when using an APIC. This simplifies the APIC code somewhat and also allows
us to be pedantically more compliant with ACPI which mandates no use of
mixed mode.
IRQ 0 and not an ExtINT pin. The MADT enumerators ignore the PC-AT flag
and ignore overrides that map IRQ 0 to pin 2 when this quirk is present.
- Add a block comment above the quirks to document each quirk so that we
can use more verbose descriptions quirks.
MFC after: 2 weeks
- Require the APIC enumerators to explicitly enable mixed mode by calling
ioapic_enable_mixed_mode(). Calling this function tells the apic driver
that the PC-AT 8259A PICs are present and routable through the first I/O
APIC via an ExtINT pin. The mptable enumerator always calls this
function for now. The MADT enumerator only enables mixed mode if the
PC-AT compatability flag is set in the MADT header.
- Allow mixed mode to be enabled or disabled via a 'hw.apic.mixed_mode'
tunable. By default this tunable is set to 1 (true). The kernel option
NO_MIXED_MODE changes the default to 0 to preserve existing behavior, but
adding 'hw.apic.mixed_mode=0' to loader.conf achieves the same effect.
- Only use mixed mode to route IRQ 0 if it is both enabled by the APIC
enumerator and activated by the loader tunable. Note that both
conditions must be true, so if the APIC enumerator does not enable mixed
mode, then you can't set the tunable to try to override the enumerator.
to map. If the checksum fails, the table is unmapped and a NULL pointer
returned.
- For ACPI version >= 2.0, check the extended checksum of the RSDP.
AcpiOsGetRootPointer() already checks the version 1.0 checksum.
- Remap the full MADT table at the end of madt_probe() so that we verify
its checksum before saying it is really there.
Requested by: njl
and intr_polarity enums for passing around interrupt trigger modes and
polarity rather than using the magic numbers 0 for level/low and 1 for
edge/high.
- Convert the mptable parsing code to use the new ELCR wrapper code rather
than reading the ELCR directly. Also, use the ELCR settings to control
both the trigger and polarity of EISA IRQs instead of just the trigger
mode.
- Rework the MADT's handling of the ACPI SCI again:
- If no override entry for the SCI exists at all, use level/low trigger
instead of the default edge/high used for ISA IRQs.
- For the ACPI SCI, use level/low values for conforming trigger and
polarity rather than the edge/high values we use for all other ISA
IRQs.
- Rework the tunables available to override the MADT. The
hw.acpi.force_sci_lo tunable is no longer supported. Instead, there
are now two tunables that can independently override the trigger mode
and/or polarity of the SCI. The hw.acpi.sci.trigger tunable can be
set to either "edge" or "level", and the hw.acpi.sci.polarity tunable
can be set to either "high" or "low". To simulate hw.acpi.force_sci_lo,
set hw.acpi.sci.trigger to "level" and hw.acpi.sci.polarity to "low".
If you are having problems with ACPI either causing an interrupt storm
or not working at all (e.g., the power button doesn't turn invoke a
shutdown -p now), you can try tweaking these two tunables to find the
combination that works.
different BIOSs use the same exact settings to mean two very different and
incompatible things for the SCI. Thus, if the SCI is remapped to a PCI
interrupt, we now trust the trigger/polarity that the MADT provides by
default. However, the SCI can be forced to level/lo as 1.10 did by setting
the tunable "hw.acpi.force_sci_lo" to a non-zero value from the loader.
Thus, if rev 1.10 caused an interrupt storm, it should nwo fix your
machine. If rev 1.10 fixed an interrupt storm on your machine, you
probably need to set the aforementioned tunable in /boot/loader.conf to
prevent the interrupt storm.
The more general problem of getting the SCI's trigger/polarity programmed
"correctly" (for some value of correctly meaning several workarounds for
broken BIOSs and inconsistent "implementations" of the ACPI standard) is
going to require more work, but this band-aid should improve the current
situation somewhat.
Requested by: njl
can look at the ACPI tables. If the startup fails, we panic and tell the
user to try rebooting with ACPI disabled. Previously in this case we
would try to use $PIR interrupt routing which only works for the atpic
while using the apic to handle interrupts which would result in misrouted
interrupts and a hang at boot time with no error message.
- Read the SCI out of the FADT instead of hardcoding 9 when checking to see
if an interrupt override entry is for the SCI.
- Try to work around some BIOS brain damage for the SCI's programming by
forcing the SCI to be level triggered and active low if it is routed
to a non-ISA interrupt (greater than 15) or if it is identity mapped with
edge trigger and active high polarity. This should fix some of the hangs
with device apic and ACPI that some people see.
Reviewed by: njl
SI_SUB_CPU - 1 and probe enumerators, probe CPUs, and setup the local
APIC programming all at SI_SUB_CPU / SI_ORDER_FIRST. This is needed to
help get the ACPI module working again as it moves the APIC enumeration
code after SI_SUB_KLD.
- In the MADT parser, use mp_maxid rather than MAXCPU to terminate a loop
when assigning per-cpu ACPI IDs to avoid a dependency on 'options SMP'.
- Allow the apic device to be disabled via 'hint.apic.0.disabled' from the
loader. Note that since this is done in the local APIC code, it works
for both the ACPI and non-ACPI cases.
Approved by: re (scott / blanket)
interrupt such as IRQ 22 or 19. However, the ACPI BIOS still routes
interrupts from some PCI devices to the same intpin calling the pin
IRQ 22. Thus, ACPI expects to address a single interrupt source via two
different names. To work around this, if the SCI is remapped to a non-ISA
interrupt (i.e., greater than 15), then we use
acpi_OverrideInterruptLevel() function to tell ACPI to use IRQ 22 or 19
rather than IRQ 9 for the SCI.
Previously we would change IRQ 22 or 19's name to IRQ 9 when we encountered
such an Interrupt Source Override entry in the MADT which routed the SCI
properly but left PCI devices mapped to IRQ 22 or 19 w/o a routable
interrupt.
Tested by: sos
pin that is used by the default identity mapping if it still maps to the
old vector. The ACPI case might need some tweaking for the SCI interrupt
case since ACPI likes to address the intpin using both the IRQ remapped to
it as well as the previous existing PCI IRQ mapped to it.
Reported by: kan
APIC Descriptor Table to enumerate both I/O APICs and local APICs. ACPI
does not embed PCI interrupt routing information in the MADT like the MP
Table does. Instead, ACPI stores the PCI interrupt routing information
in the _PRT object under each PCI bus device. The MADT table simply
provides hints about which interrupt vectors map to which I/O APICs. Thus
when using ACPI, the existing ACPI PCI bridge drivers are sufficient to
route PCI interrupts.
