not present in the BIOS. This will cause failures since acpicpu(4) will
treat these unknown frequencies as errors. "Fix" this by initializing the
cached P-state to P0, regardless of what the true state might be.
Remarks:
1. All processors (x86 or not) for which the vendor has implemented
ACPI I/O access routines are supported. Native instructions are
currently supported only for Intel's "Enhanced Speedstep". Code for
"PowerNow!" (AMD) will be merged later. Native support for VIA's
"PowerSaver" will be investigated.
2. Backwards compatibility with existing userland code is maintained.
Comparable to the case with cpu_idle(9), the ACPI CPU driver
installs alternative functions for the existing sysctl(8) controls.
The "native" behavior (if any) is restored upon detachment.
3. The dynamic nature of ACPI-provided P-states needs more investigation.
The maximum frequency induced (but not forced) by the firmware may
change dynamically. Currently, the sysctl(8) controls error out with
a value larger than the dynamic maximum. The code itself does not
however yet react to the notifications from the firmware by changing
the frequencies in-place. Presumably the system administrator should
be able to choose whether to use dynamic or static frequencies.
This can help when dealing with problem reports, as the user does not need
to reboot nor compile a kernel. Instead: 'modload -b dump=true acpiverbose'.
when the idle-information is being updated (e.g. due acpiacad(4) events),
we can not enter the idle-loop. The lock must run at the same priority
(IPL_NONE) as ACPICA's mutexes obtained via AcpiOsCreateMutex() a.k.a.
AcpiOsCreateSemaphore(). Also check want_resched as the first thing and
clarify the suspend/resume path.
There is still one race condition identified: when the driver is loaded as a
module, we must gracefully kick all CPUs out from the ACPI idle-loop upon
detachment.
It was analyzed that this DSDT busy-loops some unknown PCI memory regions in
several places. Because the regions are apparently almost constant, this
causes several conditions where the interpreter might enter into an infinite
loop. Luckily ACPICA detects this and rightly spams AE_AML_INFINITE_LOOP
warnings.
Not much we can do. Declare as broken beyond repair. Set acpi_force_load=1
to use ACPI or use a custom DSDT.
sanity check before casting to the GAS. Rename the _CSD structure; the
optional "cross logical processor dependency information" is almost
identical in C, P, and T states. Add some comments to the header.
activity (BM_STS) by reading from the PM1 register. According to the Intel
processor specification for ACPI, the FFH GAS encoding may provide a hint
that the check is not required. This may help some systems to enter C2/C3
even when e.g. usb(4) keeps the BM_STS bit always enabled.
existing ACPICPU_FLAG_C, as was intended. Set that flag only after the
idle-loop has been installed, so that the notify handler errors out if an
interrupt is received before the idle-loop is in place.
This makes my laptop boot instead of panic:
panic: kernel diagnostic assertion "native_idle != NULL" failed: file "../../../../arch/x86/acpi/acpi_cpu_md.c", line 155
fatal breakpoint trap in supervisor mode
type 1 code 0 rip ffffffff8022e4ad cs 8 rflags 246 cr2 0 cpl 0 rsp ffff80004c37db10
trace
breakpoint() at netbsd:breakpoint+0x5
panic() at netbsd:panic+0x2ba
kern_assert() at netbsd:kern_assert+0x2d
acpicpu_md_idle_stop() at netbsd:acpicpu_md_idle_stop+0x62
acpicpu_cstate_callback() at netbsd:acpicpu_cstate_callback+0x34
sysmon_task_queue_thread() at netbsd:sysmon_task_queue_thread+0x41
1. ACPI seems to define cpuids 1..n; we define 0..n-1. Adjust for that
2. My laptop is dual core, but ACPI reports 4 cpu nodes. Instead of
attaching the unmatched ones, make the match fail. Do we want to
attach and do nothing instead?
3. Create a flag, and only set it after we are completely initialized,
so the sysmon thread does not try to access unitialized state.
